Middle East Respiratory Syndrome (MERS) is a mystery virus which has claimed an increasing number of lives in Saudi Arabia, where it has spread to at least five cities. The coronavirus is from the same family of viruses as the common cold and begins with a flu-like fever and cough but can lead to shortness of breath and pneumonia. There is no cure or vaccine for Mers, and although not necessarily fatal, health experts estimate about a third of those who catch the virus die. Virologists recommend urgent campaign to improve hospital hygiene, as the bad conditions might be fuelling the epidemic, and encourage people to wear face masks which might help curb the number of new infections. Since September 2012 there have been 126 fatal victims of Mers and more than 463 have been infected. (May 2014)