The majority of US people, including the vast majority of its elders, are approaching the holiday season and an anticipated increase in instances of the virus without having received the full complement of vaccine protection.

Only 16% of people aged 18 and older and 36% of seniors in the United States have received the new booster shot, which became available in September.

Even those who have been immunized but haven't had a shot in a while may not be adequately protected against major infections because the vaccines' potency degrades with time.

The immunizations are effective, according to every piece of information that has surfaced in the last two years. The issue is twofold: not getting your last dose for a while causes the effectiveness to wane and the effectiveness changes as the virus develops.

The lesson is that vaccinations are effective and having a booster injection is crucial, especially for older, more vulnerable people, and people who haven't had a shot in a while are at far higher risk than those who have.

The #US is not helping its case with the accusations being raised about its #biolabs; this time, a university in #Boston created a new lethal #COVID variant with an 80% mortality rate. pic.twitter.com/Fwk2ZAVGvJ

— Al Mayadeen English (@MayadeenEnglish) October 23, 2022

Although it lasts longer than protection against contracting the virus, the vaccinations' effectiveness against serious illness and death nevertheless deteriorates rapidly.

Hospitalizations for COVID are currently on the rise, especially in seniors, which is at least in part due to the poor uptake of booster doses.

The effectiveness of the revised booster doses, which are directed against both the original viral strain and the Omicron version, has been quantified by recent CDC data.

The usefulness of the shots in preventing hospitalization was reported in conflicting ways by two studies that were published earlier this month. When compared to receiving no vaccine, one study revealed that the revised dose was 57% effective against hospitalization.

The revised injection was 38% more successful at preventing hospitalization compared to receiving the last dosage five to seven months earlier, the study revealed; however, if the last dose was received 11 months ago or more, the updated shot was 45% more effective.

Higher effectiveness among elderly 

The second study found higher effectiveness among adults 65 and older. Compared to unvaccinated people, the updated vaccine was 84% effective against hospitalization.

Compared to people who had received two or more doses of the original shot only, the updated one was 73% effective.

Relative vaccine effectiveness is impacted by the fact that so many Americans — including unvaccinated people — have already been infected by COVID, meaning that they may have some natural immunity.

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The shots are much less effective at preventing routine infections, and some scientists say the boosters' value may be more limited in younger populations who generally aren't at risk of severe cases anyways.

“There’s a world of difference in what's happening to younger healthy people and what’s happening to older, sicker people," said Cornell virologist John Moore. "If you’re in a vulnerable population, it absolutely makes sense to be up to date with your boosters."

Americans don't think they need the updated shots

In a recent KFF poll, over two-thirds of respondents who were Republicans or leaning Republican and who had not received an updated booster shot stated they did not think they needed it. Another 37% said they didn't think the benefit was worth it.

According to a recent report from the UK Health Security Agency that concentrated on older Omicron variants, protection against hospitalization and mortality had decreased to about 50% compared to unvaccinated people six to eight months after receiving a second dose of the Pfizer or Moderna vaccine.

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For the first three months following the shot, the effectiveness was between 80% and 90%.

A third dose of either vaccination was marginally more effective in preventing hospitalization in those who had received it, with a nine-month efficacy rate of roughly 60%.

Even after the revised boosters were introduced, the virus continued to develop, and it is still possible that new strains would emerge that will be even more resistant to the vaccinations' protection.