Dr. Anthony Fauci, former director of the National Institute of Allergy and Infectious Diseases, is recovering at home after being hospitalized with West Nile virus, a spokesperson said.

Fauci, a longtime public health official who became a household name as part of the White House Coronavirus Task Force, is expected to recover fully, the spokesperson said.

About 1,000 Americans are hospitalized each year with the most severe form of West Nile virus, which is the most common mosquito-borne disease in the continental United States. Another 1,500, on average, are diagnosed after developing symptoms, although experts estimate that as many of 80% of infections in the US are never identified.

“I really felt like I’d been hit by a truck,” Fauci told Stat on Saturday. “I have to tell you, I’ve never been as sick in my life. Ever. By far, this is the worst I’ve ever been with an illness.”

There is no vaccine or specific treatment for West Nile. Most cases are mild, causing flu-like symptoms and a rash. In about 1 in 150 cases, the virus invades the brain and nervous system, which can lead to brain swelling, brain damage or death. About 100 people die from West Nile infections in the US each year.

The heaviest virus activity is usually seen in August and September. As of August 20, 216 cases have been reported this year in 33 states, with 142 neuroinvasive cases, according to preliminary data from the US Centers for Disease Control and Prevention.

According to Stat, Fauci said he did not develop the neurological form of the illness. His temperature rose to 103 Fahrenheit and he said he experienced “shaking chills” and weakness.

“The good news is I’m absolutely going in the right direction,” he said. “The sobering news is that it’s going to take weeks and weeks to get back to normal. That’s the history of West Nile. It just wipes you out so badly.”

CNN’s Brenda Goodman contributed to this report.