6 fully vaccinated people caught the Delta variant after an outdoor wedding, but the ones with Pfizer and Moderna shots didn't get very sick

• 6 fully vaccinated people came down with the Delta variant of COVID-19 after attending an outdoor wedding in Texas.
• All of the breakthrough infections were in guests over the age of 50.
• There were two serious cases (including one death) in attendees who'd gotten India's Covaxin vaccine.
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Six fully vaccinated people contracted COVID-19 at an outdoor wedding in Texas - a small outbreak that, above all, underscores how effective US-authorized vaccines are against even variants of the virus.

Though the vaccines by Pfizer and Moderna may not knock out every COVID-19 case, especially now that the more infectious Delta variant dominates across the US, they are very good at preventing serious illness and death from COVID-19.

According to the preprint study from Baylor College of Medicine, only those who'd gotten an Indian vaccine (Covaxin) fell severely ill after the 92-person event near Houston, Texas, in April.

The wedding took place inside a "large, open air tent," before the Delta variant was circulating widely across the US.

The study authors suspect that the Delta variant was introduced into the wedding by two patients who were traveling from India, and who had tested negative before boarding their flight, but developed symptoms once they landed in the US.

Infections were mild in attendees who had Pfizer, Moderna

All six of the wedding guests who contracted symptomatic cases of COVID-19 after the wedding were over the age of 50. Two of them had Pfizer, two had Moderna, and two had an Indian vaccine called Covaxin. Their infections were also confirmed with lab tests and viral sequencing for Delta.

Each patient experienced some common signs of a COVID-19 illness, including fever, cough, fatigue, and body aches. Those who'd gotten Moderna and Covaxin also lost their sense of smell.

But only the Covaxin recipients suffered truly severe infections: One was hospitalized and given Regeneron's monoclonal antibody treatment (the same one President Trump received) 10 days after the wedding. The other later died from complications of COVID-19.

Vaccines prevent death and severe sickness

US Centers for Disease Control and Prevention director Rochelle Walensky has stressed that vaccinated people should still get a COVID-19 test, if they experience upper respiratory symptoms like a runny nose, sore throat, or cough, which can be indicative of a mild Delta infection among fully vaccinated people.

"What I would say is: If you have those upper respiratory symptoms and you've been vaccinated, you should absolutely get a COVID-19 test," Walensky said during a White House COVID-19 briefing last week.

But, she also stressed that preliminary data from the past few months suggests that 99.5% of coronavirus deaths in the US are occuring in unvaccinated people.

"Those deaths were preventable with a simple, safe shot," she said.

During the briefing, Dr. Fauci, President Biden's chief medical advisor, also pointed to real-world data from Scotland and England suggesting that the currently authorized US vaccines are highly effective at preventing the most disastrous cases of this variant.

"Please get vaccinated," Fauci said. "It will protect you against the surging of the Delta variant."