Flu Vaccine Effects Uncertain in Immunocompromised
Such individuals appear to be at greater risk of flu complications; vaccination seems safe
THURSDAY, July 23 (HealthDay News) -- Though roughly 1 percent of the U.S. population is immunocompromised for a variety of reasons, data on the efficacy of influenza vaccines in these individuals are scarce, according to research published in the August issue of The Lancet Infectious Diseases.
Ken M. Kunisaki, M.D., of the Minneapolis Veterans Affairs Medical Center, and Edward N. Janoff, M.D., of the University of Colorado Denver School of Medicine in Aurora, reviewed the effects of influenza infection and vaccination in immunocompromised populations, including those with HIV/AIDS or organ or bone-marrow transplants, and those taking chemotherapy for cancer or systemic corticosteroids for other conditions.
The researchers note that, in general, people who are immunosuppressed have a higher risk of complications associated with influenza and have a tendency for impaired humoral responses to vaccines. However, vaccination appears to be safe, though long-term data is lacking.
"We encourage further clinical trials with relevant clinical outcome measures, as opposed to surrogate outcomes like vaccine-induced antibody titres. We would particularly welcome randomized trials comparing standard influenza vaccine with active comparators such as modified vaccines or antiviral prophylaxis with or without vaccination. Such data would greatly enhance our ability to make more informed vaccination recommendations for this population, particularly in situations of vaccine shortage or pandemic influenza," the authors conclude.
The authors reported financial relationships with GlaxoSmithKline, MedImmune Inc., and VaxInnate Corporation.