219 results on '"Watts DM"'
Search Results
2. Tales of the Transgressive Body - more than a single story: DST in a climate of transgression
- Author
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Watts, DM, Crowe, N, and Waite, G
- Published
- 2018
3. O Que Pode Falhar? Reflexão Sobre As Dificuldades De Alunos Do Ensino Secundário No Relatório Tipo 'V De Gowin' Para A Melhoria Da Formação Inicial De Professores
- Author
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Watts, DM, Lopes, B, Abrantes, I, and Magalhaes, P
- Published
- 2018
4. Muslim Asian girls and science
- Author
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Watts, DM and Salehjee, S
- Published
- 2018
5. Safety and Immunogenicity of Rift Valley Fever MP-12 and a Novel arMP-12?NSm21/384 Recombinant Vaccine Candidate in Native Breed of Black Head Sheep (Ovis aries) from Tanzania
- Author
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Matiko Mk, Nyundo Sb, Wambura Pn, Rowl, Adamson Ek, Palermo Pm, Bettinger Ge, Morrill Jc, and Watts Dm
- Subjects
Veterinary medicine ,biology ,Immunogenicity ,Immunology ,Antibody titer ,Viremia ,medicine.disease ,biology.organism_classification ,Vaccination ,Titer ,Plaque reduction neutralization test ,Virology ,Drug Discovery ,medicine ,Immunology and Allergy ,Rift Valley fever ,Ovis - Abstract
Objective: Rift Valley fever (RVF) is a mosquito-borne zoonotic viral disease that affects humans and ruminants in Africa and the Arabian Peninsula. Efforts to develop effective vaccines have had limited success. Therefore, the aim of this study was to evaluate the safety and immunogenicity of RVF MP-12, and arMP-12ΔNSm21/384 vaccine candidates in sheep. Methods: One group of 6 sheep was vaccinated intramuscularly (IM) each with one ml of 1×105 PFU/ml of the RVF MP-12 and 9 sheep were inoculated IM each with one ml of the arMP-12ΔNSm21/384 vaccine candidate, and two control sheep received one ml each of only Eagle's Minimum Essential Medium. Blood samples obtained on days 14 and 0 before vaccination and on days 3, 4, and 5 post vaccination (PV) were tested for RVFV in Vero cells and by RT PCR assay, and samples collected at interval PV through day 87 and on days 7, 14 and 21 following revaccination on day 87 PV to test for RVFV neutralizing antibody response by the plaque reduction neutralization test. Results: All animals, including the controls remained in good health during the PV period as supported by normal body temperature, and the absence of clinical manifestations throughout this study. A viremia was not detected in any of the animals. Six of 6 animals that received the RVF MP-12 and 8 of 9 animals that received the arMP-12ΔNSm21/384 had antibody titers that ranged from 1:10 on day 5 PV to as high as 1:40 to 1:160 through day 87 PV. The antibody titers for these 15 animals following revaccination on day 87 PV with 1×104 PFU/ml of the MP-12 vaccine increased rapidly and by day 21 PV the titers for most animals ranged from 1:160 to 1:640. Conclusion: Overall, these findings based on a limited number of sheep indicated that both the MP-12 and the arMP-12ΔNSm21/384 are promising vaccine candidates for the prevention of RVF in sheep in Africa.
- Published
- 2018
6. A paradigm shift in the teaching and learning of science using technology in Mauritius: Making a case for incorporating the affective domain
- Author
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Ramma, Y, Bholoa, A, Watts, DM, and Samy, M
- Subjects
pedagogical technological integrated medium ,knowledge construction ,affective domain ,conceptual understanding - Abstract
Through a systematic review of the literature we indicate how the affective domain has been consistently overlooked by current frameworks for integrating technology in the teaching and learning of Science. We argue that presently technology is overwhelmingly employed in education in Mauritius as a source of information rather than a process-based means of knowledge construction which is the premise for conceptual understanding. In this theoretical paper we propose a framework, pedagogical technological integrated medium (PTIM), that builds on the existing premises of pedagogy, content/contextual knowledge and technology to include the affective domain at the common intersection of these three premises. The affective dimension is further explored as a space for interaction between learners, teachers, parents and the social dimension in a series of stages encapsulating, home tasks based on prior knowledge with the lesson delivery at school. We posit that a succinct synchronisation of these various elements would ensure successful implementation of the framework.
- Published
- 2017
7. Family science and intergenerational learning
- Author
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Zwozdiak-Myers, P, Watts, DM, and Kanhadilok, P
- Published
- 2016
8. But is it science?
- Author
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Watts, DM, Salehjee, S, and Essex, J
- Abstract
In October 2014, the International Safeguards for Children in Sport were launched. These Safeguards were developed, implemented, and evaluated based on a pilot process which took place over the preceding 2 years. Throughout this piloting phase, a range of qualitative techniques were employed to capture the experiences of people within 32 of the organizations that were working toward the International Safeguards. The participant organizations varied based on their geographical focus (e.g., local, national, and international) as well as their mission (e.g., participation, competition, and sport for development). Based on a thematic analysis, eight key pillars were identified on which systems which safeguard children can be built. These are known as the CHILDREN pillars: Cultural sensitivity, Holistic, Incentives, Leadership, Dynamic, Resources, Engagement, and Networks. Illustrative examples are provided and the future directions of this project will be discussed
- Published
- 2016
9. Academic growth and scholarship of teaching and learning: The impact of research
- Author
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Watts, DM, Pedrosa-de-Jesus, H, Moreira, A, da Silva Lopes, B, Guerra, C, Pedrosa, J, Cunha, A, and Almeida, A
- Abstract
The research-funded project we describe here has been conducted over the extensive period 2001–15. The research problem relates to the institutional and professional changes required to promote and encourage greater teacher and student engagement in learning across undergraduate studies. The emphasis in this paper is upon impact. Research can be seen as systematic inquiry for the creation and development of knowledge, and the process of measuring and describing the impact of academic research is becoming increasingly important in Europe and around the world. To measure impact requires some measure of both the generation of knowledge and the value of the knowledge generated. Knowledge itself is immeasurable, at best it is observed through expressions of knowledge such as publications, papers, patents, and students’ and, in this case, teachers’ perceptions. Project funding: has been awarded through the Fundação para a Ciência e a Tecnologia (FCT), Portugal, Project: PTDC/CPE-CED/117516/2010
- Published
- 2015
10. Reflectivity, reflective questions, self-questioning and managing professionally situated practice
- Author
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Malthouse, R, Roffey-Barentsen, R, and Watts, DM
- Subjects
Situated reflective practice ,Reflective questions ,Work-place problems ,Situated reflective questions ,Self-questioning - Abstract
Reflective self-questioning arises within the work-place when people are confronted with professional problems and situations. This paper focuses on reflective and ‘situated reflective’ questions in terms of self-questioning and professional workplace problem solving. In our view, the situational context, entailed by the setting, social and personal/individual perspectives, is interactional. The supporting empirical data is drawn from our work with two groups in their tertiary phase of education: professional trainers within a large corporate organisation and para-professionals within a large college system; each embraces phenomenological principles. The discussions of situated reflective practice (SRP) entail those circumstances where change is visited upon the individual by forces outside their immediate control. The positive sense of SRP is that it can prepare an individual for anticipated change, and is therefore considered a method of change management. The situation acts as a catalyst for the thought.
- Published
- 2015
11. A study of academic development in universities through innovative approaches in teaching, assessment and feedback
- Author
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Watts, DM, Pedrosa-de-Jesus, H, Moreira, A, da Silva Lopes, B, Guerra, C, Pedrosa, J, Cunha, A, and Almeida, A
- Subjects
Engagement ,Teacher ,Undergraduate studies ,Professional changes ,Student ,Institutional - Abstract
The research-funded project we describe here has been conducted over the extensive period 2001–15. The research problem relates to the institutional and professional changes required to promote and encourage greater teacher and student engagement in learning across undergraduate studies. The emphasis in this paper is upon impact. Research can be seen as systematic inquiry for the creation and development of knowledge, and the process of measuring and describing the impact of academic research is becoming increasingly important in Europe and around the world. To measure impact requires some measure of both the generation of knowledge and the value of the knowledge generated. Knowledge itself is immeasurable, at best it is observed through expressions of knowledge such as publications, papers, patents, and students’ and, in this case, teachers’ perceptions. This research was financed by European Founds “FEDER através do Programa Operacional Factores de Competitividade – COMPETE” and by National Founds through “FCT – Fundação para a Ciência e a Tecnologia” project «PTDC/CPE-CED/117516/2010»
- Published
- 2015
12. Promoting academic development through situated critical reflection
- Author
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Watts, DM, Guerra, C, Pedrosa-de-Jesus, H, Cunha, A, and Almeida, A
- Subjects
Higher education ,Assessment ,Critical thinking ,Feedback - Abstract
Many changes in higher education derived from Europe-wide initiatives such as the Bologna process have given increasing attention to student-centred teaching approaches, allied to growth in teachers’ academic development (Clarke & Reid, 2013; HE Academy, 2011). Our study is one component of a long-standing project focused on ways to promote academic development in the context of higher education. Work since 2001 has provided a strong understanding of the dynamics of student-generated questioning, inquiry-based learning and academic practices (Pedrosa de Jesus, Lopes, Moreira & Watts, 2012).
