Cockroach can be serious problems for people if they come into close association with their dwelling. They may affect human health in several ways including food contamination, psychological stress, allergy through their odorous substances and other allergens, biting and pathogen transmission. People are generally repulsive to cockroaches and their presence in a building is a clear indication of lack of sanitation.
Cockroaches have the potential to contaminate food if proper care is not taken. This is primarily because cockroaches can feed virtually on any organic material including feces. In fact cockroaches are often found in toilets and thus may mechanically transport bacteria or other microbes on their legs and contaminate foods in kitchen and other living areas. They may also contaminate food with their excrement. They are generally considered as an indication of poor sanitation in an environment.
Although most people have a tolerance for the presence of cockroaches, some find them disgusting and may develop some phobia and psychological stress. It is clear that most people have an aversion for cockroach, but some may be irrational in their behavior of thinking that they have a large infestation of cockroach although that may not be the case.
The presence of cockroaches in an environment may be considered as a sign of poor sanitation However, this is not always the case. Some peridomestic species of cockroach such as the American cockroach usually infest urban sewage systems as well as septic tanks and may move into houses through the pipe that connects homes (reference).
In some places like restaurants and hotels their presence may not even be tolerated. In all cases, poor sanitation significantly contributes to the establishment of cockroach colonies. People may also become allergic to cockroach odors and may develop some respiratory conditions.
High infestation of cockroach usually produce a characteristic odor that may cause allergy to humans. These odors may also be nauseating, and cockroach-contaminated food may cause people to vomit. You can read more about cockroach allergy here.
There is few account of cockroach biting and in general, cockroach does not bite human beings unless no other food material is available for them. There is few documentation of cockroach biting human as reported by (Richard ). It is also the report of cockroach bites around the mouths of children in hospitals. These bites may result in inflammation and blistering (reference)
Pathogens Transmission to Humans and Animals
Although cockroaches are generally considered as nuisance pests they can have medical implications. The transmission of pathogens by cockroaches is often controversial as they do not act as common disease vectors like mosquitoes or ticks.
However, since domestic and peridomestic cockroaches are often associated with poor sanitation and close association with bathrooms and other unhealthy spots, they have the potential to acquire and disseminate pathogens among humans.
Pathogens transmission by cockroaches may be mechanical though their body parts especially their legs. Some cockroach species also harbor pathogenic organism such as bacteria and nematodes (reference) that they can transmit to human and domestic animals.
They also can serve as intermediate host and reservoirs of pathogens to domestic animals as reported by (reference). In all cases cockroaches do not pose significant public health issues and the problems associated with them can easily be solved through cleaning and sanitation.