Researchers in Scotland have concluded that Respiratory syncytial virus, the single largest cause of lung infection in children, causes some 200,000 deaths each year.

University of Edinburgh has said that although it usually causes only mild cold-like symptoms, the virus in premature infants or those who have congenital heart disease can cause serious illness.

Data from developing countries and all the published studies on RSV were analyzed by an international team of researchers which found that more than 33.8 million children get infected with RSV each year.

It was further found by the study that 99 percent of RSV-related deaths occur in developing countries.

Dr. Harish Nair of the University of Edinburgh said in a statement, "Our greatest hope of fighting this virus is to develop a vaccine, but before we can implement an immunization program, we need to understand exactly how big a problem RSV poses."

He further added, "This is the first time we have gathered information on such a global scale and is the best estimate we have for the number of children dying each year from this preventable illness." (With Inputs from Agencies)