Australian vertebrate hosts of Japanese encephalitis virus: a review of the evidenceMoore, Kevin T; Mangan, Madelyn J; Linnegar, Belinda; Athni, Tejas S; McCallum, Hamish I; Trewin, Brendan J; Skinner, Eloise
doi: 10.1093/trstmh/trae079pmid: 39451055
Japanese encephalitis virus (JEV) transmission in temperate Australia has underscored a critical need to characterise transmission pathways and identify probable hosts of the virus. This systematic review consolidates existing research on the vertebrate hosts of JEV that are known to exist in Australia. Specifically, we aim to identify probable species involved in JEV transmission, their potential role as hosts and identify critical knowledge gaps. Data were extracted from studies involving experimental infection, seroprevalence and virus isolation and were available for 22 vertebrate species known to reside in Australia. A host competence score was calculated to assess the ability of each species to generate and sustain a viraemia. Based on the host competence score and ecology of each species, we find that ardeid birds, feral pigs and flying foxes have potential as maintenance hosts for JEV in the Australian context. We also note that domestic pigs are frequently infected during outbreaks, but their role as amplification hosts in Australia is unclear. Evidence to confirm these roles is sparse, emphasising the need for further targeted research. This review provides a foundation for future investigations into JEV transmission in Australia, advocating for enhanced surveillance and standardised research methodologies to better understand and mitigate the virus's impact.
Association between blood group antigens ABO, Rh, Kell, Kidd, Duffy and MNS and clinical forms of Chagas diseaseVizzoni, Alexandre G; da Costa, Andréa Rodrigues; Hasslocher-Moreno, Alejandro M; Mediano, Mauro Felippe F; Saraiva, Roberto M
doi: 10.1093/trstmh/trae096pmid: 39564954
BackgroundThe mechanisms that determine the progression to cardiac or digestive forms of chronic Chagas disease (CD) are still unclear. We assessed the association between blood group antigens ABO, Rh, Kell, Kidd, Duffy and MNS, and chronic CD clinical forms.MethodsPatients were included consecutively between March 2013 and April 2016. Clinical and epidemiological data were obtained from electronic medical records and interviews. Classification of CD clinical forms followed the Brazilian Consensus on CD. The ID-Gel Card technology from Bio-Rad (Diamed/Bio-Rad Latin America, MG, Brazil) was used to analyze the blood group antigens.ResultsA total of 619 adult patients (56.9% women, mean age 60±12 y) were included. Patients’ clinical forms of CD were classified as follows: indeterminate 29.1%, cardiac 55.4%, digestive 5.5% and mixed 10.0%. Logistic regression analysis adjusted for age, comorbidities and time away from an endemic area revealed that the S+s- allele of the MNS blood type was associated with a lower odds of cardiac disease and that the B blood group type was associated with a higher odds of digestive disease. All other blood types did not have an association with CD clinical form.ConclusionsBlood group systems ABO and MNS were associated with chronic CD clinical forms.
The dynamics of household sanitation services and faeco-oral diseases externalities in Osun State, southwest NigeriaAluko, O O
doi: 10.1093/trstmh/trae101pmid: 39558841
BackgroundMaintaining human dignity through sanitation is a perennial challenge and highlights the externalities of sanitation and hygiene services (SHS). In Nigeria, 23.2% practise open defecation, and 45.5% use basic sanitation services, although conventional sewerage systems are rare. This study determines SHS and their predictors in the context of local governance in southwest Nigeria.MethodsThe cross-sectional study applied a five-stage sampling technique and elicited information from 542 respondents using a validated semistructured questionnaire. The study results are presented by descriptive and inferential statistics.ResultsThe mean age of respondents was 48.2±0.8 y. Of these, 64.2% were homeowners, and 40.0% were in the lower wealth quartiles. While 76.9% of respondents had access to toilets, only 16.6% and 18.1% benefitted from safely managed and basic sanitation services, respectively, with 21.2% practising open defecation. Open defecation (42.6%) was prevalent primarily in the Ayedaade local government area (LGA), while safely managed sanitation services (27.6%) and limited sanitation services (54.1%) were predominant in the Olorunda and Ilesa-West LGAs. The predictors influencing household sanitation services included residence, ethnicity and wealth.ConclusionsThere were significant inequalities in sanitation access and critical infrastructure, and sanitation quality gaps exist among respondents. The prevalence of open defecation was high, and there was variation in access to sanitation services across different LGAs.
Distribution of the schistosome intermediate snail host Biomphalaria pfeifferi in East Africa's river systems and the prevalence of Schistosoma mansoni infectionMagero, Victor O; Kisara, Sammy; Suleman, Mbaruk A; Wade, Christopher M
doi: 10.1093/trstmh/trae115pmid: 39656884
BackgroundThere is a need for current and more detailed information on the distribution of Biomphalaria pfeifferi snails in East Africa's river systems. B. pfeifferi is arguably the most important snail intermediate host in the transmission of schistosomiasis, a disease ranked second to malaria in terms of tropical diseases of public health importance.MethodsWe assessed the occurrence and geographical distribution of B. pfeifferi snails in Kenya, Uganda and Tanzania. Maximum entropy modelling was used to predict the potential distribution of B. pfeifferi snails and malacological surveys were conducted guided by MaxEnt predictions and information from previous studies. Malacological surveys were conducted at a total of 172 sites, including streams, rivers, dams, irrigation schemes and springs over a 3-y period from 2018 to 2020, with geospatial, ecological and physicochemical information recorded for each site.ResultsB. pfeifferi snails were found at 23 of the 172 sites and inhabited a variety of habitat types. Of the 23 sites where B. pfeifferi snails were found, 15 (65.2%) were streams, 3 rivers (13.04%), 2 dams (8.7%), 2 springs (8.7%) and 1 an irrigation scheme (4.35%). B. pfeifferi abundance showed a significant positive correlation with increasing water temperature and decreasing water depth. In Kenya, B. pfeifferi snails were found around the Lake Victoria basin, the Mwea irrigation scheme and in parts of the former Eastern Province of Kenya. In Uganda, B. pfeifferi snails were found in Jinja District, Ntoroko District and Soroti District. In Tanzania, B. pfeifferi snails were found in the Iringa, Tabora and Kigoma Regions. We observed moderate to high prevalence of Schistosoma mansoni infection, with S. mansoni–infected snails found at 11 of 23 sites and with an average prevalence of 24.9% at infected sites. In Kenya, S. mansoni–infected snails were found in the Lake Victoria basin (22.5% prevalence at infected sites) and the former Eastern Province (13.5% prevalence at infected sites). In Uganda, infected snails were found in Ntoroko District (100% infected) and Soroti District (20% infected). In Tanzania, infected snails were found in the Kigoma Region, with a prevalence of 10% at the infected site.ConclusionThis information on the distribution of B. pfeifferi snails and S. mansoni infection in East Africa's river systems can aid in developing better prevention and control strategies for human schistosomiasis. Regular surveys of the river systems for snail intermediate hosts followed by molecular detection of schistosome infection could form a basis for the development of a prompt and cost-effective surveillance system for schistosomiasis in the region.