RSV is an abbreviation for Respiratory Syncthial Virus - a common respiratory virus that usually causes mild, cold-like symptoms. Most people recover in a week or two, but RSV can be serious. Infants and older adults are more likely to develop a severe chest infection. In those with COPD it can lead to a flare-up (exacerbation) that might require hospitalization. There are two vaccines that are more than 80% effective in preventing RSV infection.