It is picked up rurally from swimming in contaminated lakes and reservoirs. Leptospirosis can also be contracted by rubbing eyes with dirty hands. People with open cuts and wounds are especially vulnerable to the bacteria, as it can be picked up almost anywhere. As the rat population in cities grows, so does the potential for contact with this disease. Leptospirosis typically causes aches, pains and fever that go away on their own.
Victims can die if they develop serious kidney or liver complications.
In extreme cases, death follows three to six days after infection. The disease is treatable with antibiotics. In November 1998 leptospirosis killed eight people and hospitalized one hundred in China. Another disease passed on through rat urine is hantavirus. It is transmitted to humans through breathing in particles of an infected rodent's urine, droppings or saliva.