Venezuelan Equine Encephalitis Virus Infection of Cotton Rats

• Main Authors: Anne-Sophie Carrara, Lark L. Coffey, Patricia V. Aguilar, Abelardo C. Moncayo, Amelia P.A. Travassos Da Rosa, Marcio R.T. Nunes, Robert B. Tesh, Nikos Vasilakis
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2007-08-01
• Series: Emerging Infectious Diseases
• Subjects: Encephalitis; alphavirus; reservoir host; cotton rat; arbovirus; research
• Online Access: https://wwwnc.cdc.gov/eid/article/13/8/06-1157_article
• ISSN: 1080-6040; 1080-6059

Venezuelan equine encephalitis virus (VEEV) is an emerging pathogen of equids and humans, but infection of its rodent reservoir hosts has received little study. To determine whether responses to infection vary among geographic populations, we inoculated 3 populations of cotton rats with 2 enzootic VEEV strains (Co97-0054 [enzootic ID subtype] and 68U201 [enzootic IE subtype]). The 3 populations were offspring from wild-caught cotton rats collected in a VEE-enzootic area of south Florida, USA; wild-caught cotton rats from a non–VEE-enzootic area of Texas, USA; and commercially available (Harlan) colony-reared cotton rats from a non–VEE-enzootic region. Although each population had similar early viremia titers, no detectable disease developed in the VEE-sympatric Florida animals, but severe disease and death affected the Texas and Harlan animals. Our findings suggest that the geographic origins of cotton rats are important determinants of the outcome of VEE infection and reservoir potential of these rodents.