The European cockroach, also known as the German cockroach (Blattella germanica), is a pervasive insect that has adapted to live almost exclusively within human dwellings, making it a common household pest across the globe. The scientific record of this cockroach dates back approximately 250 years to central Europe, which is how it acquired its common name.
Identifying the European Cockroach
Adult European cockroaches measure between 13 to 16 millimeters (0.5 to 0.6 inches) in length. They have a light brown to tan color, with two distinct, dark, parallel stripes located on their back, just behind their heads, a region called the pronotum. These stripes distinguish them from other species.
Male European cockroaches are lighter in color and have a narrower abdomen compared to females. Females are wider and thicker, with a broadly curved abdomen that does not narrow at the end. Both sexes possess wings, but they rarely fly, preferring to run quickly.
Where They Live and What They Do
European cockroaches prefer warm, humid environments, thriving in temperatures around 25-30 degrees Celsius (77-86 degrees Fahrenheit). They are found indoors in residential and commercial kitchens and bathrooms, as these areas provide consistent access to food and moisture. They hide in dark, narrow cracks and crevices, such as behind appliances, in cabinets, under sinks, and within electrical equipment.
These cockroaches are nocturnal, often going unnoticed until their population grows considerably. They are omnivorous scavengers, feeding on human food, soap, glue, toothpaste, and decaying organic matter. A female European cockroach can produce four to eight egg cases, called oothecae, in her lifetime, with each case containing around 30 to 40 eggs.
Health Impacts
European cockroaches can pose several health concerns, primarily through their role as carriers of allergens and pathogens. They produce allergens in their saliva, feces, eggs, and shed exoskeletons, which can trigger asthma and allergic reactions in sensitive individuals. These allergens can contribute to poorer asthma outcomes, especially in children.
The insects can also passively transport microbes on their body surfaces, including bacteria like Salmonella and E. coli, which are known causes of food poisoning. They pick up these bacteria as they crawl through decaying matter and waste, potentially contaminating food, utensils, and food preparation surfaces. Their presence can contribute to foodborne illnesses and other health issues.
Keeping Them Out and Getting Rid of Them
Preventing European cockroach infestations involves a combination of sanitation and exclusion strategies. Sealing entry points like cracks around walls, doors, and utility pipes with caulk can deter their entry. Maintaining a clean environment is also important, including regularly cleaning countertops, stovetops, and floors to remove food crumbs, storing food in airtight containers, and promptly emptying garbage cans.
If an infestation is present, an integrated pest management (IPM) approach is recommended. This involves inspecting for hiding spots and assessing infestation severity. DIY methods include baits (such as gel baits) for quick results, and insect growth regulators (IGRs) that disrupt their reproductive cycle. For larger or persistent infestations, professional pest control services may be necessary, as they have access to a wider range of targeted treatments and expertise.