How Rats and Fleas spread the Black Death

Whilst the black death was spreading in medieval times, it was not only caused by interaction and contact between humans. It was also not only caused by the people back then having poor hygiene. But was also caused by rats and fleas, they actually had a big role in spreading the disease. 

It's good that people had recorded the symptoms and cures also what had caused the Black Death. So we can always be cautious in a time like this happening again in the future. Luckily due to modern medicine, there is a cure to Black Death now, and there is only an 11% chance of dying when having the Black Death. Because we have antibiotics, there actually have been people who had black death even after the outbreak in medieval times. But luckily only a few, to be honest, I am very happy that I was born in the 21st century.

Here is a chart I made about rats and fleas:

Rats in general	Black rats	Brown rats	Fleas
- Rats can spread more than 35 diseases. - At most, a rat can weigh up to 230 grams. - The estimated lifespan of a rat would be 2 years at the most. - Rat teeth never stop growing. - A female rat can reproduce every three weeks, and give birth to about 10 babies each time on average. - Rats are very infectious.	- They live up to 12 months in the wild. But at the most 1 - 4 years. - Known as a ship rat, roof rat, or house rat. - They weigh up to 75 - 230 grams as an adult. - They are accomplished climbers.  - Females are more aggressive than males. - They are Omnivores.	- Known as a street rat, sewer rat, Hanover rat, Norway rat, Norwegian rat, Parisian rat, or wharf rat. - Their average lifespan is 1 - 3 years. But two years in the wild. - Most common rat. - They weigh up to 200 - 300 grams. - They can live a month without food. - They eat almost anything that is edible, even small animals.	- Fleas transport themselves on rodents and other mammals. - They are parasites that feed on blood. - Fleas can live on any warm-blooded animals. But prefer to live on us human cats, dogs, and rodents. - They can jump as high as 150 times their body height.

Here is my diagram of the cycle of the Black Death.