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Background: Healthcare workers' hands are the foremost means of pathogen transmission in healthcare, but detailed hand trajectories have been insufficiently researched so far. We developed and applied a new method to systematically document hand-to-surface exposures (HSE) to delineate true hand transmission pathways in real-life healthcare settings. Methods: A head-mounted camera and commercial coding software were used to capture ten active care episodes by eight nurses and two physicians and code HSE type and duration using a hierarchical coding scheme. We identified HSE sequences of particular relevance to infectious risks for patients based on the WHO 'Five Moments for Hand Hygiene'. The study took place in a trauma intensive care unit in a 900-bed university hospital in Switzerland. Results: Overall, the ten videos totaled 296.5 min and featured eight nurses and two physicians. A total of 4222 HSE were identified (1 HSE every 4.2 s), which concerned bare (79%) and gloved (21%) hands. The HSE inside the patient zone (n = 1775; 42%) included mobile objects (33%), immobile surfaces (5%), and patient intact skin (4%), while HSE outside the patient zone (n = 1953; 46%) included HCW's own body (10%), mobile objects (28%), and immobile surfaces (8%). A further 494 (12%) events involved patient critical sites. Sequential analysis revealed 291 HSE transitions from outside to inside patient zone, i.e. "colonization events", and 217 from any surface to critical sites, i.e. "infection events". Hand hygiene occurred 97 times, 14 (5% adherence) times at colonization events and three (1% adherence) times at infection events. On average, hand rubbing lasted 13 ± 9 s. Conclusions: The abundance of HSE underscores the central role of hands in the spread of potential pathogens while hand hygiene occurred rarely at potential colonization and infection events. Our approach produced a valid video and coding instrument for in-depth analysis of hand trajectories during active patient care that may help to design more efficient prevention schemes. [ABSTRACT FROM AUTHOR]

The main objective of this study was to characterize spatial patterns of white-tailed deer ( Odocoileus virginianus) movement related to bovine tuberculosis ( bTB) transmission risk to cattle in north-western Minnesota. Twenty-one adult deer (16 females and 5 males) were captured during winter (January-March) 2011 in areas adjacent to where an outbreak (2005-2009) of bTB occurred in deer and cattle. Deer were fitted with GPS collars programmed to collect deer location information every 90 min over a 15-month period. The exact locations of cattle, cattle feeding areas, and stored forage that were available to collared deer were assessed seasonally. In total, 47% ( n = 9) of collared deer survived to the end of the study. Causes of mortality included wolves ( n = 6), hunters ( n = 1) and unknown ( n = 2); additionally, 2 deer were censored due to collar malfunctions. Our results indicated that 5 deer (25%) had home ranges that included 6 cattle farms (20%). Most (77%) of the deer visits occurred in areas where cattle were present, with most visits (60%) from 00:00 to 06:00. March to May revealed the most farm visitations by deer (37%). This study provided baseline information regarding cattle-deer interactions critical to transmission of bTB in this region and suggested that risk mitigation practices should be implemented to separate wildlife and domestic livestock when feasible. [ABSTRACT FROM AUTHOR]

Phlebotomine sandflies are natural vectors of Leishmania spp. and their expansion throughout has been evidenced in the last few years due to the global warming and changes in human behavior, worsening leishmaniasis problem. However, phlebotomine sandflies have been captured in small numbers on the Canary Islands, particularly on the island of Lanzarote, where only one limited survey was carried out almost thirty years ago. The proximity of this island to Morocco, in addition to the high number of tourists, sometimes accompanied by their dogs, from leishmaniasis endemic regions, highlights the importance of studying the sandfly fauna on this island in order to determine the transmission risk of leishmaniasis Thirty-eight sampling sites spread across the island were studied, and ecological features were gathered to identify the ecological traits associated to the presence of sandflies. Only 85 sandfly specimens were captured (1.18/m 2 ) with the following species distribution: Sergentomyia minuta (0.15 specimens/m 2 ), which was reported for the first time on this island, and S. fallax (1.03/m 2 ). Sandfly captured were achieved in only 7 out of 38 stations. No specimen of the Phlebotomus genus was captured and given that none of the species captured has been demonstrated vectors of human pathogenic Leishmania and considering that they were captured in low frequency and density, it can be concluded that the current leishmaniasis transmission risk is null. [ABSTRACT FROM AUTHOR]