- Published
- 2014
13. Voices from the classroom
- Author
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Roffey-Barentsen, J and Watts, DM
- Subjects
Plant biology ,Public understanding - Published
- 2014
14. The role of teacher’s written formative feedback on students’ critical thinking
- Author
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Pedrosa-de-Jesus, H, Guerra, C, Moreira, A, and Watts, DM
- Subjects
Higher education ,Critical thinking ,Feedback - Abstract
Formative feedback in higher education has positive effects when it facilitates the development of students’ reflection and self-assessment in learning. That said, the increasing pressures of workload on university teachers make the design of formative feedback strategies more difficult to implement). This study explores innovative ways for promoting teachers’ written formative feedback in the context of undergraduate studies and for assessing their effectiveness. The investigation entails close collaboration with one teacher of Biology at the University of Aveiro, Portugal, in the context of teaching ‘evolution’ over a semester (2012/2013). One of the particular challenges was to encourage 88 first-year biology undergraduates to produce critical analyses of a selected press note related to the topic of evolution (i.e., the advent of genetic diseases). The research approach we use is based on a critical social paradigm, assuming principles of action-research. Data were collected through naturalistic non-participant classroom observation and semi-structured interviews (conducted at the end of the semester). All written documents produced by participants were used as part of this analysis. Considering the nature of the data, we use content analysis. Preliminary results show that the teacher’s written comments increased opportunities for students to search for further information, to negotiate and take decisions within their group, to auto- and hetero-reflect before sending their critical analyses to the teacher. Group work allowed the development of critical thinking, collaboration and argumentation. This research was financed by European Founds “FEDER através do Programa Operacional Factores de Competitividade – COMPETE” and by National Founds through “FCT – Fundação para a Ciência e a Tecnologia” project «PTDC/CPE-CED/117516/2010»
- Published
- 2014
15. Striving against invalidity in qualitative research: Discussing a reflective framework
- Author
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Pedrosa, MH, Lopes, B, Watts, DM, Evans, C, and Kozhevnikov, M
- Subjects
Lecturing styles ,Research quality ,Approaches to teaching ,Naturalistic - interpretative paradigm ,Orientation to teaching - Abstract
The aim of this paper is to discuss a reflective validation framework related with the study of teaching approaches, teaching styles or teaching orientations of university academics. In the recent years, and particularly since the eighties, there have been a growing number of investigations linking teaching conceptions with teaching practices. The majority of investigations dealing with university teachers’ conceptions and practices draw their conclusions based on indirect observation, since data gathering involves mainly semi-structured interviews or the application of questionnaires and inventories. Therefore ‘only-half-the-story’ has been reported. The presented validation framework has a five-part three-stage structure and was built upon earlier work (Selvaruby, O’Sullivan, & Watts, 2007). In this model validity is conceptualized as an ‘iterative-interactive-process’, therefore integrating a set of specific strategies envisaging the maximization of scientific quality. The application of the model is illustrated by using it for the discussion of a longitudinal study involving the investigation of the relationship between questioning practices and Trigwell and co-workers’ concept of preferential teaching approaches (Trigwell, Prosser & Taylor, 1994). Field work of this naturalistic-interpretative research was conducted during two academic years (2009/2010 and 2010/2011) and implied close collaboration with a group of four university teachers lecturing biology to undergraduates. This work was financed by Fundação para a Ciência e a Tecnologia (SFRH/BD/44611/2008) and by Fundos FEDER através do Programa Operacional Fatores de Competitividade – COMPETE e por Fundos Nacionais através da FCT (PTDC/CPE-CED/117516/2010).
- Published
- 2013
16. Hepatitis B virus (HBV)/hepatitis D virus (HDV) coinfection in outbreaks of acute hepatitis in the Peruvian Amazon basin: the roles of HDV genotype III and HBV genotype F
- Author
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John L. Gerin, John L. Casey, McCarthy M, Grazia Anna Niro, Gomez H, Vega A, Hyams Kc, Ronald E. Engle, and Watts Dm
- Subjects
Adult ,Male ,Hepatitis B virus ,Adolescent ,Genotype ,viruses ,medicine.disease_cause ,Virus ,Disease Outbreaks ,Peru ,medicine ,Immunology and Allergy ,Humans ,biology ,virus diseases ,biochemical phenomena, metabolism, and nutrition ,Hepatitis B ,medicine.disease ,biology.organism_classification ,Virology ,Hepatitis D ,Infectious Diseases ,Hepadnaviridae ,Immunology ,Acute Disease ,Coinfection ,RNA, Viral ,Viral disease ,Hepatitis D virus ,Hepatitis Delta Virus - Abstract
Recurring outbreaks of acute hepatitis have been a significant cause of morbidity and mortality among Peruvian military personnel stationed in the Amazon Basin region of Peru. The role of hepatitis B virus (HBV) and hepatitis D virus (HDV) infection was investigated as the possible cause of acute hepatitis among 88 military patients stationed at four different jungle outposts during 1992-1993. Analysis of serum markers indicated that 95% (84/88) had evidence of acute HBV infection ; 64% (54/84) were also infected with HDV. Genetic analysis of PCR-amplified HDV and HBV fragments showed exclusively HDV genotype III and HBV genotype F. Furthermore, HDV RNA sequences were similar among patients from the same outpost but different from those at other jungle locations. The data suggested focal sources of HDV infection in the jungle environment of the outposts and, further, confirmed the unique association of HDV genotype III with severe cases of human disease in northern South America.
- Published
- 1996
17. Sexual practices and prevalence of HIV, HTLV-I/II, and Treponema pallidum among clandestine female sex workers in Lima, Peru.
- Author
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Trujillo L, Muñoz D, Gotuzzo E, Yi A, Watts DM, Trujillo, L, Muñoz, D, Gotuzzo, E, Yi, A, and Watts, D M
- Published
- 1999
- Full Text
- View/download PDF
18. Hepatitis B virus (HBV)/hepatitis D virus (HDV) coinfection in outbreaks of acute hepatitis in the Peruvian Amazon basin: the roles of HDV genotype III and HBV genotype F.
- Author
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Casey JL, Niro GA, Engle RE, Vega A, Gomez H, McCarthy M, Watts DM, Hyams KC, Gerin JL, Casey, J L, Niro, G A, Engle, R E, Vega, A, Gomez, H, McCarthy, M, Watts, D M, Hyams, K C, and Gerin, J L
- Abstract
Recurring outbreaks of acute hepatitis have been a significant cause of morbidity and mortality among Peruvian military personnel stationed in the Amazon Basin region of Peru. The role of hepatitis B virus (HBV) and hepatitis D virus (HDV) infection was investigated as the possible cause of acute hepatitis among 88 military patients stationed at four different jungle outposts during 1992-1993. Analysis of serum markers indicated that 95% (84/88) had evidence of acute HBV infection; 64% (54/84) were also infected with HDV. Genetic analysis of PCR-amplified HDV and HBV fragments showed exclusively HDV genotype III and HBV genotype F. Furthermore, HDV RNA sequences were similar among patients from the same outpost but different from those at other jungle locations. The data suggested focal sources of HDV infection in the jungle environment of the outposts and, further, confirmed the unique association of HDV genotype III with severe cases of human disease in northern South America. [ABSTRACT FROM AUTHOR]
- Published
- 1996
- Full Text
- View/download PDF
19. A black feminist exploration of the cultural experiences and identities of academically ‘successful’ British South-Asian girls
- Author
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Ludhra, Geeta, Watts, DM, Jones, D, and Evans, R
- Subjects
Religion ,Narrative ,Culture ,Secondary school ,Adolescent girls - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University London This study draws on a black feminist theoretical perspective, to develop an understanding of the cultural identities and experiences of twelve, academically 'successful', British South-Asian girls. The girls are aged between 16-18 years, and from Hindu, Sikh and Muslim religious backgrounds, selected across two West London secondary schools. A narrative interview approach is used to explore how these girls configure and invest in 'culture' and their cultural identities, during a critical stage in their academic lives before entering university. A series of unstructured interviews have been held with each girl, and these were complemented with reflective journals. The girls' narratives reveal how 'culture' (a contested term) is discussed with high weighting in relation to the importance of education, which they all narrated as an important key to unlocking 'success' in their future lives. The girls' identities move beyond media discourses that stereotype them as ‘passive’ and lacking a voice. These girls demonstrate agency and high aspirations for 'having it all', narrated through discourses of hard work, meritocracy and aspiration. This study reveals the complex interaction of experiences that influence South-Asian girls' cultural identities, and the interplay of structure and agency in their journeys towards becoming 'successful', irrespective of their largely working-class backgrounds. Whilst I recognise that all adolescents will face challenges of some kind, being a South-Asian girl embodies its own particularities, linked to markers of difference in 'culture', religion, gender, ethnicity, 'race', class, language, dress, amongst other historical influences. These differences are not necessarily embodied as negative forces by these girls, but rather, used as a catalyst for personal growth, where they draw on their psychological strength, aspirations and desires, to become 'successful' young women. This thesis makes a unique contribution to black feminist theory, girlhood studies, as well as narrative and educational literature. It acknowledges the uniqueness of South-Asian girls' cultural experiences and backgrounds, and challenges some of the cultural discourses in the media that pathologise them. It is written in a critically reflexive style, from the perspective of a second-generation, British-born, South-Asian academic, who, at the time of writing this thesis, was also raising two academically 'successful' daughters of her own. The inspiration for this research is rooted in the researcher's narratives of girlhood and early womanhood. Abstract This study draws on a black feminist theoretical perspective, to develop an understanding of the cultural identities and experiences of twelve, academically 'successful', British South-Asian girls. The girls are aged between 16-18 years, and from Hindu, Sikh and Muslim religious backgrounds, selected across two West London secondary schools. A narrative interview approach is used to explore how these girls configure and invest in 'culture' and their cultural identities, during a critical stage in their academic lives before entering university. A series of unstructured interviews have been held with each girl, and these were complemented with reflective journals. The girls' narratives reveal how 'culture' (a contested term) is discussed with high weighting in relation to the importance of education, which they all narrated as an important key to unlocking 'success' in their future lives. The girls' identities move beyond media discourses that stereotype them as ‘passive’ and lacking a voice. These girls demonstrate agency and high aspirations for 'having it all', narrated through discourses of hard work, meritocracy and aspiration. This study reveals the complex interaction of experiences that influence South-Asian girls' cultural identities, and the interplay of structure and agency in their journeys towards becoming 'successful', irrespective of their largely working-class backgrounds. Whilst I recognise that all adolescents will face challenges of some kind, being a South-Asian girl embodies its own particularities, linked to markers of difference in 'culture', religion, gender, ethnicity, 'race', class, language, dress, amongst other historical influences. These differences are not necessarily embodied as negative forces by these girls, but rather, used as a catalyst for personal growth, where they draw on their psychological strength, aspirations and desires, to become 'successful' young women. This thesis makes a unique contribution to black feminist theory, girlhood studies, as well as narrative and educational literature. It acknowledges the uniqueness of South-Asian girls' cultural experiences and backgrounds, and challenges some of the cultural discourses in the media that pathologise them. It is written in a critically reflexive style, from the perspective of a second-generation, British-born, South-Asian academic, who, at the time of writing this thesis, was also raising two academically 'successful' daughters of her own. The inspiration for this research is rooted in the researcher's narratives of girlhood and early womanhood.
