Swine Flu Shots Safe for People With Weak Immune Systems: Experts

Sept. 19 -- FRIDAY, Sept. 18 (HealthDay News) -- The H1N1 swine flu vaccines approved this week by the U.S. Food and Drug Administration can be safely used by people with compromised immune systems, according to new recommendations from the American Academy of Allergy, Asthma & Immunology.

These would include people whose immune responses are weakened by medical treatments (such as for cancer or organ transplant) and those infected with HIV, the experts said.

Influenza vaccines can be made from live -- but modified and weakened -- virus, or they can be made from the harmless byproducts of the virus (so-called "killed" virus vaccines). According to the experts at the American Academy of Allergy, Asthma & Immunology (AAAAI), all of the injected H1N1 vaccines so far approved by the FDA are of the "killed" variety.

"There's never any harm with giving killed influenza vaccine" to immuno-compromised individuals, said Dr. Kenneth Bromberg, director of the Vaccine Research Center at The Brooklyn Hospital Center in New York City.

There is one vaccine out there that those with weakened immune systems should avoid: the nasal spray form of the flu vaccine, FluMist. FluMist is already available as a seasonal flu vaccine, and 3.4 million doses of an H1N1 version of FluMist are expected to be distributed nationally the first week of October, CDC officials announced Friday.

FluMist is derived from live (but very weakened) virus, so it could pose a problem for people with poor immune systems. The recommendation to avoid FluMist extends to people living in close proximity to an immune-compromised person, such as family members, because they could pass on the live virus to that individual, the AAAAI said.

No such threat exists for average Americans with robust immune responses, the experts said.

One question for some people with compromised immune systems is whether the flu shot will actually help them, given their poor immune defenses.