We survey 62 users of a university asymptomatic SARS-CoV-2 testing service on details of their activities, protective behaviours and contacts in the 7 days prior to receiving a positive or negative SARS-CoV-2 PCR test result in the period October 2020–March 2021. The resulting data set is novel in capturing very detailed social contact history linked to asymptomatic disease status during a period of significant restriction on social activities. We use this data to explore 3 questions: (i) Did participation in university activities enhance infection risk? (ii) How do contact definitions rank in their ability to explain test outcome during periods of social restrictions? (iii) Do patterns in the protective behaviours help explain discrepancies between the explanatory performance of different contact measures? We classify activities into settings and use Bayesian logistic regression to model test outcome, computing posterior model probabilities to compare the performance of models adopting different contact definitions. Associations between protective behaviours, participant characteristics and setting are explored at the level of individual activities using multiple correspondence analysis (MCA). We find that participation in air travel or non-university work activities was associated with a positive asymptomatic SARS-CoV-2 PCR test, in contrast to participation in research and teaching settings. Intriguingly, logistic regression models with binary measures of contact in a setting performed better than more traditional contact numbers or person contact hours (PCH). The MCA indicates that patterns of protective behaviours vary between setting, in a manner which may help explain the preference for any participation as a contact measure. We conclude that linked PCR testing and social contact data can in principle be used to test the utility of contact definitions, and the investigation of contact definitions in larger linked studies is warranted to ensure contact data can capture environmental and social factors influencing transmission risk. • We regress SARS-CoV-2 test outcome on setting-specific contact for university members. • Participation in university activities was not associated with SARS-CoV-2 infection. • A binary definition of contact provided a better model than total contacts. • Different patterns of protective behaviour between settings may explain this result. • Further exploration of protective behaviours in contact diary studies is warranted. [ABSTRACT FROM AUTHOR]

What Is Already Known About This Topic?: Although ticks and tick-borne diseases are prevalent throughout China, there remains a knowledge gap regarding their biology and potential risk of distribution to human and animal populations on Chongming Island. The island, being China's third largest and a crucial component in the ecological preservation of the Yangtze Delta region, has yet to be comprehensively studied in this context., What Is Added by This Report?: In this study, employing molecular methodologies, a significant prevalence of Haemaphysalis ( H .) longicornis and H. flava ticks - widely recognized for their high pathogenicity - is reported from Chongming Island. Additionally, the identification of two previously unreported species on the island, namely, H. doenitzi and H. japonica , expands our understanding of both the range and evolution of tick species., What Are the Implications for Public Health Practice?: The populations of humans and animals in nearly all 18 towns on Chongming Island are potentially at risk for transmission of tick-borne infectious agents. As a result, there is a pressing necessity for public health alerts, proactive tick surveillance, and effective screening of suspected clinical cases of tick-borne diseases within the Chongming population., Competing Interests: Xiao-nong Zhou is an editorial board member of the journal China CDC Weekly. He was not involved in the peer-review or handling of the manuscript. The authors have no other competing interests to disclose., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2023.)

Understanding infection transmission between individuals, as well as evaluating the efficacy of protective measures, are key issues in pandemics driven by human respiratory particles. The key is a quantitative understanding of the size and concentration of particles exhaled and their variability across the size range for a representative population of all ages, genders, and different activities. Here we present data from 132 healthy volunteers aged 5 to 80 years, measured over the entire particle size range for each individual. Conventional particle spectrometry was combined with in-line holography under well-controlled conditions for common activities such as breathing, speaking, singing, and shouting. We find age to be the most important parameter for the concentration of small exhale particles <5 µm (PM5), which doubles over a 7-year period in adolescents and over a 30-year period in adults. Gender, body mass index, smoking or exercise habits have no discernible effect. We provide evidence that particles with a diameter of <5 µm originate from the lower respiratory tract, 5–15 µm from the larynx/pharynx, and >15 µm from the oral cavity. PM5 concentration can vary by one order of magnitude within a person, while inter-person variability can span two orders of magnitude, largely explained by difference in age. We found no discernible inter-person variability for particles larger than 5 µm. Our results show that cumulative volume of PM5 is 2–8 times higher in adults than in children. In contrast, number and volume concentration of larger particles, which are produced predominantly in the upper respiratory tract, is largely independent of age. Finally, we examined different types of airborne-transmissible respiratory diseases and provided insights into possible modes of infection transmission with and without several types/fits of face masks. • Measurement of particles in the air exhaled by 132 persons aged 5–80 years. • Aerosol spectrometry and in-line holography used to measure nm to mm range. • Breathing produces mainly <5 μ m, while vocalizations have a second peak at ∼ 38 μ m. • Biological age is important for particles <5 μ m, gender and BMI have no impact. • <5 μ m originate from lungs, 5–15 μ m from larynx/throat, >15 μ m from oral cavity. [ABSTRACT FROM AUTHOR]

