Vaccines ward off severe Covid in the US, slowing down against infections

Covid-19 vaccines remain extremely effective in keeping people alive and out Hospital, but new US data adds further support to the argument that the shots do not prevent infections as much as they once did.

Unvaccinated people were about five times more likely to test positive for the virus than unvaccinated people in the week starting September 26, down from about 15 times less likely in May, according to the latest age-adjusted data from the Centers for Disease Control and Prevention, which was updated Monday.

The new figures come shortly after the CDC approved booster shots for all adults and may provide additional support for third doses as the United States enters its traditional winter virus season. Covid-19 cases are on the rise in many parts of the United States, including the Midwest and Northeast.

CDC data are not currently adjusted since vaccination. This means that the earliest recipients of the vaccine – mostly senior citizens and those with pre-existing conditions – may be at even greater risk.

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