Anthony Fauci, the former longtime director of the National Institute of Allergy and Infectious Diseases, was hospitalized with the West Nile Virus and is now recovering at home.
Fauci, who served on the White House Coronavirus Task Force, is expected to recover fully, a spokesperson told CNN.
The West Nile virus is the most common mosquito-spread disease in the continental US, with a median of over 2,200 cases being reported every year, according to the Department of Health and Human Services.
About 1,000 people are hospitalized each year with the most severe form of the disease, which if it spreads to the brain and nervous system, can cause brain swelling, brain damage and death.
There is no specific treatment for the virus or vaccine, but most cases are mild, where sufferers may experience flu-like symptoms or rashes.
The most likely time to contract the virus is in August and September, during the height of mosquito season.
As of August 20, there have been 216 West Nile virus cases in the US across 33 states, according to a CDC tracker.
About 65 percent of the total caseload have been reported to be neuroinvasive.