Activities such as singing or playing a wind instrument release respiratory particles into the air that may contain pathogens and thus pose a risk for infection transmission. Here we report measurements of the size distribution, number, and volume concentration of exhaled particles from 31 healthy musicians playing 20 types of wind instruments using aerosol size spectrometry complemented with in-line holography in a strictly controlled cleanroom environment. We find that playing wind instruments carries a lower risk of airborne disease transmission than speaking or singing. We attribute this to the fact that the resonators of wind instruments act as filters for particles > 10 µm in diameter, which were found in high abundance right after a brass mouthpiece but very rarely at the instrument bell end. We have also measured the size-dependent filtering properties of different types of filters that can be used as instrument masks. Based on these measurements, we calculated the risk of airborne transmission of SARS-CoV-2 in different near- and far-field scenarios with and without masking and/or distancing. We conclude that in all cases where there is a possibility that the musician is infectious, the only safe measure to prevent airborne transmission of the disease is the use of well-fitting and well-filtering masks for the instrument and the susceptible person. • Particle emission measured on 20 wind instrument types under controlled conditions. • Emitted particle volume concentration mostly between normal breathing and speaking. • Upper bound of risk for SARS CoV-2 infection transmission for near- and far-field. • Universal masking found to yield the best protection against infection transmission. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives: Schistosomiasis is a zoonotic infectious disease that seriously harms people's physical and mental health. As early as 1985, the WHO suggested that health education and health promotion should be the focus of schistosomiasis prevention work. This study aimed to explore the effect of health education on controlling the risk of schistosomiasis transmission after schistosomiasis blocking and to provide a scientific basis for the further improvement of intervention strategies after schistosomiasis interruption in China and other endemic countries., Methods: In Jiangling County, Hubei Province, China, one severe, one moderate, and one mildly endemic village were selected as the intervention group; two severe, two moderate, and two mildly endemic villages were selected as the control group. In towns with different epidemic types, a primary school was randomly selected for intervention. In September 2020, a baseline survey was carried out through a questionnaire survey to understand the knowledge, attitudes, and practices (KAP) of adults and students concerning schistosomiasis control. Next, two rounds of health education interventions for schistosomiasis control were carried out. The evaluation survey was conducted in September 2021 and the follow-up survey conducted in September 2022., Results: Compared with the baseline survey, the qualified rate of the KAP on schistosomiasis prevention of the control group in the follow-up survey increased from 79.1% (584/738) to 81.0% (493/609) ( p > 0.05); in the intervention group, the qualified rate of the KAP on schistosomiasis control increased from 74.9% (286/382) to 88.1% (260/295) ( p < 0.001). In the baseline survey, the qualified rate of the KAP of the intervention group was lower than that of the control group, and in the follow-up survey, the qualified rate of the KAP of the intervention group was 7.2% higher than that of the control group ( p < 0.05). Compared with the baseline survey, the accuracy rates of the KAP of the intervention group's adults were higher than those of the control group, with statistical significance ( p < 0.001). Compared with the baseline survey, the qualified rate of the students' KAP in the follow-up survey increased from 83.8% (253/302) to 97.8% (304/311) ( p < 0.001). In the follow-up survey, the accuracy rate of the knowledge, attitudes, and practices of the students was significantly different from the baseline accuracy ( p < 0.001)., Conclusion: a health education-led risk control model of schistosomiasis can significantly improve schistosomiasis control knowledge among adults and students, establishing correct attitudes and leading to the development of correct hygiene habits.

