Response

In response to case 3 of my article,1 I have had several colleagues point out that as of August 2008 the guidelines for recommending rabies postexposure prophylaxis (PEP) in Ontario have changed with regard to individuals who wake up from sleep and find a bat in their rooms. This decision was based on research published by Dr De Serres of l’Institut National de Santé Publique du Québec,2 and further details can be found on the Ontario Ministry of Health and Long-Term Care website (www.health.gov.on.ca/english/providers/pub/disease/rabies_qa.html). The province of British Columbia has also updated their rabies guidelines in a similar fashion.3

While I was aware of the Ontario changes when submitting my article for publication, I chose not to include them when discussing case 3, as they were not consistent with the most recently published national Canadian guidelines (ie, from the National Advisory Committee on Immunizations4). Furthermore, other recognized international rabies PEP guidelines (eg, from the Centres for Disease Control5 and the World Health Organization6) have yet to make such changes.

Given that management of potential rabies exposures to bats, as outlined in case 3 of my article, seems to be a somewhat gray area, Dr Casale’s point that each case needs to be assessed on an individual basis is extremely important. One should not interpret the recent guideline change in Ontario to mean that individuals who wake up in a room and find a bat have no risk of rabies exposure. Given that bats are considered high risk for transmitting rabies, a proper risk assessment for direct exposure should still take place with the assistance of local public health experts. A key question to ask is whether the individual would likely wake up from sleep if she or he felt a sharp bite or scratch. If the answer is yes, then the likelihood of direct exposure while sleeping is low. It is also important to consider whether the above likelihood would change under certain circumstances, such as if the individual in question was a child (eg, unreliable historian), was under the influence of alcohol, or was mentally challenged. A physical examination looking for bites or scratches should also be part of the assessment.

Finally, from a prevention standpoint, individuals in Canada who live in geographic areas known to have a high prevalence of bats should consider “bat proofing” their homes to reduce their chance of exposure. There are many wildlife companies available that specialize in providing such services.

• Copyright© the College of Family Physicians of Canada