Introduction to Week 3

There are diseases that produce great fear because of the difficulty of stopping the chain of transmission. Among all them, we have chosen rabies as illustrative of viral diseases that are transmitted by wounds in the skin, specifically, by bites. Besides humans, rabies also affects multiple animal species. This is known by the term of zoonosis, and it is a word that you should remember because we will use frequently along the course. It is greatly feared because of the terrible symptoms that accompany it, that once they appear, they lead inevitably to death. Rabies is the typical disease that affects multiple animal species. Besides dogs and cats, there are many wild species that play an important role in maintaining the infection.

Bats, that have a big relevance in South America, add to the problem. This makes the complete elimination of rabies from a specific region very difficult (this is known as “eradication”), as the more species that a virus affects, the more difficult it is to eradicate. To date around 200 zoonoses have been described, but the number keeps on increasing, because most emerging diseases are zoonoses. Join us this week and you will learn also about other zoonoses associated with high mortality in people, such as Nipah, Hendra, and Ebola diseases.