CDC COVID-19 Response Team and colleagues

Mark Thompson of the CDC COVID-19 Response Team and colleagues also demonstrated that the vaccines were highly efficient at lowering the viral load, febrile symptoms, and the duration of illness in people who acquired breakthrough infections despite being vaccinated.

Health experts say that at least 70 percent of the country needs to be vaccinated

Health experts say that at least 70 percent of the country needs to be vaccinated to ensure herd immunity and completely eradicate the epidemic that killed more than 300,000 Americans.