Colorado has enough COVID-19 vaccine doses to start giving booster shots to people with compromised immune systems due to an organ transplant, recent cancer treatment or other high-risk conditions as defined by the Centers for Disease Control and Prevention.
The Colorado Department of Public Health and Environment said Friday that it will follow the CDC’s recommendations, and that people who say that they have a qualifying condition won’t be required to provide proof before receiving a third dose.
The U.S. Food and Drug Administration amended its authorization for the two-dose Pfizer and Moderna vaccines late Thursday to allow third shots for people with compromised immune systems. On Friday, CDC Director Rochelle Walensky approved an advisory committee’s recommendation to begin offering boosters for the roughly 7 million people who qualify.
Colorado’s state health department encouraged clinics to begin reaching out to patients who they know have conditions that would qualify them for a booster, and is working with local health departments to begin offering third shots in long-term care facilities.
The CDC said people who qualify for a third dose include those who:
- Had an organ transplant at any time, or a recent stem cell transplant
- Were recently treated for cancer
- Were born with a compromised immune system
- Have uncontrolled HIV
- Are being treated with high doses of immune-suppressing drugs
- Have another condition that can affect the immune system, like chronic kidney disease
Currently, the recommendations don’t include people with other conditions that raise their risk of severe COVID-19, like heart disease, diabetes or advanced age.
The recommendation only applies to people who received the Pfizer or Moderna shots, though studies are ongoing about the best course for people who received the single-dose Johnson & Johnson vaccine. So far, small studies haven’t found an increased risk of severe side effects from mixing vaccine types, but it’s possible rarer reactions could be found as larger groups of people try them, according to an article in Nature.
Thousands of people in Colorado, however, already have received third doses.
State health department spokeswoman Jessica Bralish said the state’s immunization record system shows 7,164 people, or about 0.2% of those who have received any COVID-19 vaccine doses in Colorado, got a third shot before it was approved. The CDC estimated about 1.1 million people nationwide got a third shot before they were allowed. It isn’t clear how many of those people would now qualify.
The third shots will be free, like all vaccines against COVID-19. The Moderna shot is available for adults, while children 12 and over who have compromised immune systems could get a third dose of the Pfizer shot. CDC officials emphasized that people with compromised immune systems should continue wearing masks and practicing social distancing even after a third shot.
It’s clear that people who have had a transplant remain at an elevated risk even after two doses, said Dr. Dorry Segev, a professor of surgery and epidemiology at Johns Hopkins University who is studying booster shots in those patients. About half of transplant patients don’t generate any antibodies after two doses, and those that do have lower-than-average levels, he said.
The odds of getting a breakthrough infection severe enough to result in hospitalization are about 400 times higher for a person who has had a transplant than for someone who hasn’t, Segev said. People whose immune systems are compromised for other reasons also have higher risks, though it varies depending on their condition and the medications they take, he said.
Dr. Balazs Halmos, a professor of medicine at Montefiore Medical Center in New York City, said the data is limited, but suggests anywhere from 20% to 40% of patients with compromised immune systems who didn’t have antibodies after two shots develop them after a third shot. More work needs to be done on how best to help those who don’t respond to a booster, he said.
Halmos said he expects discussions to continue about whether boosters make sense for other people who may not have a strong immune response, such as the very old. It’s possible health care workers could also be offered a third shot in the future, since they have the highest risk of exposure, he said.
Earlier this week, the World Health Organization urged caution in countries considering boosters, arguing that the standard of proof that a third dose is beneficial should be high when people in much of the world can’t get a first shot. In much of Africa and parts of the Middle East and Central Asia, less than 5% of the population has had even a single dose of the vaccine, leaving their higher-risk people largely exposed to new surges.
Several members of the CDC advisory panel raised a similar concern despite voting to recommend extra doses, according to The Washington Post. When the virus is spreading widely among unvaccinated populations, it has more opportunities to mutate into forms that are more contagious or better at evading the immune system.
“We are all very worried about the delta variant, but that may be the least of our problems if COVID-19 continues to circulate across the U.S. and the world,” said Helen Keipp Talbot, an infectious diseases doctor at Vanderbilt University. “And so I think it’s incredibly important that we remember that we need to begin sharing more and more vaccines across the world.”