A Transdisciplinary Approach to Managing Emerging and Resurging Mosquito-Borne Diseases in the Western Pacific Region

Prevalence and factors associated with persistent transmission of Schistosoma haematobium among primary school children after five rounds of mass drug administration using praziquantel: A cross sectional study in Mkuranga district, Tanzania

Despite a human schistosomiasis control programme through praziquantel mass drug administration (MDA) between 2011 and 2015,there was still persistent transmission among primary schoolchildren (PSC) in Mkuranga district, Tanzania. Our cross-sectional study was conducted among 396 PSC who provided urine for diagnosis of Schistosoma haematobium infection. Observations were conducted to determine PSC water contact activities. Logistic regression was used to test association between dependent and independent variables. We found MDA uptake among PSC as 72.5%, and the prevalence of Schistosoma haematobium infection 5.8%. The risk of infection increased among PSC engaged in fetching water and adjusted odds ratio (AOR) for swimming, bathing, fishing, crossing ponds and paddy fields were 0.123, 0.166, 0.232, 0.202 and 0.093 respectively. Thus we conclude that multiple water contact activities and low participation in MDA is responsible for persistent Schistosoma transmission.

A cocktail of human monoclonal antibodies broadly neutralizes North American rabies virus variants as a promising candidate for rabies post-exposure prophylaxis

Human rabies remains a globally significant public health problem. Replacement of polyclonal anti-rabies immunoglobulin (RIG), a passive component of rabies post-exposure prophylaxis (PEP), with a monoclonal antibody (MAb), would eliminate the cost and availability constraints associated with RIG. Our team has developed and licensed a human monoclonal antibody RAB1 (Rabishield^©), as the replacement for RIG where canine rabies is enzootic. However, for the highly diverse rabies viruses of North America, a cocktail containing two or more MAbs targeting different antigenic sites of the rabies glycoprotein should be included to ensure neutralization of all variants of the virus. In this study, two MAb cocktails, R172 (RAB1-RAB2) and R173 (RAB1-CR57), were identified and evaluated against a broad range of rabies variants from North America. R173 was found to be the most potent cocktail, as it neutralized all the tested North American RABV isolates and demonstrated broad coverage of isolates from both terrestrial and bat species. R173 could be a promising candidate as an alternative or replacement for RIG PEP in North America.

Utilizing citizen science to model the distribution of Aedes aegypti in West Africa

In the rapidly urbanizing region of West Africa, Aedes mosquitoes pose an emerging threat of infectious disease that is compounded by limited vector surveillance. Citizen science has been proposed as a way to fill surveillance gaps by training local residents to collect and share information on disease vectors. Understanding the distribution of arbovirus vectors in West Africa can inform researchers and public health officials on where to conduct disease surveillance and focus public health interventions. We utilized citizen science data collected through NASA's GLOBE Observer mobile phone application and data from a previously published literature review on Aedes mosquito distribution to examine the contribution of citizen science to understanding the distribution of Ae. aegypti in West Africa using Maximum Entropy modeling. Combining citizen science and literature-derived observations improved the fit of the model compared to models created by each data source alone but did not alleviate location bias within the models, likely due to lack of widespread observations. Understanding Ae. aegypti distribution will require greater investment in Aedes mosquito surveillance in the region, and citizen science should be utilized as a tool in this mission to increase the reach of surveillance.

Perceived discrimination in bateyes of the Dominican Republic: results from the Everyday Discrimination Scale and implications for public health programs

Background

Discrimination is a major driver of health disparities among minority groups and can impede the reach of public health programs. In the Dominican Republic, residents of bateyes, or agricultural ‘company towns,’ often face barriers to health care. This study examined the extent of perceived discrimination among batey populations and places the findings within the context of disease elimination efforts.

Methods

In March—April 2016, a stratified, multi-stage cluster survey that included the 9-item Everyday Discrimination Scale (EDS) was conducted among residents (n = 768) of bateyes across the Dominican Republic. Exploratory factor analysis, differential item functioning, and linear and logistic regression were used to assess associations between EDS scores, ethnic group status, reasons for discrimination, and healthcare-seeking behavior.

