The Centers for Disease Control and Prevention has joined the Food and Drug Administration in backing an extra COVID-19 vaccine dose for people with severely weakened immune systems.
CDC Director Rochelle Walensky put out a statement Friday afternoon saying that she signed the advisory panel’s recommendation and called it “an important step in ensuring everyone, including those most vulnerable to COVID-19, can get as much protection as possible from COVID-19 vaccination.
The CDC cites emerging data that shows fully vaccinated immunocompromised people have accounted for an outsized percentage of breakthrough cases (40-44%) and are more vulnerable to serious, prolonged illness.
Immunocompromised people are about 3 percent of the U.S. adult population, according to the CDC, and include recipients of organ or stem cell transplants, people suffering from advanced HIV infections, people being treated for cancer, people who have to take medicine that weakens the immune system, and others. A full list of conditions can be found on CDC’s website.
The CDC recommends that the extra dose be of the same series taken before and it should be administered at least four weeks after becoming fully vaccinated.
The Food and Drug Administration ruled Thursday night that transplant recipients and other similarly immune-compromised patients can get a third dose of either the Pfizer or Moderna vaccine. But the decision offers an extra dose only to those high-risk groups — not the general public.
These patients have been clamoring for months for better protection, some of them traveling across state lines or lying to get another dose. About 1.1 million people already have gotten at least a third dose of the Pfizer or Moderna vaccines on their own, the Centers for Disease Control and Prevention revealed Friday — although it’s not clear how many did so because they had weakened immune systems.
Here are some things to know:
WHY DO SOME PEOPLE NEED AN EXTRA DOSE?
The Pfizer and Moderna vaccines offer powerful protection for otherwise healthy people, but many who take immune-suppressing medications or have diseases that tamp down their immune systems generally get less benefit from the standard two doses.
Those hospitalized patients “did all the right things — they’re just suffering from a lack of good vaccine protection,” said Dr. Camille Kotton of Massachusetts General Hospital, one of CDC’s advisers.
Roughly 7 million American adults are classified as immune-compromised, but the FDA singled out transplant recipients and others with similar levels of immune suppression. The FDA didn’t spell out exactly who falls into those other categories. But according to the CDC, people with blood cancers, those taking certain chemotherapies, and those taking certain medications such as rituximab for rheumatoid arthritis tend to have especially poor responses to vaccination.
WILL I NEED A DOCTOR’S NOTE OR A BLOOD TEST?
The FDA didn’t require either. Some experts have said there should be no barriers to getting a third dose. “We would want to make that as easy as possible,” said Dr. William Schaffner, an infectious diseases expert at Vanderbilt University.
WHAT WILL A THIRD DOSE COST?
Shots given under FDA’s emergency use authorization are free.
IS MIX-AND-MATCH ALLOWED?
The government encourages the third dose to be the same as the first two, but doesn’t mandate it.
HOW WELL DOES A THIRD DOSE WORK?
It helps at least some people. This week Canadian researchers reported 55% of transplant recipients given a third dose two months after standard vaccination had good antibody levels compared to 18% who were given a dummy third shot for comparison. Health experts urged these high-risk patients to continue masking and taking other precautions since there’s no guarantee a third dose will work.
WHAT IF A THIRD DOSE STILL DOESN’T WORK?
It’s not a substitute for vaccination, but the FDA has authorized an antibody treatment as a preventive treatment if high-risk patients are exposed to the virus. And it’s critical for family members and others close to fragile patients to be vaccinated to protect them from exposure.
More research is underway to better tease out whether some immune-compromised patients need still other options, such as carefully monitored changes to their medications.
WHAT IF I HAD THE SINGLE-DOSE JOHNSON & JOHNSON VACCINE?
There’s little data on how another dose works in high-risk people who received that vaccine, although it’s likely a small number considering fewer than 14 million Americans overall have received the J&J shot. Still, CDC counts at least 90,000 who have gotten another dose on their own.
FDA vaccines chief Dr. Peter Marks said the agency is working to get more information about immune-suppressed J&J patients but for now, the evidence only backs a recommendation of extra doses are for Pfizer and Moderna recipients with fragile immune systems.
IS THIS A BOOSTER?
Not really, because boosters are for people whose immunity wanes over time and these high-risk groups didn’t get enough protection to begin with. They now will qualify for a third dose at least 28 days after their second shot — making a third dose part of their initial prescription. That’s similar to how France has handled vaccinations for the immune-compromised since April.
WHAT ABOUT BOOSTERS FOR EVERYONE ELSE?
U.S. health authorities insist it’s not yet time for booster doses for the general population.
“We believe sooner or later you will need a booster for durability of protection” — but not yet, Dr. Anthony Fauci, the government’s top infectious diseases expert, told reporters this week.
The CDC is closely monitoring rates of COVID-19 hospitalizations and deaths, as well as long-running studies of how often vaccinated health workers experience so-called “breakthrough infections” especially with the extra-contagious delta variant. That evidence will drive any decision.