The big questions looming in the debate about COVID-19 vaccine booster shots are who will need them and when. Maryland health officials plan to do some investigating.
They are planning to draw blood soon from 500 seniors in nursing homes in an effort to “check on their immunity levels,” according to Charles Gischlar, a spokesman for the Maryland Department of Health.
Officials declined to offer more details about the program, which Republican Gov. Larry Hogan first mentioned during a recent news conference announcing vaccine mandates for nursing home and hospital workers. He brought it up again on “CBS This Morning” last week while calling on federal regulators to OK booster shots, and said immunity begins to wane in seniors after five or six months.
State documents outlining the pilot program provided to The Baltimore Sun show the yearlong, $842,600 emergency contract with LabCorp to look at antibody levels has only just launched.
Nonetheless, two top coronavirus experts say such a study could offer some important information.
“This certainly gives you an idea of how much antibody they have in their body at any one time,” said Matthew Frieman, a longtime coronavirus researcher in the University of Maryland School of Medicine’s Department of Microbiology and Immunology. He said that “does correlate with protection.”
Frieman is not involved in the study and couldn’t say how the program would work or how the results would be applied. But he said researchers could compare antibodies found in Maryland seniors’ blood with LabCorp’s vast stock of COVID-positive samples to determine the level of antibodies likely sufficient to prevent infection. Samples also could be compared with antibody levels in hospital patients to show levels likely needed to prevent severe disease.
Antibodies are proteins that the body produces after vaccination or infection that recognize and help fight off the same invader later. There are a variety of antibody studies ongoing around the country, including by vaccine makers that have been submitting data to the U.S. Food and Drug Administration in support of boosters for all, possibly eight months after someone’s last shot.
Frieman said there is scientific consensus that more antibodies are more protective but that antibodies, and thus immunity, will wane over time. The rise of the coronavirus’ delta variant has further reduced the ability of the vaccines to stave off disease: A study by the U.S. Centers for Disease Control and Prevention released this week found vaccine effectiveness at preventing disease in front-line heath care workers dropped to 66% from 91%.
“What we don’t know is how much antibody is required to protect you from infection, or being in the hospital or dying from the virus,” Frieman said. “The general consensus from studies published is you don’t need high [level] of antibody to protect you from severe disease, but you probably do need [a] high level to keep from being infected in the first place, especially from the delta variant.”
It’s worth looking at seniors specifically, but it remains to be seen how much the Maryland study will contribute to answering such questions, said Andrew Pekosz, professor of molecular microbiology and immunology in the Johns Hopkins University Bloomberg School of Public Health.
The COVID experts said they already know seniors appear to produce lower levels of antibodies after vaccination and lose them faster.
A key question is whether the study reveals anything about the seniors’ levels of so-called neutralizing antibodies, which requires a special kind of testing to measure. The state has not said what kinds of tests the study will use. People produce all kinds of antibodies, which recognize different parts of the virus, but neutralizing antibodies are the real defenders against COVID-19. Pekosz said researchers can assume they are getting neutralizing antibodies, but may not know how many.
The FDA recently authorized a third shot for those who are immunocompromised, such as cancer patients, those who’ve had a transplant or with advanced HIV, because the first set of vaccinations never produced much of these essential antibodies for such people. Hogan, a cancer survivor, revealed he already has been given a third dose on his doctor’s advice.
Hogan also has called on the FDA to speed up approvals for boosters generally, along with full approvals for vaccines for all ages. Democratic President Joe Biden also has said he supports booster shots.
But many in public health maintain that getting unvaccinated people a first dose should be the priority to work toward ending the pandemic. Careful consideration, they say, should be given to who gets booster shots.
The FDA — and Pekosz and Frieman — maintain the vaccines are doing a good job still at preventing hospitalizations and deaths from the more contagious delta variant. Rising reports of “breakthrough cases” in vaccinated people aren’t correlating with a rise in hospitalizations among those cases.
Pekosz said federal and state officials ought not “raise the bar too much. Keeping people out of [the] hospital is most important.”
Pekosz said the elderly already appear more likely to suffer more severe breakthrough cases, and the delta variant could make matters worse — making the case for more information specifically about seniors.
“I like the emphasis on seniors, but this vulnerability is something already shown; we mostly already know the answer to what Maryland appears to be asking,” he said. “But there is benefit to this, absolutely. Given the increased disease potential, it’s not a bad idea to make sure we oversample certain populations to make sure we have a good understanding.”
The FDA continues to consider boosters starting with those who were first vaccinated, including health care workers and seniors, and is expected to make a determination soon.
The Maryland study is just getting underway, according to a summary of the program included in the LabCorp contract submitted to the state’s Board of Public Works, which is scheduled to consider the emergency procurement during its Wednesday meeting. There was no competitive bidding for the contract.
The first 500 samples are expected to be taken over two weeks in late August, the summary says. Three rounds of tests could occur over the year, suggesting antibody samples could be taken before and after seniors are given booster shots, if they are authorized more broadly by the FDA in coming weeks or months. A maximum of 20,000 tests will be conducted “to assess antibody levels in other nursing facilities and congregate care type settings for potentially vulnerable populations.”
State data shows more than 90% of those age 65 and older in Maryland have received at least one dose of COVID-19 vaccine. There have been more than 33,600 COVID cases in the state’s nursing facilities and 3,560 deaths.
Joe DeMattos, president and CEO of the Health Facilities Association of Maryland, said up to a quarter of nursing home residents and patients also are immunocompromised and already qualify for a third shot. Adding other seniors seems like a good idea, he said.
“We think in coming days and weeks it will be critical public policy that President Biden prioritize coronavirus boosters for people in nursing homes and hospitals,” DeMattos said.