CDC study | Vaccination could reduce the risk of getting infected

Adequate vaccination against COVID-19 could significantly reduce the risk of being infected, and therefore of transmitting the disease, according to a new American study. This confirms that residence workers should be vaccinated, according to a Quebec expert.

The study followed more than 1.2 million veterans’ hospice residents each week between October and early January. Those who were not adequately vaccinated were 30% to 50% more likely to be diagnosed with COVID-19.

“I think this is important evidence, which adds to other evidence,” says Benoît Mâsse, epidemiologist from the University of Montreal. “It’s not perfect, because it’s an observational study. But I think it shows that it is preferable that the staff of residences and CHSLDs be adequately vaccinated. »

The study, released Friday by the US government’s Centers for Disease Control (CDC), also warns that confounding factors could explain these results. People who are not adequately vaccinated could be more vulnerable, in particular. Adequate vaccination was defined as a two-dose basic vaccination, with a bivalent booster dose, or a booster dose every two months.

“It’s very difficult to prove that a vaccine will protect against infection,” says Mâsse. It may also be that if the cases are less severe, there is less retransmission. We know that with HIV, if the patient’s viral load is reduced, he is less likely to transmit the virus. »

These results bring grist to the mill for those who think that it is not reasonable to continue to vaccinate the entire population twice a year, according to Mr. Mâsse. “We could continue with vulnerable people, the elderly, people in residences and residence employees. And the intergenerational houses? “Yes, it is certain that if you have teenagers and elderly people in the same house, vaccination is also indicated. »