Aedes aegypti (AE) and Aedes albopictus (AA) are the two major dengue vectors in the world. To control dengue, monitoring vectors is essential. The abundance and distribution of mosquitoes are usually considered as a proxy for dengue outbreaks. Most of the researches catch the abundance and distribution of vectors by using traps, but this kind of information only can reflect partial relationship between the mosquitoes and dengue since human factors were not taken into account. To have a better proxy for dengue risk, this research evaluated the spatiotemporal distribution of dengue vectors by a human population-stratified ovitrap survey. We demonstrated the potential intensity of dengue transmission spatio-temporally in the high epidemic areas. We analyzed the temporal patterns of vector abundances, compared the levels of vector aggregation indoors with outdoors, and assess the vector concentration tendency around residential centers and administration edges form June 2010 to June 2011. We found significantly more AA outdoors than indoors, and no matter outdoor or indoor settings were, the abundances of AA were descending from the pre-epidemic period to post-epidemic period. AE also had the descending pattern, but there were no significant differences detected between outdoor and indoor settings. AA hotspots appeared almost the same locations from the pre-epidemic period to post-epidemic period, but no obvious repetitive AE hotspots were shown. We also found that AA tended to aggregate around the residential centers while AE likely clustered around the district boundaries. Our study concluded these spatio-temporal characteristics of AE and AA addressed from a population adjusted ovitrap method implied the risks of dengue in different times and locations. To more efficiently control dengue, except for routine unspecific control interventions, the authorities should realize different environmental management strategies were needed for AE and AA. [ABSTRACT FROM AUTHOR]

Background: The EUFRAT (European Up-Front Risk Assessment Tool) was developed as an online risk assessment tool ( http://eufrattool.ecdc.europa.eu ) to help decision-makers assess the transmission risk of emerging infectious diseases (EID) through blood transfusion. The aim of this study is to extend the methodology developed in the EUFRAT project to quantify the transfusion transmission (TT) risk from travelling donors.Methods: A generic model for estimating the TT risk from a group of travelling donors that visited an EID risk area was developed. In addition, the new model distinguishes projected future transmissions from those that have already occurred. As an illustration the model was applied to the outbreaks of chikungunya in Italy in 2007 and Q fever in the Netherlands in 2007-2009.Results: Formulas for calculating the travelling donors' TT risk were derived. For the chikungunya outbreak in Italy an early intervention (at the end of week 7 after the start of the outbreak, so after only 19% of all cases) would have been required to prevent only 41% of all expected transmissions at that time. For Q fever, in which the transmission of chronic Q fever is considered, even at the end of the third annual outbreak's peak 47% of all (chronic) Q fever transmissions could still be prevented.Conclusions: The updated model allows estimation of the infection transmission risk from travelling donors. In combination with the distinction between past and future transmissions, these estimates provide valuable information to support decisions concerning communication with the public and/or the implementation of safety interventions. [ABSTRACT FROM AUTHOR]

We assessed in a case-control study the test-validity of Aedes larval indices for the 2000 Havana outbreak. "Cases" were blocks where a dengue fever patient lived during the outbreak. "Controls" were randomly sampled blocks. Before, during, and after the epidemic, we calculated Breteau index (BI) and house index at the area, neighborhood, and block level. We constructed receiver operating characteristic (ROC) curves to determine their performance as predictors of dengue transmission. We observed a pronounced effect of the level of measurement. The BImax (maximum block BI in a radius of 100 m) at 2-month intervals had an area under the ROC curve of 71%. At a cutoff of 4.0, it significantly (odds ratio 6.00, p

The coronavirus disease 2019 (COVID-19) pandemic has changed the practice of gastroenterology and how we perform endoscopy. As with any new or emerging pathogen, early in the pandemic, there was limited evidence and understanding of disease transmission, limited testing capability, and resource constraints, especially availability of personal protective equipment (PPE). As the COVID-19 pandemic progressed, enhanced protocols with particular emphasis on assessing the risk status of patients and proper use of PPE have been incorporated into routine patient care. The COVID-19 pandemic has taught us important lessons for the future of gastroenterology and endoscopy., (Published by Elsevier Inc.)

Animal movements among habitat patches or populations are important for maintaining long-term genetic and demographic viability, but connectivity may also facilitate disease spread and persistence. Understanding factors that influence animal movements is critical to understanding potential transmission risk and persistence of communicable disease in spatially structured systems. We evaluated effects of sex, age and Mycoplasma ovipneumoniae infection status at capture on intermountain movements and seasonal movement rates observed in desert bighorn sheep ( Ovis canadensis nelsoni ) using global positioning system collar data from 135 individuals (27 males, 108 females) in 14 populations between 2013 and 2018, following a pneumonia outbreak linked to the pathogen M. ovipneumoniae in the Mojave Desert, California, USA. Based on logistic regression analysis, intermountain movements were influenced by sex, age and most notably, infection status at capture: males, older animals and uninfected individuals were most likely to make such movements. Based on multiple linear regression analysis, females that tested positive for M. ovipneumoniae at capture also had lower mean daily movement rates that were further influenced by season. Our study provides empirical evidence of a pathogenic infection decreasing an individual's future mobility, presumably limiting that pathogen's ability to spread, and ultimately influencing transmission risk within a spatially structured system., (© 2023 The Authors.)

