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The present study aimed to evaluate the effectiveness of two doses of CoronaVac in preventing SARS-CoV-2 symptomatic disease with virological confirmation, as well as in the prevention of COVID-19 moderate and severe cases. A test-negative unmatched case-control design was used, in which cases were patients with suspected COVID-19 (presenting at least two of the following symptoms: fever, chills, sore throat, headache, cough, runny nose, olfactory or taste disorders) with virological confirmation, and controls were those whose SARS-CoV-2 test was negative. As for exposure, participants were classified as unvaccinated, or vaccinated with a complete schedule. Suspected COVID-19 cases were identified from March to November 2021, in two cities located in the State of São Paulo, Brazil. All participants signed the Informed Consent Form before enrollment. RT-PCR results and vaccination data were obtained from the local surveillance systems. Up to two phone calls were made to obtain information on the outcome of the cases. A total of 2981 potential participants were screened for eligibility, of which 2163 were included, being 493 cases and 1670 controls. Vaccination, age, the reported contact with a COVID-19 suspected or confirmed case in the 14 days before symptoms onset, and the educational level were the variables independently associated with the outcome. The adjusted vaccine effectiveness for symptomatic COVID-19 (AVE) was 39.0 % (95 % CI 6.0-60.0 %). The AVE in the prevention of moderate and severe disease was 91.0 % (95 % CI 76.0-97.0 %). Our results were influenced by the waning of the Gamma variant, in the second trimester of 2021, followed by the increase in vaccination coverage, and a drop in the number of cases in the second half of the year. The study demonstrated the high effectiveness of CoronaVac in preventing moderate/severe COVID-19 cases., Competing Interests: Conflicts of interest The authors declare no conflicts of interest., (Copyright © 2024 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Stillbirth is a fundamental component of childhood mortality, but its causes are still insufficiently understood. This study aims to explore stillbirth risk factors by using a multidisciplinary approach to stimulate public policies and protocols to prevent stillbirth, improve maternal care and support bereaved families. METHODS AND ANALYSIS: In this case-control study with stillbirths and live births in 14 public hospitals in São Paulo, mothers are interviewed at hospitals after delivery, and hospital records and prenatal care registries are reviewed. Maternal and umbilical cord blood samples and placentas are collected to analyse angiogenesis and infection biomarkers, and the placenta's anatomopathological exam. Air pollutant exposure is estimated through the participant's residence and work addresses. Traditional and non-invasive autopsies by image-guided histopathology are conducted in a subset of stillbirths. Subsample mothers of cases are interviewed at home 2 months after delivery on how they were dealing with grief. Information contained in the official prenatal care registries of cases and controls is being compiled. Hospital managers are interviewed about the care offered to stillbirth mothers. Data analysis will identify the main risk factors for stillbirth, investigate their interrelations, and evaluate health services care and support for bereaved families. We hope this project will contribute to the understanding of stillbirth's risk factors and related health services in Brazil, providing new knowledge about this central public health problem, contributing to the improvement of public policies and prenatal and puerperal care, helping to prevent stillbirths and improve the healthcare and support for bereaved families. ETHICS AND DISSEMINATION: This study protocol was approved by the Ethics Committee of the Municipal Health Secretary (process no 16509319.0.3012.5551) and of the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (process no 16509319.0.0000.0068). Results will be communicated to the study participants, policy-makers and the scientific community., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil., Methods: This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained., Results: The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%., Conclusions: The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy., Competing Interests: Conflict of interest. None declared.

