Asthma Doesn't Hinder Chickenpox Vaccine
Thu August 14, 2003 08:41 AM ET
NEW YORK (Reuters Health) - Asthma or the steroid inhalers used to treat it seem to have no bearing on how the chickenpox, or varicella, vaccine works, new research suggests.
In contrast, steroids taken orally do seem to raise the risk of vaccine failure, the findings in the journal Pediatrics indicate.
A 1996 chickenpox outbreak raised concerns that the vaccine may not work as well in asthmatics. In that outbreak, which occurred among vaccinated children, asthmatics were seven times more likely to get chickenpox than non-asthmatics, Dr. Robert T. Chen, from the U.S. Centers for Disease Control and Prevention in Atlanta, and colleagues note.
To determine if asthma really is tied to vaccine failure, the researchers analyzed vaccination data for nearly 90,000 children enrolled at two health maintenance organizations.
Although several children did develop chickenpox despite being vaccinated, asthma and inhaled steroid use were not identified as risk factors for vaccine failure. Oral steroids, however, were associated with vaccine failure, but only when these drugs were prescribed after, not before, vaccination.
"The previous finding of asthma as a risk factor for vaccine failure may be attributable" to the fact that the study didn't account for the use of oral steroids, the investigators conclude. SOURCE: Pediatrics, August 2003.