- Published
- 2015
20. Family play-learning through informal education: Make and play activities with traditional Thai toy activities at a science museum
- Author
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Kanhadilok, Peeranut, Watts, DM, and Zwozdiak-Myers, P
- Subjects
Informal education ,Science museum ,Traditional Thai toy activity ,Make and play activity ,Family play-learning - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University This thesis charts the outcomes of family play-learning through make-and-play activities with traditional Thai toys activities (TTTA). Family learning is a component of inter-generational learning, and the research explores this through ‘edutainment’ activities within the informal educational system of a science museum. The thesis also identifies key factors that influence family play-learning through TTTA and explores the nature and impact of traditional Thai culture, local wisdom and Western modern science after participation with the TTTA. Participants in the toy-making activities at the National Science Museum, Thailand are members of the general public, day visitors to the museum who volunteer to join the activities, and represent all age groups. They also have varied levels of educational achievement, backgrounds in science and dispositions towards play. The research follows 93 families, including children, teenagers and adults, a total of 179 participants. Participants’ dispositions towards play are collected through self-reporting questionnaires based upon Barnett's (2006) work on playfulness; data on their individual and group actions have been collected in terms of their levels of enjoyment and engagement with the tasks, and learning outcomes. The data from structured routine observation indicates that, within the make-and-play activities, there is a two-way transfer of learning from older to younger, and from younger to older. The analysis of family learning is based upon Bandura’s (2005) social cognitive theories, used here in relation to informal museum education. Family play-learning is seen as significant, where more experienced members of the family transfer their knowledge and role-model skills to their children or younger members of the family. There is also an upward transfer where discerning youth model the fun and creativity they bring to the tasks. The Toy Learning Outcomes Questionnaire (TLOQ) has been used to study families’ learning outcomes from the TTTA with 51 families composed of 125 participants in total. The TLOQ is based upon work of the Research Centre of Museums and Galleries at the University of Leicester (Hooper-Greenhill, 2007), and uses a four-point Likert-style scale to explore seven areas of interest: (i) knowledge and understanding; (ii) skills; (iii) attitudes and values; (vi) enjoyment, inspiration and creativity; (v) action, behaviour and progression; (vi) scientific learning, and (vii) attitude towards Thai local wisdom. The findings show that families appear to have learned most in relation to two of these areas, ‘scientific knowledge’ and ‘Thai local wisdom’, when compared with the other areas. Data from semi-structured ‘exit interviews’ at the end of the activities, explore this clash of cultures, between Western modern science (WMS) and Thai local wisdom (TLW). This allows for a discussion of the integration of knowledge systems versus distinctive and separate fields. Findings from the interview data indicate that participants treat the TTTA, and work of the museum generally, bi-gnosically: they had positive yet parallel attitudes towards both domains of knowledge. The overall outcomes of this body of work indicate two main factors that encourage family play-learning: (i) the context of the play, which emphasises participants’ personal engagement, social relationships, and the physical setting (the environment and resources in the TTTA); and (ii) the conditions to play, playfulness of the participants and the opportunities they take to learn together through play. The thesis concludes with the implications of this work and recommendations for further research. Thai government, the National Science Museum, Thailand (NSM), Mr. Suchin Kanhadilok and Mrs Pim Kanhadilok, who have sponsored me to study for my doctoral degree at Brunel University
- Published
- 2013
21. Special Needs Education (SNE) in Kenyan public primary schools: exploring government policy and teachers’ understandings
- Author
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Mwangi, Lucy and Watts, DM
- Subjects
Special Educational Needs (SEN) ,Teachers' comprehensions ,SNE Framework ,Kenya - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. This research focuses on Special Needs Education (SNE) in Kenyan Public Primary Schools: Exploring Government Policy and Teachers’ understandings. At a time when Kenya is introducing reforms with a view to addressing broad national objectives and providing universal primary education (UPE) after the massive enrolment increases arising from the free primary education declaration (FPE), it was important to establish teachers’ understandings on SEN. The study was undertaken in 27 primary schools in urban, municipal and rural parts of Kenya. A phenomenological qualitative approach was mainly used and data were collected from teachers through a survey comprising: (i) 159 self-administered questionnaires ii) Nine in-depth interviews. From the results of a pilot study, necessary adaptations were made for the main study. The data provided insights to teachers’ teaching strategies, impacts of mainstreaming, factors that prevent the participation of children said to have SEN, challenges in meeting the diverse needs in the classroom and the support they may require in providing more engaging and effective learning instructions. The findings show that many teachers lack a repertoire of learning and teaching strategies appropriate for addressing barriers to learning and providing individualized approaches in the classrooms. Some teachers were positive about teaching children said to have SEN but lacked the infrastructure of support and guidance, were confused by different terminologies and found the concept of SEN not to be enabling. What teachers are calling for is more training to help them develop strategies which are responsive to the identified learning difficulties. Through Documentary Analysis of the Kenya National Special Needs Education (SNE) Policy Framework, Ministry of Education (MoE, 2009), it was identified that the policy is difficult and ambiguous for teachers to implement. The policy fails to include salient definitions to facilitate a common way of addressing children said to have SEN which results in them being labelled. The recommendations of the research indicate that children’s unique needs be made transparent and addressed using effective individualized education plans to influence and maintain high expectations, positive and enriched ways of teaching in order to improve the children’s learning opportunities as well as other extracurricular activities. The national policy should be revised to include feasible targets in order to facilitate on-going evaluation and embed definitions of key words which are pivotal to planning, assessment, identification, provision and placement of children said to have SEN. Suggestions for further research have also been included.
- Published
- 2013
22. The impact of blended learning on female student-teachers in Kuwait
- Author
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Ghaith, Omar, Watts, DM, and Collins, S
- Subjects
Personal learning environment (PLE) ,Education in Kuwait ,Virtual learning environment (VLE) ,ComputingMilieux_COMPUTERSANDEDUCATION ,ADDIE Model - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. This study aims to identify the effect of using the blended learning method on students' academic achievement and satisfaction level in a university course for female student teachers who follow the General Teaching Method Course (304) at the College of Basic Education in Kuwait. The content of the course (304) was based on the five stages of the ADDIE instructional design model, comprising five phases: (1) Analysis, (2) Design, (3) Development, (4) Implementation, and (5) Evaluation. The research questions of the study can be summarised in two main questions: 1. What is the effect of using the method of blended learning in the General Teaching Method Course (304) on students’ academic achievement, compared to using face–to–face approaches to learning alone? 2. What is the effect of using the method of blended learning in the General Teaching Method Course (304) on students’ satisfaction, compared to using face–to-face approaches to learning alone? The researcher answered these questions through a mixed method research approach using the Explanatory Sequential Design, in order to determine the nature and objectives of the study. In this, the researcher started with the collection and analysis of quantitative data (using a quasi-experimental approach), which has priority for addressing the two research questions, and then followed this with the collection and analysis of qualitative data (using group interviews) to help explain the quantitative results. The researcher identified the study sample as 96 female students’ teachers at the College of Basic Education in Kuwait. The sample consisted of a first experimental group (n= 39)who followed the General Teaching Method Course (304) by blended learning using virtual learning environment (VLE) of Blackboard, a second experimental group (n=31) who followed the course (304) by blended learning using personal learning environment (PLE) of Facebook, and the control group (n= 26) who followed the course (304) using face-to-face approaches to learning alone. The dependent variables were academic achievement (as assessed in the course’s midterm, final and practical exams) and students’ satisfaction (as assessed by the questionnaire, giving a total mark and 3 sub-marks in reference to the students’ satisfaction about the teaching method of the course, the content of the course, and the instructor's support during the course). When answering the first question of the research, the study found that there was a significant difference in both mid-term and final tests between the first experimental group (studying through the blended learning method using VLE of Blackboard) and the control group (studying through face-to-face learning alone). However, there was no significant difference in both mid-term and final tests between the second experimental group (studying through the blended learning method using PLE of Facebook) and the control group. And there was also no significant difference in the practical test between the two experimental groups (each separately) and the control group. When answering the second question of the research, the study found that there was a significant difference in the teaching method dimension of the satisfaction questionnaire between the two experimental groups (each separately) and the control group. And there was also a significant difference in the instructor’s support dimension of the satisfaction questionnaire between the first experimental group and the control group, but no significant difference was found between the second experimental group and the control group. There was also no significant difference in the course content dimension of the satisfaction questionnaire between the two experimental groups (each separately) and the control group.
- Published
- 2013
23. Buffering preconscious stressor appraisal: the protective role of self-efficacy
- Author
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Filtness, Timothy William, Bishop, D, Gonzalez-Alonso, J, and Watts, DM
- Subjects
Emotion ,Automatic ,Implicit appraisal ,Implicit association test ,Stress - Abstract
This thesis was submitted for the degree of Doctor of Education and awarded by Brunel University. Many cognitive resources contribute towards the appraisal of stressors. Of these, self-efficacy (SE) is widely acknowledged to play a significant role in protecting adolescents from the effects of stress (Bandura, 1997). This study investigated that relationship through the use of a quasi-experimental methodology (Cook & Campbell, 1979) utilising an untreated Control group of 44 adolescent, female participants and an Experimental group of 70 additional participants, all of whom were volunteers drawn from the Sixth Form of a single participating school. The members of both participant groups took part in two rounds of testing, between which the members of the Experimental group were exposed to a significant academic stressor (one or more public A-level examinations). During both test phases, all participants completed the 10- item Perceived Stress Scale self-report (Cohen & Williamson, 1988), the Examination Self-Efficacy Scale instrument (Schwarzer & Jerusalem, 1995) and a bespoke Implicit Association Test (Greenwald et al., 1998) designed to measure implicit stressor appraisal. Significant trends were identified by means of ANCOVA, correlation and regression analyses, and the resulting data were interpreted in terms of a dual process model of stress (Compas, 2004). Results not only concurred with those of previous studies (e.g. Betoret, 2006; Vaezi & Fallah, 2011) by demonstrating a strongly negative correlation between acute academic stress and academic SE, but provided new evidence to suggest that the ‘protective’ effect of SE occurs via a buffering mechanism at the level of preconscious stressor appraisals (Bargh, 1990), which limits the effect of acute stress exposure on preconscious stressor appraisals (e.g. Luecken & Appelhans, 2005).