Background Depot-medroxyprogesterone acetate ( DMPA) has been associated in some studies with increased HIV susceptibility in women. We used a pigtail macaque model to document the effects of repeated DMPA treatments and their potential contribution to increased SHIV susceptibility. Methods Nine pigtails were administered 2.5, 1.5, or 0.5 mg/kg DMPA in study weeks one and four. Menstrual cycling, vaginal epithelial thickness, and other SHIV susceptibility factors were monitored for a mean of 24 study weeks. Results All DMPA treatments suppressed menstrual cycling and increased vaginal pH. The vaginal epithelium thinned naturally during baseline menstrual cycles (from mean of 351 to 161 μm in late-luteal phase). Following DMPA, the non-nucleated layer was temporarily absent. Two weeks post-second DMPA injection, mean epithelial thickness was 53, 45, and 167 μm for the descending doses, respectively. Conclusions All animals showed temporal vaginal epithelial thinning with loss of the non-nucleated layer, and vaginal pH changes post- DMPA injections. [ABSTRACT FROM AUTHOR]

The transmission risk of foot-and-mouth disease (FMD) in Japan was evaluated using a mathematical FMD transmission model. The distance-based transmission rate between farms, which was parameterized using the FMD epidemic data in 2010 in Japan, was used to calculate the local-level reproduction numbers--expected numbers of secondary infections caused by one infected farm--for all cattle and pig farms in the country, which were then visualized as a risk map. The risk map demonstrated the spatial heterogeneity of transmission risk in the country and identified risk areas with higher possibility of disease spread. This result suggests that, particularly in high-risk areas, it is important to prepare for the smooth and efficient implementation of control measures against FMD outbreaks. [ABSTRACT FROM AUTHOR]

Background: Adherence problems, interactions and higher rate of risk activities have been observed in HIV individuals using recreational drugs. Our aim was to describe recreational drug use in both HIV individuals and general population in Europe, and to assess at what extent HIV guidelines address this issue. Methods: Data on recreational drug use across Europe were obtained from the European Monitoring Centre for Drugs and Drug Addiction for the general population, and through Pubmed search. for HIV patients. We assessed the incorporation of recreational drug issues in HIV treatment guidelines for the following topics: (a) recreational drugs; (b) adherence to antiretrovirals; (c) interactions; (d) transmission risk. Guidelines included: World Health Organization; European Aids Clinical Society; U.S. Department of Health and Human Services; International Antiviral Society-USA; and seven European national guidelines. Results: 29 countries reported recreational drug use in general population. The highest prevalences were observed for Cannabis (i.e., 8-10% in Spain, France, and Czech Republic) followed by cocaine, amphetamines and ecstasy. The 13 studies selected in the systematic review showed a great variability in recreational drug use on the HIV population. Apart from classical recreational drugs, we found a relevant use of new drugs including sexual experience enhancers. Polydrug consumption was about 50% in some studies. Most guidelines included general information about recreational drugs, showing great variability on the inclusion of the evaluated topics. We found more specific, evidence-based recommendations on interactions, followed by medication adherence and transmission risk. Conclusions: Available data on the people living with HIV suggest a higher use of recreational drugs than in the general population, which is already relevant. However, recreational drug issues should be included or addressed more thoroughly in most guidelines. [ABSTRACT FROM AUTHOR]