The identification of Leishmania species that cause tegumentary leishmaniasis (TL) is important for taxonomic and prognostic purposes. Molecular analysis using different Leishmania genomic targets is the most useful method for identifying Leishmania species. Therefore, we evaluated the performance of ribosomal RNA internal transcribed spacer 1 (ITS1) and heat shock protein (hsp70) genetic markers by polymerase chain reaction (PCR), followed by restriction fragment length polymorphism analysis (RFLP) and sequencing, for identification of Leishmania species. Samples from 84 Brazilian patients were amplified. Internal transcribed spacer 1 PCR followed by RFLP (HaeIII) [ITS1-RFLP (HaeIII)] identified 46.4% (39/84) of the samples as compatible with the Viannia subgenus. Internal transcribed spacer 1 PCR followed by sequencing (ITS1-sequencing) identified Leishmania (Viannia) braziliensis in 91.7% (77/84) of the TL samples, Leishmania (Leishmania) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 2.4% (2/84), and L. (L.) infantum in 1.2% (1/84). One of the samples showed the same proportion of similarity with L. (V.) guyanensis and L. (V.) panamensis. hsp70 nested PCR followed by RFLP (HaeIII) [nested hsp70-RFLP (HaeIII)] identified 91.7% (77/84) of the samples as compatible with L. (V.) braziliensis/L. (V.) naiffi, 3.6% (3/84) with L. (L.) amazonensis, 1.2% (1/84) with L. (L.) infantum, and 3.6% (3/84) with L. (V.) guyanensis. hsp70 PCR followed by sequencing (hsp70-sequencing) identified L. (V.) braziliensis in 91.7% (77/84) of the TL samples, L. (L.) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 3.6% (3/84), and L. (L.) infantum in 1.2% (1/84). Our findings clearly showed that nested hsp70-RFLP (HaeIII) is better than ITS1-RFLP (HaeIII) and that ITS1 or hsp70 PCR followed by sequencing was adequate for identifying Leishmania species. We also found that Leishmania (Viannia) braziliensis is the most common species causing TL in Brazil. Therefore, sequencing multiple target genes such as ITS1 and hsp 70 is more accurate than RFLP for identifying Leishmania species.

Purpose: To assess the contemporary prevalence of trachoma in Brazil's non-indigenous population, surveys of those thought to be at greatest risk of disease were conducted., Methods: Rural census tracts of non-indigenous population from nine mesoregions were selected to compose the survey evaluation units (EUs) by considering previously endemic municipalities at greatest risk of trachoma. In each of the nine EUs, we conducted a population-based prevalence survey. Every resident of selected households aged ≥ 1 year was examined for trachomatous inflammation - follicular (TF) and trachomatous trichiasis (TT). Additionally, data were collected on household-level access to water, sanitation, hygiene (WASH) and education., Results: A total of 27,962 individuals were examined across nine EUs. The age-adjusted TF prevalence in 1-9-year-olds was <5% in each EU. The age- and gender-adjusted prevalence of TT unknown to the health system in ≥15-year-olds was <0.2% in eight EUs; in one EU, it was 0.22%. The median number of households surveyed per EU with access to an improved drinking water source within a 30-minute roundtrip of the house was 66%. School attendance was >99% of surveyed children., Conclusions: The prevalence of TF was well below the target for elimination as a public health problem in all EUs. Because EUs surveyed were selected to represent the highest-risk non-indigenous areas of the country, TF prevalence is unlikely to be ≥5% in non-indigenous populations elsewhere. In one EU, the prevalence of TT was above the target threshold for elimination. Further investigation and possibly improvement in TT surgical provision are required in that EU.

