For almost a month, the Facilities for Illness Management and Prevention’s on-line vaccine tracker has proven that virtually everyone 65 and older in the US — 99.9% — has acquired at the very least one covid vaccine dose.

That may be outstanding — if true.

However well being specialists and state officers say it’s actually not.

They be aware that the CDC as of Dec. 5 has recorded extra seniors at the very least partly vaccinated — 55.4 million — than there are individuals in that age group — 54.1 million, in keeping with the most recent census information from 2019. The CDC’s vaccination fee for residents 65 and older can be considerably increased than the 89% vaccination fee discovered in a poll performed in November by KFF.

Equally, a YouGov poll, performed final month for The Economist, discovered 83% of individuals 65 and up stated they’d acquired at the very least an preliminary dose of vaccine.

And the CDC counts 21 states as having virtually all their senior residents at the very least partly vaccinated (99.9%). However a number of of these states present a lot decrease figures of their vaccine databases, together with California, with 86% inoculated, and West Virginia, with nearly 90% as of Dec. 6.

The questionable CDC information on seniors’ vaccination charges illustrates one of many potential issues well being specialists have flagged about CDC’s covid vaccination information.

Understanding with accuracy what quantity of the inhabitants has rolled up sleeves for a covid shot is important to public well being efforts, stated Dr. Howard Forman, a professor of public well being at Yale College Faculty of Medication.

“These numbers matter,” he stated, significantly amid efforts to extend the charges of booster doses administered. As of Dec. 5, about 47% of individuals 65 and older had acquired a booster shot for the reason that federal authorities made them accessible in September.

“I’m unsure how dependable the CDC numbers are,” he stated, pointing to the discrepancy between state information and the company’s 99.9% determine for seniors, which he stated can’t be right.

“You wish to know one of the best information to plan and put together and know the place to place sources in place — significantly in locations which are grossly undervaccinated,” Forman stated.

Getting an correct determine on the proportion of residents vaccinated is tough for a number of causes. The CDC and states could also be utilizing totally different inhabitants estimates. State information could not account for residents who get vaccinated in a state apart from the place they reside or in clinics situated in federal services, resembling prisons, or these managed by the Veterans Health Administration or Indian Health Service.

CDC officers stated the company could not have the ability to decide whether or not an individual is receiving a primary, second or booster dose if their photographs had been acquired in numerous states and even from suppliers inside the similar metropolis or state. This could trigger the CDC to overestimate first doses and underestimate booster doses, CDC spokesperson Scott Pauley stated.

“There are challenges in linking doses when somebody is vaccinated in numerous jurisdictions or at totally different suppliers due to the necessity to take away personally identifiable info (de-identify) information to guard individuals’s privateness,” in keeping with a footnote on the CDC’s covid vaccine information tracker webpage. “Which means that, even with the high-quality information CDC receives from jurisdictions and federal entities, there are limits to how CDC can analyze these information.”

On its dashboard, the CDC has capped the share of the inhabitants that has acquired vaccine at 99.9%. However Pauley stated its figures might be off for a number of causes, such because the census denominator not together with everybody who at the moment resides in a selected county, like part-time residents, or potential data-reporting errors.

Liz Hamel, vice chairman and director of public opinion and survey analysis at KFF, agrees it’s extremely unlikely 99.9% of seniors have been vaccinated. She stated the variations between CDC vaccination charges and people present in KFF and different polls are vital. “The reality could also be someplace in between,” she stated.

Hamel famous the KFF vaccination charges tracked intently with CDC’s figures within the spring and summer season however started diverging in fall, simply as booster photographs grew to become accessible.

KFF surveys present the share of adults at the very least partly vaccinated modified little from September to November, transferring from 72% to 73%. However CDC information reveals a rise from 75% in September to 81% in mid-November.

As of Dec. 5, the CDC says, 83.4% of adults had been at the very least partly vaccinated.

William Hanage, an affiliate professor of epidemiology at Harvard College, stated such discrepancies name into query that CDC determine. He stated getting an correct determine on the share of seniors vaccinated is essential as a result of that age group is most weak to extreme penalties of covid, together with demise.

“You will need to get them proper due to the much-talked-about shift from worrying about instances to worrying about extreme outcomes like hospitalizations,” Hanage stated. “The implications of instances will more and more be decided by the proportion of unvaccinated and unboosted, so having an excellent deal with on that is very important for understanding the pandemic.”

For instance, CDC information reveals New Hampshire leads the nation in vaccination charges with about 88% of its whole inhabitants at the very least partly vaccinated.

The New Hampshire vaccine dashboard reveals 61.1% of residents are at the very least partly vaccinated, however the state will not be counting all individuals who get their photographs in pharmacies attributable to information assortment points, stated Jake Leon, spokesperson for the state Division of Health and Human Companies.

As well as, Pennsylvania well being officers say they’ve been working with the CDC to right vaccination fee figures on the federal web site. The state is making an attempt to take away duplicate vaccination data to verify the dose classification is right — from preliminary doses via boosters, stated Mark O’Neil, spokesperson for the state well being division.

As a part of the trouble, in late November the CDC decreased the share of adults within the state who had at the very least one dose from 98.9% to 94.6%. It additionally lowered the share of seniors who’re totally vaccinated from 92.5% to 84%.

Nevertheless, the CDC has not modified its determine on the proportion of seniors who’re partly vaccinated. It stays 99.9%. The CDC dashboard says that 3.1 million seniors in Pennsylvania had been at the very least partly vaccinated as of Dec. 5. The most recent census data reveals Pennsylvania has 2.4 million individuals 65 and older.

Phil Galewitz: [email protected], @philgalewitz