title: Endemic eastern equine encephalitis in the Amazon region of Peru.
abstract: Eastern equine encephalitis virus (EEEV) causes severe neurologic disease in North America, but only two fatal human cases have been documented in South America. To test the hypothesis that alphavirus heterologous antibodies cross-protect, animals were vaccinated against other alphaviruses and challenged up to 3 months later with EEEV. Short-lived cross-protection was detected, even in the absence of cross-neutralizing antibodies. To assess exposure to EEEV in Peru, sera from acutely ill and healthy persons were tested for EEEV and other alphavirus antibodies, as well as for virus isolation. No EEEV was isolated from patients living in an EEEV-enzootic area, and only 2% of individuals with febrile illness had EEEV-reactive IgM. Only 3% of healthy persons from the enzootic region had EEEV-neutralizing antibodies. Our results suggest that humans are exposed but do not develop apparent infection with EEEV because of poor infectivity and/or avirulence of South American strains.
authors.affiliation: Center for Biodefense and Emerging Infectious Diseases, Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas 77555-0609, USA.
authors.forename: Patricia V
authors.initials: PV
authors.lastname: Aguilar
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Robich
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Turell
authors.forename: Monica L
authors.initials: ML
authors.lastname: O'Guinn
authors.forename: Terry A
authors.initials: TA
authors.lastname: Klein
authors.forename: Alfredo
authors.initials: A
authors.lastname: Huaman
authors.forename: Carolina
authors.initials: C
authors.lastname: Guevara
authors.forename: Zonia
authors.initials: Z
authors.lastname: Rios
authors.forename: Robert B
authors.initials: RB
authors.lastname: Tesh
authors.forename: Douglas M
authors.initials: DM
authors.lastname: Watts
authors.forename: James
authors.initials: J
authors.lastname: Olson
authors.forename: Scott C
authors.initials: SC
authors.lastname: Weaver
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D006224:Cricetinae; D003429:Cross Reactions / Q000276:immunology; D004663:Encephalitis Virus, Eastern Equine / Q000276:immunology* / Q000472:pathogenicity; D004666:Encephalitis Virus, Venezuelan Equine / Q000276:immunology* / Q000472:pathogenicity; D004683:Encephalomyelitis, Equine / Q000453:epidemiology* / Q000276:immunology / Q000517:prevention & control / Q000821:virology; D019353:Endemic Diseases; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007114:Immunization; D008647:Mesocricetus; D051379:Mice; D009500:Neutralization Tests; D010568:Peru / Q000453:epidemiology; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral