Senecavirus A (SVA) belonging to the family Picornaviridae, genus Senecavirus was incidentally isolated in 2002 from the PER.C6 (transformed foetal retinoblast) cell line. However, currently, this virus is associated with vesicular disease in swine and it has been reported in countries such as the United States of America, Canada, China, Thailand and Colombia. In Brazil, the SVA was firstly reported in 2015 in outbreaks of vesicular disease in swine, clinically indistinguishable of Foot‐and‐mouth disease, a contagious viral disease that generates substantial economic losses. In the present work, it was standardized a diagnostic tool for SVA based on RNA reverse transcriptase droplet digital PCR (RT‐ddPCR) using one‐step and two‐step approaches. Analytical sensitivity and specificity were done in parallel with real‐time PCR, RT‐qPCR (one‐step and two‐step) for comparison of sensitivity and specificity of both methods. In the standardization of RT‐ddPCR, the double‐quenched probe and the temperature gradient were crucial to reduce background and improve amplitude between positive and negative droplets. The limit of detection and analytical specificity of techniques of one‐step techniques showed superior performance than two‐step methods described here. Additionally, the results showed 94.2% concordance (p < 0.001) for RT‐ddPCR and RT‐qPCR using the one‐step assay approach and biological samples from Brazilian outbreaks of Senecavirus A. However, ddRT‐PCR had a better performance than RT‐PCR when swine serum pools were tested. According to the results, the one‐step RT‐ddPCR and RT‐qPCR is highlighted to be used as an auxiliary diagnostic tool for Senecavirus A and for viral RNA absolute quantification in biological samples (RT‐ddPCR), being a useful tool for vesicular diseases control programs.

BACKGROUNDThe World Health Organization (WHO) has classified human zoonotic tuberculosis (TB) due to Mycobacterium bovis as a neglected issue in the developing world. In a recent cross-sectional study in Brazil, three of 189 TB patients presented with a coinfection of M. bovis and M. tuberculosis and were selected as cases for this study.OBJECTIVEThe aim was to evaluate risk factors (RF) for zoonotic TB in an urban area of Brazil in order to guide preventive programmes.METHODSA matched case-control study was carried out nested within a cross-sectional study. For each of the three cases, 14 age- and sex-matched controls (TB due to M. tuberculosis) were selected.FINDINGSZoonotic potential exposures (ZE) and extrapulmonary TB (EPTB) were independently associated with zoonotic TB in multivariate analyses.CONCLUSIONSZE by occupation and consumption of raw milk and derivative products that place individuals in direct and indirect contact with animals and their excretions/secretions increase the risk for zoonotic TB in Brazil, especially among those with EPTB. Therefore, measures such as efficient control of bovine TB, distribution of pasteurised milk and its derivative products, and the diagnosis and monitoring of zoonotic TB in humans are essential steps, especially in developing countries where bovine TB is enzootic, and further studies are necessary.

Introduction: In Brazil, West Nile virus (WNV) was first detected, in 2018, in horses with neurological disease. Aim: We report the first case of WNV infection in a horse from Ceará state and the complete genome sequence of an isolate from Espírito Santo state. Both infections occurred in 2019. Methods: WNV was isolated from the tissues of a horse with neurological signs in Espírito Santo and sequenced by MiSeq. Results: Phylogenetic analysis revealed that the isolate belongs to lineage 1a, clustering with the NY99 strain, a strain that has not circulated in the USA since 2005. Conclusions: Our findings reinforce the hypothesis that WNV has been silently circulating in Brazil for many years.