Why do some people get the flu even though they got a flu shot? A research study published in the Journal of the American Medical Association indicates that exposure to common environmental toxins may be reducing the effectiveness of some vaccinations and potentially damaging immune systems.
Deborah Kotz reports for The Boston Globe:
The researchers measured levels of perfluorinated compounds (PFCs) — found in food packaging, stain-resistant carpets, and nonstick pans — in nearly 600 children who lived in the Faroe Islands in the Norwegian Sea and found that those who had the highest levels of PFCs had a 50 percent lower reaction to tetanus and diphtheria vaccines.
Daniel Cressey reports for Nature:
This reduced response could mean that PFCs harm the immune system, says Philippe Grandjean, an environmental epidemiologist at Harvard School of Public Health in Boston, Massachusetts [and the University of Southern Denmark in Odense] and lead author of the paper. Previous research by his team has shown that another widespread class of compounds, polychlorinated biphenyls (PCBs), is also linked with immune damage.
Grandjean told Kotz that he isn’t worried that kids will get diphtheria or tetanus, which are rare conditions, but that PFCs could be interfering with other immunizations. He added to Cressey that “it’s likely this is going to be a programming effect that is going to stay with these kids for their whole lifetimes.”
PFC levels are similar in people in the Faroe Islands, the U.S., England, and Denmark.
Though the news is not good, there is no reason for parents to panic, according to other medical professionals not involved with the study who spoke with The Boston Globe. Kotz notes the other studies have shown the other things can interfere with immunizations. Citing a 2009 clinical trial published in the journal Lancet, she writes the researchers “found that administering acetaminophen to infants before vaccinations led to fewer fevers and febrile seizures but also reduced the immune response to common vaccines.”
Margie Peden-Adams, a toxicologist at the University of Nevada in Las Vegas, told Nature that the team’s work adds evidence to a link between PFCs and immune suppression. She said the next step will be to test different populations. Grandjean’s team is planning to study another group of Faroese children and children in Greenland.
Some PFCs are being phased out by at least one manufacturer. But the health effects of the chemicals may linger because of their use in consumer products is widespread and they are persistent environmental pollutants.
Source: “Manufacturing chemicals may damage the immune system,” Nature, 1/24/12
Source: “Vaccine effectiveness reduced by common environmental toxin, Harvard study finds,” Boston.com, 1/25/12
Image by eyeliam, used under its Creative Commons license.
Rachel Petkewich is a freelance science writer and editor. She has worked as a research scientist in the chemical industry and spent eight years as a staff writer and editor at various science journals and magazines, including Chemical & Engineering News.