What caused plagues? filthy conditions streets water animals

ANSWER:

Animals causes plagues.

EXPLANATION:

Plague is a serious infectious disease caused by a type of bacterium named Yersinia pestis. These bacteria are usually found in rats, rodents and other mammals. In humans, it is transmitted through fleas. It is also known as Black Plague or Black death, as it can kill a person affected by it, if not treated carefully. There are 3 forms of plague, in which "bubonic plague" is the most common and dangerous one.

Cultural convergence is the theory that two cultures will be more and more like each other a very notable example of this is around the u.s.-mexico border, where 

5×^2+20-15 or -(5x^2-20+15)