Flu

High-Dose Flu Vaccine Better for Some Elderly Patients

New research suggests that a high-dose inactivated influenza vaccine is a more viable option for frail, older flu patients living in long-term care.

A team led by investigators from the University of Pittsburgh Medical Center conducted a randomized, single-blind trial comparing high-dose to standard-dose inactivated influenza vaccine in 205 frail and elderly residents of long-term care facilities during the 2011-2012 and 2012-2013 flu seasons, measuring hemagglutination inhibition (HI) antibody titers at baseline and 30 and 180 days following vaccination.

______________________________________________________________________________________________________________________________________________________________________
RELATED CONTENT
Vaccine May Lower Risk of Flu by 58% in Older Adults
CDC: 2014-2015 Flu Season May Be Severe
______________________________________________________________________________________________________________________________________________________________________

Throughout the course of the 2 flu seasons, participants were randomly assigned to receive either high or standard doses of the appropriate vaccine for the season. In both seasons, 1 of the strains contained in the vaccines was the H1N1 pandemic strain, while the other A strain and the B strain differed.  A total of 187 subjects completed the study, according to the authors.

In total, 187 subjects completed the study, according to the authors, who report that the higher dose—which was approved for individuals age 65 and older in the year 2009—produced greater immune responses in 4 out of 5 strains contained in the vaccines.

The advantage of the high-dose vaccine “is in reducing the likelihood of influenza infection and complications; its use does not impact treatment plans,” says Richard Zimmerman, MD, MPH, a professor in the department of family medicine at the University of Pittsburgh Medical Center, and study co-author.  

“Because residents of long-term care are at high risk for complications and at high-risk for infection due to being in close proximity, antivirals should be used when a resident contracts influenza,” says Zimmerman.

“Long-term care residents are particularly at risk for influenza and influenza-related complications,” adds David Nace, MD, MPH, director of the long-term care and influenza programs in the division of geriatric medicine at the University of Pittsburgh Medical Center, and lead author of the study.

There are many reasons for this, including age-related immunosenescence, comorbid medical illnesses, use of medications that may impair the immune system, poor nutritional status and the nature of the long-term care environment itself, he says, adding that “we know that vaccine effectiveness decreases with increasing age.  As a result, there is a clear need for more effective vaccine options in this vulnerable population.”

In addition, the low antibody levels found in long-term care residents highlights the importance of using a “bundled approach” to influenza prevention, says Nace.

“Resident vaccination alone will not be enough,” he continues, noting that a bundled approach would include vaccination of healthcare workers; active surveillance for influenza-like illness; early institution of droplet isolation precautions; use of social distancing interventions such as cancelling large group activities, limiting visitations, and avoiding congregate meals; prompt confirmatory testing with accurate diagnostic tests; and rapid deployment of antiviral agents for both treatment and prophylaxis.

“And, as always,” says Nace, “we should remind everyone of 2 time-proven simple interventions—cover your cough and wash your hands.”

—Mark McGraw

Reference

Nace D, Chyongchiou J, et al. Randomized, controlled trial of high-dose influenza vaccine among frail residents of long-term care facilities. J Infect Dis. 2014.