The American cockroach (Periplaneta americana), also colloquially known as the waterbug, but not a true waterbug since it is not aquatic, or misidentified as the palmetto bug (see Florida woods cockroach for the differences), is the largest species of common cockroach, and often considered a pest. It is also known as the ship cockroach, kakerlac, and Bombay canary. They are native to Africa and the Middle East. Despite their name, they are believed to have been introduced to America and the New World only from the 17th century AD onwards as a result of human commercial patterns.
Despite the name, none of the Periplaneta species is endemic to the Americas; P. americana was introduced to what is now the United States from Africa as early as 1625. They are now common in tropical climates because human activity has extended the insects' range of habitation, and are virtually cosmopolitan in distribution as a result of global commerce. American cockroaches are also known as plagues in the warm Mediterranean coast of Spain, as well as in southern Spain and southern Portugal (starting from Barcelona to the Algarve) and in the Canary Islands, where the winters are mild/warm and frost-free, and the summers are hot.
Cockroaches date back to the Carboniferous period. They are thought to have emerged on the supercontinent Pangaea, or on Gondwana, the daughter continent of Pangaea. The cockroach made many adaptations over the years to be able to survive the major die-offs to which many species succumbed. However, like all the extant species, the American cockroach has probably evolved in the last few millions to thousands of years (during the Quaternary) and is a fully modern organism.
Risk to humans
The odorous secretions produced by American cockroaches can alter the flavor of food. Also, if populations of cockroaches are high, a strong concentration of this odorous secretion can be present. Cockroaches can pick up disease-causing bacteria, such as Salmonella, on their legs and later deposit them on foods and cause food poisoning or infection if they walk on the food. House dust containing cockroach feces and body parts can trigger allergic reactions and asthma in certain individuals.
Control as pests
In cold climates, these cockroaches may move indoors when the weather turns cold, seeking warmer environments and food. Cockroaches may enter houses through sewer connections, under doors, or around plumbing, air ducts, or other openings in the foundation. Cockroach populations may be controlled through the use of insecticides. Covering any cracks or crevices through which cockroaches may enter and cleaning any spills or messes that have been made is beneficial, so cockroaches are not able to enter and are not attracted to the food source. Another way to prevent an infestation of cockroaches is to thoroughly check any material brought inside. Cockroaches and egg cases can be hidden inside or on furniture, in boxes, suitcases, grocery bags, etc.