- Published
- 2013
24. From composition to transcription: A study of conceptual understanding and levels of awareness in thinking used by children during specific genre writing tasks
- Author
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Silby, Alison and Watts, DM
- Subjects
Writing ,Genres ,Awareness ,Children ,Collaborative - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. This naturalistic study of cases explores the interrelationship between children’s awareness of their own thought processes, their ability to understand key concepts and concept vocabulary and integrate new ideas into their existing knowledge base when engaged in specific genre writing tasks. An adaptation of the framework, originally devised by Swartz and Perkins (1989), was used to identify the levels of awareness in thinking displayed by eight Year 3 children, when engaged in genre writing tasks during one academic year. The addition of ‘collaborative use’ to this framework highlights ways in which collaborative thinking can act as a support for young writers. When children co-construct ideas they endeavour to make their thinking explicit thus enabling teachers to assess levels of conceptual understanding whilst the children are engaged in a writing task. Evidence also suggests that young writers move in and out of the suggested levels of thinking depending on the complexity of the task, their prior knowledge and understanding of key concepts and awareness of the working strategies and thought processes they employ. This study not only contributes to current research on genre writing within school based contexts but makes a unique contribution by highlighting the need for pedagogical strategies to focus on the way young writers think about and understand the underlying concepts and principles related to genre writing tasks. Evidence also suggests that learning objectives presented to this age group often focus on the factual and procedural aspects of a writing task. However, when factual, procedural and conceptual aspects are made explicit through clear, thought-provoking learning objectives then children are able to develop their own creative responses within the linguistic and textual structures of the given genre without being confined by them.
- Published
- 2013
25. A comparative study between Kuwait’s Government and Private Sector Primary Schools in methods of teaching and pupils’ achievement in mathematics
- Author
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Al-Duwaila, Abdulrahman, Watts, DM, and Leslie, D
- Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The study aimed at identify the aspects associated with teaching mathematics and students’ learning through The framework for the scientific and theoretical features and properties related to: a) teaching mathematics in primary school, b) mathematics students' achievement and educational environment attributes, schools and teachers, c) nature of primary education in private and governmental schools, d) The differences between them in Kuwait in light of fifth primary class teaching methods and skills, and student learning and factors that affect it. Study sample included (20) mathematics teachers, all of whom taught fifth grade pupils from three primary schools in Kuwait (one private and two public; one for boys and the other for girls). Of these twenty, (10) were mathematics teachers in public primary schools and the other (10) were in the private primary school. Also, a sample of (80) pupils were chosen from fifth grade primary consisting of (50) pupils from the public schools (25 boys and 25 girls) and the remaining (30) pupils from the private schools (15 boys and 15 girls). Many tools were administered: a) a pilot study to define the problem and confirm the validity of the research questions ;b) questionnaire for teachers to elicit information concerning the teaching methods employed; c) Collation of pupils’ achievement data to define and discover the differences between pupils’ achievement. A number of statistical tools from the SPSS package for analysing social research data were used, the most important of which were: Cronbach's Alpha; Frequencies and percentages; and T test. Result showed that there are statistical differences between the government and private schools concerning: the attributes and characteristics of the methods of teaching mathematics; the mathematics curriculum; the components of the educational and scholastic environment; and the students' achievement. there are no statistical differences between the government and private schools concerning: the teacher's perception of student's achievement; and the teacher's skills.
- Published
- 2012
26. A suggested programme for developing 4th year primary pupils’ performance in Mathematical word problems in Kuwait
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Almansouri, Meshal B, Watts, DM, and Leslie, D
- Subjects
Mathematics anxiety ,Teaching factors ,education ,Mathematics teaching ,Arab countries ,Kuwait education - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The main objective of this study was to investigate the effect of using a suggested mathematical word-problem training programme on Primary 4 pupils' performance in mathematical word-problems. The study had a pre-post control group design. A treatment and a no-treatment group were exposed to pre-post methods of gathering data (a mathematical word-problem achievement test and a mathematical word-problem attitude scale). The treatment group was given direct and explicit training on how to solve mathematical word-problems, while the pupils of the no-treatment group received no such training; they were taught the same material they study at school. A "t" test was used to compare the means of scores of the control group pupils and those of the experimental group in the pre-post measurements. Results of the study revealed a significant improvement in the experimental group pupils’ performance in mathematical word-problems because they had attended the suggested programme. Results also revealed that experimental group subjects' attitudes towards mathematical word-problems underwent an exceptional change because they had attended the suggested programme. Their attitudes towards mathematical word-problems became more positive than before. In the light of the results of the study, some recommendations were made for improving mathematics teacher training programmes, for mathematics teaching, and for further research.
- Published
- 2011
27. Reflecting blues - Perceptions of policing students undertaking a Preparing to Teach in the Lifelong Learning Sector (PTLLS) course with regard to reflective practice and associated skills
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Malthouse, Richard and Watts, DM
- Subjects
Reflective practice ,Policing students ,Situated reflective practice ,PTLLS ,Preparing to teach in the lifelong learning sector - Abstract
This thesis was submitted for the degree of Education Doctorate and awarded by Brunel University. This research considered the perceptions of policing students who attended a Preparing to Teaching in the Lifelong Learning Sector (PTLLS) course at a Central London College for Further Education, in relation to their study needs, motivation levels, relevant support and reflective practice. This phenomenological study considered 15 students from the Metropolitan Police Service (MPS) employing the use of semi-structured interviews to gather data. The findings were that the students‟ perception in relation to the support offered by the MPS was insufficient and this may be due to the pedagogical approach to learning favoured by many students. Several appeared to require support with learning and writing level at three or four. The college did very well in respect of the perception of the students in relation to the support they experienced. The scarcity of time and the intensity of the course was a prominent factor, where some had underestimated how much time they would need to allocate to study. Overwhelmingly the students required support when engaging in study at level three or four and there appeared to exist very little knowledge in how to write an assignment. Some of the students appeared to favour a more pedagogical approach to study and in some cases reacted against the andragogical style employed by the college. Support from the mentor was valued considerably by most of the students and this appears to be a contributory factor in easing the students back into study. In relation to students‟ perceptions of Reflective Practice (RP) there existed three distinct groups, namely those who considered that they used reflective practice, those who considered they did on certain occasions and one who did not. In general there existed a positive attitude towards the concept of RP although none of the students kept a record of their subsequent RP following the PTLLS course. The phenomenon of Situational Reflective Practice was observed which took the form of Reflection-re-Action and Reflection-re-Inaction. This is concerned with the way in which a social group or an organisation is behaving and the impact this has upon an individual. Further research in relation to the idea of Situational Reflective Practice is called for.
- Published
- 2011
28. The impact of computer use in the development of Mathematics teaching in primary education
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Alawadhi, Nabil and Watts, DM
- Subjects
Technology teaching ,Teacher training and practice ,Kuwait educational system ,ComputingMilieux_COMPUTERSANDEDUCATION ,Constructionism ,Mathematics curriculum reform - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. The educational system in Kuwait is intended to provide primary and secondary students with required skills in order to operate in the technical careers commonly undertaken. However, mathematics education lags significantly behind other countries in Kuwait. In the 1997 and 2008 TIMMS international studies of primary and secondary mathematics achievement, Kuwait ranked near the bottom on almost all scores. Thus, improving mathematics education in Kuwait is an issue of serious concern. This research focuses on the question of whether mathematics teaching and learning in Kuwaiti primary schools (grade 4) can be improved through the use of computer-based tools for practice drills and constructive mathematics play. An observational intervention was used in a classroom of 24 children, where students took a pre-test for mathematics achievement, then engaged in a series of exercises through the term and were retested at the end of the term. This was accompanied by a series of in-services and teacher interviews that were conducted within the school, in order to discover attitudes about mathematics teaching and learning and to train teachers in the suggested approaches and techniques. A combined qualitative and quantitative approach included analysis of test scores and interviews with teachers and students. The overall outcomes of the study did show a slight increase in mathematics achievement scores. However, more importantly it showed an improvement in children’s and teacher’s attitudes to mathematics learning related to the introduction of constructive play activities (derived from the Cambridge University N-RICH program and selected for students based on level of achievement) Overall, the importance of this study is that it provides pragmatic information for Kuwaiti teachers and curriculum designers on improving mathematics teaching and learning.
