Study Confirms Vaccines Sharply Cut COVID-19 Infection Risk

A new study by researchers at the Centres for Disease Control has revealed that a full vaccination reduces the risk of COVID-19 infection by roughly 90 percent.

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The trial was conducted on United States nurses, firefighters, and other front-line workers who received an mRNA-based COVID-19 vaccine.

The study, published on April 2 in the Morbidity and Mortality Weekly Report of the CDC, further confirmed that the COVID-19 vaccine is very effective in reducing the risk of infection.

According to the report, the clinical trials showed that the mRNA-based vaccines manufactured by Moderna and Pfizer–BioNTech are highly effective at protecting people from illness caused by SARS-CoV-2.

To learn whether the vaccines also shield people from becoming infected in the first place, Mark Thompson at the US Centers for Disease Control and Prevention in Atlanta, Georgia, and his colleagues studied SARS-CoV-2 test results from nearly 4,000 people whose work puts them at high risk of infection

Study participants were then vaccinated between mid-December 2020 and mid-March 2021. After vaccination, they swabbed their own noses for viral testing once a week for 13 weeks.

Participants were considered fully immunised two weeks after receiving their second dose of vaccine.

The findings indicated that full immunisation was 90 percent effective at protecting people against infection, and a single dose was 80 percent effective.

But the researchers caution that because very few participants became infected after vaccination, it’s difficult to state the vaccines’ effectiveness against infection with high precision.

“These findings indicate that authorised mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions. COVID-19 vaccination is recommended for all eligible persons.

“Authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection in real-world conditions.

“These interim vaccine effectiveness findings for both Pfizer-BioNTech’s and Moderna’s mRNA vaccines in real-world conditions complement and expand upon the vaccine effectiveness estimates from other recent studies and demonstrate that current vaccination efforts are resulting in substantial preventive benefits among working-age adults.

“They reinforce CDC’s recommendation of full 2-dose immunisation with mRNA vaccines,” the researchers said.