Almost all of the COVID-19 deaths in the US are among those who are unvaccinated, an Associated Press analysis found.

While over 853,000 were hospitalized for COVID-19 in May, less than 1,200 of them or about 0.1 percent were people who were fully vaccinated, the AP found using data from the Centers for Disease Control and Prevention.

Of the 18,000 COVID-19 deaths, only 150 were people who were fully vaccinated or only 0.8 percent.

"They are [vaccines] nearly 100 percent effective against severe disease and death, meaning nearly every death due to COVID-19 is particularly tragic because nearly every death, especially among adults, due to COVID-19 is, at this point, entirely preventable," CDC Director Dr. Rochelle Walensky said during a press briefing on Tuesday.

More than 45 percent of all Americans are fully vaccinated against, CDC data shows, but The Washington Post reported vaccination rates have been on the decline, with fewer Americans signing up to get the shot.

This comes at a time when top health officials are urging Americans to get vaccinated as the more transmissible Delta variant - which originated in India - becomes a growing concern. It may also be able to evade protection from existing vaccines, as Insider's Aria Bendix reported.

Walensky told NBC News that data so far shows that two doses of Pfizer and Moderna vaccines should work really well against the Delta variant, and she is encouraging people to get their second doses if they haven't.

She is however concerned about pockets across the country that are less vaccinated than others. There's a stark vaccine rate disparity amongst counties across the US with some at only 0.1 percent and others near 100 percent.

Those that have lower vaccine rates are at a higher risk of an outbreak as a result of the variant. Experts told Insider's Aria Bendix and Joanna Lin Su that they ideally want a community to have at least a 75 percent vaccination rate so the virus is less able to pass from person to person.

"Some places are above 60 percent, so there are some pockets that are pretty protected," Lisa Lee, an epidemiologist at Virginia Tech, recently told Insider.

"We have to understand, though, that it just takes a couple of cases, a couple of people coming into a community, to pass this along."

This article was originally published by Business Insider.

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