For practically a month, the Centers for Disease Control and Prevention’s on-line vaccine tracker has proven that nearly everybody 65 and older within the U.S. — 99.9 p.c — has acquired a minimum of one Covid-19 vaccine dose.
That could be outstanding — if it had been true.
But well being consultants and state officers say it’s actually not.
They observe that the CDC as of Sunday had recorded extra seniors as having been a minimum of partly vaccinated — 55.4 million — than there are individuals within the age group — 54.1 million — in response to the most recent census information from 2019. The CDC’s vaccination charge for residents 65 and older can be considerably larger than the 89 p.c vaccination charge present in a ballot carried out in November by KFF. Similarly, a YouGov ballot carried out final month for The Economist discovered that 83 p.c of individuals 65 and up mentioned that they had acquired a minimum of an preliminary dose of a vaccine.
And the CDC counts 21 states as having virtually all their senior residents a minimum of partly vaccinated (99.9 p.c). But a number of of these states present a lot decrease figures of their vaccination databases, together with California, at 86 p.c, and West Virginia, at practically 90 p.c as of Monday.
The questionable CDC information on seniors’ vaccination charges illustrates one of many potential issues well being consultants have flagged in regards to the CDC’s Covid vaccination information.
Knowing with accuracy what quantity of the inhabitants has rolled up sleeves for Covid photographs is significant to public well being efforts, mentioned Dr. Howard Forman, a professor of public well being at Yale University School of Medicine.
“These numbers matter,” he mentioned, notably in efforts to extend the charges of booster doses which have been administered. As of Sunday, about 47 p.c of individuals 65 and older had acquired booster photographs because the federal authorities made them out there in September.
“I’m not sure how reliable the CDC numbers are,” Forman mentioned, pointing to the discrepancy between state information and the company’s 99.9 p.c determine for seniors, which he mentioned can’t be appropriate.
“You want to know the best data to plan and prepare and know where to put resources in place — particularly in places that are grossly undervaccinated,” he mentioned.
Getting an correct determine on the proportion of residents who’ve been vaccinated is tough for a number of causes. The CDC and states could also be utilizing completely different inhabitants estimates. State information could not account for residents who get vaccinated in states aside from the place they stay or in clinics in federal services, resembling prisons, or these managed by the Veterans Health Administration or the Indian Health Service.
CDC officers mentioned the company could not have the ability to decide whether or not persons are getting their first, second or booster doses in the event that they bought their photographs in numerous states and even from suppliers in the identical metropolis or state. That can lead the CDC to overestimate first doses and underestimate booster doses, CDC spokesperson Scott Pauley mentioned.
In a footnote on its Covid vaccination information tracker webpage, the CDC says: “There are challenges in linking doses when someone is vaccinated in different jurisdictions or at different providers because of the need to remove personally identifiable information (de-identify) data to protect people’s privacy. This means that, even with the high-quality data CDC receives from jurisdictions and federal entities, there are limits to how CDC can analyze those data.”
On its dashboard, the CDC has capped the share of the inhabitants that has acquired a vaccine at 99.9 p.c. But Pauley mentioned the figures could possibly be off for a number of causes, resembling potential data-reporting errors or the census denominator’s not together with everybody who lives in a selected county, like part-time residents.
Liz Hamel, the vp and director of public opinion and survey analysis at KFF, agrees that it’s extremely unlikely that 99.9 p.c of seniors have been vaccinated. She mentioned the variations between CDC vaccination charges and people present in KFF and different polls are vital. “The truth may be somewhere in between,” she mentioned.
Hamel famous that the KFF vaccination charges tracked carefully with the CDC’s figures within the spring and summer season however started diverging within the fall, simply as booster photographs grew to become out there. KFF surveys present that the share of adults who had been a minimum of partly vaccinated modified little from September to November, transferring from 72 p.c to 73 p.c. But CDC information present a rise from 75 p.c in September to 81 p.c in mid-November.
The penalties of circumstances will more and more be decided by the proportion of unvaccinated and unboosted, so having deal with on that is important for understanding the pandemic.
Epidemiologist William Hanage, Harvard University
As of Sunday, the CDC says, 83.4 p.c of adults had been a minimum of partly vaccinated.
William Hanage, an affiliate professor of epidemiology at Harvard University, mentioned such discrepancies name the CDC determine into query. He mentioned getting an correct determine on the share of seniors who’ve been vaccinated is necessary as a result of the age group is most susceptible to extreme penalties of Covid, together with loss of life.
“It is important to get them right because of the much-talked-about shift from worrying about cases to worrying about severe outcomes like hospitalizations,” Hanage mentioned. “The consequences of cases will increasingly be determined by the proportion of unvaccinated and unboosted, so having a good handle on this is vital for understanding the pandemic.”
For instance, CDC information present that New Hampshire leads the nation in vaccination charges, with about 88 p.c of its inhabitants having been a minimum of partly vaccinated. The New Hampshire vaccination dashboard reveals that 61.1 p.c of residents have been a minimum of partly vaccinated, however the state isn’t counting all individuals who get their photographs in pharmacies due to information assortment points, mentioned Jake Leon, a spokesperson for the state Department of Health and Human Services.
In addition, Pennsylvania well being officers say they’ve been working with the CDC to appropriate vaccination charge figures on the federal web site. The state is making an attempt to take away duplicate vaccination information to verify the dose classification is appropriate — from preliminary doses via boosters — mentioned Mark O’Neil, a spokesperson for the state Health Department.
As a part of the trouble, the CDC late final month lowered the reported proportion of adults within the state who had acquired a minimum of one dose from 98.9 p.c to 94.6 p.c. It additionally lowered the share of seniors who’ve been absolutely vaccinated from 92.5 p.c to 84 p.c.
However, the CDC hasn’t modified its determine for the proportion of seniors who’ve been partly vaccinated. It stays at 99.9 p.c. The CDC dashboard says that, as of Sunday, 3.1 million seniors in Pennsylvania had been a minimum of partly vaccinated. The newest census information present that Pennsylvania has 2.4 million individuals 65 and older.