Something wicked lurks in the folds of many kitchen towels. They’re unseen. They’re potentially harmful. And they won’t help with the dishes.

A collection of bacterial pathogens that can cause food poisoning, including E. coli, was found on nearly half the kitchen towels tested by researchers after one month’s use, according to a new study.

During that month, some of the towels may have been hand washed, though not in a washing machine.

Researchers tested 100 towels that were distributed to homes on the island nation Mauritius in the Indian Ocean. Of the 49 that were contaminated, the study found three-quarters were contaminated by bacteria usually found in the human intestine. Another 14 percent contained staph bacteria, often found on hands.

Researchers, who presented their findings at the annual meeting of the American Society of Microbiology, also found that three-quarters of cotton towels that were tested had bacterial growth. Bacteria grew on 42 percent of nylon towels and about a third of nylon/cotton combinations. Cotton, researchers noted, is more absorbent, allowing more time for bacteria to bloom.

Wet or moist towels appeared to be a better breeding ground for bacteria than dry towels. The same was true of towels used for multiple purposes, such as drying hands and utensils and cleaning table surfaces.

Other factors that increased the risk that a towel would be contaminated with bacteria included large families, being poorer and families with children.

The lesson in all of this? A kitchen towel shouldn’t linger too long before it’s sent to the washer. Researchers suggest doing so every other day to keep the pathogens at bay.