Do tea, coffee drinkers have lower "superbug" risk?

People who regularly drink tea or coffee may be less likely to carry the antibiotic-resistant "superbug" MRSA in their nostrils, a new study suggests.

Researchers found that of more than 5,500 Americans in a government study, those who drank hot tea or coffee were about half as likely as non-drinkers to harbor MRSA bacteria in their nostrils. Exactly what it all means, though, is unclear.

MRSA (pronounced "mersa") stands for methicillin-resistant Staphylococcus aureus, a type of bacteria that causes staph infections that are resistant to several common antibiotics. In hospital patients, MRSA can cause life-threatening pneumonia or blood infections. In the general public, it typically causes painful skin infections, but those can sometimes develop into serious invasive infections.

A small segment of the population -- about one percent -- carries MRSA in the nose or on the skin but does not get sick.

For the new study, reported in the Annals of Family Medicine, researchers looked at whether coffee or tea drinkers were any less likely than other people to harbor MRSA in the nose.

The idea for the study came from the fact that, in both the lab dish and in humans, topically applied or inhaled tea extracts have shown some anti-MRSA activity, explained lead researcher Dr. Eric M. Matheson, of the University of South Carolina, Charleston.

Less research has been done on coffee compounds, he told Reuters Health, but there is some evidence of antibacterial powers there as well.

Matheson's team found that, indeed, tea and coffee drinkers were less likely to carry MRSA.

Overall, 1.4 percent of the study group harbored the bacteria in their noses. But those odds were about 50 percent lower among people who said they drank hot tea or coffee, versus non-drinkers.

The big caveat, though, is that the link does not prove that tea or coffee, themselves, are the reason for the lower risk.

The study shows an association between the two, Matheson said, "but you never can conclude causation from an association."

"I can't tell you that this finding isn't just a coincidence," he said.

The researchers tried to account for several other factors -- like whether differences in age, income or self-rated health explained the difference between tea or coffee drinkers and non-drinkers. And the beverages were still linked to lower odds of being a MRSA carrier.

But, Matheson said, there could still be other explanations for the connection.

For now, he stopped short of recommending that people start drinking coffee or tea in the hopes of fending off MRSA.

"Based on one association study, that would probably be saying too much," Matheson said.

Another question is, even if coffee and tea drinkers do have a lower chance of carrying MRSA, are they any less likely to get sick? Matheson said there is still debate about whether MRSA carriers are at increased risk of developing an active infection.

It's estimated that in 2005, MRSA caused severe infections in 95,000 Americans, killing nearly 19,000.

The rate of hospital infections has gone down in recent years, according to the Centers for Disease Control and Prevention, but MRSA infections in the general population have been on the upswing since the 1990s and have shown no reversal yet.

To cut the risk of contracting the superbug, experts advise that people regularly wash their hands, keep skin wounds covered, and avoid sharing personal items like towels, washcloths and razors.

And those preventive steps are key, Matheson noted, whether you're a java lover or not.


/Reuters/