US nurse tests positive after taking first of 2-dose Pfizer vaccine
SAN DIEGO: A 45-year-old nurse in California tested positive for Covid-19 more than a week after receiving the first of the Pfizer's two-dose coronavirus vaccine, an ABC News affiliate reported on Tuesday.
But an infectious disease expert said this is not unexpected as the body needs time to develop protection.
Mr Matthew W, a nurse at two different local hospitals, said in a Facebook post on Dec 18 that he had received the Pfizer vaccine, telling the ABC News affiliate that his arm was sore for a day but that he had suffered no other side effects.
On Christmas Eve, he became sick after working a shift in the Covid-19 unit.
He got the chills and later came down with muscle aches and fatigue, Reuters reported.
He went to a drive-up hospital testing site and tested positive the day after Christmas Day.
Infectious disease specialist Christian Ramers with Family Health Centres of San Diego told the ABC News affiliate that this scenario was not a surprise.
"We know from the vaccine clinical trials that it's going to take about 10 to 14 days for you to start to develop protection from the vaccine," Dr Ramers said.
"That first dose we think gives you somewhere around 50 per cent and you need that second dose to get up to 95 per cent," Dr Ramers added.
The injections are taken 21 days apart.
He said it is possible that the nurse was infected even before receiving the vaccine.
Dr Ramers also said that he is aware of other cases where healthcare workers became infected around the time they received the vaccine, the Daily Mail reported.
He added that people should not let their guard down even if they have been vaccinated, and that they should continue to wash their hands and wear a mask, the New York Post reported.
"You hear health practitioners being very optimistic about it being the beginning of the end, but it's going to be a slow roll, weeks to months as we roll out the vaccine," Dr Ramers said.