Hepato-pathological hallmarks for the surveillance of Yellow Fever in South American non-human primates.

The early detection and diagnosis of deaths in free-ranging non-human primates (NHPs) are key points for the surveillance of Yellow Fever (YF) in Brazil. The histopathological identification of infectious diseases remains very useful and reliable in the screening and detection of emerging zoonotic diseases such as YF. We surveyed data records and liver slides stained with hematoxylin and eosin from the Epizootics Surveillance Network to control YF, Ministry of Health of Brazil, to evaluate histopathological hallmarks for the diagnosis of the YF virus infection. We selected natural fatal cases in NHPs from the genera Alouatta spp., Callithrix spp., and Sapajus spp. with a positive immunohistochemical assay for YF in liver samples. Our findings showed the full-spectrum YF-associated hepatic lesions in all NHPs, but some histopathological findings differed in the distribution and intensity between the three genera. In our study, South American NHPs showed significant differences in the YF-associated hepatic histopathological features compared to fatal cases reported in humans.

Fatal Human Alphaherpesvirus 1 Infection in Free-Ranging Black-Tufted Marmosets in Anthropized Environments, Brazil, 2012-2019.

Human alphaherpesvirus 1 (HuAHV1) causes fatal neurologic infections in captive New World primates. To determine risks for interspecies transmission, we examined data for 13 free-ranging, black-tufted marmosets (Callithrix penicillata) that died of HuAHV1 infection and had been in close contact with humans in anthropized areas in Brazil during 2012-2019. We evaluated pathologic changes in the marmosets, localized virus and antigen, and assessed epidemiologic features. The main clinical findings were neurologic signs, necrotizing meningoencephalitis, and ulcerative glossitis; 1 animal had necrotizing hepatitis. Transmission electron microscopy revealed intranuclear herpetic inclusions, and immunostaining revealed HuAHV1 and herpesvirus particles in neurons, glial cells, tongue mucosal epithelium, and hepatocytes. PCR confirmed HuAHV1 infection. These findings illustrate how disruption of the One Health equilibrium in anthropized environments poses risks for interspecies virus transmission with potential spillover not only from animals to humans but also from humans to free-ranging nonhuman primates or other animals.

An undescribed species of Sarcocystis associated with necrotizing meningoencephalitis in naturally infected backyard chickens in the Midwest of Brazil.

Sarcocistys -associated menigoencephalitis is virtually an unrecognized cause of neurological disease in chickens. An undescribed species of Sarcocystis cause fatal infection in two backyard chickens in the Midwest of Brazil. Infected chickens presented anorexia, weight loss, incoordination, ataxia and opisthotonos. Yellow necrotic foci in the gray and white matter of the telencephalon were the main gross lesion. Microscopically, necrotizing granulomatous and heterophilic meningoencephalitis with intralesional Sarcocystis -like schizonts and mezoites were observed in the central nervous system. Molecular analysis of frozen brain samples of the two chickens was identical and the protozoan was named Sarcocystis sp. Chicken-2016-DF-BR. Complete nested PCR- sequence of Sarcocystis sp. Chicken-2016-DF-BR was equally similar to Sarcocystis anasi (EU553477) and Sarcocystis albifronsi (EU502868). This is the first report of Sarcocistys -associated meningoencephalitis with molecular characterization in backyard chickens.

[Susceptibility of the horn fly (Haematobia irritans) to insecticides in the Tabuleiros Costeiros region in states of Alagoas, Bahia and Sergipe, Brazil]. / Suscetibilidade da mosca-dos-chifres (Haematobia irritans) a inseticidas nos Tabuleiros Costeiros de Alagoas, Bahia e Sergipe, Brasil.

Susceptibility of horn fly populations to insecticides was evaluated at the Tabuleiros Costeiros region in the states of Alagoas, Bahia, and Sergipe from April 2001 to December 2002. A total of 37 bioassays were conducted in 23 ranches from 12 municipalities. Fly susceptibility was determined by the impregnated filter paper method using the active ingredients diazinon, permethrin, and cypermethrin. A high susceptibility to diazinon was found, with LC50 varying from 0.23 to 1.41 microg/cm2 and resistance ratios (RR) = 1.3. On the other hand, resistance to pyrethroids was detected in all studied populations. Cypermethrin LC50 ranged from 19.94 to 1,928 microg/cm2 and RR from 21.2 to 4,484.4. Although resistance levels to permethrin were much lower (RR<6), all LC50 were significantly higher than the LC50 obtained from the susceptible population. All ranches relied on pyrethroids for horn fly control, most cypermethrin (88.46%) and deltamethrin (80.77%) products. Spraying, by using manual backpack sprayers, was routinely used in all ranches. History of insecticide use as well as inadequate control practices help to explain the spread resistance of horn fly populations to pyrethroids detected in the region.