Adult German cockroaches are 1/2 to 5/8 inch long and tan to light brown. Although they have fully developed wings, they do not fly. Nymphs are similar in appearance to adults except that they are smaller and lack wings. The German cockroach is best identified by its small size and near two dark parallel lines running from the back of the head to the wings. They are usually found in kitchens near dishwashing machines, stoves, sinks, and in bathrooms of homes.
German cockroaches usually prefer a moist environment with a relatively high degree of warmth. The insects are mostly scavengers and will feed on a wide variety of foods. They are especially fond of starches, sweets, grease, and meat products. In many locations, garbage is a principal food source. As with other species, German cockroaches are mostly active at night, when they forage for food, water and mates. During the day they hide in cracks and crevices and other dark sites that provide a warm and humid environment.
Different forms of gastroenteritis include food poisoning and diarrhea appear to be the principal diseases transmitted by German cockroaches. The organisms causing these diseases are carried on the legs and bodies of cockroaches and are deposited on food and utensils as the cockroaches forage. Cockroach excrement and cast skins also contain a number of allergens to which many people exhibit allergic responses, such as skin rashes, watery eyes and sneezing, congestion nasal passages and asthma.
A key factor in prevention is sanitation. Clean up spilled foods, including crumbs on the floor. Do not leave dirty dishes overnight. Store items such as cereal, crackers, cookies, flower, sugar, and bread in airtight seal containers. Structural modifications such as caulking holes in walls were pipes may be necessary in the kitchen, bathroom and other areas of the house in order to control German cockroaches. Some treatment methods may include: chemical treatments, aerosol fogging, gel baiting, dusting wall voids, installing glue monitor traps and grow regulators.