Saudi men walk to the King Fahad hospital in the city of Hofuf on Sunday. In eastern Saudi Arabia, where outbreaks of the MERS virus have been concentrated, people have resumed their habits of shaking hands and kissing. Fayez Nureldine/AFP/Getty Images hide caption
A railway worker wearing protective clothing to ward off the SARS virus controls a line of travelers as they wait to enter Beijing's West Railway Station Tuesday in 2003. Greg Baker/AP hide caption
Different types of coronaviruses can cause a simple cold or a deadly respiratory illness, such as SARS. BSIP/UIG via Getty Images hide caption