Bats and health

Bats have developed a poor reputation as being the main transmitters of rabies, and this is one of the reasons that people fear them. The percentage of bats that have rabies has been over-estimated in North America (5-10%) when samples were taken primarily from sick or dead bats. When normal populations of bats are sampled randomly, less than 0.1% of bats tested positive for rabies. There are two forms of rabies – dumb and furious (aggressive). The dumb form where the animal crawls into a corner and dies is far more common in bats.

Contracting rabies from a bat is extremely rare. Since 1970, five people have died from rabies in Canada and four of these deaths followed exposure to bats. Rabies is a serious illness that can be fatal. Bats should not be feared, but caution should be taken.

  • Never handle bats
  • Beware of bats that act strangely, such as flying during the day
  • If you are bitten or scratched by a bat, seek medical attention immediately – the vaccine is excellent (5 small injections in the arm, not shots in the stomach like it used to be decades ago)

You can find out more about bats and rabies here:

Another disease that can be transmitted by bats is histoplasmosis, a disease of the lungs. The fungal spores can be transmitted through bat guano although the primary sources of the disease are from the droppings of starlings, pigeons and poultry. The disease is most common in the tropics or other humid environments and, in Canada, is thought to be primarily limited to central Canada, however a cluster of cases was detected in Alberta in 2011. Most people who contract the disease have few if any symptoms or problems, but some people can develop serious respiratory conditions. To be safe, avoid breathing in dust in areas where there are bat droppings. This can be accomplished by:

  • Use a respiratory mask that filters to 2 microns when cleaning up bat guano
  • Dampen bat droppings before cleaning them up
  • Seal droppings in a plastic bag for disposal
  • Clean surface wtih a dilute bleach solution (1 part bleach to 20 parts water)

Despite these warnings, bats are an extremely low health risk. There are more deaths annually from dogs and bee stings than from bats. Statistically, having an occupied bat-house in your yard is safer than owning a dog or planting flowers!

For more information on bats and health, see: BCI Living Safely with Bats