Objects: This study aimed to describe COVID-19 cases in healthcare workers at a large tertiary hospital, after a vaccination campaign, to understand the individual characteristics, timeliness, symptomatology, and severity of the conditions., Methods: The COVID-19 reporting files from the hospital's healthcare workers and their records in the vaccine registry were analyzed, regarding vaccination status, symptoms, sociodemographic characteristics, comorbidities, and outcomes. Vaccination descriptive analysis was carried out and the impact and effectiveness of vaccination in relation to symptomatic infection and hospitalization were estimated., Results: In a total of 696 PCR-confirmed COVID-19 patients, vaccination coverage for the 1 st and 2 nd dose was 92.8% and 85.5%. Patients with complete doses had a mean interval of 96.8 days between vaccination and the onset of symptoms. Of the 664 participants with available clinical data, 165 had at least 1 comorbidity. During the study, 12 patients were hospitalized, 58.3% with a complete vaccination schedule. Three of this group died. The effectiveness of vaccination for symptomatic cases and hospitalization was 22.1% and 69.0%, respectively. The impact of vaccination on symptomatic cases and hospitalization was 81.4% and 89.7%, respectively., Discussion: The majority of COVID-19 cases in the study were classified as mild. The impact of vaccination for confirmed cases was significant, both in reducing the incidence of symptomatic cases and hospitalizations. The presence of comorbidities in approximately ¼ of the patients increased the risk of these individuals. The mean time interval between diagnosis and the 2 nd dose of vaccine was longer in the hospitalized group, reinforcing the protective decline over longer periods., Competing Interests: Conflicts of interest The authors declare no conflict of interests. Every author had full access to all of the data, including statistical reports and tables, and they all take responsibility for the integrity of the data and the accuracy of the analysis., (Copyright © 2022 HCFMUSP. Published by Elsevier España, S.L.U. All rights reserved.)

Background: The Brazilian state of Paraná conducted a mass vaccination campaign against dengue with the tetravalent attenuated vaccine CYD-TDV. The campaign targeted thirty endemic municipalities. The objective of this study was to assess the effectiveness of CYD-TDV in preventing symptomatic virologically confirmed dengue cases according to specific age groups in five of the municipalities., Methods: A case-control study was carried out in the five most populous municipalities targeted by the vaccination, with a vaccine uptake of 25%. Symptomatic dengue cases were identified by the municipal health departments. The age groups targeted were 15-18 and 19-27 in four municipalities and 9-14 and 28-44 in one municipality. All cases were confirmed by real time reverse transcription quantitative polymerase chain reaction (RT-qPCR). For each case, two controls were selected: a neighbourhood control and a workplace or school/college control, matched by age group. A conditional logistic regression model was used to determine the odds ratio for vaccination and the vaccine effectiveness., Findings: Study participants included 618 RT-qPCR-confirmed dengue cases and 1,236 matched controls (with a non-reactive dengue IgM serologic test). Vaccine effectiveness against dengue due to any serotype was 11·1% (95% CI: -19·0%; 33·6%). Effectiveness against DENV-1 was 33·3% (95% CI: -5·0%; 57·6%) and against DENV-2 was -56·7% (95% CI: -142·2%; -5·0%). No DENV-3 was detected. The vaccine was significantly effective in the prevention of DENV-4 cases (VE = 93·3%; 95% CI: 47·7%; 99·2%)., Interpretation: CYD-TDV was effective in the prevention of symptomatic cases due to DENV-4, but not due to any serotype. The low dengue seroprevalence in the target population could possibly be related to these results., Funding: This study was supported through a grant to the Sabin Vaccine Institute from Sanofi-Pasteur. Sanofi-Pasteur had no role in the study design, protocol development, data collection, analysis, or publication of results., Competing Interests: EJA Luna and JC Moraes have received consultancy fees and travel sponsorship from Sanofi-Pasteur. D Garrett, F. Crosewski, I Riediger, F Fantinato and K Ribeiro declare no conflict of interest. The Sabin Vaccine Institute sponsored this study. The study was registered at clinicaltrials.gov before enrolment was initiated (NTC03960385)., (© 2021 The Author(s).)

Dengue fever is re-emerging worldwide, however the reasons of this new emergence are not fully understood. Our goal was to report the incidence of dengue in one of the most populous States of Brazil, and to assess the high-risk areas using a spatial and spatio-temporal annual models including geoclimatic, demographic and socioeconomic characteristics. An ecological study with both, a spatial and a temporal component was carried out in Sao Paulo State, Southeastern Brazil, between January 1st, 2007 and December 31st, 2019. Crude and Bayesian empirical rates of dengue cases following by Standardized Incidence Ratios (SIR) were calculated considering the municipalities as the analytical units and using the Integrated Nested Laplace Approximation in a Bayesian context. A total of 2,027,142 cases of dengue were reported during the studied period. The spatial model allocated the municipalities in four groups according to the SIR values: (I) SIR<0.8; (II) SIR 0.8<1.2; (III) SIR 1.2<2.0 and SIR>2.0 identified the municipalities with higher risk for dengue outbreaks. "Hot spots" are shown in the thematic maps. Significant correlations between SIR and two climate variables, two demographic variables and one socioeconomical variable were found. No significant correlations were found in the spatio-temporal model. The incidence of dengue exhibited an inconstant and unpredictable variation every year. The highest rates of dengue are concentrated in geographical clusters with lower surface pressure, rainfall and altitude, but also in municipalities with higher degree of urbanization and better socioeconomic conditions. Nevertheless, annual consolidated variations in climatic features do not influence in the epidemic yearly pattern of dengue in southeastern Brazil.

