Poor home sanitation and residents' tolerance regarding German cockroaches were a good predictor of the pest's presence in their apartments, according to a Rutgers study in Paterson and Irvington, New Jersey.

The study in the Journal of Economic Entomology included interviews with senior citizen and disabled residents in 388 apartments in seven apartment buildings. Apartment conditions were also checked and glue traps placed to detect cockroaches.

The researchers found 29 percent of surveyed apartments had German cockroaches (Blattella germanica), a high rate compared with the rest of the society. Surprisingly, 35 percent of residents in apartments with cockroaches were unaware of their presence. This is alarming because lack of awareness allows cockroaches to reproduce, contaminate food, spread to neighbors, leave cockroach allergens that can affect human health and diminish future infestation control efforts.

The study also found that apartments with a "poor" sanitation rating in kitchens and bathrooms were 2.7 times more likely to have cockroaches than cleaner apartments. Residents who were more tolerant of cockroaches also had higher rates of cockroach infestation and higher cockroach numbers in their apartments.

Researchers concluded that improving cockroach control in these communities will require educating residents on the dangers of infestation and helping them to improve housekeeping through education and assistance from community and housing management.