SARS is a coronavirus.
Coronaviruses are well known for their ability to mutate and change to have the ability to affect humans. Most coronaviruses come from animals. With peoples ability to travel worldwide with ease, the lack of proper handwashing and understanding of hand hygiene will always keep the doors open for a new pandemic, but because SARS is KNOWN to humans, we have a better chance of containing it.
In the news (sept 2012) is talk of a new coronavirus in the middle east, onyl two people contaminated so far, but there is concern of it being able to grow bigger, particularly with mecca coming. This virus could become pandemic, because we have not seen it before and don't know much of it.
Washing your hands properly is very important.