The Truth about Cockroaches and Health

Cockroaches live in a wide range of environments around the world.

Cockroaches are most active when the temperature is greater than 70 degrees Fahrenheit and they thrive in warm environments with easily accessible food and water. These insects are mainly nocturnal and will run away when exposed to light. Amazingly, some cockroaches have been known to live up to three months without food and a month without water.

Cockroaches have many negative consequences for human health because certain proteins (called allergens) found in cockroach feces, saliva and body parts can cause allergic reactions or trigger asthma symptoms, especially in children. 

Cockroach allergy was first reported in 1943, when it was noted that certain patients developed skin rashes immediately after the insects crawled over their skin. Allergy skin tests were developed in 1959, which confirmed patients' cockroach allergies. Subsequent studies have firmly established that cockroach allergens can act as a trigger for acute asthma attacks.

The National Cooperative Inner-City Asthma Study (NCICAS) found that asthmatic children with both a positive skin prick test to cockroach allergen, and a high exposure to cockroach allergen in the bedroom were more likely to have wheezing, missed school days, nights without sleep, and unscheduled medical visits and hospitalizations for asthma. Approximately 23 percent to 60 percent of urban residents with asthma are sensitive to the cockroach allergens. However, the risk of asthma from cockroach allergen exposure and allergy is not limited to children. The study also found that cockroach allergy was associated with more severe asthma among elderly asthmatics in New York City.

Cockroaches can also passively transport microbes on their body surfaces including pathogens that are potentially dangerous to humans. Cockroaches have been implicated in the spread 33 kinds of bacteria, including E. coli and Salmonella species, six parasitic worms and more than seven other types of human pathogens.

E. coli and Salmonella are classic causes of food poisoning, or gastroenteritis. Common symptoms include belly pain, severe stomach cramps and tenderness, diarrhea which can sometimes be bloody, nausea and vomiting. Some people can experience severe diarrhea, which will cause dehydration and may require hospitalization. In rare cases, the bacteria can spread to the blood stream and cause life threatening infections.