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Bats are getting a lot of attention around here following the recent death of a person in Ontario from rabies. The infection was “suspected to have been acquired from direct contact with a bat…” Most rabies deaths that occur in North America nowadays are due to transmission from bats, but all too often the risk of contact with a bat isn’t recognized. If a person is exposed to rabies through contact with saliva from an infected bat and post-exposure treatment isn’t given promptly, the outcome can be tragic.

Rabies is endemic in bats throughout North America – wherever we have bats, we have rabies. We don’t know the exact percentage of bats in the general population that are infected, but ultimately it doesn’t really matter – whether it’s 0.1%, 1%, 10% or more, it’s in all our bat populations. Any one bat could be infected (and you can’t tell just by looking at the bat, or its behaviour), and therefore any bite from a bat could transfer rabies virus to a person (or other mammal).

One of the major issues with rabies in general but especially when it comes to bats is the general public’s understanding of the risks. Bats in particular have tiny teeth (and they can move very fast!), so a little bat bite might not be noticed. Even if the bite is noticed, there’s so little trauma that a person could easily dismiss it, and wouldn’t seek care like they might for a bite from a larger mammal. But we need people to understand that even a tiny bite from a high-risk species like a bat can transmit rabies. Any contact with a bat that could have resulted in a bite needs to be investigated promptly so post-exposure treatment can be given when necessary to stop the virus before it can cause infection.

But determining the level of risk is sometimes still really hard.

  • If a bat is lying on sidewalk and you pick up (note: please never do that!) and you feel a bite: That’s clearly exposure.
  • If a bat flies into your house when you open the door, does a little tour, and then flies back out: That’s clearly not exposure.
  • The problem is the big grey area in between.

In Ontario, prior to 2008, waking up in a room with a bat was considered a potential exposure based on the premise that you could be bitten but not notice if you were a asleep. That’s the situation I ran into we had a rabid bat in our house back in 2008. Because the bat had likely been in the house for a few days (and everyone had been sleeping at some point), everyone got rabies post-exposure prophylaxis (PEP). Shortly after that, the guidelines changed based on the very low risk posed by that type of situation and the healthcare burden of the massive number of people that received PEP (unnecessarily) for that reason.

Now, there is a more complex risk assessment for bat exposures (see below), and sleeping in a room with a bat does not automatically mean PEP is indicated. If in doubt, the default is typically to give PEP, because rabies is so deadly and PEP is incredibly effective. However, it’s not indicated in most situations when a bat is in the house and there’s no evidence of direct contact. That can be tough messaging to communicate in the moment though, especially when kids are involved.

We don’t want to eradicate bats.

  • They are important parts of the ecosystem (especially for controlling insect populations!).
  • Several bat species in Ontario are actually endangered.
  • It’s not their fault they are rabies reservoirs.
  • Please beware but be kind to bats!

We can’t eliminate rabies from bats.

We can’t eliminate the risk of a bat being rabid.

  • Not all rabid bats look sick or act abnormal.
  • Bats can’t be tested for rabies while they’re still alive, because the brain needs to be sampled.

We CAN essentially eliminate the risk of rabies from bats in people with some basic measures.

A lot of that revolves around public awareness. The key points are:

  • Stay away from bats.
  • Discourage bats from roosting in buildings; seal up any tiny holes they might use to get into a building.
  • If a bat gets in your house, open as many doors and windows as you can to let it fly back out (the bat doesn’t want to be in your house either!)
  • If you do have direct contact with a bat (despite efforts to avoid it!), talk to public health to see if rabies PEP is indicated. Look closely for any marks on the skin that might indicate a bite, but don’t dismiss the possibility if you don’t see anything.
  • If you wake up and find a bat in the room, talk to public health to see if rabies PEP is indicated.
    • In either of these cases, if the bat or its remains are available, it may be possible for public health to arrange to have it tested to definitively determine if rabies is a risk. But bats should not be killed or euthanized just for testing if it’s not clearly necessary!

The most important point is recognizing there’s a rabies risk from bats and that anyone with potential contact with a bat should engage public health. Rabies is almost completely preventable if we take the right steps, but if people don’t realize the risk and know what to do, we miss the chance prevent this horrible disease.

The recent death was tragic. Hopefully some good will come from it in the form of more awareness.  

Also don’t forget that pets can also be exposed to rabies if they have direct contact with a bat! If your pet catches, plays with or otherwise touches a bat, be sure to contact your veterinarian for a risk assessment (even if your pet is currently vaccinated for rabies), in case additional action is needed to protect your pet and you!