People with a sensitivity to cockroaches often develop a rash if one of these insects crawls over their skin.
Direct contact with these insects is not generally the main problem.
Cockroach infestations cause a high level of feces and body parts from dead insects, as well as saliva. Long term exposure can eventually cause some people to become sensitive to cockroach contamination, causing an allergy.
This is a similar problem to dust mite allergies, the main difference being that cockroaches are physically bigger (and more discussing) than dust mites.
This is particularly a problem with inner-city children who are more likely to live in an infested home. Many hospital visits dealing with an asthma attack can be attributed to cockroach allergens.
In some areas, most homes have a cockroach problem. A house can harbor thousands or even hundred’s of thousands of insects, generating a very large amount of air-bourn allergens within the home.
If you see just a single insect, you can be almost certain that it represents hundreds or thousands of others, hidden in cupboards, in walls, under the sink, behind the fridge etc.
The insects or their eggs can hitch a ride into your home with groceries, second hand furniture and other items brought into the home. In some areas they may simply crawl in from the outside.
Apartment buildings are worse, since once one unit gets infested, the insects can easily find their way into other units.
The best way to deal with a cockroach allergy is to get rid of the insects. Hire a professional pest control company, and if possible, stay out of the house for several days to minimize your exposure to the toxic chemicals used to exterminate cockroaches.
The image at the top of this article shows: A. German cockroach, B. American cockroach, C. Australian cockroach, D&E. Oriental cockroach (? & ?).