Staphylococcus aureus, also known as the dreaded Staph bacteria that can cause lethal infections, is commonly found in the human nose. The germ is also estimated to cause infections killing 18,000 people every year in the U.S.
But the potentially deadly unwelcome guests are a product of environment, not genes – and can be pushed out by benign bacteria, according to an international study of twins.
“This is study is important because it suggests that the bacteria in the nose are not defined by our genes and that we may be able to introduce good bacteria to knock out bad bugs like Staph,” said Lance Price, the director of the Translational Genomics Research Institute’ Center for Microbiomics and Human Health. “Using probiotics to promote gut health has become common in our culture. Now we’re looking to use these same strategies to prevent the spread of superbugs.”
The nasal microbiome is the collection of bacteria and germs living deep within the nose. The scientific team – which included the Statens Serum Institut and the Milken Institute at George Washington University – analyzed 46 identical twins and 43 fraternal twins through the famed Danish Twin Registry.
They found there is “no genetically inherent cause for specific bacteria in the nasal microbiome,” said Paal Skytt Anderson, of the Statens Serum Institut.
Instead, the bacteria appear to be determined by the environment. Other bacteria could be cultivated, instead, to prevent the buildup of Staph, the scientists believe.
They also found, contrary to previous studies, that men are not at higher risk for Staph nasal colonization.
“We believe this study provides the early evidence that the introduction of probiotics could work to prevent or knock out Staph from the nose,” said Cindy Liu, a pathology resident at Johns Hopkins Schools of Medicine, who was also the study’s lead author. “This was a surprising finding.”
Stanford investigators first recognized that about a third of all people carry significant amounts of Staph deep in their nasal passages, in a 2013 study. Another third occasionally carry the germ, and the remaining third appear to never carry the bacteria in their noses, they found.