Cockroaches are equal-opportunity invaders. These nuisances can establish themselves wherever they can find reliable sources of food, water and shelter. Unfortunately, people’s homes are one of the major suppliers of all three of these cockroach necessities.

In fact, according to the National Pest Management Association, a whopping 78 to 98 percent of homes in urban areas host cockroaches, even though homeowners may never detect their presence. Cockroaches are nocturnal creatures and experts at hiding. If you do see one cockroach, many more may be lurking nearby.

These numbers may be alarming, but are cockroaches more than pests? Are they actually a danger to you and your family? Cockroaches aren't known to bite, but some common species do have heavy leg spines that can scratch your skin. More importantly, cockroaches are potentially harmful to your health.


Cockroaches are not the most sanitary insects. They feed on garbage, breed in sewage and lay waste all over your kitchen counter. One look at their daily habits may have you wondering, “Are cockroaches harmful?” There are a few things to consider.


Cockroaches can carry pathogens that may cause disease. One study at Cambridge University identified 30 different species of bacteria associated with cockroaches living in close proximity to humans (across 50 different apartments). Although cockroaches haven’t been linked to any specific outbreaks, they may play a role in spreading certain infections. According to the World Health Organization, cockroaches are known or suspected carriers of the microorganisms that can cause diarrhea, dysentery, cholera, leprosy, plague, typhoid fever and viral diseases, such as poliomyelitis. Though they likely won't be the main cause of a disease spreading, they can play a supplementary role.


Cockroaches cause many people anxiety. The appearance of one in a home may cause some to feel self-conscious or judged. Because of this, many people have established a fear of cockroaches. They might ask, “Are cockroaches poisonous?” or “Are roaches dangerous if they are living in your home?” Cockroaches do not produce any form of poison and have no ability to sting. In rare circumstances, they have been known to bite people, but this is not a common occurrence.


Current research shows that asthma and other allergies can be worsened by the presence of cockroaches. Asthma is one of the most prevalent causes of hospitalization in children. According to the Mallis Handbook of Pest Control by Arnold Mallis, “About 26 percent of the U.S. population is sensitive to German cockroach allergen by skin-test.”

Cockroaches produce a protein that can prompt an allergic reaction in many people. Their saliva, waste, moltings (shed skin) and even the dead members of their colonies can all serve as triggers.