Cryptosporidium parvum en animales domésticos y en monos de un zoológico / Cryptosporidium parvum in domestic animals and in monkeys from a zoo

El objetivo del trabajo fue detectar infecciones por Cryptosporidium sp en animales domésticos y en monos de un zoológico, en la provincia de Buenos Aires, Argentina. Se procesaron 375 muestras de materia fecal de distintas especies mediante la técnica de sedimentación de Ritchie modificada (formol -éter) para concentrar los ooquistes. El sedimento se tiñó mediante la técnica de Ziehl-Neelsen modificada. Se detectaron ooquistes de Cryptosporidium sp en 7 de 175 muestras de materia fecal de perro, en 2 de 17 de gato, en 4 de 22 de ovinos, en 21 de 131 cabras, en 29 de 109 de terneros, en 2 de 2 de equinos y en 2 de 5 de cobayos (Cavia porcellus). Se examinaron 14 muestras de heces de monos, entre ellas, se detectaron ooquistes en la muestra de 1 hembra carayá (Alouatta caraya) adulta, en la de 1 mono araña (Ateles paniscus) macho adulto, en la muestra colectiva de 7 monos saimiri (Saimiri boliviensis) adultos, en la muestra de 2 hembras y 1 macho caí (Cebus apella), en la muestra colectiva de hamadríades (Papio hamadryas) y en la de 1 chimpancé joven (Pan troglodytes).

Aotus infulatus monkey is susceptible to Plasmodium falciparum infection and may constitute an alternative experimental model for malaria

Aotus is one of the WHO-recommended primate models for studies in malaria, and several species can be infected with Plasmodium falciparum or P. vivax. Here we describe the successful infection of the species A. infulatus from eastern Amazon with blood stages of P. falciparum. Both intact and splenectomized animals were susceptible to infection; the intact ones were able to keep parasitemias at lower levels for several days, but developed complications such as severe anemia; splenectomized monkeys developed higher parasitemias but no major complications. We conclude that A. infulatus is susceptible to P. falciparum infection and may represent an alternative model for studies in malaria.

Ultrastructural study on experimental infection of rotavirus in a murine heterologous model

Viral replication, histopathological and ultrastructural changes were observed for a period of nine days in the small intestine of suckling mice infected with a simian rotavirus (SA11). Samples taken from duodenum, jejunun and ileum were prepared for light microscopy, transmission and scanning electron microscopy analysis. Histopathologic effect could be detected within 8 hr post-infection, when only a few altered cells were observed. Damage was extensive after 16 hr post-infection, showing swollen enterocytes and reduced and irregularly oriented microvilli at intestinal villi tips. Virus particles were detected at 16 and 48 hr post-infection, budding from the viroplasm into the rough endoplasmic reticulum cisternae in ileum enterocytes. Clear evidence of viral replication, observed by electron microscopy was not described before in heterologous murine models. Regeneration of the intestinal villi began at the third day post-infection. Despite some differences observed in clinical symptoms and microscopic analysis of homologous and heterologous rotavirus infections, we concluded that mechanisms of heterologous rotavirus infection in mice follow similar patterns to those observed in the homologous models.