Evidence against Zika virus infection of pets and peri-domestic animals in Latin America and Africa.

Decades after its discovery in East Africa, Zika virus (ZIKV) emerged in Brazil in 2013 and infected millions of people during intense urban transmission. Whether vertebrates other than humans are involved in ZIKV transmission cycles remained unclear. Here, we investigate the role of different animals as ZIKV reservoirs by testing 1723 sera of pets, peri-domestic animals and African non-human primates (NHP) sampled during 2013-2018 in Brazil and 2006-2016 in Côte d'Ivoire. Exhaustive neutralization testing substantiated co-circulation of multiple flaviviruses and failed to confirm ZIKV infection in pets or peri-domestic animals in Côte d'Ivoire (n=259) and Brazil (n=1416). In contrast, ZIKV seroprevalence was 22.2% (2/9, 95% CI, 2.8-60.1) in West African chimpanzees (Pan troglodytes verus) and 11.1% (1/9, 95% CI, 0.3-48.3) in king colobus (Colobus polycomos). Our results indicate that while NHP may represent ZIKV reservoirs in Africa, pets or peri-domestic animals likely do not play a role in ZIKV transmission cycles.

Ecologic Determinants of West Nile Virus Seroprevalence among Equids, Brazil.

Among 713 equids sampled in northeastern Brazil during 2013-2018, West Nile virus seroprevalence was 4.5% (95% CI 3.1%-6.3%). Mathematical modeling substantiated higher seroprevalence adjacent to an avian migratory route and in areas characterized by forest loss, implying increased risk for zoonotic infections in disturbed areas.

Identification of animal hosts of Fort Sherman virus, a New World zoonotic orthobunyavirus.

An orthobunyavirus termed Fort Sherman virus (FSV) was isolated in 1985 from a febrile US soldier in Panama, yet potential animal reservoirs remained unknown. We investigated sera from 192 clinically healthy peri-domestic animals sampled in northeastern Brazil during 2014-2018 by broadly reactive RT-PCR for orthobunyavirus RNA, including 50 cattle, 57 sheep, 35 goats and 50 horses. One horse sampled in 2018 was positive (0.5%; 95% CI, 0.01-3.2) at 6.2 × 103 viral RNA copies/mL. Genomic comparisons following virus isolation in Vero cells and deep sequencing revealed high identity of translated amino acid sequences between the new orthobunyavirus and the Panamanian FSV prototype (genes: L, 98.8%; M, 83.5%; S, 100%), suggesting these viruses are conspecific. Database comparisons revealed even higher genomic identity between the Brazilian FSV and taxonomically unassigned Argentinian mosquito- and horse-derived viruses sampled in 1965, 1982 and 2013 with only 1.1% maximum translated amino acid distances across viral genes, suggesting the Argentinian viruses were also distinct FSV strains. The Panamanian FSV strain was an M gene reassortant relative to all Southern American FSV strains, clustering phylogenetically with Cache Valley virus (CVV). Mean dN/dS ratios among FSV genes ranged from 0.03 to 0.07, compatible with strong purifying selection. FSV-specific neutralizing antibodies occurred at relatively high end-point titres in the range of 1:300 in 22.0% of horses (11 out of 50 animals), 8.0% of cattle (4/50 animals), 7.0% of sheep (4/57 animals) and 2.9% of goats (1/35 animals). High specificity of serologic testing was suggested by significantly higher overall FSV-specific compared to CVV- and Bunyamwera virus-specific end-point titres (p = .009), corroborating a broad vertebrate host range within peri-domestic animals. Growth kinetics using mosquito-, midge- and sandfly-derived cell lines suggested Aedes mosquitos as potential vectors. Our findings highlight the occurrence of FSV across a geographic range exceeding 7,000 km, surprising genomic conservation across a time span exceeding 50 years, M gene-based reassortment events, and the existence of multiple animal hosts of FSV.

Nem todo abscesso em pequenos ruminantes é causado por Corynebacterium pseudotuberculosis / Not all abscesses in small ruminants are caused by Corynebacterium pseudotuberculosis

O presente estudo objetivou determinar a prevalência e distribuição de lesões abscedativas, identificação do agente etiológico e avaliação das lesões histológicas em caprinos e ovinos abatidos em um matadouro-frigorífico com Serviço de Inspeção Federal do estado da Bahia. Foram coletadas 153 amostras de vísceras e linfonodos com abscessos de 1.148 animais abatidos. A maior prevalência na espécie ovina foi em macho, com faixa etária de 12 meses, sendo os principais órgãos acometidos fígado (21,2%) e linfonodo pré-escapular (20,3%). Na espécie caprina, a prevalência maior foi em macho, com faixa etária de 30 meses, sendo os linfonodos retro faríngeo (25%) e pré-escapular os mais acometidos (25%). Isolou-se os seguintes micro-organismos das amostras: Corynebacterium pseudotuberculosis em 33,33%, Escherichia coli (19,61%), Proteus mirabilis (9,80%), Pseudomonas aeruginosa (7,19%), Trueperella pyogenes (5,22%), Streptococcusspp. (5,22%) e Staphylococcus aureus (4,57%). As lesões macroscópicas e histológicas dos abscessos coletados não apresentaram diferenças entre micro-organismos isolados.(AU)

The study aimed to determine the prevalence and distribution of abscessed lesions, etiologic agent identification and assessment of histological lesions in sheep and goats slaughtered in a slaughter plant refrigerator with Federal Inspection Service in the State of Bahia. The amount of 153 samples of viscera and lymph nodes with abscesses of 1.148 slaughtered animals were collected. The highest prevalence in sheep was in males, aged 12 months, as in liver (21.2%) and prescapular lymph nodes (20.3%) the main affected organs. The prevalence in goats in male, aged 30 months and in retropharyngeal (25%) and prescapular lymph nodes (25%). The following microorganisms were isolated from the samples: Corynebacterium pseudotuberculosis 33.33%, Escherichia coli 19.61%, Proteus mirabilis 9.80%, Pseudomonas aeruginosa 7.19%, Trueperella pyogenes 5.22%, Streptococcus spp. 5.22% and Staphylococcus aureus 4.57%. The macroscopic and histological lesions of abscesses collected presented no difference between isolated microorganisms.(AU)