He was vaccinated with the Pfizer vaccine and contracted coronavirus

A 45-year-old nurse tested positive for COVID-19 in California more than a week after receiving Pfizer’s coronavirus vaccine.

Matthew W., a nurse at two different hospitals, said in a Facebook post on Dec. 18 that he had received the vaccine, adding that his arm had been sore for a day, but had not suffered any other side effects.

Six days later, he fell ill after working a shift in the COVID-19 unit: he experienced chills, muscle pain and fatigue. He was tested in a hospital and came back positive.

Christian Ramers, an infectious disease specialist at San Diego Family Health Centers, said the possibility was not unexpected.

“We know from clinical trials of the vaccine that it will take 10-14 days to start developing protection with the vaccine,” he said: “We think that first dose gives you around 50% and that you need a second dose to reach 95% ”.

Regulators of the Pfizer vaccine have found that the best immunity against the coronavirus occurs seven days after the second dose, which is applied three weeks after the first. Thus, it is possible that a person who received the vaccine will contract the virus within this time. All patients need two doses of the vaccine to achieve immunity.