A New Phlebovirus Associated with Severe Febrile Illness in Missouri

TLDR

Two men in northwestern Missouri developed fever, fatigue, diarrhea, thrombocytopenia, and leukopenia after tick bites. Next‑generation sequencing and phylogenetic analysis revealed the viruses to be novel phleboviruses. The novel phlebovirus is believed to be the cause of the clinical syndrome, though Koch's postulates remain incomplete.

Abstract

Two men from northwestern Missouri independently presented to a medical facility with fever, fatigue, diarrhea, thrombocytopenia, and leukopenia, and both had been bitten by ticks 5 to 7 days before the onset of illness. Ehrlichia chaffeensis was suspected as the causal agent but was not found on serologic analysis, polymerase-chain-reaction (PCR) assay, or cell culture. Electron microscopy revealed viruses consistent with members of the Bunyaviridae family. Next-generation sequencing and phylogenetic analysis identified the viruses as novel members of the phlebovirus genus. Although Koch's postulates have not been completely fulfilled, we believe that this phlebovirus, which is novel in the Americas, is the cause of this clinical syndrome.