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How Rabies Works


How Do You Test an Animal for Rabies?

Rabies is a disease that affects the nervous tissues, meaning that it's not found in blood, feces or urine. As you can probably imagine, this makes it quite difficult to test animals for the virus. To complicate matters further, potential testing outlets, such as saliva, don't yield results as quickly or as accurately as brain matter. Therefore, an animal's head must be removed, post-mortem, in order to gauge its infection status accurately. For more than 40 years, this has been the only accepted rabies testing method for animals in the United States [source: CDC].

Believe it or not, if you suspect a small wild animal of having the disease, you'll often be encouraged to try and capture it yourself, especially if it's a bat. But don't worry, no one is going to expect you to wrestle with a frothing coyote or raccoon. If the offender can't be safely apprehended, Animal Control will usually attempt to capture it later. Then, it's off with the animal's head. After the creature has been decapitated, its head is placed on ice for preservation and sent to a laboratory where it can be tested.

Unvaccinated pets that have a run-in with a potentially rabid animal are either euthanized or placed under strict, isolated observance for 10 days. If the animal makes it through this probationary period without incident, it's given a clean bill of health and allowed to return to life as normal.

To help ease the wild rabies threat in the United States, some state governments have begun distributing rabies vaccine bait in highly affected areas. The bait is essentially a high-dose oral version of the vaccine. It's primarily aimed at attracting raccoons (and is safe for contact with most mammals, including dogs and people).

Even though the vast majority of rabies cases are contained in the animal kingdom, the disease still kills tens of thousands of people worldwide every year. Check out the next page to learn which animal poses the greatest danger to humans: bats or dogs.