Background Injectable hormonal contraception may increase women's risk of HIV acquisition and can affect biological risk factors in animal models of HIV. We established, for the first time, a model to investigate whether combined oral contraceptives ( COC) alter SHIV susceptibility in macaques. Methods Seven pigtail macaques were administered a monophasic levonorgestrel ( LNG)/ethinyl estradiol ( EE) COC at 33% or 66% of the human dose for 60 days. Menstrual cycling, vaginal epithelial thickness, and other SHIV susceptibility factors were monitored for a mean of 18 weeks. Results Mean vaginal epithelial thicknesses were 290.8 μm at baseline and 186.2 μm during COC ( P = 0.0141, Mann- Whitney U-test). Vaginal p H decreased from 8.5 during treatment to 6.5 post-treatment (0.0176 two-tailed t-test). Measured microflora was unchanged. Conclusions COC caused thinning of the vaginal epithelium and vaginal p H changes, which may increase SHIV susceptibility. 0.033 mg LNG + .0066 mg EE appeared effective in suppressing ovulation. [ABSTRACT FROM AUTHOR]

The objective of this cohort study was to evaluate whether rearing dairy heifers at different premises than the dairy of origin (off-site) reduced the risk of Mycobacterium avium ssp. paratuberculosis (MAP) infection more effectively than rearing on the dairy of origin (on-site). From 2003 to 2005, 3 cohorts of Jersey heifers were born on a single California dairy, with heifers in the first cohort raised on-site until first calving (n = 797); heifers in the second cohort raised on-site until approximately 5 mo of age and off-site until about 1 to 2 mo precalving (n = 791); and heifers in the third cohort raised off-site from d 1 until about 1 to 2 mo before first calving (n = 797). Cohorts were sequentially enrolled, and heifers were followed until death, culling, or up to 6 yr of age. Heifers were tested annually for MAP infection by serum ELISA and bacterial culture of feces, from lactation 1 until they were 6 yr old, and all mortality and culling events were recorded. Compared with cohort 1, cohort 3 had lower hazards of seroconverting and shedding of MAP in feces, approximately 70 and 38%, respectively. Cohort 2 was not significantly different from cohort 1 for the same outcomes. Mortality hazards were only significantly different between cohorts before first calving, with calves raised completely off-site at lower risk than the remaining 2 cohorts. Additionally, the hazards for culling in cohorts 2 and 3 were only significantly different from cohort 1 after the first calving. To our knowledge, the current study is the first cohort study to evaluate the association between off-site heifer rearing and risk of MAP infection, mortality, and culling. Rearing heifer calves off-site, away from infected adult dairy cows, may have allowed for reduced exposure to MAP in the environment of the calves and, hence, served as a control strategy for Johne's disease. [ABSTRACT FROM AUTHOR]

The number of occupants in a space influences the risk of far-field airborne transmission of SARS-CoV-2 because the likelihood of having infectious and susceptible people both correlate with the number of occupants. This paper explores the relationship between occupancy and the probability of infection, and how this affects an individual person and a population of people. Mass-balance and dose–response models determine far-field transmission risks for an individual person and a population of people after sub-dividing a large reference space into 10 identical comparator spaces. For a single infected person, the dose received by an individual person in the comparator space is 10 times higher because the equivalent ventilation rate per infected person is lower when the per capita ventilation rate is preserved. However, accounting for population dispersion, such as the community prevalence of the virus, the probability of an infected person being present and uncertainty in their viral load, shows the transmission probability increases with occupancy and the reference space has a higher transmission risk. Also, far-field transmission is likely to be a rare event that requires a high emission rate, and there are a set of Goldilocks conditions that are just right when equivalent ventilation is effective at mitigating against transmission. These conditions depend on the viral load, because when they are very high or low, equivalent ventilation has little effect on transmission risk. Nevertheless, resilient buildings should deliver the equivalent ventilation rate required by standards as minimum. • Accounts for population dispersion when considering the risks of far-field exposure to a virus. • Far-field transmission is likely to be a rare event that requires a high emission rate. • Ventilation cannot is not an effective mitigation method when viral load is very high or low. • Larger spaces can pose a greater transmission risk than smaller spaces for a population of people. [ABSTRACT FROM AUTHOR]

