(Portland, OR) -- Oregon Senator Jeff Merkley says his battle against COVID-19 continues. He took the antiviral drug Paxlovid and his symptoms improved. But, like some patients who take Paxlovid, he is experiencing COVID-19 rebound. He again tested positive for COVID-19 with mild symptoms. Merkley is following CDC guidelines to isolate. He says it's another reminder that the virus is evolving and it's important to be vaccinated with boosters, wear masks, and isolate after testing positive.