Anyone who has ever had a bedbug infestation knows full well what a nuisance the pests can be. Unlike ticks and mosquitoes, however, bedbugs, which feed on human blood, are not known to spread disease and are generally not viewed as a major public health threat.

But a peer-reviewed study published online Wednesday in a journal of the U.S. Centers for Disease Control and Prevention suggests the pests could play a role in transmitting disease. In a tiny sample of bedbugs, collected from a small number of residents living in crowded conditions in a poor neighborhood in Canada, researchers found the drug-resistant bacterium known as MRSA.

The researchers at a Vancouver, B.C., hospital tested three patients from the neighborhood who were infested with bedbugs. Researchers collected five bedbugs and determined that the insects carried two types of drug-resistant bacteria. Three bedbugs from one patient contained methicillin-resistant Staphylococcus aureus (MRSA), and the two from the other patients each contained vancomycin-resistant Enterococcus faecium (VRE).