In some attics, there are so many rats that the droppings really pile up thick. I recommend that you
have the droppings cleaned if they are in high numbers, due to the odor and biohazard that they cause.
Not only can new rats smell the odor of previous rats, but the droppings may be dangerous to people.
Rats also urinate, of course, and one rat can urinate up to three gallons per year.
Rats often travel the same routes over and over again. Observe how they entered this portion of the
attic through a gap, and traveled a route along the wall. When trapping rats, it is important to place
the traps right on the travel routes. Rats are cautious by nature, and usually won't go out of their way
to seek out the traps. Trap location is the key to success.
Rats and squirrels can drag acorns and other nuts into an attic. Here we see droppings and chewed
nuts. This photo was taken on top of the box above a vent (part of the attic duct work).
Diseases Associated With Rat Droppings:
Information gathered from the Centers for Disease Control and Prevention
Hantavirus Pulmonary Syndrome (HPS): Hantavirus pulmonary syndrome (HPS) is a deadly disease transmitted by infected rodents through urine, droppings, or saliva. Humans can contract the disease when they breathe in aerosolized virus. HPS was first recognized in 1993 and has since been identified throughout the United States. Although rare, HPS is potentially deadly. Rodent control in and around the home remains the primary strategy for preventing hantavirus infection.
Leptospirosis: Leptospirosis is a bacterial disease that affects humans and animals. It is caused by bacteria of the genus Leptospira. In humans it causes a wide range of symptoms, and some infected persons may have no symptoms at all. Symptoms of leptospirosis include high fever, severe headache, chills, muscle aches, and vomiting, and may include jaundice (yellow skin and eyes), red eyes, abdominal pain, diarrhea, or a rash. If the disease is not treated, the patient could develop kidney damage, meningitis (inflammation of the membrane around the brain and spinal cord), liver failure, and respiratory distress. In rare cases death occurs.
Eosinophilic Meningitis: Eosinophilic meningitis is an infection of the brain occurring in association with an increase in the number of eosinophils, white blood cells that are associated with infection with worms that penetrate into the body. The organism most commonly causing eosinophilic meningitis is a rat lung worm called angiostrongylus cantonensis.