- Published
- 2011
29. An exploration of African-Caribbean boys’ underachievement and their stories of schooling
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Graham, Janet, Watts, DM, and Hebron, J
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Boys ,education ,Underachievement ,Exclusion ,Subculture ,Institutianalised racism - Abstract
This thesis was submitted for the degree of Doctor of Education and awarded by Brunel University. This study investigates why African-Caribbean boys continue to underachieve in schools. It is based on an extensive study of one Inner London school and has also involved a thorough review of the existing literature about why this particular group of students do not fulfil their potential. The inspiration for this study has been the work of Bernard Coard (1971) who wrote influentially about how the first generation of West Indian children was branded as ‘Educationally Subnormal’ by the British school system. Over thirty years later, the failure of African-Caribbean boys continues to be an alarming phenomenon, despite years of multi-culturalism and education for ‘diversity’. One of the arguments of my study is that African-Caribbean boys can even become ‘hidden’ amongst much larger groups of students who have English as an Additional Language (EAL) and who as a result, often receive extensive additional support. British schools have changed since the time that Coard (1971) was writing, but as my study demonstrates African-Caribbean boys are still likely to be over represented in the various Behaviour or Learning Support Units. I have also discovered that, far fewer African-Caribbean boys in the school investigated are likely to go on to the sixth form in comparison to students from other backgrounds. Even though there have been many studies about race and education, far fewer researchers have tried to ‘hear it from the boys’. I have carried out extensive research at school level amongst the boys and their teachers. As well as conducting an Institutional Focus Study of the school in question. I have argued that, whilst other groups such as white working class boys have been hostile to school, on the contrary, most of the boys in my study wanted to learn or saw the importance of obtaining qualifications in order to improve their chances in life. African-Caribbean boys are not ‘their own worst enemies’, but the reasons for their underachievement are complex, being the result of a range of factors. As I am a practitioner, I have concluded my study with some practical proposals for change which I hope will make a difference to the lives of these boys.
- Published
- 2011
30. Factors affecting the choice of science subjects among girls at secondary level in Mauritius
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Naugah, Jayantee, Reiss, M, and Watts, DM
- Subjects
Self-identities ,Scientific literacy ,Socio-cultural ,Gender ,Pedagogical clash - Abstract
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. This research attempts to identify the factors which influence the choice of science subjects in Mauritius among girls at the end of the third year of secondary education, the level up to which science is a compulsory subject. This low uptake of science subjects by girls beyond the compulsory level is a matter of concern. The study was undertaken in four purposely selected schools in Mauritius, two mixed-sex and two girls’ schools. Using mainly a qualitative approach, data were collected through: (i) non-participant observations of 60 science and 20 non-science lessons, (ii) 16 semi-structured face-to-face interviews of teachers, and six group interviews with pupils and (iii) 135 questionnaires administered to the parents of the pupils in the classes observed in the four schools. Based on the results of a pilot study, modifications were made for the main study. The data provided insights into teachers’ teaching approaches, the behaviour and interest of pupils in the lessons and other factors such as pupils’ perceptions of science, their self-identity and role models, and the extent to which parents and peers influence the choice of subjects among girls. The findings show that teaching approaches were mainly traditional and that both girls and boys prefer hands-on activities and contextual examples reflecting real-life situations. The majority of the girls’ experiences of science were negative and this deterred them from taking science beyond the compulsory level although they were aware of its importance. Teachers had positive opinions about girls’ ability to do science but stated that lack of infrastructure facilities did not allow them to involve the pupils in practical work as much as they would wish. However, brighter girls’ decisions to study sciences were not outweighed by these factors. Parents felt that they did not influence their daughters in the choice of subjects or eventual careers though they held science in high esteem.
- Published
- 2011
31. Aedes aegypti oviposition in urban communities in the Northern Chihuahuan Desert.
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Vera AJ, Soliz AG, Mora-Covarrubias A, and Watts DM
- Abstract
Background Objectives: Aedes aegypti (Linnaeus) is the vector of multiple arboviruses, the most important being dengue viruses (DENV) that causes more than 90 million cases per year. The expanded range of Ae. aegypti into temperate climates has contributed to the increasing risk of DENV to new human populations. As an effort to better understand the ecology of Ae. aegypti in a temperate climate, larval surveillance was conducted to identify oviposition locations of this species from 2016-2018 in two nonincorporated communities located in El Paso, Texas and Ciudad Juárez, Chihuahua, Mexico., Methods: This survey was conducted inside and outside private residences examining any possible water holding containers to collect with a dipper, turkey baster, or Pasteur pipette. Larvae and pupae were transported to the laboratory and reared to adults for morphological identification. A total of 601 Ae. aegypti larvae were collected and reared to adults from 24 containers in the Sparks community. In contrast, a total of 68 Ae. aegypti were collected and reared to adults from seven containers in the Anapra community., Results: In both locations, the predominant container type that yielded immature mosquitoes were plastic buckets. Although the results were based on a small sample size, the finding provided a preliminary understanding of the oviposition sites of Ae. aegypti in two urban communities in a temperate climate region., Interpretation Conclusion: The identification of oviposition sites can be used to develop and implement vector control strategies., (Copyright © 2024 Copyright: © 2024 Journal of Vector Borne Diseases.)
- Published
- 2024
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32. Genomic Analysis of Aedes aegypti in the Northern Chihuahuan Desert of Texas and Mexico.
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Vera AJ, Soliz AG, Khatchikian CE, de la Mora-Covarrubias A, Watts DM, and Lavretsky P
- Abstract
Background: Aedes aegypti, is the primary vector of dengue, Chikungunya, Zika, and yellow fever viruses. Both natural and human-impacted landscapes have selective pressures on Ae. aegypti, resulting in strong genomic structure even within close geographical distances. Materials and Methods: We assess the genetic structure of this medically important mosquito species at the northern leading edge of their distribution in Southwestern USA. Ae. aegypti were collected during 2017 in the urban communities of El Paso and Sparks, Texas (USA) and in the city of Ciudad Juárez, Mexico. Results: Thousands of nuclear loci were sequenced across 260 captured Ae. aegypti. First, we recovered the genetic structure of Ae. aegypti following geography, with all four major collection communities being genetically distinct. Importantly, we found population structure and genetic diversity that suggest rapid expansion through active-short distance dispersals, with Anapra being the likely source for the others. Next, tests of selection recovered eight functional genes across six outliers: calmodulin with olfactory receptor function; the protein superfamily C-type lectin with function in mosquito immune system and development; and TATA box binding protein with function in gene regulation. Conclusion: Despite these populations being documented in the early 2000s, we find that selective pressures on specific genes have already occurred and likely facilitate Ae. aegypti range expansion.
- Published
- 2024
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33. Evidence of SARS-CoV-2 Antibody in Mississippi White-Tailed Deer.
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Hearst S, Palermo PM, Watts DM, Campbell K, Ivey R, Young C, Yarbrough W, Facundus E, Spears J, Mills S, McNeely KA, Ray P, Burnett GC, Bates GT, and Bates JT
- Abstract
Background: Early detection and monitoring of SARS-CoV-2 infections in animal populations living in close proximity to humans is crucial for preventing reverse zoonosis of new viral strains. Evidence accumulated has revealed widespread SARS-CoV-2 infection among white-tailed deer (WTD), ( Odocoileus virginianus ) populations in the United States except in the southeast region. Therefore, the objective was to conduct surveillance for evidence of SARS-CoV-2 infection among WTD in Mississippi. Materials and Methods: Blood, kidney tissues, and nasal swab samples were collected in 17 counties from hunter-harvested deer during 2021-2022 and 2022-2023.Samples of kidney tissue were collected to evaluate for detecting antibody as a possible alternative to blood that is not always available from dead WTD. Nasal swab samples were tested for SARS-CoV-2 viral RNA by a RT-PCR assay. Sera and kidney tissue samples were tested for SARS-CoV-2 antibody by an enzyme-linked immunoassay (ELISA) and sera by a plaque reduction neutralization test (PRNT
80 ). Results: The results of testing sera and kidney homogenate samples provided the first evidence of SARS-CoV-2 infection among WTD in Mississippi. The infection rate during 2021-2022 was 67% (10/15) based on the detection of neutralizing antibody by the PRNT80 and 26%(16/62) based on the testing of kidney tissue homogenates by an ELISA, and viral RNA was detected in 25% (3/12) of nasal swab samples. In 2022 to 2023, neutralizing antibody was detected in 62% (28/45) of WTD serum samples. In contrast, antibodies were not detected in 220 kidney homogenates by an ELISA nor was viral RNA detected in 220 nasal swab samples. Evidence of WTD activity was common in urban areas during the survey. Conclusion: Overall, the findings documented the first SARS-CoV-2 infection among WTD in Mississippi and showed that WTD commonly inhabited urban areas as a possible source of acquiring infection from humans infected with this virus.- Published
- 2024
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34. Evaluation of a Combined Live Attenuated Vaccine against Lumpy Skin Disease, Contagious Bovine Pleuropneumonia and Rift Valley Fever.
- Author
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Bamouh Z, Elarkam A, Elmejdoub S, Hamdi J, Boumart Z, Smith G, Suderman M, Teffera M, Wesonga H, Wilson S, Watts DM, Babiuk S, Pickering B, and Elharrak M
- Abstract
The use of effective vaccines is among the most important strategies for the prevention and progressive control of transboundary infectious animal diseases. However, the use of vaccine is often impeded by the cost, a lack of cold chains and other factors. In resource-limited countries in Africa, one approach to improve coverage and reduce cost is to vaccinate against multiple diseases using combined vaccines. Therefore, the objective of this study was to evaluate a combined vaccine for the prevention and control of Lumpy Skin Disease (LSD), Contagious Bovine Pleuropneumonia (CBPP) and Rift Valley fever (RVF). The LSD and CBPP were formulated as a combined vaccine, and the RVF was formulated separately as live attenuated vaccines. These consisted of a Mycoplasma MmmSC T1/44 strain that was propagated in Hayflick-modified medium, RVF virus vaccine, C13T strain prepared in African green monkey cells (Vero), and the LSDV Neethling vaccine strain prepared in primary testis cells. The vaccines were tested for safety via the subcutaneous route in both young calves and pregnant heifers with no side effect, abortion or teratogenicity. The vaccination of calves induced seroconversions for all three vaccines starting from day 7 post-vaccination (PV), with rates of 50% for LSD, 70% for CBPP and 100% for RVF, or rates similar to those obtained with monovalent vaccines. The challenge of cattle vaccinated with the LSD/CBPP and the RVF vaccine afforded full protection against virulent strains of LSDV and RVFV. A satisfactory level of protection against a CBPP challenge was observed, with 50% of protection at 6 months and 81% at 13 months PV. A mass vaccination trial was performed in four regions of Burkina Faso that confirmed safety and specific antibody responses induced by the vaccines. The multivalent LSD/CBPP+RVF vaccine provides a novel and beneficial approach to the control of the three diseases through one intervention and, therefore, reduces the cost and improves vaccination coverage.
