The 49-year-old actress tweeted her condition, writing, "Dr. just called with blood test results...I have West Nile. Ugh. I'm fine, just tired. Takes a year to recover."
It's unknown where she contracted the illness, which can be spread by mosquitoes.
"Survivor: Philippines" wrapped its production in April. Approximately 5,000 Americans have been infected by the illness this year, and Texas, where Whelchel lives, is one of the hardest-hit states.
Whelchel later tweeted, "I've been very touched by all the sweet tweets. Other than tired, I'm feeling fine & expecting a full recovery. So grateful for you. Thanks!?"
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