There has recently been a lot of unreasonable worry about RSV (respiratory syncytial virus) infections again. RSV can cause bronchiolitis which is inflammation of the small airways of infants and children. Bronchiolitis causes wheezing and can be quite distressful, especially in babies with heart disease, prematurity, lung disease or other serious illness. However RSV usually causes just a runny nose and a cough, which closely resembles the cold caused by many other viruses. Also other viruses can cause bronchiolitis and wheezing. Whether just a cold or wheezing is caused by RSV, or some other virus makes no difference for the treatment or management. There is no specific treatment. Asthma medications, used to treat wheezing in older children with asthma, do not help and can add to the problem because they increase heart rate, make it difficult to rest and increase oxygen need.
Finally, everyone will get RSV at least once before their third birthday.
So why test for RSV? Good question. The American Academy of Pediatrics has published recommendations about the diagnosis and management of bronchiolitis based on the best evidence. (1) Recommendation number one is, “bronchiolitis should be diagnosed on the basis of the story and the physical exam. You should not routinely order laboratory or x-rays for diagnosis.” Recommendations 2 and 3 are, “asthma medications should not be used routinely in the management of bronchiolitis,” because of a “preponderance of harm over benefit.”
Doctors might want to test for RSV out of curiosity to see what percent of babies are infected for epidemiological purposes to monitor the seasonal burden. RSV is a winter season infection like influenza. But for any particular baby it makes no difference. It might seem harmless to test for RSV except for the pain and expense but it might also make people react inappropriately as seems to have been the case in Portsmouth recently.
Addendum to the above article first printed in the Portsmouth Daily Times April 16, 2012:
October 28, 2022
Since there was a dearth of exposure to RSV and influenza during the COVID lock downs, there will be cohort of babies and everybody else who have not built immunity and also judging from the experience of the southern hemisphere who have winter during the last season, we can expect a bad season this winter for us in the northern hemisphere