- Published
- 2024
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35. Serosurveillance for Severe Acute Respiratory Syndrome Coronavirus 2 Antibody in Feral Swine and White-Tailed Deer in Texas.
- Author
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Palermo PM, Orbegozo J, Watts DM, and Morrill JC
- Subjects
- Chlorocebus aethiops, Animals, Swine, Texas epidemiology, SARS-CoV-2, Vero Cells, Antibodies, Viral, Antibodies, Neutralizing, Deer, COVID-19 epidemiology, COVID-19 veterinary, Swine Diseases epidemiology
- Abstract
Background: Serological evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been reported in white-tailed deer (WTD) in the United States and Canada. Even though WTD are susceptible to SARS-CoV-2 infection, there is no evidence of infection by this virus in other mammalian species that might interact with WTD in nature. Similar to WTD, feral swine are widely distributed and generally occupy the same range as WTD in Texas. The objective of this study was to determine the prevalence of SARS-CoV-2 neutralizing antibody in WTD during 2020 and 2021 and determine the prevalence of SARS-CoV-2 neutralizing antibody in feral swine during 2018 (prepandemic period) and from March 2020 to February 2021 (pandemic period) in Travis County, Texas. Materials and Methods: Sera samples were collected from hunter-killed WTD and feral swine during the prepandemic and pandemic period and tested for SARS-CoV-2 antibody by a plaque reduction neutralization assay in Vero cells. Results: SARS-CoV-2 antibody was not detected in any of the 166 feral swine sera samples, including 24 samples collected during the prepandemic and 142 samples collected during the pandemic period. Furthermore, SARS-CoV-2 antibody was not detected in the 115 WTD samples collected during late 2020, but antibody was detected in WTD in early 2021. Conclusions: The results indicated that SARS-CoV-2 infection of WTD occurred during early 2021 in Travis County, Texas, but serological evidence of SARS-CoV-2 infection was not detected in the feral swine samples collected from the same locality and during the same time period of the collection of WTD samples.
- Published
- 2023
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36. Rift Valley fever MP-12 vaccine elicits an early protective immune response in mice.
- Author
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Morrill JC, Peters CJ, Bettinger GE, Palermo PM, Smith DR, and Watts DM
- Subjects
- Humans, Mice, Animals, Antibodies, Neutralizing, Antibodies, Viral, Immunity, Rift Valley Fever prevention & control, Rift Valley fever virus, Culicidae
- Abstract
Rift Valley fever virus (RVFV) is an important mosquito-borne pathogen that causes outbreaks of severe disease in people and livestock throughout Africa and the Arabian Peninsula. The development of an effective veterinary and human vaccine to protect against Rift Valley fever (RVF) disease remains a high priority. The live attenuated RVFV MP-12 is a promising vaccine candidate for the prevention of RVF in both human and domestic ruminants. The aim of this study was to determine the onset of protective immunity elicted in mice by a single dose of this vaccine. Groups of CD-1 mice were vaccinated intraperitoneally with RVFV MP-12 vaccine and challenged on days 2, 5, 6 and 7 post-vaccination (PV) with a lethal dose of virulent RVFV. The mice were observed once daily for terminal morbidity and blood samples were obtained from the retro-orbital sinus complex on days 23 and 28 PV of surviving mice to determine RVFV neutralizing antibody titers. In one test, 2 of 3 mice challenged on day 2 PV survived and all 3 mice challenged at days 5 and 7 PV also survived. A second test of 10 mice per group was performed, and half (5) of those challenged at day 2 PV survived while all (10) survived challenge at day 4 and 6 PV. All surviving animals develop antibody that ranged from 1:80 to 1:1,280 PV. In a separate experiment, RVFV MP-12 vaccinated CD-1 mice, but not challenged developed a low viremia for the first 3 days PV and neutralzing antibody was detected on days 5 through day 28 PV. These findings demonstrated that the RVFV MP-12 vaccine elicited a rapid protective immune response in mice as early as 2 days PV, thus further supporting the effectiveness of this vaccine candidate for preventing RVF among humans and domestic ruminants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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37. Attenuation and genetic characteristics of a Moroccan strain of Camel pox virus.
- Author
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Bamouh Z, Hamdi J, Elkarhat Z, Fellahi S, Omari Tadlaoui K, Watts DM, Fassi Fihri O, and Elharrak M
- Subjects
- Chlorocebus aethiops, Animals, Camelus, Vero Cells, Antibodies, Neutralizing, Serial Passage, Vaccines, Attenuated, Poxviridae, Viral Vaccines
- Abstract
Camel pox (CML) is a widespread infectious viral disease of camels that causes huge economic losses to the camel industry. In this study, a local strain of Camel pox virus (CMLV) was attenuated by 175 serial passages in Vero cells and the residual pathogenicity and infectivity were tested in naïve camels at 120, 150 and 175 passage levels. Also, the safety and immunogenicity of the 175th passage were evaluated in camels using a dose of 10
4.0 Tissue Culture Dose 50% (TCID50) and monitored for up to one-year post vaccination (pv) for neutralizing antibody. Seroconversion was noted at day 14 pv with neutralizing antibody titers ranging from 0.5 and 1.6 logs over the one-year of the study. Among 8 camels inoculated with the P175 strain, 4 were challenged at 12-month pv with 105.7 TCID50 /ml of the original virulent CMLV and complete protection was recorded in all animals. Whole genome sequencing detected six mutations in the original CMLV strain that were not present in the attenuated 175th passage of this strain. Overall, the findings of this study indicated that the 175th passage of the CMLV was attenuated, safe and afforded protection to camels against virulent CMLV, and is therefore, a promising vaccine candidate for the prevention of CML in camels., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)- Published
- 2022
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38. Etiologies of Acute Undifferentiated Febrile Illnesses in and near Iquitos from 1993 to 1999 in the Amazon River Basin of Peru.
- Author
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Watts DM, Russell KL, Wooster MT, Sharp TW, Morrison AC, Kochel TJ, Bautista CT, Block K, Guevara C, Aguilar P, Palermo PM, Calampa C, Porter KR, Hayes CG, Weaver SC, de Rosa AT, Vinetz JM, Shope RE, Gotuzzo E, Guzman H, and Tesh RB
- Subjects
- Humans, Peru epidemiology, Rivers, Fever epidemiology, Encephalitis Virus, Venezuelan Equine, Arboviruses, Leptospirosis epidemiology, Malaria
- Abstract
The objective of this study was to determine the etiology of febrile illnesses among patients from October 1, 1993 through September 30, 1999, in the urban community of Iquitos in the Amazon River Basin of Peru. Epidemiological and clinical data as well as blood samples were obtained from consenting patients at hospitals, health clinics and private residences. Samples were tested for arboviruses in cell cultures and for IgM and IgG antibodies by ELISA. Blood smears were examined for malaria, and sera were tested for antibodies to Leptospira spp. by ELISA and microscopic agglutination. Among 6,607 febrile patients studied, dengue viruses caused 14.6% of the cases, and Venezuelan equine encephalitis virus caused 2.5%, Oropouche virus 1.0%, Mayaro virus 0.4%, and other arboviruses caused 0.2% of the cases. Also, 22.9% of 4,844 patients tested were positive for malaria, and of 400 samples tested, 9% had evidence of acute leptospirosis. Although the study was not designed to assess the importance of these pathogens as a cause of human morbidity in the total population, these results indicate that arboviruses, leptospirosis, and malaria were the cause of approximately 50% of the febrile cases. Although the arboviruses that were diagnosed can produce asymptomatic infections, our findings increased the overall understanding of the relative health burden of these infections, as well as baseline knowledge needed for designing and implementing further studies to better assess the health impact and threat of these pathogens in the Amazon Basin of Peru.
- Published
- 2022
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39. Estimation of the Minimal Rift Valley Fever Virus Protective Neutralizing Antibody Titer in Human Volunteers Immunized with MP-12 Vaccine Based on Protection in a Mouse Model of Disease.
- Author
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Watts DM, Westover JLB, Palermo PM, Bailey KW, Morrill JC, Bettinger GE, Monath TP, Smith DR, Peters CJ, Pittman PR, Orbegozo J, and Gowen BB
- Subjects
- Mice, Humans, Animals, Healthy Volunteers, Vaccines, Attenuated, Antibodies, Viral, Antibodies, Neutralizing, Mice, Inbred BALB C, Disease Models, Animal, Rift Valley fever virus, Rift Valley Fever, Viral Vaccines
- Abstract
The Rift Valley fever virus (RVFV) MP-12 vaccine is a promising human and veterinary vaccine. Although the vaccine elicited neutralizing antibody (nAb) in human volunteers, the minimal antibody titer that is needed to afford protection is unknown. Therefore, this study was conducted to determine the minimal nAb titer elicited by the RVFV MP-12 vaccine in human volunteers that protected mice against lethal RVFV challenge as a surrogate assessment of the protective efficacy of the vaccine. Among volunteers who were vaccinated with the MP-12 vaccine during a phase II trial, sera with antibody titers of 1:20 collected 5 years post-vaccination (PV), 1:40 titer collected 2 years PV, and 1:80 titer collected 1 year PV was passively transferred to groups of BALB/c mice. Blood samples were obtained 1 day after passive transfer to determine the RVFV neutralizing nAb titer before challenge with pathogenic RVFV (strain ZH501). Our results indicated that 1 day after passive transfer of the immune sera, an approximate 4-fold reduction in circulating nAb titers was detected in the mice. The presence of RVFV nAb titers in the range of 1:5 to 1:20 were generally protective (75-100% survival). These results suggested that circulating titers of 1:5 or higher offer a high degree of protection by MP-12-elicited antibody in human volunteers. Also, the findings highlighted the value of using the BALB/c mouse RVFV challenge model as a surrogate for evaluating the protective nAb responses elicited by MP-12 and possible use for evaluating the efficacy of other RVFV vaccine candidates.
