West Nile and St. Louis encephalitis viruses cause simultaneous outbreaks in Arizona, USA

There have been 46 cases and 3 deaths due to West Nile Fever in Maricopa County. At the same time, there have been 12 cases and possibly 1 death due to St. Louis encephalitis virus. It is unusual to have simultaneous outbreaks by these realatively rare viruses.

Visit our Health Library for more information on exposure to and the prevention of Encephalitis and West Nile Fever.

Advice For Travellers

Both West Nile Fever and St. Louis encephalitis are transmitted by mosquitoes. Travellers in this area should follow precautions to avoid mosquito bites.

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