As per usual, the annual US rabies state-of-the-union has been published in the Journal of the American Veterinary Medical Association (Ma et al. 2023). It’s the same general information every year, but always a good reminder of the ongoing challenges with rabies here in North America.
Here are some highlights from the animal-related statistics:
- 3663 rabid animals were identified in 54 US jurisdictions in 2021.
- Cases included the typical mix of rabies virus variants (strains). See the map below for details on the geographic distribution of the different variants.
- Most affected animals were wildlife. Cases are always going to be significantly underestimated when wildlife are involved, since we only see and test a fraction of those animals.
- The number of rabid wildlife was down 18% from 2020. I don’t put a lot of stock in a result like that, since testing patterns can have a huge impact on the numbers. Rabies in wildlife isn’t going away.
- Rabid bats were found everywhere but Alaska, Hawaii and Puerto Rico.
- Raccoons were the 2nd most common species affected (if we consider all the bat spceies together). Most rabid raccoons were in the northeast, where raccoon rabies has been a problem for a while.
- Skunks were the next most commonly infected species, followed by foxes. All those species have their own rabies virus variant(s) and are considered rabies reservoir species.
- Domestic animals were less commonly affected, but the consequences of infection in a domestic animal can be much greater because of the degree of exposure to humans and other domestic animals.
- 216 rabid cats were identified, mainly from Pennsylvania, Texas, New York, Virginia, Maryland, Georgia and New Jersey. There were 36 rabid dogs detected, over half of which came from Puerto Rico, Texas, Georgia and South Carolina. One dog was imported from Azerbaijan and was infected with a rabies virus strain found there.
- Other domestic species affected included cattle (40), horses (17), a mule and a goat.
Here are some of the human-related statistics:
- Five people were diagnosed with rabies in the US in 2021. They all died.
- Four were infected with bat rabies variants, and infection occurred as a result of direct contact with bats. One person had a canine rabies virus variant that is found in the Philippines, and was infected as a result of bites from a dog while visiting that country.
- Only 1 person sought post-exposure prophylaxis (PEP) to prevent rabies. Normally, PEP is almost 100% effective. The person who developed rabies despite PEP was a noteworthy event that was previously reported, and it was likely due to a previously unrecognized immune disorder.
As in the past, the report also includes quick blurbs about rabies in Canada and Mexico:
- Still lots of wildlife rabies, with bats leading the way, followed by skunks and foxes (now that Ontario’s raccoon rabies situation is more under control).
- Domestic animals that were infected included 2 cattle, 1 goat, 1 llama, 2 cats and 5 dogs. The imported dog that developed rabies that we’ve talked about here before is on top of that.
- There were no human cases of rabies in Canada in 2021.
- There’s continued surveillance for canine rabies, since Mexico has eradicated that rabies virus variant (last case in 2016). No canine rabies variant cases were found.
- Two rabid kittens were identified, along with 67 domestic livestock with rabies.
- As in Canada, there were no human cases of rabies in Mexico in 2021.