What's Eating You? Culex Mosquitoes and West Nile Virus.

West Nile virus (WNV) commonly presents cutaneously as a maculopapular rash on the trunk and extremities that most often appears around the time of defervescence and may serve as a positive prognostic indicator. Several laboratory tests can aid in diagnosis of WNV, including an IgM enzyme-linked immunosorbent assay (ELISA), but an antibody response may not be detectable for up to 8 days after symptom onset. Taking a comprehensive history in any patient presenting with a generalized maculopapular rash, fever, nonspecific symptoms, or neurologic changes can aid the astute dermatologist in promptly recognizing the possibility of WNV.