3. SARS
The acronym SARS is short for Severe Acute Respiratory Syndrome, and it’s one of the worst influenza-type infections the world has ever seen. The worst outbreak we’ve had yet affected the world in the year 2003, and it quickly spread to most of the world from there (in part thanks to people who traveled to infected areas and spread the disease without realizing it).
The condition affected anyone with a compromised immunity faster and worse than it did everyone else, and the disease caused a fair amount of fatalities over the world.
Even though the worst of the SARS infection is considered to be eradicated, the condition is still on the World Health Organization’s watchlist as a pandemic due to the damage that is caused during the first outbreak and the fact that the condition is far from eradicated.
Symptoms can mirror several of the diseases on this list, including common colds and flu as well as serious varieties like swine or avian flu.