Results

Three ethnic groups were identified in the population: Haitian-born persons (42.5%), Dominican-born persons with Haitian descent (25.5%), and Dominican-born persons without Haitian descent (32.0%). Mean EDS scores (range 0–45) were highest among persons born in Haiti (18.2, 95% confidence interval [CI] = 16.4–20.1), followed by persons with Haitian descent (16.5, 95% CI = 14.9–18.0), and those without Haitian descent (13.3, 95% CI = 12.1–14.5). Higher EDS scores were significantly associated with Haitian birth (β = 6.8, 95% CI = 4.2—9.4; p < 0.001) and Haitian descent (β = 6.1, 95% CI = 3.2—9.0; p < 0.001). Most respondents (71.5%) had scores high enough to elicit reasons for their discrimination. Regardless of ethnic group, poverty was a common reason for discrimination, but Haitian-born and Haitian-descended people also attributed discrimination to their origin, documentation status, or skin color. EDS scores were not significantly associated with differences in reported care-seeking for recent fever (β = 1.7, 95% CI = − 1.4—4.9; p = 0.278).

Conclusion

Perceived discrimination is common among batey residents of all backgrounds but highest among Haitian-born people. Discrimination did not appear to be a primary barrier to care-seeking, suggesting other explanations for reduced care-seeking among Haitian populations. Public health community engagement strategies should avoid exacerbating stigma, build active participation in programs, and work towards community ownership of disease control and elimination goals.

Management of arthropod vector data - Social and ecological dynamics facing the One Health perspective

Emerging infectious diseases (EIDs) are spread by direct and/or indirect contacts between a pathogen or parasite and their hosts. Arthropod vectors have evolved as excellent bloodsuckers, providing an elegant transportation mode for a wide number of infectious agents. The nature of pathogen and parasite transfer and the models used to predict how a disease might spread are magnified in complexity when an arthropod vector is part of the disease cycle. One Health is a worldwide strategy for expanding interdisciplinary collaborations and communications in all aspects of health care for humans, animals and the environment. It would benefit from a structured analysis to address vectoring of arthropod-borne diseases as a dynamic transactional process. This review focused on how arthropod vector data can be used to better model and predict zoonotic disease outbreaks. With enhanced knowledge to describe arthropod vector disease transfer, researchers will have a better understanding about how to model disease outbreaks. As public health research evolves to include more social-ecological systems, the roles of society, ecology, epidemiology, pathogen/parasite evolution and animal behavior can be better captured in the research design. Overall, because of more collaborative data collection processes on arthropod vectors, disease modeling can better predict conditions where EIDs will occur.

Confronting the Emerging Threat to Public Health in Northern Australia of Neglected Indigenous Arboviruses

In excess of 75 arboviruses have been identified in Australia, some of which are now well established as causative agents of debilitating diseases. These include Ross River virus, Barmah Forest virus, and Murray Valley encephalitis virus, each of which may be detected by both antibody-based recognition and molecular typing. However, for most of the remaining arboviruses that may be associated with pathology in humans, routine tests are not available to diagnose infection. A number of these so-called 'neglected' or 'orphan' arboviruses that are indigenous to Australia might have been infecting humans at a regular rate for decades. Some of them may be associated with undifferentiated febrile illness-fever, the cause of which is not obvious-for which around half of all cases each year remain undiagnosed. This is of particular relevance to Northern Australia, given the Commonwealth Government's transformative vision for the midterm future of massive infrastructure investment in this region. An expansion of the industrial and business development of this previously underpopulated region is predicted. This is set to bring into intimate proximity infection-naïve human hosts, native reservoir animals, and vector mosquitoes, thereby creating a perfect storm for increased prevalence of infection with neglected Australian arboviruses. Moreover, the escalating rate and effects of climate change that are increasingly observed in the tropical north of the country are likely to lead to elevated numbers of arbovirus-transmitting mosquitoes. As a commensurate response, continuing assiduous attention to vector monitoring and control is required. In this overall context, improved epidemiological surveillance and diagnostic screening, including establishing novel, rapid pan-viral tests to facilitate early diagnosis and appropriate treatment of febrile primary care patients, should be considered a public health priority. Investment in a rigorous identification program would reduce the possibility of significant outbreaks of these indigenous arboviruses at a time when population growth accelerates in Northern Australia.