Tomlinson, 75 -- who serves Bucks County and is the most veteran member of the Senate -- began experiencing mild flu-like symptoms last weekend, he said in a Facebook post Wednesday.
"After consultation with my doctor, I decided to get tested for COVID-19. Late last night, I received word that I tested positive," he wrote.
"I am feeling well, but I am currently quarantining. Just a reminder to all that you must continue to wear a mask, wash your hands, and use social distancing to help defeat the spread."
Tomlinson has represented the sixth district as a senator since 1995.
More than a dozen state lawmakers have tested positive for COVID-19 since early March, along with Gov. Tom Wolf, who tested positive in December.
As of 12 a.m., on Jan. 22, there were 5,338 additional positive cases of COVID-19 reported in Pennsylvania, bringing the statewide total to 794,172.
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