Can Fleas Drink Human Blood?

Despite their small size, fleas are incredibly dangerous. They are thought to have contributed to the bubonic plague that killed a quarter of the population of Europe during the Middle Ages. This disease was spread by fleas feeding on human blood. While the actual causes of the plague are not entirely understood, fleas are thought to be a major cause of the disease.

The life cycle of a flea begins with the eggs laid by female fleas. These are oval, white and about half a millimeter in diameter. They are laid in the fur or bedding of their host. These eggs can stay dormant for long periods of time, and hatch only when the temperature and vibration of the host is right.

Humans don’t normally have fleas living on them. However, they do occasionally bite humans. Because human hair isn’t as hairy as that of dogs and cats, fleas are unlikely to live on humans for long. And even if they do live on humans, they are most likely to wash off.

Despite being an excellent source of nutrition for fleas, the insects do not prefer human blood over the blood of other animals. Adult fleas prefer the blood of pets, but they will feed on people if there is no warm-blooded animal in the vicinity.