Armadillos are specialist diggers and their burrows are used to find food, seek shelter and protect their pups. These burrows can also be shared with dozens of vertebrate and invertebrate species and; consequently, their parasites including the zoonotics. The aim of this study was to diagnose the presence of zoonotic parasites in four wild-caught armadillo species from two different Brazilian ecosystems, the Cerrado (Brazilian savanna) and the Pantanal (wetland). The investigated parasites and their correspondent diseases were: Toxoplasma gondii (toxoplasmosis), Trypanosoma cruzi (Chagas disease), Leishmania spp., (leishmaniasis), Paracoccidioides brasiliensis (Paracoccidioidomicosis) and Mycobacterium leprae (Hansen's disease). Forty-three free-living armadillos from Pantanal and seven road-killed armadillos from the Cerrado were sampled. Trypanosoma cruzi DTU TcIII were isolated from 2 out of 43 (4.65%) armadillos, including one of them also infected with Trypanosoma rangeli. Antibodies anti-T. gondii were detected in 13 out of 43 (30.2%) armadillos. All seven armadillos from Cerrado tested positive for P. brasiliensis DNA, in the lungs, spleen, liver fragments. Also, by molecular analysis, all 43 individuals were negative for M. leprae and Leishmania spp. Armadillos were infected by T. cruzi, T. rangeli, P. brasiliensis and presented seric antibodies to T. gondii, highlighting the importance of those armadillos could have in the epidemiology of zoonotic parasites., (© 2020 Wiley-VCH GmbH.)

Neglected tropical diseases constitute a heterogeneous group of diseases that have as a common characteristic to affect poor and unassisted populations with little vocalization capacity and political power. As a result, they receive little attention from the pharmaceutical industry and academia. The present study aimed to summarize the state of the art regarding vaccine development for three relevant neglected tropical diseases in Brazil: Chagas disease, schistosomiasis (Schistosoma mansoni), and leishmaniasis. To this end, we conducted a narrative review of the scientific literature, including publications that allowed us to outline a current overview on the vaccine development for the three diseases. Vaccines against the three diseases are in different stages of development. Vaccine development projects against American trypanosomiasis have yet to reach the clinical evaluation phase. For schistosomiasis, we have candidates for the vaccine in the advanced phase of clinical evaluation. For leishmaniasis, there are already licensed veterinary vaccines, and product candidates for human vaccine in the intermediate stage of clinical evaluation. The reduced funding for these projects has contributed to slow product development.

In this study which is part of a research project on Chagas disease (CD) among Bolivian immigrants in Sao Paulo, we describe socioeconomic characteristics, knowledge of CD and implications for acess to health care. We applied a structured questionnaire to a sample of 472 Bolivian adults (> 18 years) living in Sao Paulo and enrolled at the Barra Funda School Health Center. Participants' median age was 28.5 years, 75.0% were from the Bolivian department of La Paz, and >90% worked in the garment industry. Respondents had lived in Sao Paulo for a median of 5.8 years. Only 169 (35.8%) were familiar with CD, while roughly half (50.4%) had lived in natural materials houses in Bolivia, 225 (47.7%) indicated familiarity with the vector, 23.9% had seen the vector in their homes in Bolivia, and 6.4% reported having been bitten by a triatomine bug. Factors associated with awareness of CD were analyzed by chi square tests, and those with p values <0.25 were included in a multivariable logistic regression model. In the multivariable logistic regression analysis, having a relative with CD (OR=4.3, 95% CI=1.5-12.0), having lived in a house with mud or wood walls (OR=0.4, 95% CI=0.2-0.8), and having heard of the triatomine bug, or vinchuca, (OR=10.0, 95% CI=5.1-19.5) were significantly associated with awareness of CD. This study shows a low familiarity with CD among Bolivian migrants living in Sao Paulo, Brazil. Raising awareness of the disease through specific communication strategies should be an essential component of public health programs to reduce the burden of CD in this and other vulnerable populations.

