What health risks do bats in the attic cause?

Bats play a beneficial role in the ecosystem. They are natural pest regulators that help keep insect populations in check. However, for humans, bats pose more threats than benefits. If a colony of bats decides to roost in your attic, there is every chance that they will keep returning as bats are territorial. Even if they go to another location, they can still find their way back to your attic. 

Bats are nocturnal animals, spending most of their nights hunting and eating and the day time sleeping. This makes their presence in the attic sometimes undetectable. Their activities in the attic can cause substantial damage to the house or worse, cause serious illness in humans and pets. Some diseases are transmitted by bats that cause serious health issues in humans and pets. Some of them are listed below.


This is a disease which is transmitted from bats to humans through the droppings of the bat. The disease is caused by the fungus Histoplasma capsulatum. If the droppings of bats are mistakenly ingested by humans or pets, they can contract this airborne fungus disease. Although the incidence of histoplasmosis transmission in humans is not thought to be high, a significant number of droppings are needed to cause an infection. However, it has been found that fresh droppings of bats found in the attic can contain the fungus and humans can contract it even if it never touches the soil. 

Fungal spores are carried in the air once the bat excretes the droppings and the fungus can be inhaled by unsuspecting animals or pets. Although the infected person can sometimes be asymptomatic, sometimes the symptoms can be a minor illness which resembles influenza or it could develop into a high fever, pneumonia, abnormalities in blood and even death on other occasions. It is most deadly in people with a compromised immune system. The disease can spread from the lungs to other parts of the body and even cause skin lesions in a few people.

Health Problems Caused by Bats


Cryptococcosis is a fungi infection caused by the inhalation of the fungus Cryptococcus neoformans. The fungus is usually found in the droppings of bats and can accumulate over time in attics, basements, and other roosting sites of bats. Like histoplasmosis, the infection ensuing from Cryptococcosis can be mild to life threatening. A mild infection can often be without symptoms. However, in immunocompromised persons, it may be life threatening and these sets of people are more susceptible to the infection. 

Health Problems Caused by Bats

The infection can begin in the lungs and then gradually spread to other parts of the body, often affecting the central nervous system. This form of infection can be fatal if left untreated. Another form of the fungi infection may cause acne-like skin ulcers. This infection is dangerous because it can be easily contracted and even old and dry bat droppings can still carry the infection.


This is a much rarer disease transmitted by bat droppings. This infection is mostly mild in humans however on rare occasions, serious illnesses like pneumonia may occur.


Rabies is perhaps one of the dreaded diseases that can be transferred to man by wild animals. It is a dangerous disease that has no cure once a person has begun to show symptoms. Bats have been known to carry the rabies virus time and again. A bite from a bat carrying the rabies virus can infect a human or a pet. If bitten or scratched by a bat, it is important to visit the clinic and report the case immediately so shots of anti-rabies may be administered. Bats are simply not carriers of the rabies virus alone; they can also be infected by it. Bats infected by the rabies virus will have a window period of about a few weeks to about 6 months once the infection has matured, they can behave erratically for about 10 days. They may be seen flying outside during the day time or attacking humans and pets. It is during this active stage that they may bite humans or other animals and transmit the virus. In the later stages of the disease, the bat becomes paralyzed and eventually dies. 

In conclusion, if you come across a bat, it is best to avoid it as it may be carrying some diseases which it can transmit to you. If you notice signs of bat activity in your attic, it is best to report it to a wildlife management company and refrain from visiting the attic until they come to handle
the situation.