- Published
- 2022
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40. A Branched and Double Alpha-Gal-Bearing Synthetic Neoglycoprotein as a Biomarker for Chagas Disease.
- Author
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Montoya AL, Carvajal EG, Ortega-Rodriguez U, Estevao IL, Ashmus RA, Jankuru SR, Portillo S, Ellis CC, Knight CD, Alonso-Padilla J, Izquierdo L, Pinazo MJ, Gascon J, Suarez V, Watts DM, Malo IR, Ramsey JM, Alarcón De Noya B, Noya O, Almeida IC, and Michael K
- Subjects
- Biomarkers, Humans, Mucins, Trisaccharides, Chagas Disease diagnosis, Chagas Disease drug therapy, Trypanosoma cruzi
- Abstract
Chagas disease (CD) is caused by the parasite Trypanosoma cruzi and affects 6-7 million people worldwide. The diagnosis is still challenging, due to extensive parasite diversity encompassing seven genotypes (TcI-VI and Tcbat) with diverse ecoepidemiological, biological, and pathological traits. Chemotherapeutic intervention is usually effective but associated with severe adverse events. The development of safer, more effective therapies is hampered by the lack of biomarker(s) (BMKs) for the early assessment of therapeutic outcomes. The mammal-dwelling trypomastigote parasite stage expresses glycosylphosphatidylinositol-anchored mucins (tGPI-MUC), whose O -glycans are mostly branched with terminal, nonreducing α-galactopyranosyl (α-Gal) glycotopes. These are absent in humans, and thus highly immunogenic and inducers of specific CD anti-α-Gal antibodies. In search for α-Gal-based BMKs, here we describe the synthesis of neoglycoprotein NGP11b, comprised of a carrier protein decorated with the branched trisaccharide Galα(1,2)[Galα(1,6)]Galβ. By chemiluminescent immunoassay using sera/plasma from chronic CD (CCD) patients from Venezuela and Mexico and healthy controls, NGP11b exhibited sensitivity and specificity similar to that of tGPI-MUC from genotype TcI, predominant in those countries. Preliminary evaluation of CCD patients subjected to chemotherapy showed a significant reduction in anti-α-Gal antibody reactivity to NGP11b. Our data indicated that NGP11b is a potential BMK for diagnosis and treatment assessment in CCD patients.
- Published
- 2022
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41. SARS-CoV-2 Neutralizing Antibodies in White-Tailed Deer from Texas.
- Author
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Palermo PM, Orbegozo J, Watts DM, and Morrill JC
- Subjects
- Animals, Antibodies, Neutralizing, Antibodies, Viral, Female, Male, SARS-CoV-2, Seroepidemiologic Studies, Texas epidemiology, COVID-19 veterinary, Deer
- Abstract
Serological evidence of SARS-CoV-2 infection among white-tailed deer has been reported from Illinois, Michigan, Pennsylvania, and New York. This study was conducted to determine whether deer in Texas also had evidence of SARS-CoV-2 infection. Archived sera samples collected from deer in Travis County, Texas, during 2018, before and during the pandemic in 2021 were tested for neutralizing antibody to this virus by a standard plaque reduction neutralization assay. SARS-CoV-2 antibody was not detected in 40 deer sera samples collected during 2018, but 37% (20/54) samples collected in 2021 were positive for antibody. The seroprevalence rate between males and females differed significantly ( p < 0.05) and the highest rate (82%) was detected in the 1.5-year-old animals. These findings extended the geographical range of prior SARS-CoV-2 infection among white-tailed deer in the United States and further confirm that infection was common among this species.
- Published
- 2022
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42. Evaluation of Two Serological Assays for Diagnosing Zika Virus Infection.
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Loyola S, Huaman A, Popuche D, Castillo E, Ampuero JS, Silva M, Guevara C, and Watts DM
- Abstract
Zika virus (ZIKV) emerged and spread rapidly in South American countries during 2015. Efforts to diagnose ZIKV infection using serological tools were challenging in dengue-endemic areas because of antigenic similarities between both viruses. Here, we assessed the performance of an in-house developed IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) and the plaque reduction neutralization test (PRNT) to diagnose ZIKV infection. Acute and convalescent paired serum samples from 51 patients who presented with clinical symptoms suggestive of an arbovirus illness in dengue-endemic areas of Honduras, Venezuela, Colombia and Peru were used in the assessment. Samples were tested for ZIKV, dengue and chikungunya virus using a variety of laboratory techniques. The results for the ZIKV-RNA screening and seroconversion detected by the microneutralization test were used to construct a composite reference standard. The overall sensitivity and specificity for the MAC-ELISA were 93.5% and 100.0%, respectively. Contrastingly, the overall sensitivity and specificity for the PRNT were 96.8% and 95.0%, respectively. Restricting the analysis according to IgM or neutralizing antibodies against dengue, the performances of both serological assays were adequate. The findings of this study reveal that the MAC-ELISA and PRNT would provide initial reliable laboratory diagnostic assays for ZIKV infection in dengue-endemic areas.
- Published
- 2021
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43. Characterization of a Dengue Virus Serotype 1 Isolated from a Patient in Ciudad Juarez, Mexico.
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Palermo PM, de la Mora-Covarrubias A, Orbegozo J, Plante JA, Plante KS, Jimenez-Vega F, and Watts DM
- Abstract
Dengue (DEN) is the most important human arboviral disease worldwide. Sporadic outbreaks of DEN have been reported since 1980 in urban communities located along the border in southeast Texas and northern Mexico. Other than the Rio Grande Valley region of TX, autochthonous transmission of DENV has not been reported from any other US border communities. As part of a surveillance program for arthropod-borne viruses in Ciudad Juarez, Mexico, during November 2015, a blood sample was obtained from a female patient who experienced an undifferentiated fever and arthralgia. The plasma of the sample was tested for virus in Vero-76 and C6/36 cells. DENV serotype 1 (DENV-1) was isolated in the C6/36 cells, and nucleotide sequencing of the envelope gene and full genome grouped the DENV-1 isolate in the Central America clade. The patient had not traveled outside of Ciudad Juarez, Mexico, thus suggesting DENV-1 infection was acquired in this community.
- Published
- 2021
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44. Surveillance of Trypanosoma cruzi infection in Triatomine vectors, feral dogs and cats, and wild animals in and around El Paso county, Texas, and New Mexico.
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Rodriguez F, Luna BS, Calderon O, Manriquez-Roman C, Amezcua-Winter K, Cedillo J, Garcia-Vazquez R, Tejeda IA, Romero A, Waldrup K, Watts DM, Khatchikian C, and Maldonado RA
- Subjects
- Animals, Animals, Wild parasitology, Cats, Chagas Disease epidemiology, Dogs, Feeding Behavior, Humans, Insect Vectors parasitology, Mammals, New Mexico epidemiology, Texas epidemiology, Chagas Disease veterinary, Triatoma parasitology, Trypanosoma cruzi isolation & purification
- Abstract
The causative agent of Chagas disease, Trypanosoma cruzi, is transmitted by triatomine vectors. The insect is endemic in the Americas, including the United States, where epidemiological studies are limited, particularly in the Southwestern region. Here, we have determined the prevalence of T. cruzi in triatomines, feral cats and dogs, and wild animals, the infecting parasite genotypes and the mammalian host bloodmeal sources of the triatomines at four different geographical sites in the U.S.-Mexico border, including El Paso County, Texas, and nearby cities in New Mexico. Using qualitative polymerase chain reaction to detect T. cruzi infections, we found 66.4% (n = 225) of triatomines, 45.3% (n = 95) of feral dogs, 39.2% (n = 24) of feral cats, and 71.4% (n = 7) of wild animals positive for T. cruzi. Over 95% of T. cruzi genotypes or discrete typing units (DTUs) identified were TcI and some TcIV. Furthermore, Triatoma rubida was the triatomine species most frequently (98.2%) collected in all samples analyzed. These findings suggest a high prevalence of T. cruzi infections among triatomines, and feral and wild animals in the studied sites. Therefore, our results underscore the urgent need for implementation of a systematic epidemiological surveillance program for T. cruzi infections in insect vectors, and feral and wild animals, and Chagas disease in the human population in the southwestern region of the United States., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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45. Enhancement of Zika virus infection by antibodies from West Nile virus seropositive individuals with no history of clinical infection.
- Author
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Garg H, Yeh R, Watts DM, Mehmetoglu-Gurbuz T, Resendes R, Parsons B, Gonzales F, and Joshi A
- Subjects
- Antibodies, Neutralizing immunology, Cross Reactions, Dengue Virus immunology, Female, Humans, Male, Middle Aged, Prevalence, Texas epidemiology, West Nile Fever epidemiology, West Nile Fever immunology, Zika Virus Infection immunology, Antibodies, Viral immunology, Antibody-Dependent Enhancement, West Nile virus immunology, Zika Virus immunology
- Abstract
Background: Recent outbreaks of Zika Virus (ZIKV) infection and associated microcephaly has raised multiple scientific questions. The close antigenic relatedness between flaviviruses makes diagnosis of specific infection difficult. This relatedness also raises the potential of Antibody Dependent Enhancement (ADE) via cross reactive antibodies to flaviviruses like West Nile Virus (WNV) and Dengue Virus (DENV). Asymptomatic WNV infections are endemic throughout the US creating a large proportion of the population that is seropositive for WNV antibodies. Whether these sero-positive individuals potentially carry ZIKV enhancing antibodies remains unknown., Results: Serum samples obtained from human subjects with symptomatic or asymptomatic WNV infection from a WNV endemic region in Texas were tested for their ability to enhance or neutralize ZIKV infection. Sero-surveillance data demonstrated a ~ 7% prevalence for WNV antibodies in the population. Sera from both symptomatic and asymptomatic WNV seropositive donors effectively neutralized WNV and to some extent DENV infection. Interestingly, WNV+ sera failed to inhibit ZIKV while significantly enhancing infection. Conversely, ZIKV specific sera effectively neutralized ZIKV, with ADE only evident at lower concentrations. The enhancement of ZIKV via WNV antibody positive sera was likely due to non-neutralizing Envelope (E) antibodies as seen with monoclonal ZIKV E antibodies., Conclusions: Overall, our findings suggest that WNV antibodies in the sera significantly enhance ZIKV infection in Fc receptor positive cells with limited neutralization activity. Further studies in more relevant models of ADE will be needed to confirm the relevance of these findings in vivo.
