More Babies Seriously Sick With RSV Virus


A highly contagious virus is running rampant in the U.S. this year (1999) and is sending twice as many babies to the hospital as had been anticipated. Parents and physicians are being cautioned to be on the watch for breathing difficulties in young children who are most at risk. The virus is commonly known as RSV, for respiratory syncytial virus.

Children at high risk for RSV infection include babies under 6 months of age, particularly twins and other multiple-birth babies, and premature babies. Their susceptibility to RSV is believed to reflect the fact that their lungs may not be as fully developed and as mature as those of single babies who were born at full term. Children with lung or heart problems and those with a weakened immune system are also at added risk for RSV.

Most Common Cause Of Pneumonia In Infants

RSV is the single most common and most important cause of deep lung infection (lower respiratory tract disease) in infants and young children in the world. The virus is highly contagious. In temperate climates, infections with RSV primarily occur during yearly outbreaks that traditionally peak during the winter months, although this pattern of occurrence may be changing. RSV outbreaks were detected throughout the entire period from July 1998 to June 1999 in the United States according to the Center for Disease Control and Prevention (CDC).

As a rule, RSV just causes a common cold and after a few days goes away. But it can cause far more serious problems including overwhelming pneumonia. Lung infections with RSV can leave permanent lung damage and even lead to death.

New Drug Is Artificial Antibody Against RSV

A new drug for RSV is palivizumab (Synagis). Synagis is a monoclonal antibody manufactured in a laboratory using recombinant DNA technology. It acts in the same way as a natural antibody of the human immune system, attaching to the RSV and neutralizing it before it can begin making copies of itself. It is designed to be given to small children and other persons at high risk for poor outcomes when they are infected with RSV.

One downside of Synagis (palivizumab) is that it is a monthly shot that has to be given throughout the RSV season. A new regional U.S. RSV reporting system should be useful in knowing when the RSV season is taking place in a particular area of the country.

Another downside is that Synagis does not come cheap. It costs $1,000 an injection. The manufacturer (MedImmune) has stated that the high cost of the drug is due to the costs incurred in genetically engineering and producing the product and in testing the drug to ensure that it is safe. The costs of treating the children are covered by most insurance companies and by Medicaid.


Parents and others who come in contact with babies are advised to wash their hands carefully with soap and warm water before and after touching a baby. Visits to babies by people with colds are to be discouraged. Colds can transmit RSV. Babies are best kept away from crowds for the same reason. Parents and other child-caregivers should be alert to wheezing and other breathing problems, including flaring of the nostrils and grunting, as well as to feeding problems the baby is having. (It is hard to feed if you are fighting for breath!)

Reference: Morbidity and Mortality Weekly Report 1999;48:1104- 1115.