Severe acute respiratory syndrome (SARS): an old virus jumping into a new host or a new creation?

In recent times, newly emerging infectious diseases and their causative agents have become the focus of intense investigations by medical researchers and microbiologists, particularly virologists, since many of the causative organisms are viruses. One such disease which has created so much fear world wide is severe acute respiratory syndrome (SARS). Infection with a novel corona virus has been implicated as a possible cause of SARS.Epidemiological and laboratory investigations of SARS are ongoing. WHO estimates that SARS is fatal in around 4% of cases, usually where the person has an underlying condition such as diabetes or heart disease or has a weakened immune system. In 90% of the cases people seem to recover around after a week after being infected. This is about the same mortality rate as in other diseases such as West Nile virus infection. There are currently no antiviral drugs shown to be consistently successful in treating SARS or any corona virus infection, nor anyvaccine against SARS.