(WASHINGTON) — The United States is facing a COVID-19 surge this summer as the more contagious delta variant spreads. More than 637,000 Americans have died from COVID-19 while over 4.5 million people have died from the disease worldwide, according to real-time data compiled by the Center for Systems Science and Engineering at Johns Hopkins University.

Just 61.2% of Americans ages 12 and up are fully vaccinated against COVID-19, according to data from the Centers for Disease Control and Prevention.

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Aug 30, 11:48 am

Vaccine effectiveness against hospitalization drops, CDC says

The COVID-19 vaccines’ ability to keep people out of the hospital appears to be dropping slightly, particularly for those 75 and older, the Centers for Disease Control and Prevention announced Monday during an advisory panel.

The CDC has previously estimated that 97% of people in the hospital being treated for COVID-19 are unvaccinated, but that data was collected before the spread of delta, a hyper-transmissible variant that many doctors have warned appears to be making people sicker.

The latest CDC analysis estimates that the ability of the COVID vaccines to keep a person out of the hospital is now between 75% to 95%.

For people older than 75 in particular, vaccine effectiveness against hospitalization experienced the steepest decline, from more than 90% to 80% between June and July.

Health experts are also concerned that a person’s immunity could be waning over time, particularly among older people whose bodies are less likely than younger people to develop a strong immune response to the vaccines.

However, the vaccine still remains highly effective at preventing serious illness, according to the briefing.

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