The present cohort study was set up with the aim of determining the incidence of dengue among children and adolescents, from 2 to 16 years of age, living in Araraquara, South-Eastern Brazil, a city classified as a mid-level endemicity location for dengue. Enrollment took place from September 2014 to March 2015. Baseline socio-demographic data were collected, and a blood sample from the participant was drawn, for dengue serology. Families were contacted weekly for fever surveillance. If the child developed fever, a nurse visited the household to collect a blood sample. PCR, NS1 and IgM were used for dengue diagnosis. Parents or legal guardians of participating children provided a written informed consent. 3,514 children and adolescents were enrolled in the cohort. Dengue baseline seroprevalence was 12.2% (95%CI: 11.1 - 13.3). The incidence density of symptomatic dengue was 8.94 per 100 person/years in the first year of follow-up, 0.58 in the second, and 0.19 in the fourth. No cases were confirmed in the third year. Incidence was associated with age, sex, baseline seroprevalence and with living in a house as opposed to an apartment. This study provides relevant information on the epidemiology of dengue in mid-level transmission settings that may be useful to policymakers in the evaluation of control strategies., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: EJA Luna has received consultancy fees and travel grants form Sanofi-Pasteur. The other authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Approximately 240 million people worldwide are infected by Schistosoma. In Brazil, one of the main intermediate hosts of this parasite is Biomphalaria glabrata snails. The early detection of larval stages in intermediate hosts is an important challenge to public health, but it also represents an opportunity as a new alternative to indicate earlier natural infections before cercariae differentiation and emergence. In this context, we demonstrated that PCR amplification of a 28S gene fragment from the parasite does demonstrate S. mansoni infection in snails 14 days post infection. This conventional polymerase chain reaction amplified clear bands and was able to detect parasitic infection in the intermediate host B. glabrata under experimental conditions. However, we reinforce that this approach requires deeper investigations and further comparisons to confirm its specificity and sensitivity in earlier time points after miracidia infection. This approach has relevant potential as an effective molecular-based strategy for the monitoring of schistosomiasis transmission.

Objective to describe occurrence of adverse events following immunization (AEFI) with Tdap vaccine during pregnancy. Methods this was a descriptive study using data from reports by participants in an effectiveness and immunogenicity study conducted in two hospitals in São Paulo, SP, Brazil, from 2015 to 2016. Results of the 201 mothers included in the study, 48 (23.9%) had at least one AEFI; 60 symptoms related to Tdap use were identified - pain (22.4%), swelling (2.5%), fever (1.5%), somnolence (1.0%), redness (0.5%), vomiting (0.5%), headache (0.5%), local reaction (0.5%), and fatigue (0.5%); no rare, very rare, or extremely rare adverse events were reported; all events were considered to be expected, as they are described in the vaccine package insert; outcome of all events was recovery without sequelae. Conclusion Tdap vaccine in the form adopted by the National Immunization Program is safe; no unexpected adverse events were identified among vaccinated pregnant women.

