Among the great unknowns of the COVID-19 vaccines now in use against the SARS-CoV-2 coronavirus is how long immunity lasts and whether booster shots will be needed over time.
Scientists at the VA's Office of Research and Development in White River Junction, Vermont, have found that the vaccines can provide immunity for at least seven to nine months -- a time frame similar to the immune response generated in people who have had COVID-19.
The study examined antibodies in some of the 240,000 veterans who have contracted COVID-19, Dr. Richard Stone, VA's acting under secretary for health, said Friday.
"The evidence is that between seven and nine months, we can feel comfortable that you are still protected. We think it will be longer than that. That is not a limitation," Stone said, speaking to reporters during a news conference Friday with VA Secretary Denis McDonough.
While several studies have shown that immunity following a COVID-19 infection can last at least six months, and perhaps as many as eight months, research on the lasting impact of COVID-19 vaccines is ongoing, and scientists have been hesitant to discuss the time frame before all the data is compiled.
But the VA's findings, Stone said, could "extend" the Centers for Disease Control and Prevention’s message that immunity from a vaccine lasts at least six months.
"Right now it appears we will be able to publish in the next few weeks," Stone said.
The results of yet-to-be published research should be treated with caution, as primary outcomes may differ from those in final publication.
Information on the long-term effectiveness of vaccines will help determine whether booster shots will be needed and help officials plan for a recurrent immunization program, Stone said.
"Hundreds of researchers and public health leaders, and I am one of those … believe this is an endemic disease just like influenza. How do we reduce mortality and hospitalization, and clearly it's the ability to deliver immunizations," Stone said.
As of Friday, VA had recorded 240,765 cases of COVID-19 and 11,218 deaths from the disease. VA has delivered 2,316,780 doses of the coronavirus vaccine and fully vaccinated nearly 1.7 million veterans.
VA now receives roughly 200,000 doses of the various COVID-19 vaccines each week, including those made by Pfizer, Moderna and Johnson & Johnson, and it has built a system designed to administer up to 300,000 a week for veterans enrolled in VA health care, according to McDonough.
But a law signed this week by President Joe Biden greatly expanded VA's vaccination mission, giving the department the authority to inoculate veterans, their spouses and caregivers who are not enrolled in VA health care.
McDonough said that VA is building a computer system needed to track vaccines administered to non-enrolled veterans and other eligible people. The VA's vaccine allocations will increase to 250,000 doses per week starting next week, he said.
"It may take us one to two weeks to get there," McDonough said about establishing a system to report non-enrolled veterans' information to the CDC. "We're working feverishly to get to where we need to be, because we want to get the vaccines in people's arms as fast as we can."
McDonough added that the biggest challenge for VA regarding vaccine distribution is in rural areas where vaccine hesitancy is more prevalent. VA has launched mobile units designed to get vaccines out to rural and "highly rural areas," and has completed 317 missions, with another 31 planned by May 1.
"While we are very happy to see [an] uptick among our veterans of color -- in fact, we are seeing less hesitancy among Black veterans than we feared we might see -- we have work to do on rural and highly rural veterans," McDonough said.
"There's not hesitancy [among most vets], and there needn't be hesitancy," McDonough said. "We're now seeing 2 million veterans vaccinated with very little associated problems."
The VA maintains a registry of its veteran patients who have had COVID-19. This registry is used for research, to monitor for lasting symptoms and to understand the long-term impact on health of the illness, according to Dr. Carolyn Clancy, acting VA deputy secretary.
Stone said the VA immunization research was done in conjunction with, and was partially funded by, the CDC and the Food and Drug Administration.
-- Patricia Kime can be reached at Patricia.Kime@Monster.com. Follow her on Twitter @patriciakime.
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