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All 86 wild boars (Sus scrofa), 170 hunting dogs, and 49 hunters sampled from three Brazilian regions were seronegative to Brucella spp. by the standard tube agglutination and 2-mercaptoethanol tests, suggesting a low circulation of Brucella spp. in wild boars, hunting dogs, and hunters in such areas., (© Wildlife Disease Association 2021.)

Rabies virus is recognized as one of the most fatal zoonotic agents affecting all mammals. Wild boars (Sus scrofa), classified as a large-size exotic invasive species in Brazil with nationwide hunting permitted, may serve as an extra blood source for the common vampire bat (Desmodus rotundus). Our aim was to document wild boar exposure to vampire bats to determine the seroprevalence of rabies virus antibodies in wild boars and to determine the immune status of hunters in southern and central-western Brazilian regions. Serum samples were collected from 80 wild boars and 49 hunters from natural and degraded areas of the Atlantic Forest biome of southern Brazil and in degraded areas of the Cerrado biome of central-western Brazil. The rabies-modified rapid fluorescent focus inhibition test was performed to detect the presence of rabies virus neutralizing antibodies in wild boars and considered seropositive when ≥0.10 IU/mL. The simplified fluorescence inhibition microtest was used for samples from hunters with a titer of ≥0.50 IU/mL and considered indicative of seroconversion. While 11% (9/80) of wild boars had serum titers for rabies exposure (≥0.10 IU/mL), 88% (43/49) of corresponding hunters lacked immune protective titers (<0.50 IU/mL). Wild boars showed serum titers for rabies likely due to contact with contaminated saliva of vampire bats or from infected carcass consumption. Additionally, Brazilian wild boars can be exposed to rabies and may play an important role in the sylvatic rabies cycle by providing a blood supply for vampire bats, highlighting the possibility of direct transmission of rabies virus to hunting dogs and hunters. These findings suggested hunters are a potential risk group for contracting rabies, and the World Health Organization may consider adding this occupation to their recommendations of who should receive the pre-exposure rabies vaccination., (© Wildlife Disease Association 2021.)

Hunting activities are a potential risk factor for human infection with Leptospira spp. and, although wild boar seroprevalence has been studied, there are no concurrent serosurveys of wild boars (Sus scrofa), hunting dogs (Canis lupus familiaris), and hunters. The aim of our study was to assess the seroprevalence of Leptospira spp. antibodies in free-ranging wild boars, hunting dogs, and hunters, and risk factors associated with exposure in southern and central-western Brazil. Leptospira spp. antibodies were serologically detected using the microscopic agglutination test, with a total 30 serovars. Overall, 12.2% (9/74) of wild boars and 10.6% (16/170) of hunting dogs were seropositive for at least one serovar and all hunters 0.0% (0/49) were seronegative for Leptospira spp. Seropositivity was statistically higher in 42.1% (8/19) wild boars from natural areas when compared to 2.4% (1/41) from anthropized areas (P<0.001), with prevalence ratio of 17.14 (95% confidence interval: 2.29-128.36). Despite the limited sample size, our findings showed that hunters may be less exposed to Leptospira spp. than are wild boars, particularly in natural areas where Leptospira spp. may be maintained by wild reservoirs. In addition to acting as sentinels, hunting dogs may play a role in disease transmission of sylvatic leptospiral serovars., (© Wildlife Disease Association 2021.)

Free-ranging wild boars (Sus scrofa) from two different Brazilian biomes were sampled. Only one of 36 (2.8%) animals tested from central-western Brazil were positive for antibodies against pseudorabies virus (PRV) by enzyme-linked immunosorbent assay. Peccaries and other wildlife species can be exposed to PRV in these areas. In addition, wild boars could have impact on livestock and PRV eradication., (© Wildlife Disease Association 2020.)

Mycoplasma ovis is a hemoplasma that may cause anemia and mortality in small ruminants. Our aim was to determine whether M. ovis infects populations of free-ranging deer in Brazil. Buffy coat samples from 64 Blastocerus dichotomus from Porto Primavera, 18 Ozotocerus bezoarticus from Pantanal, and 21 O. bezoarticus from Emas National Park were tested. Using a M. ovis PCR protocol to amplify extracted DNA, 46/64 (72%) of deer from Porto Primavera, 10/18 (56%) from Pantanal, and 4/21 (19%) from Emas National Park were positive, giving an overall positive rate of 58% for hemoplasma in these wild deer. Sequencing and phylogenetic analysis of the 16S rRNA gene revealed 3 genetically distinct hemoplasmas including M. ovis, 'Candidatus Mycoplasma erythrocervae', and a hemoplasma most closely related to M. ovis. Phylogenetic analysis of the 23S rRNA gene from selected sequences confirmed these relationships.