The scenario is not unexpected. See how this could have happened.
The story of an emergency room nurse who tested positive for COVID-19 after receiving the vaccine is a reminder that hand washing, social distance and masks will still be crucial in 2021.
Matthew W., a 45-year-old nurse from San Diego, received the vaccine from Pfizer on December 18 and told KGTV, an affiliate of ABC News San Diego, that the only side effect of the vaccine he experienced was pain in his arm.
Six days later, after working a shift at the COVID-19 unit, Matthew experienced chills, muscle aches and fatigue. A hospital drive-up test confirmed that he was positive for COVID-19.
The outlook is not unexpected, Dr. Christian Ramers, an infectious disease specialist at the San Diego Family Health Centers, told KGTV.
Patients do not develop COVID-19 protection immediately after being vaccinated.
“We know from clinical vaccine tests that it will take about 10 to 14 days for you to start developing vaccine protection,” said Ramers.
Even after those 10 to 14 days, patients still need a second dose of the vaccine for full protection. “We believe that the first dose gives you around 50%, and you need the second dose to reach 95%,” added Ramers.
Another possibility: since the COVID-19 incubation period can be up to 14 days, it is also possible that Matthew was infected before receiving the vaccine on December 18.
Both potential scenarios are a reminder that vaccines are not a panacea. Instead, experts say, stopping the pandemic will take time and continued adherence to key public health practices, such as social detachment, masks and hand washing.
“You hear healthcare professionals being very optimistic about this being the beginning of the end, but it will be a slow process, weeks to months as we launch the vaccine,” said Ramers.
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