The risk of transmission of classical scrapie via the transfer of in vivo derived embryo in ovines was assessed, taking into account the scientific information made available since the last EFSA opinion on this topic (2010) (see http://www.efsa.europa.eu/en/efsajournal/pub/1429.htm). The potential impact of PrP genotype of the embryo and/or of the ram and donor ewe on this risk was also assessed. The new data made available over the last three years further reinforce the view that classical scrapie could be vertically transmitted in sheep. Since the possibility of such vertical transmission was already considered in the previous opinion, its conclusions and recommendations relating to the risk of classical scrapie transmission via embryo transfer remain valid. In ovines, the susceptibility to classical scrapie infection in sheep is strongly influenced by certain polymorphisms of the PrP gene. Under natural exposure conditions, animals that are heterozygous or homozygous A136R154R171 display respectively a low or negligible risk of being infected. The genetic control of the susceptibility to classical scrapie is also likely to impact on the risk of transmitting the disease via embryo transfer. Irrespective of the embryo’s genotype, embryos derived from rams and dams carrying at least one ARR allele would significantly decrease this risk (compared to an embryo from parents of unknown genotypes). The use of homozygous ARR embryos would provide the highest level of safety regarding the risk of transmitting classical scrapie through embryo transfer (in vivo derived embryos). The use of heterozygous ARR embryos would ensure a higher level of safety compared to Q171/Q171 embryos. Finally, it was concluded that, providing the OIE recommendations and procedures relating to embryo transfer are adhered to, the risk of transmitting classical scrapie due to the transfer of homozygous or heterozygous ovine ARR embryos can be considered negligible.

The virological safety of medicinal leeches has to be ensured prior to their use on patients. While leeches can be kept and bred under standardized conditions, feeding them horse blood adds a non-standardized component, which poses some risk of infection of the treated patients. Here, we investigated the speed at which blood-borne viruses are degraded by the microbial flora in the leech intestine, in order to define the safety of the product and the length of the necessary quarantine period prior to its administration to patients. Feeding blood was spiked with bovine viral diarrhea virus (BVDV), reovirus, and murine parvovirus (10 ID ml). The virus titer in the intestinal contents of the leeches was determined using permissive cell cultures and compared to that of the original virus titer at the following time points: immediately after feeding; after 3, 14, and 30 days; and monthly thereafter until the 7th month. The BVDV titer was below the detection limit of 10 TCID ml after 3 months, while reovirus and murine parvovirus titers were undetectable after 4 months. No positive virus findings were obtained at later time points. Thus, when fed the blood of vertebrates, the finished product 'Medicinal leech, Hirudo verbana' can be considered virologically safe if the animals are maintained at 20 °C, which corresponds to their natural habitat conditions and ensures a high metabolic rate. Therefore, after the last feeding, a quarantine period of 4-6 months and appropriate care at room temperature, which supports microbial degradation and digestive processes, are recommended. [ABSTRACT FROM AUTHOR]

Background Long-acting, hormonal contraception may increase HIV risk. Copper intrauterine devices ( IUDs) could serve as non-hormonal alternatives. We pilot a pigtail macaque model for evaluating HIV susceptibility factors during copper IUD use. Methods Frameless and flexible GyneFix® copper IUDs were surgically implanted into three SHIVSF162p3-positive macaques via hysterotomy and monitored for up to 4 months. Four macaques served as non- IUD controls. Results All animals retained the devices without complications. No consistent change in vaginal viral RNA or inflammatory cytokines was seen. Two animals had altered menstrual cycles and experienced marked thinning of vaginal epithelium after IUD insertion. Histological examination of uterine tissue at necropsy revealed endometrial ulceration and lymphocytic inflammation with glandular loss at sites of direct IUD contact. Conclusions Although the need for insertion surgery could limit its usefulness, this model will allow studies on copper IUDs and SHIV shedding, disease progression, and HIV susceptibility factors. [ABSTRACT FROM AUTHOR]

This case comment critiques the Supreme Court of Canada’s decision in R v. Mabior. In Mabior, Chief Justice McLachlin affirmed the criminalization of human immunodeficiency virus (HIV) non-disclosure to sexual partners, and sought to clarify exactly when criminal sanctions apply. Citing expert evidence, McLachlin CJC held that criminal liability is appropriate for HIV non-disclosure when there is a ‘realistic possibility of transmission’ and that only condom use combined with antiretroviral therapy reduces this risk enough to preclude liability. Using the same expert evidence, I calculate the transmission rates underlying this argument and show that McLachlin CJC’s use of statistics results in logical contradictions and uncertain liability. I argue that her statistical approach is unworkable and I propose an alternative non-disclosure regime. [ABSTRACT FROM PUBLISHER]

