Received: November 25, 2008.

Accepted: February 20, 2009.

Abstract published online: March 5, 2009.

Full paper published online: May 30, 2009.

ON THE INTERFERENCE OF CLINICAL OUTCOME ON RABIES TRANSMISSION AND PERPETUATION

Brandão PE (1)

(1) Department of Preventive Veterinary Medicine and Animal Health, School of Veterinary Medicine and Zootechny, University of São Paulo, USP, São Paulo, São Paulo State, Brazil.

ABSTRACT: Rabies is a viral zoonotic infectious disease that affects mammals and is caused by genotypes/species of the Lyssavirus genus (Rhabdoviridae, Mononegavirales), with the genotype 1 (classic rabies virus – RABV) being the most prevalent. Despite continuous efforts, rabies is still an incurable disease that causes thousands of deaths amongst humans worldwide. Due to a wide range of hosts and the different evolutionary paths of RABV in each host, several host-specific variants have arisen in an ongoing process. The result of RABV replication in nervous tissues may lead to two opposite clinical outcomes, i.e., paralytic/dumb form and encephalitic/furious one. The paralytic form creates dead-end hosts mainly amongst herbivores, while the furious form of the disease allows for augmented transmission when manifested in gregarious carnivores, as their natural aggressive behavior is accentuated by the disease itself. The aim of this article is to propose a theoretical model intended to explore how the rabies virus intrinsically modulates the immune system of different host classes, the pathological changes that the virus causes in these animals and how these elements favor its own perpetuation in nature, thus providing a basis for better prediction of the patterns this disease may present.

KEY WORDS: rabies, transmission, disease ecology, epidemiology, immune response.

CONFLICTS OF INTEREST: There is no conflict.

CORRESPONDENCE TO:

PAULO EDUARDO BRANDÃO, Departamento de Medicina Veterinária Preventiva e Saúde Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, 05508-270, Brasil. Phone: +55 11 3091 7655. Fax: +55 11 3091 7928. Email: paulo7926@usp.br.