New Delhi: According to recent reports, a 45-year-old nurse in US' California has tested positive for Coronavirus within a week after he received the Pfizer Inc vaccine's shot. ALSO READ | Variation In Covid-19 Strains Will Not Make Vaccines Ineffective, Says Health Ministry


Matthew W. who works as a nurse at two different local hospitals revealed in a Facebook post on December 18 that he had received the Pfizer vaccine. As reported by news agency Reuters, he spoke to an ABC News affiliate where he informed that his arm was sore for a day but there were no other serious symptoms or side-effects.

However, on Christmas Eve, he fell sick after his shift ended in the Covid-19 unit. Barely six days after receiving the shot, he was experiencing muscle ache, fatigue, and was feeling cold.

After getting tested at a drive-up hospital, his results returned positive a day after Christmas, the report stated.

Speaking to the channel, an infectious disease specialist with Family Health Centers of San Diego, Christian Ramers, revealed the likely reason.

As per clinical trials, it takes 10 to 14 days for the protection against Coronavirus infection to begin developing, the doctor said. The first dose can provide around 50% immunity and only after the second shot does the receiver get up to 95% protection, Ramers added.

Hence, he deemed the case not really unexpected.

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