Reassortant Cache Valley Virus Associated With Acute Febrile, Nonneurologic Illness, Missouri.

An adult male from Missouri sought care for fever, fatigue, and gastrointestinal symptoms. He had leukopenia and thrombocytopenia and was treated for a presumed tickborne illness. His condition deteriorated with respiratory and renal failure, lactic acidosis, and hypotension. Next-generation sequencing and phylogenetic analysis identified a reassortant Cache Valley virus.