The scenario is not unexpected. Here’s how it could have happened.
The story of an emergency nurse who tested positive for COVID-19 after receiving the vaccine is a reminder that hand washing, social distance and masks will continue to be crucial in 2021.
Matthew W., a 45-year-old nurse in San Diego, received the Pfizer vaccine on Dec. 18 and told ABC News in San Diego, KGTV, that the only side effect he was experiencing was arm pain.
Six days later, after working a shift in the COVID-19 unit, Matthew had chills, muscle aches and fatigue. A test in the hospital confirmed that he is positive for COVID-19.
The scenario is not unexpected, said dr. Christian Ramers, a specialist in infectious diseases at Family Health Centers of San Diego, told KGTV.
Patients do not develop COVID-19 protection immediately after being vaccinated.
“We know from clinical trials of the vaccine that it will take about 10 to 14 days before you start developing protection against the vaccine,” Ramers said.
Even after these 10 to 14 days, patients need a second dose of vaccine for full protection. “The first dose, according to us, gives you somewhere around 50%, and you need the second dose to get 95%,” Ramers added.
Another possibility: Since the incubation period for COVID-19 can last as long as 14 days, it is also possible that Matthew became infected before receiving the vaccine on 18 December.
Both potential scenarios are a reminder that vaccines are not a panacea. Instead, experts say, it will take time to end the pandemic and the continued adherence to fundamental public health practices such as social distance, masks and hand washing.
“You hear the health practitioners are very optimistic that this is the beginning of the end, but it’s going to be a slow roll, weeks to months as we roll out the vaccine,” Ramers said.
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