Mosquitoes are small insects in the family Mosquitoidae of the order Diptera. There are approximately 3300 species of mosquitoes worldwide, with 400 species discovered in China. Mosquitoes are distributed around the world. Adults prefer to inhabit concealed, dark, and poorly ventilated places. Indoors, they often live under beds, behind cabinets, doors, in crevices in walls, as well as in animal pens and basements. Outdoors, they often live in grassy areas, caves, cellars, bridge openings, stone crevices, and other places. Female mosquitoes start sucking blood 2-3 days after eclosion, while male mosquitoes do not suck blood and feed on plant sap. Mosquitoes not only bite, suck blood, and disturb the human body, but also spread diseases. There are four mosquito borne diseases in China, namely dengue fever, Japanese encephalitis, malaria, and filariasis.

Cockroaches generally refer to insects belonging to the "cockroach" (scientific name), belonging to the arthropod, insects, cockroaches (Blattaria), commonly known as cockroaches, are common medical insects. Among them, only about dozens of species will invade human homes, and there are several species that are kept by humans as pets and as food for pets. Most of the species can only be seen in wild mountain streams and forests or insect museums. The most common cockroach at home, the big one is about 5.0cm long.