Vaccinated US nurse contracts Covid, expert says Pfizer shot needed more time to work: Report

Six days later on Christmas Eve, he became sick after working a shift in the COVID-19 unit, the report added. He got the chills and later came down with muscle aches and fatigue.

He went to a drive-up hospital testing site and tested positive for COVID-19 the day after Christmas, the report said.

Christian Ramers, an infectious disease specialist with Family Health Centers of San Diego, told the ABC News affiliate that this scenario was not unexpected. “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,” Ramers said.

“That first dose we think gives you somewhere around 50%, and you need that second dose to get up to 95%,” Ramers added.