80 per cent COVID-19 immunity lost in 6 months in some after Pfizer shot: US study
Deccan ChronicleWashington: COVID-19 antibodies produced by the Pfizer vaccine decreased more than 80 per cent in senior nursing home residents and their caregivers six months after receiving their second dose, a US study has found. The research led by Case Western Reserve University and Brown University in the US studied blood samples of 120 nursing home residents and 92 health care workers. By six months after vaccination, the blood of 70 per cent of these nursing home residents had "very poor ability to neutralise the coronavirus infection in laboratory experiments," said David Canaday, a professor at the Case Western Reserve University. Early in the pandemic, higher COVID-19 mortality among nursing home residents in the US led to making them a priority for vaccination, the researchers said.