The pace of people getting Covid-19 vaccine booster shots in the United States has dropped to the lowest it has ever been, and many public health experts are concerned.
As of Monday, about 64% of the US population is fully vaccinated against Covid-19 with at least their initial two-dose series, and 28% have received a booster shot. But the pace of booster doses going into arms is the lowest it has been in months – since the US Centers for Disease Control and Prevention first recommended boosters for seniors and other at-risk adults in September, according to a CNN analysis of CDC data. The agency expanded its recommendation for booster doses in November to include all adults.
People who received the Johnson & Johnson vaccine as their first dose seem less likely to get their booster than other vaccinated groups. Among those eligible for a booster, less than one-third who initially received the Johnson & Johnson shot have been boosted, compared with about half of those who completed their initial two-dose series of Moderna, at 52%, or Pfizer, at 47%, according to CNN’s analysis.
Among people who are vaccinated but not boosted, about 4 in 10 – or 39% – say they want to get a booster as soon as they can, but another 4 in 10 say they either will definitely not get a booster or will do so only if required, according to a Kaiser Family Foundation survey released last month.
The survey found that intent to get boosted was split along party lines, with 58% of Democrats who are vaccinated but not boosted saying they want to get a booster dose as soon as they can, compared with just 18% of Republicans who have not gotten a booster.
The survey was conducted among a nationally representative sample of about 1,500 adults from January 11 through January 23, during a period when the Omicron coronavirus variant was predominant and the US had a record surge in cases and hospitalizations.
“I think people have Covid fatigue; even if you’ve gotten vaccinated and you haven’t gotten really sick, people feel protected,” Dr. Georges Benjamin, executive director of the American Public Health Association, told CNN.
Benjamin said he is not surprised by the slow uptake of coronavirus vaccine booster doses, as there has been a long history of lagging adherence to other recommended vaccines and medications when it comes to public health in the United States.
“It comes as no surprise to me when you think about the fact that when we start a new vaccination program, there’s always been very, very slow uptake,” Benjamin said. “The amount of people that have gotten fully vaccinated – the over 200 million who have got vaccinated already – that’s a remarkable number. So we should recognize that that’s remarkable. Now, we also ought to say that in light of the seriousness of the problem, we haven’t done nearly enough.”
‘It seems like people consider it something extra’
The slow uptake of coronavirus vaccine booster doses has been “a bit of a mystery” to Andy Pekosz, professor at the Johns Hopkins Bloomberg School of Public Health, he said, especially since boosters appear to improve protection against emerging variants such as Omicron.
“When Omicron came through, it became very clear that a booster was a tremendous help in terms of keeping people out of the hospital, and you would think that people who have done the first set of vaccines would be the ones who would be more than willing to line up for a third one that would get them much better immunity,” Pekosz told CNN.
“It seems like people consider it something extra or something optional, as opposed to, it really is almost critical when it comes to Omicron infections,” he said.
Most adults who are vaccinated but not boosted, 60%, say that news of Omicron’s spread has not made much of a difference as to whether they will get a booster. However, about 3 in 10 – or 29% – say the spread of Omicron has made them more likely to get a booster shot, according to the KFF survey released last month.
Boosters will be key as the nation makes an effort to boost Covid-19 immunity across communities, Pekosz said, an effort that could help push the coronavirus to an endemic disease instead of causing pandemic-levels of infection. Endemic means a disease has a constant presence in a population but is not affecting an alarmingly large number of people, as typically seen in a pandemic.
“Booster is the easy way to strong immunity now, and so we’d like to see more people taking that easy way to strong immunity. I would like to see a much higher booster rate,” Pekosz said. He added that it remains unclear how close the United States is to the level of protection needed to end the pandemic because it is difficult to track immunity caused by natural infections.
Overall, the protection against Covid-19 that three doses of vaccine provides, compared with just two doses, is obvious to Dr. Saju Mathew, an Atlanta-based primary care physician who has been treating patients throughout the pandemic.
“I can definitely tell you, there is a difference between my patients who are vaccinated versus my patients who are boosted if they get a breakthrough infection. So if they get a breakthrough case, most of my patients that are boosted are doing much better at home,” Mathew told CNN.
“It’s like clockwork. When I see them, I’ll ask, ‘Are you boosted?’ If they say they’re not boosted, I can already predict that they’re going to tell me their symptoms are much worse,” Mathew said. “But if you’re boosted, most patients are doing well and staying out of the hospital because, I would argue, they are boosted.”
Looking at the metrics
Even if the majority of a community is fully vaccinated with two doses, that would not offer nearly as much protection as if the majority were boosted with three doses, Mathew said, adding that he is very concerned about how few people in the United States are boosted right now.
Because of this, as more states examine their vaccination rates while deciding to roll back mask mandates and other Covid-19 mitigation measures, Mathew said, they should take into consideration how much of their population is boosted against Covid-19.
“If I was governor, I think that would make a huge difference,” he said. “The metrics would be more accurate.”
Many states – including California, Connecticut, Delaware, Illinois, Maryland, Massachusetts, Nevada, New Jersey, New York, Oregon and Rhode Island – have lifted or made plans to lift indoor or school mask mandates based on declining Covid-19 case counts, declining hospitalizations and increasing vaccination rates.
“Hospitalizations and ICU admissions are key for metrics in addition to vaccination rates. But let’s remember, 61% is fully vaccinated in the US, but only 25% is boosted,” Mathew said. “If you’re not boosted, your vaccine works only 57%, compared to 90% if you’re boosted.”
Booster doses of the Pfizer/BioNTech and Moderna coronavirus vaccines are safe, and they offer high levels of protection against severe Covid-19 even though that protection can wane over time, according to two studies published by the CDC on Friday.
Evidence of waning protection “reinforces the importance of further consideration of additional doses to sustain or improve protection” against Covid-19-linked hospitalizations and emergency department visits, one of the studies says.
That study suggests that, with the Omicron variant dominant in the United States, vaccine effectiveness was 87% against Covid-19 emergency department or urgent care visits and 91% against hospitalizations in the two months after a third dose. Protection fell to 66% and 78%, respectively, by the fourth month, the data showed.
But in comparison, after just two doses of coronavirus vaccine, when the Omicron variant was predominant, vaccine effectiveness against hospitalizations declined from 71% in the two months after vaccination to 54% by at least five months, the study found.
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The data is still early, but the studies offer more evidence that booster doses of coronavirus vaccine can significantly increase protection against Covid-19 in the short term and that protection seems to wane over time, said Benjamin, of the American Public Health Association.
He added that he would like to see more data specifically on the vaccine effectiveness of booster doses in older adults, people with chronic diseases and people who are immunocompromised, compared with younger people or health adults.
“Only time will tell exactly how durable it is in the various populations, based on age and degree of underlying diseases,” Benjamin said. “But the fact that, at least so far, it still protects people from getting really sick and dying tells me that it’s still very effective.”
CNN’s Deidre McPhillips contributed to this report.