A new study suggests that people who had been infected with COVID-19 prior to receiving the Pfizer vaccine may experience an adverse reaction post-vaccination.
Researchers analyzed 974 healthcare workers in the United Kingdom who received their first dose of the Pfizer-BioNTech vaccine, with study authors noting that around 265 of those recipients already had COVID-19 prior to receiving the shot.
The study identifies adverse events or AE's as "fever, fatigue, myalgia, arthralgia and lymphadenopathy" and states that those who had previously had COVID-19 were more likely to develop lymphadenopathy, or swollen lymph nodes, after the Pfizer vaccine than those who had not received it.
Roughly 4% of those who had already had COVID-19 reported this side effect after vaccination, as opposed to less than 1% of those who had not previously had the virus.
The study's authors concluded that "in a survey-based observational study, healthcare workers in the United Kingdom reported AEs experienced after their first dose of BNT162b2/Pfizer vaccine. Prior COVID-19 infection, but not Long-COVID, were associated with increased risk of self-reported AEs including lymphadenopathy post-vaccination," adding "duration since COVID-19 infection did not affect severity of AEs."
Among some of the AEs, the study suggested 8% of those who had COVID-19 experienced fever post-Pfizer-BioNTech vaccination, but only 2% who did not contract the virus previously contracted the fever post-vaccination.
The study also listed of the 974 participants, 84% were female with a mean age of 48.9. The research has not yet been peer-reviewed.
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