Zoonotic diseases: Part 2

In the second part of this series on zoonosis, we look at the world's most notorious zoonotic disease: rabies.

Rabies is perhaps the world’s most notorious zoonosis, and is fatal in 99% of cases. The disease is caused by a virus, and was historically referred to as ‘hydrophobia’, due to an infected person’s perceived panic when presented with liquids. The word ‘rabies’ comes from the Latin for ‘madness’, another perceived symptom of the disease in its final stages.

The Centers for Disease Control and Prevention (CDC) explains that the virus causes “acute encephalitis” in mammals. Rabies is most prevalent in Asia and Africa, and is almost always spread by infected dogs in these regions. However, in the US, more than 90% of rabies cases occur in wildlife, such as raccoons, skunks, bats and foxes, says the CDC. In the US, dog owners are legally obliged to vaccinate their animals against rabies, which has led to dogs making up only a small number (about 1%) of rabid animals reported every year. Rabies can be transmitted through the bite or scratch of an infected animal.

While dogs are the most common source of transmission in Africa, other animals, such as cattle and horses, can also become infected with rabies and spread the disease to other animals or humans.

Most pets get rabies from having contact with wildlife.

As rabies leads to encephalitis, which is the inflammation of the brain and spinal cord, the later stages of the disease present with many neurological symptoms, such as hydrophobia, paralysis, hallucinations, delirium and insomnia.

ANIMALS