THE SUSCEPTIBILITY OF MARMOSETS TO YELLOW FEVER VIRUS.

Area of Science:

• Virology
• Tropical Medicine
• Primatology

Background:

• Yellow fever is a significant public health concern in tropical regions.
• Identifying suitable animal models is crucial for understanding yellow fever pathogenesis and developing countermeasures.

Purpose of the Study:

• To investigate the susceptibility of two Brazilian monkey species, Callithrix albicollis and Leontocebus ursulus, to yellow fever virus (YFV).
• To assess the potential of these species as models for YFV infection and transmission.

Main Methods:

• Introduction of YFV into marmosets via infected Aedes aegypti (Stegomyia) mosquito bites.
• Serial passages of the virus within each monkey species.
• Transmission back to rhesus monkeys via mosquito bites.
• Clinical observation, temperature monitoring, and post-mortem pathological examination of liver tissues.
• Evaluation of convalescent serum for protective antibodies.

Main Results:

• Leontocebus ursulus supported YFV replication, with four of five specimens developing fever and all succumbing to infection. Two L. ursulus specimens exhibited liver necrosis consistent with yellow fever.
• Callithrix albicollis showed limited susceptibility, with minimal temperature response in most individuals. None of the deceased C. albicollis displayed typical yellow fever lesions.
• Convalescent serum from C. albicollis conferred protection to rhesus monkeys, indicating the development of neutralizing antibodies.

Conclusions:

• Leontocebus ursulus serves as a susceptible model for yellow fever, displaying pathological changes similar to human infections.
• Callithrix albicollis, while less susceptible to severe disease, develops protective immunity, suggesting its potential utility in immunological studies.
• These findings contribute to the understanding of YFV host-pathogen interactions and the evaluation of potential animal models for yellow fever research.