Thomas Macias, 51, went to a barbecue last month in Lake Elsinore.
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Shortly after the party, he started feeling sick. On June 20, he posted a poignant message on Facebook to warn his loved ones about the risks of the virus, his family said.
"I went out a couple of weeks ago ... because of my stupidity I put my mom and sisters and my family's health in jeopardy," he wrote. "This has been a very painful experience. This is no joke. If you have to go out, wear a mask, and practice social distancing. ... Hopefully with God's help, I'll be able to survive this."
He never made it. He died a day after that post.
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A friend attended the party while sick
Macias worked as a truck driver and suffered from diabetes, making him especially vulnerable to the virus. Doctors have said people with underlying conditions such as diabetes, chronic lung disease and asthma are at a higher risk.
Before the barbecue, he had barely gone out, his brother-in-law Gustavo Lopez told CNN. But he was incredibly social and was feeling isolated, and decided to visit his friends when the state lifted some restrictions, he added.
"Everywhere he went he made friends instantly," Lopez said. "He was missing his friends and missing his family. So as soon as they lifted some of the restrictions he felt free and he unfortunately went to this get-together to be with his friends and then this was the result."
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A friend who was at the party reached out to Macias to say he had coronavirus, and he was aware of the diagnosis when he attended the gathering but didn't think he could infect anyone because he had no symptoms, Lopez said.
"Our understanding is that a gentleman had called him and said 'hey I was at the party, I knew I was positive. I didn't tell anybody,'" Lopez said. "I think the gentleman was regretting not telling everybody, and he was calling people who were at the party to recommend they get tested."
Macias was upset but blamed himself for the error in judgment, even using his Facebook post to warn friends about the dangers of the virus. About a dozen people who attended the party tested positive, Lopez said.
Macias got tested on June 15, got his positive result June 18 and died June 21. The Riverside County Office of Vital Records confirmed that he died of coronavirus.
Riverside County has over 18,000 confirmed coronavirus cases and about 460 deaths. It has the second-highest number of cases in the state after Los Angeles County.
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