- Published
- 2021
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46. Serosurvey for dengue virus infection among pregnant women in the West Nile virus enzootic community of El Paso Texas.
- Author
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Watts DM, Rodriguez CM, Palermo PM, Suarez V, Wong SJ, Orbegozo J, Dupuis AP, Kramer LD, Gonzalez FJ, and Handel GA
- Subjects
- Dengue epidemiology, Dengue virology, Dengue Virus genetics, Enzyme-Linked Immunosorbent Assay methods, Female, Humans, Immunoglobulin G blood, Mexico epidemiology, Pregnancy, Pregnant Women, Serologic Tests, Texas epidemiology, West Nile virus genetics, Antibodies, Viral blood, Dengue blood, Dengue Virus pathogenicity, West Nile virus pathogenicity
- Abstract
All 4 dengue viruses (DENV) cause sporadic outbreaks of human disease in the Rio Grande Valley along the US-Mexico border. In addition, West Nile virus (WNV) is enzootic in most border communities, and is the only arbovirus known to cause human disease in the El Paso, Texas community. In an effort to determine if DENV were also endemic in the El Paso community, a serosurvey was conducted among mothers at the time of delivery of their babies in selected hospitals. Cord-blood plasma samples obtained from mothers were tested for DENV antibody by an enzyme-linked immuno-sorbent assay (ELISA), plaque reduction neutralization test (PRNT) and a multiplex microsphere immunoassay. All DENV antibody positive plasma samples were also tested for WNV antibody by the same assays to consider the possibility that DENV antibody positive samples reflected WNV cross reactive antibody. The results indicated that 0.74% (11/1,472) of the mothers had a previous DENV infection and that 3.3% (48/1,472) had a previous WNV infection. Of these mothers, 0.20% (3/1,472) had antibody to both DENV and WNV as evidence of infection by both viruses. The results indicated that 0.2% (3/1472) of the mothers were positive for antibody to only WNV envelope, thus suggesting an undetermined flavivirus infection. Although 6 of the 11 DENV antibody positive mothers did not have a history of travel to a DENV endemic country, the findings of this survey provided further evidence of local transmission of WNV and suggested the possibility of focal autochthonous transmission of DENV in the El Paso community., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
- Full Text
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47. Serological Evidence of West Nile Virus Infection in White-Tailed Deer in Central Texas.
- Author
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Palermo PM, Orbegozo J, Morrill JC, and Watts DM
- Subjects
- Animals, Antibodies, Viral blood, Texas epidemiology, West Nile Fever epidemiology, West Nile Fever virology, West Nile virus immunology, Deer virology, Serologic Tests veterinary, West Nile Fever veterinary
- Abstract
White-tailed deer (WTD) are abundant mammals widely distributed across the United States. As a result, WTD are considered to be excellent sentinels for detecting arboviral activity in certain geographic areas. Evidence of West Nile virus (WNV) antibody in WTD has been reported previously in several states. However, WNV infection in WTD has not been reported from Texas, where the incidence of human West Nile (WN) cases is among the highest in the United States. Therefore, the aim of this study was to determine the prevalence of WNV antibody in WTD in central Texas. Sera samples ( n = 644) were collected from deer during the fall and winter in western Travis County, Texas from 2014 to 2018 and tested for WNV immunoglobulin G (IgG) antibody by an indirect enzyme-linked immunosorbent assay (ELISA). ELISA antibody-positive samples were further tested for WNV and St. Louis encephalitis virus (SLEV) antibodies by an 80% plaque-reduction neutralization tests (PRNT
80 ). Overall, 9% ( n = 58) and 0.31% ( n = 2) of the deer samples had serological evidence of WNV and SLEV infections, respectively. WNV seroprevalence differed significantly by age ( p < 0.05), but there was no significant difference between sex. Interestingly, 3.1% ( n = 20) of the samples were positive for Flavivirus IgG antibody by ELISA, but negative for SLEV and WNV antibodies, suggesting that other Flaviviruses may be circulating among WTD in Texas. Finally, these results supported WNV infection among WTD and highlight their potential role as sentinels for the detection of WNV in Texas and warrant further studies to determine the role WTD play in the maintenance and transmission of WNV.- Published
- 2020
- Full Text
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48. Safety and immunogenicity of the Rift Valley fever arMP-12 ΔNSm21/384 candidate vaccine in pregnant ewes.
- Author
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Boumart Z, Bamouh Z, Hamdi J, Safini N, Tadlaoui KO, Bettinger G, Watts DM, and Elharrak M
- Abstract
Rift Valley fever (RVF) poses a threat to human and animal health as well as economic losses due to abortion, new-born teratogenic effect and mortality. Safe and effective vaccines are critically needed to prevent the disease in humans and livestock. The objective of this study was to assess safety and immunogenicity of the Rift Valley fever virus (RVFV) arMP-12DNSm21/384 attenuated vaccine in 32 pregnant ewes at different stages of pregnancy including 17 ewes vaccinated during the early stage (G1) of pregnancy (<35 days) and 15 ewes vaccinated during the last two stages (G2) of pregnancy (>35 days). Ewes were monitored for clinical observations, rectal temperature and abortions and lambs were monitored for general health and rectal temperature. Vaccinated ewes and lambs were periodically sampled for their neutralizing antibody response to RVFV vaccination. All ewes were positive for antibody two weeks post-vaccination and 79% of ewes were positive at delivery. None of the 32 ewes aborted during pregnancy and all ewes vaccinated during the G2 stages of pregnancy gave birth to healthy lambs. However, among the 17 ewes vaccinated during the G1 stage of pregnancy, 2 ewes gave birth to 2 lambs with fore limb malformations that died at 1-day of age. One ewe gave birth to 2 punny twins that died at 2 days of age. Another ewe, gave birth to one lamb with a deformed tail that died at 20 days of age. At post-mortem, tissues of dead lambs (spleen, lung, brain and long bone) were negative for RVFV by PCR assay. While the findings did not link the malformed lambs directly to infection by the vaccine virus, these results indicated that pregnant sheep should not be vaccinated with the RVFV arMP-12DNSm21/384 vaccine during the first month of gestation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Authors.)
- Published
- 2020
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49. Complete genomic sequences of Venezuelan equine encephalitis virus subtype IIID isolates from mosquitoes.
- Author
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Padilla SL, Prieto K, Dohm DJ, Turell MJ, Klein TA, Fernández R, Watts DM, Lowen RG, Palacios GF, Pitt ML, Wiley MR, and Nasar F
- Subjects
- Animals, Base Sequence, Encephalitis Virus, Venezuelan Equine classification, Encephalitis Virus, Venezuelan Equine genetics, Encephalomyelitis, Venezuelan Equine transmission, Genomics, Horses, Peru, Phylogeny, Culex virology, Encephalitis Virus, Venezuelan Equine isolation & purification, Encephalomyelitis, Venezuelan Equine virology, Genome, Viral, Mosquito Vectors virology
- Abstract
Venezuelan equine encephalitis virus (VEEV) is an important pathogen of medical and veterinary importance in the Americas. In this report, we present the complete genome sequences of five VEEV isolates obtained from pools of Culex (Melanoconion) gnomatos (4) or Culex (Melanoconion) pedroi (1) from Iquitos, Peru. Genetic and phylogenetic analyses showed that all five isolates grouped within the VEEV complex sister to VEEV IIIC and are members of subtype IIID. This is the first report of full-length genomic sequences of VEEV IIID.
- Published
- 2020
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50. Lipid-Mediated Insertion of Toll-Like Receptor (TLR) Ligands for Facile Immune Cell Engineering.
- Author
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Zhang MH, Slaby EM, Stephanie G, Yu C, Watts DM, Liu H, and Szeto GL
- Subjects
- Animals, Drug Delivery Systems methods, Ligands, Lymphocyte Activation, Mice, Mice, Inbred C57BL, Adjuvants, Immunologic administration & dosage, Cell Engineering methods, Lipids, Lymphocytes, Toll-Like Receptors immunology
- Abstract
Cell-based immunotherapies have tremendous potential to treat many diseases, such as activating immunity in cancer or suppressing it in autoimmune diseases. Most cell-based cancer immunotherapies in the clinic provide adjuvant signals through genetic engineering to enhance T cell functions. However, genetically encoded signals have minimal control over dosing and persist for the life of a cell lineage. These properties make it difficult to balance increasing therapeutic efficacy with reducing toxicities. Here, we demonstrated the potential of phospholipid-coupled ligands as a non-genetic system for immune cell engineering. This system provides simple, controlled, non-genetic adjuvant delivery to immune cells via lipid-mediated insertion into plasma membranes. Lipid-mediated insertion (termed depoting) successfully delivered Toll-like receptor (TLR) ligands intracellularly and onto cell surfaces of diverse immune cells. These ligands depoted into immune cells in a dose-controlled fashion and did not compete during multiplex pairwise loading. Immune cell activation could be enhanced by autocrine and paracrine mechanisms depending on the biology of the TLR ligand tested. Depoted ligands functionally persisted on plasma membranes for up to 4 days in naïve and activated T cells, enhancing their activation, proliferation, and skewing cytokine secretion. Our data showed that depoted ligands provided a persistent yet non-permanent adjuvant signal to immune cells that may minimize the intensity and duration of toxicities compared to permanent genetic delivery. Altogether, these findings demonstrate potential for lipid-mediated depoting as a universal cell engineering approach with unique, complementary advantages to other cell engineering methods., (Copyright © 2020 Zhang, Slaby, Stephanie, Yu, Watts, Liu and Szeto.)
- Published
- 2020
- Full Text
- View/download PDF
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