Pfizer vaccine highly effective against Covid-19 hospitalizations for 6 months: Study
“Protection against infection does decline in the months following a second dose,” Sara Tartof from Kaiser Permanente, US.Author : Divyanshi Soni
On Tuesday, a study was published by the Lancet Study, according to which two doses of the Pfizer COVID-19 vaccine are 90 percent effective against hospitalization from the disease for all variants.
The researchers have found that the efficacy of other Covid-19 vaccines has decreased from 88 percent within one month after receiving two vaccine doses to 47 percent after six months. Meanwhile, the efficacy of Pfizer remained 90 percent against hospitalization for all variants.
The study was conducted by the Kaiser Permanente Southern California (KPSC) health system between December 4, 2020, and August 8, 2021. During the study, the team of researchers analyzed 3,436,957 electronic health records, out of which 5.4 percent of people were infected with S-CoV-2. And out of 5.4 percent, 6.6 percent were hospitalized.
One of the researchers claims that the vaccines are highly effective and are responsible for controlling admission in hospitals. The study's lead author, Sara Tartof from Kaiser Permanente in the US, was quoted saying, “Our study confirms that vaccines are a critical tool for controlling the pandemic and remain highly effective in preventing severe disease and hospitalization, including from the Delta and other variants of concern.”
“Protection against infection does decline in the months following a second dose,” she continued.
Some limitations were acknowledged by the authors of the study while conducting the study. First, as the vaccinated population was randomized, so the researchers could not determine causal relationships between vaccination and COVID-19 outcomes. Second, they did not have data on adherence to mask guidelines, social interactions, occupation, and disease rates in the study population.