How did fleas contribute to the black plague?

Answer 1

Yes. One of the peculiar characteristics of the Black Plague is that it blocked the digestive system of the infected flea. As a result, the fleas starved. The starving fleas were far more likely to bite than healthy fleas.

Answer 2

Contrary to popular belief, rats did not directly start the spread of the Bubonic Plague. It is mainly a disease in the fleas (Xenopsylla cheopis) that infested the rats, making the rats themselves the first victims of the plague. Infection in a human occurs when a person is bitten by a flea that has been infected by biting a rodent that itself has been infected by the bite of a flea carrying the disease. The bacteria multiply inside the flea, sticking together to form a plug that blocks its stomach and causes it to starve. The flea then bites a host and continues to feed, even though it cannot quell its hunger, and consequently the flea vomits blood tainted with the bacteria back into the bite wound. The bubonic plague bacterium then infects a new victim, and the flea eventually dies from starvation. Serious outbreaks of plague are usually started by other disease outbreaks in rodents, or a rise in the rodent population.

Answer 3

The fleas were the actual carriers of the plague. The fleas, preferentially sought out rats, not humans, but would bite humans, of course. The problem was that at that time in history, anywhere there were humans, there were rats. Lots of rats.

Answer 4

The fleas acted as carriers between the rats and humans and between infected and healthy rats.

Rat fleas, unlike human fleas develop a blockage in their digestive system when infected with the plague, this causes them to abandon the host rat and seek food elsewhere. If they jump onto a human and bite them, instead of getting more blood they end up injecting the infected rat blood in their system into the person's bloodstream, directly infecting them with the plague.

This would happen more often if rats died after taking shelter in people's houses. The fleas actually starve to death as they cannot digest anything but continue to try and feed until this happens.

Answer 5

No, they were the carriers. The fleas lived. The people died.