Hundreds of Bacteria Species Discovered on Human Skin

Human skin is crawling with bacteria, say U.S. researchers who identified more than 200 species -- 8 percent of which were previously unknown -- on samples collected from the forearms of six people.

The New York Medical School team used genetic analysis to detect the types of bacteria present on the volunteers' skin, BBC News reported.

An initial analysis detected 182 species of bacteria. Another test was conducted eight to 10 months later to see if there had been any changes. That second analysis revealed 65 more kinds of bacteria.

About half the species were already known to be common skin dwellers, but 8 percent had not been previously described in scientific literature. The researchers also found that about 75 percent of the bacteria species were unique to individuals, which suggests the skin is "highly diversified," BBC News reported.

The findings were published online in the journal Proceedings of the National Academy of Sciences.

"Over the years maybe about 50 different organisms have been found in human skin but we knew there were more organisms present" that couldn't be detected, study leader Martin Blaser, professor of microbiology, said in a prepared statement.

"We have now gone up five-fold from what's been known before," he said.

Experts say that bacteria plays an important role in keeping skin healthy, BBC News reported.

HealthDay News, February 6, 2007

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