Q. My son said he was bitten by a cockroach while sitting at the kitchen table. He watched it crawl onto his hand and bite him! He doesn’t have a welt or anything. Do they spread diseases with their bite?                           

A. Cockroaches are capable of biting (more like a “nip”) but they do not do so on purpose. There have been cases where cockroaches apparently caused small bites on the faces of children. These bites almost certainly happened accidentally when cockroaches were attempting to feed on dried food or milk left around the mouths of sleeping children. Something similar may have happened to your son; he may have had food residue on his hands that attracted the cockroach.

Keep in mind that cockroaches will eat anything, especially when food is in short supply. There have been historic reports of cockroaches gnawing on callused skin, fingernails, toenails, and eyelashes of people. These chewings or “bites” usually happen to sleeping people, often children, and only in very high infestations. There were some reports in the olden days of sailors aboard ship having to wear gloves while sleeping to keep the hordes of cockroaches on board from gnawing on their fingernails!

Most of these cases are attributed to larger cockroaches like the American cockroach, not the more common German cockroach usually found in homes. This makes sense because the larger the roach, the stronger the jaws, and the more likely that skin could be punctured. A bite from the smaller, more common German cockroach may not even be felt. Cockroaches can carry a lot of germs on their body because of the places they frequent and the things they feed on. If a cockroach bite broke the skin, germs could be transmitted through the bite, but that is not likely to happen. Cockroaches do not inject disease organisms when they bite like mosquitoes or ticks can.

In most cases, cockroaches are falsely accused of causing bites. The skin irritation may be real but is related to environmental or other causes and not to cockroaches. Some bites attributed to cockroaches may actually be from a parasitic mite that feeds on cockroaches. This mite may attempt to feed on people if cockroaches are not available, causing skin irritation. Needless to say, in the rare case where the “bites” really are from cockroaches, you are dealing with a large and serious cockroach population that is facing a food shortage. Chewing on people is definitely not the first food choice for cockroaches!