Breakthrough infections with coronavirus mutants have been reported, but cases appear mild

Two reports of breakthrough infections of the so-called coronavirus (fully vaccinated people get sick anyway) provide strong protection against serious illness in the face of mutants of the vaccine. It suggests that.

Case explained in detail on Wednesday New England Journal of MedicineWas from two of the more than 400 fully vaccinated study participants who were tested for Covid-19 weekly. Both women developed mild cases and recovered quickly.

Complete coverage of coronavirus outbreaks

Dr. Robert Darnell, a professor and senior physician at Rockefeller University in New York City, who co-authored the study, said the two cases should not be wary.

“They certainly didn’t have to be hospitalized,” he said. “They had a home case of Covid-19.”

As the number of fully vaccinated people in the United States increases, so will reports of breakthrough infectious diseases.Centers for Disease Control and Prevention said it received on Friday Report Approximately 5,800 breakthrough infectious diseases out of more than 77 million complete vaccinated individuals.

Breakthrough infections can occur because there is no 100% effective vaccine. Such cases remain very rare.

CDC staff are collecting more data on breakthrough cases to determine if there is a pattern. Some of the questions are whether a particular variant is likely to play a role in a breakthrough case.

Both cases of the new report sequence, And both were found to share a particular mutation with the first identified mutant in the United Kingdom and New York. However, neither contained all mutations that matched the previously identified variant. (The virus variant may contain several mutations.)

Experts warned that it is too early to conclude which variant is most likely to lead to a breakthrough infection, as the report details only two cases.

One of the samples contained a mutation called E484K, which is also found in South African variants. Brazil And New York City. It is believed to help the virus avoid the body’s immune response to some extent.

Jeremy Kamil, a virologist at LSU Health Shreveport, Louisiana, wasn’t surprised that the mutation was detected, as laboratory data suggest that it plays a role in breakthrough cases. Said that.

“When I ask scientists what mutations are expected to be seen in breakthrough infections, I think the best answer is E484K,” Kamil, who was not involved in the new study. Said.

Two other studies published Wednesday in the CDC’s Weekly Morbidity and Mortality Report touched on breakthrough infections in nursing homes. One report From December to March, we identified 22 breakthrough infections in 78 nursing homes in the Chicago area that fully vaccinated approximately 15,000 residents and staff. In two-thirds of the breakthrough cases, the infection was asymptomatic, but several developed mild to moderate symptoms, the report said. Two patients were hospitalized and one died.

download NBC News App To completely cover the outbreak of coronavirus

The· Second report We focused on Covid-19, which occurred in a nursing home in Kentucky in March. Twenty-six residents and 20 staff were positive, including 18 fully vaccinated residents and 4 staff. Case sequencing detected the same E484K mutation as in the New York case.

However, vaccinated people were 87% less likely to develop symptoms than unvaccinated people.

“The results of this study show that vaccination reduced the likelihood of infections and symptomatic diseases in high-risk populations,” said Jason Kindrachuk, assistant professor of medical microbiology and infectious diseases at the University of Manitoba. I am. ” At Winnipeg.

Similarly, women listed in the New England Journal of Medicine report also had mild symptoms, Kindrachuk, who was not involved in the new report, said. “Vaccines did exactly what we expected based on clinical trial data and real-world data. They protected them from serious illness.”

A healthy 51-year-old woman, one of the patients in the New England Journal of Medicine Report, tested positive for Covid-19 on March 10, 19 days after the second dose of the modelna vaccine. She said she followed guidelines, including masking and social distance, but developed symptoms such as sore throat, congestion, and headaches. The day after the test, she lost her sense of smell. All her symptoms disappeared after a week.

The second patient, a 65-year-old woman, was free of severe Covid-19 risk factors and tested positive on March 17, 36 days after the second dose of the Pfizer-BioNTech vaccine. She became ill two weeks after her unvaccinated partner was diagnosed with Covid-19.

Her symptoms included malaise, sinus congestion, and headaches. As in the first case, her symptoms disappeared in just a few days.

CDC data suggest that breakthrough infections are rare, but Darnell tests for Covid-19 if fully vaccinated people develop disease-like symptoms. He said it was wise to receive.

“If you get sick after vaccination and look, smell and hear Covid-19, you may have Covid-19,” he said.

follow us NBC Health on twitter & Facebook..