Statistics & Maps

Map of the U.S. showing Cache Valley virus disease cases. Cases have been identified in North Carolina, Missouri, Wisconsin, and New York.

As of 2021, cases of Cache Valley virus disease have been identified in North Carolina, Missouri, Wisconsin, and New York.

Cache Valley virus was named after the location in northern Utah where it was first detected in mosquitoes in 1956. Fewer than 10 cases of Cache Valley virus disease in humans have ever been reported.  They occurred in North Carolina, Missouri, Wisconsin, and New York. However, the virus has been found in mosquitoes in many places in North America and in parts of Central America. All have occurred in late spring through early fall.

Cache Valley virus disease is a nationally notifiable condition. Cases are reported to CDC by state and local health departments using the national surveillance case definition. To ensure standardization of reporting across the country, CDC recommends that the national surveillance case definition (standardized reporting criteria) be consistently applied by all state health departments.