Background Data on knowledge, attitudes, behaviour and practices (KABP) of persons with recent HIV infection compared to controls with negative HIV test result provide information on current risk patterns and can help to re-focus HIV prevention strategies. Methods From March 2008 through May 2010, persons newly diagnosed with HIV (cases) and HIVnegative controls were recruited by physicians in Germany. To distinguish recent (<5 months) from longstanding (>5 months) infection, dried blood spots from people newly diagnosed with HIV were tested with the BED IgG-capture ELISA. Cases and controls completed a KABP-questionnaire. We compared cases with recent infection and controls among men having sex with men (MSM) regarding reported risk behaviour in the previous 6 months. To detect differences, unadjusted Odds Ratios (OR) were calculated and multivariate analysis was performed. Results Cases and controls did not differ in terms of knowledge on transmission risks, HIV testing frequency, partnership status, or regarding the frequency of any unprotected sex with partners known to be HIV-positive or assumed to be HIV-negative. Cases more often reported a shorter duration of partnership (<6 months) with a primary partner than controls (OR = 3.9;p = 0.003) and indicated lower rates of condom use outside of primary relationships, with acquaintances (OR = 2.5;p = 0.01), and with persons met online (OR = 4.5;p = 0.04). Unprotected sex with persons of unknown HIV-serostatus was more often indicated by cases than controls (OR = 3.0;p = 0.003). Having a conversation about HIV serostatus before having sex was associated with a lower risk of infection (OR = 0.2;p = 0.01). In multivariate analysis "being always safe" (always using a condom when having sex in different situations outside of a relationship) and talking about serostatus before sex (OR = 0.23;p = 0.004;OR = 0.14;p = 0.014) were negatively associated with HIV- infection. Conclusions There were no significant differences regarding knowledge about HIV-transmission risks among cases and controls. Differences in risk behaviour were observed regarding unprotected sex with partners of unknown HIV-serostatus and duration of primary partnership at the time of diagnosis, suggesting some HIV-transmissions occurring in newly formed partnerships. The practice of discussing serostatus with prospective sex partners before engaging in sex seems to be protective for HIV-transmission. [ABSTRACT FROM AUTHOR]

Zoonotic filarioses caused by Dirofilaria immitis and Dirofilaria repens are transmitted by culicid mosquitoes. Therefore Dirofilaria transmission depends on climatic factors like temperature and humidity. In spite of the dry climate of most of the Spanish territory, there are extensive irrigated crops areas providing moist habitats favourable for mosquito breeding. A GIS model to predict the risk of Dirofilaria transmission in Spain, based on temperatures and rainfall data as well as in the distribution of irrigated crops areas, is constructed. The model predicts that potential risk of Dirofilaria transmission exists in all the Spanish territory. Highest transmission risk exists in several areas of Andalucía, Extremadura, Castilla-La Mancha, Murcia, Valencia, Aragón and Cataluña, where moderate/high temperatures coincide with extensive irrigated crops. High risk in Balearic Islands and in some points of Canary Islands, is also predicted. The lowest risk is predicted in Northern cold and scarcely or non-irrigated dry Southeastern areas. The existence of irrigations locally increases transmission risk in low rainfall areas of the Spanish territory. The model can contribute to implement rational preventive therapy guidelines in accordance with the transmission characteristics of each local area. Moreover, the use of humidity-related factors could be of interest in future predictions to be performed in countries with similar environmental characteristics. [ABSTRACT FROM AUTHOR]

Background: In-flight transmission risk of Mycobacterium tuberculosis is not well defined, although studies suggest it is low. The impact of flight-related tuberculosis (TB) contact investigations (TBCIs) on TB prevention and control is not well established, and they compete for resources with activities with established benefits. We sought to determine the risks and costebenefits of using more restrictive criteria in comparison to the Centers for Disease Control and Prevention (CDC) 2008 protocol for TBCIs. Methods: The risk-benefits of a modified CDC protocol were analyzed in comparison to the 2008 CDC protocol using data from flight-related TBCIs conducted in the United States from 2007 through 2009. We predicted the numbers and characteristics of case-travelers that would be identified using each protocol's criteria, and results of the associated passenger-contacts' TB screening tests. The economic analysis compared the costs of TBCIs to avoided costs of TB treatment and mortality using a Return on Investment model. Results: The estimated in-flight transmission risk using a modified CDC protocol was 1.4%-19% versus 1.1%-24% for the 2008 protocol. Numbers of TBCIs and immediate costs to health departments were reduced by half. Long-term costebenefits were comparable. Conclusions: CDC's modified protocol appears to be a feasible alternative that will conserve public health resources without jeopardizing the public's health. [ABSTRACT FROM AUTHOR]