"For the health and well-being of all tournament participants and people within the community, the Tour is implementing its response plan in consultation with medical experts, including working with those who may have had close contact with him, "the statement said.
McCarthy said he felt tired on Thursday, but thought it was because of how hard he practiced earlier in the week.
"Last night I woke up in the middle of the night with extra aches and pains and felt something was wrong," said McCarthy. & # 39; I felt that all I had to do was get tested at the time before going to the course. & # 39;
The PGA said McCarthy will isolate himself and follow the Centers for Disease Control and Prevention guidelines.
The PGA said 16 others were tested, including McCarthy's caddy, the two players who played next to him during the first round, Matt Wallace and Bud Cauley, and their caddies. McCarthy was the only positive result, but Cauley decided to withdraw as a precaution.
"I am very grateful that I tested negative, but I have decided to withdraw from an abundance of caution for my peers and anyone involved in the tournament," said Cauley.
"What Denny, Bud and others demonstrate is exactly what we've asked everyone to do: keep doing your bit to take this virus seriously and keep your health as a priority, as well as yours fellow competitors and those you may come into contact with, "said Jay Monahan, PGA Tour Commissioner.
" We will continue to interact directly with local and regional authorities this week and during our return to golf. and health officials, "he said.
Last week, golfer Nick Watney tested positive at the RBC Heritage tournament, and Cameron Champ tested positive earlier this week.