Context:

  • Last year, the International Health Regulations National Focal Point (IHR NFP) in Argentina alerted the Pan American Health Organization/World Health Organization (PAHO/WHO) of a human case of Western Equine Encephalitis Virus (WEEV) infection.
  • Since then the outbreak has since grown to 21 confirmed new cases of the infection in Argentina.
  • The last cases of human infections in Argentina were reported in 1982, 1983, and an isolated event in 1996.

About Western Equine Encephalitis:

  • Western Equine Encephalitis is a mosquito­borne infection which is caused by the WEEV and it belongs to the Togaviridae family of viruses.
  • The virus has nearly 11.5 kilobases long single­stranded RNA genome.
  • The virus is a recombinant of the eastern equine encephalitis virus and a Sindbislike virus.
  • Passerine birds are thought to be the reservoir and equine species are intermediate hosts.
  • The primary mode of transmission of the infection to humans is through mosquitoes which act as vectors for the virus transmission.
  • While most of the infections are asymptomatic, the infection may lead to severe consequences in the rare cases.