Introduction: Influenza is an important cause of morbimortality worldwide. Although people at the extremes of age have a greater risk of complications, influenza has been more frequently investigated in the elderly than in children, and inpatients than outpatients. Yearly vaccination with trivalent or quadrivalent vaccines is the main strategy to control influenza., Objectives: Determine the clinical and molecular characteristics of influenza A and B infections in children and adolescents with influenza-like illness (ILI)., Methods: A cohort of outpatient children and adolescents with ILI was followed for 20 months. Influenza was diagnosed with commercial multiplex PCR platforms., Results: 179 patients had 277 episodes of ILI, being 79 episodes of influenza A and 20 episodes of influenza B. Influenza A and B cases were mild and had similar presentation. Phylogenetic tree of influenza B viruses showed that 91.6% belonged to the B/Yamagata lineage, which is not included in trivalent vaccines., Conclusions: Influenza A and B are often detected in children and adolescents with ILI episodes, with similar and mild presentation in outpatients. The mismatch between the circulating influenza viruses and the trivalent vaccine offered in Brazil may have contributed to the high frequency of influenza A and B in this population., (Copyright © 2020 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Introduction: In 2014, the Brazilian Ministry of Health (MoH) recommended Tdap to pregnant women in response to a significant increase in the incidence of pertussis among infants. The present study assessed the effectiveness of maternal immunization in preventing pertussis in infants., Methods: An unmatched case-control study was undertaken in São Paulo State, Brazil from February 2015 to July 2016. Cases were infants aged <8 weeks at onset of pertussis reported to the Surveillance System and confirmed by real-time polymerase chain reaction or culture. Four to six healthy infants were selected as controls per case from birth certificates in the Information System on Live Births database. General characteristics and mother's vaccination status were compared between cases and controls. The vaccine effectiveness (VE) was calculated as 1 - odds ratio (OR). For the adjusted VE, the OR was calculated using logistic regression analysis., Results: Forty-two cases and 248 controls were enrolled in the study. Mothers of 8 cases (19.1%) and 143 controls (57.4%) were vaccinated during pregnancy, resulting in an unadjusted VE of 82.6% (95% confidence interval [CI], 60.8-92.3%). The VE was unchanged after adjusting for maternal age and monthly household income., Conclusion: Maternal pertussis vaccination during pregnancy was effective in protecting infants aged <8 weeks from pertussis., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Pertussis remains an important global public health concern, despite the presence of extensive immunization programs. Incidence and severity of pertussis are typically higher in neonates and young infants. As a strategy to protect these young infants, maternal vaccination with Tdap (tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis) has been recommended in Brazil. The objective of this study was to evaluate the effects of Tdap vaccination during pregnancy on the anti-pertussis toxin (PT) IgG response in mothers and their infants at birth., Material and Methods: Maternal and cord blood samples were collected from vaccinated (n = 243) and unvaccinated (n = 75) pregnant women, at the time of delivery, from July 2015 to August 2016 in São Paulo, Brazil. Anti-PT IgG antibodies were quantified by Enzyme-Linked Immunosorbent Assay (ELISA) and geometric mean concentrations (GMC) were calculated. Relationship between timing of vaccination and antibody concentrations were evaluated., Results: Maternal and cord blood GMCs among the vaccinated group were 5.4 and 5.6 fold higher [66.5 International Units (IU)/mL and 89.8 IU/mL] compared to the unvaccinated group (12.4 IU/mL and 16.1 IU/mL), respectively (p < 0.001). Higher anti-PT IgG GMCs were observed when vaccination occurred ≥60 days before delivery compared to <60 days, suggesting that vaccination early in the third trimester may be more effective than later in pregnancy., Conclusion: Tdap maternal vaccination results in significantly higher anti-PT IgG in newborn infants and supports the current recommendation of the Brazilian Immunization Program., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The first licensed dengue vaccine, CYD-TDV (Dengvaxia) is efficacious in seropositive individuals, but increases the risk for severe dengue in seronegative persons about two years after administration of the first dose. For countries considering the introduction of Dengvaxia, WHO recommends a pre-vaccination screening strategy whereby only persons with evidence of a past dengue infection would be vaccinated. Policy-makers need to consider the risk-benefit of vaccination strategies based on such screening tests, the optimal age to introduce the vaccine, communication and implementation strategies. To address these questions, the Global Dengue and Aedes-transmitted diseases Consortium (GDAC) organized a 3-day workshop in January 2019 with country representatives from Asia and Latin America. The meeting discussions highlighted many challenges in introducing Dengvaxia, in terms of screening test characteristics, costs of such tests combined with a 3-dose schedule, logistics, achieving high coverage rates, vaccine confidence and communication; more challenges than for any other vaccine introduction programme. A screening test would require a high specificity to minimize individual risk, and at the same time high sensitivity to maximize individual and population benefit. The underlying seroprevalence dependent positive predictive value is the best indicator for an acceptable safety profile of a pre-vaccination screening strategy. The working groups discussed many possible implementation strategies. Addressing the bottlenecks in school-based vaccine introduction for Dengvaxia will also benefit other vaccines such as HPV and booster doses for tetanus and pertussis. Levels of public trust are highly variable and context specific, and understanding of population perceptions and concerns is essential to tailor interventions, monitor and mitigate risks., (Copyright © 2019.)

Background: We aimed to estimate and compare the ability of clinical tools for dengue diagnosis in a pediatric population., Methods: We prospectively evaluated episodes of acute febrile syndrome identified during the follow-up of a population-based cohort of children and adolescents residing in a dengue endemic city. We estimated the area under the receiver operating characteristic curve (AU-ROC) for dengue diagnosis of three clinical tools: the summation of manifestations of the WHO case definition, a predefined clinical scale and a logistic regression model obtained in this study., Results: We compared 219 dengue cases (confirmed by laboratory) and 286 patients with other febrile illnesses. In a multiple model, variables independently associated with dengue included the duration of fever, sleepiness and exanthema. Rhinorrhea, cough and minimal leukocyte count were inversely associated with dengue. This model reached an accuracy of 84.2% (for a cut-off of >0.5, sensitivity: 79.5%, specificity: 87.9%, positive predictive value: 83.7%, negative predictive value: 84.6%). The AU-ROC of this model (89.8%) was significantly higher than that obtained with either the predefined scale (82.1%) or the WHO definition manifestations (77%)., Conclusion: We validated a predefined scale and identified a multiple model suitable for the clinical diagnosis of dengue in the pediatric population., (© The Author(s) 2018. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Children play an important role in maintaining the transmission of influenza. Evidence suggests that vaccination of school-age children can reduce transmission to unvaccinated household contacts. We evaluated the direct and indirect effectiveness of the 2009 inactivated seasonal influenza vaccine in vaccinated schoolchildren and their unvaccinated household contacts., Methods: This was a double-blind cluster randomized trial involving 10 schools and 1742 schoolchildren as well as 5406 household contacts. The schools were randomly assigned to receive the influenza vaccine or the control vaccine. After vaccination, the schoolchildren and household contacts were followed for 6 months to identify cases of acute respiratory infection (ARI). Reverse-transcriptase polymerase chain reaction was performed for the diagnosis of influenza., Results: A total of 632 ARI cases were detected. Of those, 103 tested positive for influenza virus (influenza virus A[H1N1]pdm09 virus in 55 and seasonal influenza viruses in 48). The effectiveness of the vaccine in protecting against seasonal influenza virus infection was 65·0% for the household contacts (95% CI, 19·6-84·3) and 65·0% for the schoolchildren (95% CI, 20·9-84·5)., Conclusion: Vaccination of schoolchildren significantly protected them and their household contacts against seasonal influenza., (© 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)

To increase the timeliness of detection of human cases of the new variant of Creutzfeldt-Jakob disease (vCJD) and to reduce the risk of transmission, the Brazilian Ministry of Health has established and standardized rules and control measures. These include the definition of criteria for suspect cases, reporting, monitoring, and control measures for illness prevention and transmission. Guidelines to be used by the team of health care staff were published and distributed to health workers. A detailed proposal for a simplified system of surveillance for prion diseases was developed and mandatory reporting introduced. Additional effort is necessary to increase vCJD case detection, thus making it necessary to establish a partnership with health care services for best identification of suspected cases and dissemination of information to all involved in the service dealing with vCJD investigation.