A mystery being investigated: how, why and when COVID vaccines are not completely protective

Ginger Eatman thought she was safe after getting her second COVID-19 vaccine in February. But she kept wearing her mask, using hand sanitizer and wiping the carts at the grocery store anyway. A few weeks later she noticed a itchy throat.

“By Wednesday morning, St. Patrick’s Day, I was sick. I had congestion – a lot of congestion – and coughing,” said Eatman, 73, of Dallas, GA.

Her doctor thought her symptoms might be allergies. But Eatman began to feel sicker. And then she suddenly lost her sense of smell. She even tried her strong perfume. Nothing.

Eatman was therefore tested for the coronavirus. It came back positive.

“I was shocked. I almost cried,” she says. “It was like, ‘No, it can not be.’

Eatman is not alone in this experience. It is a long recognized phenomenon called ‘vaccine breakthrough’.

“Essentially, these are cases that you see among vaccinated people during a period in which you expect the vaccines to work,” says Dr. Seed Omer, a vaccine researcher at Yale University. This incomplete protection that some people experience occurs to some extent with a vaccine against any disease.

The three vaccines authorized for use against COVID-19 in the United States appear to be at least 94 percent effective in preventing serious illness and death (approximately two weeks after a person fully vaccinated), according to data reported so far, and about 80 percent effective in preventing infection. But it’s not 100 percent, says Omer, so a relatively small number of infections can be expected despite vaccination with these very effective vaccines.

“So the end result is: it’s expected. No need to freak out,” Omer says.

To date, more than 74 million people in the United States have been completely vaccinated. It is unclear how much later became infected with the coronavirus anyway. But Michigan, Washington and other states have reported hundreds of cases. Most people became only slightly ill, but some became very ill. Some even died.

At a recent information session in the White House, dr. Anthony Fauci of the National Institutes of Health noted that such cases of lapse in full protection appear to be very rare. And it seems that the deaths occur mainly among debilitated elderly people with other health problems.

“There is nothing yet that is a red flag. We are, of course, going to watch it very, very closely. But I do not see anything that changes our concept of the vaccine and its effectiveness,” says Fauci.

And that is certainly no reason for anyone not to be vaccinated. The opposite is true.

“It seems like the rare infections are less serious, and it will also protect us from serious diseases, which is great,” says Dr. Francesca Torriani, a researcher in infectious diseases at the University of California, San Diego, who studied. breakthrough infections among health workers.

But such cases are a reminder of why it is important for people to be vigilant after being vaccinated, say contagious disease experts.

“I want to encourage people, as soon as they are vaccinated, to continue to use all the preventative measures we talked about when they are outside their home, including masking and distance and whatnot. And it all has to be active in the workplace,” “said the director of the Centers for Disease Control and Prevention, dr. Rochelle Walensky, told the press during an information session on Monday.

“If I accept that you are taking those precautionary measures at the office and outside the home, I think you are very safe in the home,” Walensky said.

Meanwhile, scientists are trying to figure out why breakthrough infections occur.

“At the moment, we do not have a good understanding of exactly where we are open – our kind of Achilles’ heel,” says Dr. Alexander Greninger, a researcher on infectious diseases at the University of Washington.

Is the determining factor to how much virus someone is exposed to? Or maybe exposure to one of the variants that can evade the immune system?

“Is it people in the lower part of the vaccine response who mix with the variants? I think it’s a little more – honestly – mysterious,” says Greninger.

Solving the mystery could help scientists improve the vaccines to prevent more breakthrough infections. Booster shots could be part of the answer, they say.

In turn, Eatman is still glad she was vaccinated. She recovered after about 10 days. But she has friends who were not nearly so happy – friends who have not been vaccinated.

“We had people at our church – some of them,” Eatman says. In one case, “after she became COVID, it quickly took her. And then another woman, just a little older than me, ended up in the hospital, the pneumonia in the ICU, outside the ICU, back in had the ICU. And she went home to be with the Lord. ”

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