Rat Fleas
The rat flea is a minute parasite that feeds on the blood of rodents. They are known carriers of a variety of diseases and are considered the cause for the spread of the bubonic plague. Infection is transmitted after a flea feeds from an infected rodent and then bites a human. Through biting, rats also transmit the diseases carried by rat fleas.
Rat fleas begin as white eggs, which drop from the female and hatch on the ground or in the fur of an animal. Emerging larvae are approximately two millimeters in length and appear similar to small, legless worms. Unlike adult rat fleas, larvae do not consume blood, but instead eat flea droppings, dead skin cells and other small parasites. Larvae spin white, silken cocoons within which they pupate for 24 days to six months. After emerging from the pupae, rat fleas are capable of drawing blood and reproducing. Adults live for approximately one year and prefer to inhabit warm environments.
Adult rat fleas have two eyes but are only able to register light. They sense their surroundings through the use of genial and protonotal combs, as well as antennae. The mouth of the rat flea is used to emit saliva and draw blood. Fleas are incapable of flight, but can jump up to 200 times the length of their bodies and 130 times their own height.