Among travelers at risk, the presence of headache, elevated intracranial pressure, and pleocytosis, with or without eosinophilia, particularly in association with paresthesias or hyperesthesias, should alert clinicians to the possibility of A. cantonensis infection.

West Nile fever is a more severe illness than has previously been documented. Mandatory reporting of West Nile fever cases in addition to West Nile meningoencephalitis cases could allow more accurate and timely recognition of the geographic distribution of West Nile virus infections and could inform public health interventions.