RESUMEN
Japanese encephalitis virus (JEV) is a major threat to human health. Bangladesh is considering introducing a JEV vaccine; however, the investment case is hampered by a limited understanding of key aspects of JEV ecology. We conducted a seroprevalence study in a high-incidence region using an assay that limits cross-reactivity with dengue virus. We also trapped mosquitoes and collected information about potential host species. We used mathematical models to recover risk factors for infection and underlying probabilities of severe disease and death. We observed 19.0% [95% confidence interval (CI):17.1 to 21.1] of JEV antibodies. On average, 0.7% (95% CI: 0.2 to 2.0) of the susceptible population gets infected yearly, with pig proximity being the main human infection risk factor. Our traps captured 10 different mosquito species that have been linked with JEV transmission. We estimated that 1 in 1000 infections results in severe disease, 1 in 10,000 results in death, and 76% of severe cases are missed by surveillance.
Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Vacunas contra la Encefalitis Japonesa , Bangladesh/epidemiología , Humanos , Encefalitis Japonesa/epidemiología , Encefalitis Japonesa/prevención & control , Encefalitis Japonesa/transmisión , Vacunas contra la Encefalitis Japonesa/inmunología , Virus de la Encefalitis Japonesa (Especie)/inmunología , Animales , Estudios Seroepidemiológicos , Adolescente , Adulto , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Niño , Masculino , Femenino , Adulto Joven , Preescolar , Persona de Mediana Edad , Culicidae/virología , Mosquitos Vectores/virologíaRESUMEN
Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.
Asunto(s)
Mpox , Minorías Sexuales y de Género , Masculino , Humanos , Portugal/epidemiología , Homosexualidad Masculina , Brotes de Enfermedades , Análisis por ConglomeradosRESUMEN
Introduction: Health professionals face higher occupational exposure to SARS-CoV-2. We aimed to estimate the risk of COVID-19 test positivity in health professionals compared to non-health professionals. Methods: We conducted a test-negative case-control study using Portuguese national surveillance data (January to May 2020). Cases were suspected cases who tested positive for SARS-CoV-2; controls were suspected cases who tested negative. We used multivariable logistic regression modelling to estimate the odds ratio of a positive COVID-19 test (RT-PCR; primary outcome), comparing health professionals and non-health professionals (primary exposure), and adjusting for the confounding effect of demographic, clinical, and epidemiological characteristics, and the modification effect of the self-reported epidemiological link (i.e., self-reported contact with a COVID-19 case or person with COVID-19-like symptoms). Results: Health professionals had a 2-fold higher risk of a positive COVID-19 test result (aOR = 1.89, 95% CI 1.69-2.11). However, this association was strongly modified by the self-report of an epidemiological link such that, among cases who did report an epidemiological link, being a health professional was a protective factor (aOR = 0.90, 95% CI 0.82-0.98). Conclusion: Our findings suggest that health professionals might be primarily infected by unknown contacts, plausibly in the healthcare setting, but also that their occupational exposure does not systematically translate into a higher risk of transmission. We suggest that this could be interpreted in light of different types and timing of exposure, and variability in risk perception and associated preventive behaviours.
Introdução: Os profissionais de saúde têm uma maior exposição profissional à SARS-CoV-2. O objetivo era estimar o risco de testar positivo para SARS-CoV-2 em profissionais de saúde. Métodos: Foi realizado um estudo testenegativo caso-controlo utilizando os dados de vigilância epidemiológica nacional (JaneiroMaio 2020). Casos foram definidos como casos suspeitos que testaram positivo para SARS-CoV-2 (RTPCR), e os controlos como casos suspeitos que testaram negativo. Foi aplicado um modelo de regressão logística multivariável para estimar o odds ratio de teste positivo para SARS-CoV-2, comparando profissionais de saúde e não profissionais de saúde, ajustado para as características demográficas, clínicas e epidemiológicas, e a modificação de efeito com o autorrelato duma ligação epidemiológica (i.e., contacto auto-reportado com um caso COVID-19 ou uma pessoa com sintomas semelhantes aos da COVID-19). Resultados: Os profissionais de saúde tiveram um risco duas vezes maior de testar positivo para SARS-CoV-2 (aOR = 1.89, 95% CI 1.692.11). No entanto, esta associação era fortemente modificada pelo autorrelato de uma ligação epidemiológica, de tal forma que entre os casos que relataram uma ligação epidemiológica, ser profissional de saúde revelou-se fator de proteção (aOR = 0.90, 95% CI 0.820.98). Conclusão: Os nossos resultados sugerem que os profissionais de saúde podem estar infetados principalmente por contactos desconhecidos, plausivelmente em instituições de saúde, e a exposição profissional não se traduz sistematicamente num maior risco de transmissão. Isto poderá ser interpretado à luz de diferentes tipos e tempos de exposição, e da variabilidade na perceção do risco e dos comportamentos preventivos associados.