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COVID-19: Pfizer Vaccine Only 39% Effective At Preventing Delta Variant Infection, Says Israel Govt

A recent Israeli study on Friday, revealed that Pfizer’s Covid-19 vaccine is less effective at preventing infection and symptomatic cases from Delta variant

Pfizer, Delta


In a worrying trend, a recent study by the Israeli health ministry on Friday, revealed that Pfizer’s Covid-19 vaccine is less effective at preventing infection and symptomatic cases from the Delta variant of the Coronavirus (COVID-19). The study stated that the Pfizer-BioNTech vaccine was 39% effective at preventing infections and 41% effective at preventing symptomatic infections from the Delta variant, which is lower than the early estimates of 64%. Pfizer is currently seeking US CDC's approval for a booster dose for those vaccinated.

Pfizer vaccine 39% effective against Delta variant

The study did reveal that the vaccination provided 92% protection against hospitalization and 91% protection against severe illness caused by the Delta variant, the ministry said. Israel has already allowed a booster shot of Pfizer vaccine to adults with weak immune systems. The Delta variant, which was first detected in India, has sent vaccination rates in Israel back up as new infections have risen over the past month from single digits to around 450 a day. Israel’s Health Minister Nitzan Horowitz announced that adults with impaired immune systems who had received two doses of the Pfizer vaccine could get a booster shot, with a decision pending on wider distribution - inspite of US and UK not giving the nod.

Pfizer: 'Third jab needed'

Pfizer is currently seeking emergency use authorization by US Food and Drug Administration (FDA) for a COVID-19 booster dose in August, said the company in a statement. Based on data from a recent study, Pfizer said that its vaccine showed strong neutralization against the Delta variant after two doses. It anticipates that the antibodies will be higher after a third dose and are performing clinical trials to determine the same. Hours later, the US govt bodies - FDA, CDC, and NIH (the National Institutes of Health) issued a joint statement saying that "Americans who have been fully vaccinated do not need a booster shot at this time".

Pfizer & Moderna vaccine 91% effective

In July, a US study revealed that Pfizer and Moderna vaccines are 91% effective in fighting against the COVID-19 virus. 91% effectiveness will be seen after two weeks of the second jab.  The result stated that only 5 %(204) participants have tested positive for SARS-CoV-2, out of which, 156 were not vaccinated, 32 had indeterminate vaccine status and 16 were completely or partially vaccinated. The presence of fever was reduced by 58% in those who still got infected and the need for bed during sickness was reduced by 60% only.  From around nine to three days, the detection of the virus was decreased by 70%. Also, the virus becomes very less transmissible to others, after getting fully or partially vaccinated with Pfizer or Moderna. 

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