Neither rats nor mice are poisonous. They are both very dirty and carry many diseases, and so do the fleas that are on them. As to which is more of a disease factory, I don't know. If I had to guess it would be rats.
Neither Rats or Mice are in essence poisonous. Neither secrete venom. However what i think the question is is "Do rats or Mice carry more diseases?" In which case there is some debate as to which would carry more diseases. Rats are known to carry the oriental rat flea which does carry Yersinia pestis, the organism responsible for Bubonic Plague. however mice carry other diseases which are equally lethal, and often harder to diagnose.
Rats that were infected by the disease and have died on the side of the street to easily spread the disease
the disease was carried by rats who were on the ship
The rats themselves do not spread disease, but the fleas that are in their fur was well known for spreading the Black Death in the Middle Ages.
The Black Death was spread by rats and the fleas they carried. The disease spread slowly across Asia as it moved through the rat population. Rats travelled on ships, which crossed the Mediterranean, and the rats got into various port cities, spreading the disease. The Black Death can be spread from person to person, but the spread is much slower and ends, in the absence of the rats and fleas.
It was spread by fleas carried by Black rats.
Rats can live anywhere and feed on just about everything. They can also carry disease. The Great Plague of London was spread by rats.
Rats and fleas carried the disease and spread it to the people of Europe.
It was not so much people that spread the disease as fleas from rats.
More properly, a LACK of science played a role. The means by which the Bubonic Plague was spread was unknown (disease spread by fleas from rats). It was blamed on night fogs, cats, and bad air. When the cats were killed, there were more rats to spread the disease.
The Black Death was brought to Britain by the fleas carried by rats. The rats travelled to Britain on ships and the disease spread out from the ports. Foul, overcrowded city slums proved an indeal breeding ground and the disease quickly spread.
The fleas on rats. The rats had a disease that the fleas got then jumped onto the people to spread the desease.
It was a bacterium that caused it, but rats and fleas between them were the vector which spread the disease.