Cockroaches are some of the oldest insects on earth and date back some 350 million years. There are over 4,500 different species, but only about 30 of these species are considered pests – commonly associated with filth, looking repugnant, and being extremely difficult to get rid of. Aside from simply appearing disgusting to people, they have been known to even transmit diseases between humans. By moving between filth and human food, they can cause disease, such as an outbreak in Southern California in the 1960s of Hepatitis A that was found to be spread by cockroaches. By shuttling around between humans, garbage, and food, they can also carry pathogens including E. coli, typhoid, salmonella, dysentery, plague, hookworm, staphylococcus, and streptococcus.
To make things worse, they are highly skilled at making their way into houses. Cockroaches can crawl through any crack or opening, and they can even fly for short distances. Once they inhabit a home, they create a musty, repulsive odor. Living off human waste is easy for them, as they not picky eaters. A cockroach diet in a household may include spilled food, trash, sewage, book bindings, and the fingernails, eyelashes, and human skin. Although their diet does not include human, cockroaches have earned a reputation for crawling into a person’s ear and getting stuck inside. Doctors have an easy time killing them by drowning them in oil, but they are very difficult to pull out afterward. Human experiences with cockroaches generally are not very pleasant, but only five percent of cockroaches are the types that humans encounter in their homes. The other 95 percent live entirely apart from humans; they also live in forests, in caves, under rocks in the desert, and next to lakes and rivers.