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