RSV Vaccine – there still isn’t one…(yet)

Respiratory Syncytial Virus, or RSV for short, is a viral infection that causes a mild respiratory disease in many infants and toddlers and more severe disease in a few, especially in premature infants. It circulates during the winter and is quite contagious, being spread by respiratory droplets and infected surfaces to susceptible patients. Many parents have brought their infant or toddler to their doctor with symptoms of cough, congestion and wheezing, finding out that their child has what we call "bronchiolitis."" RSV is one of the largest causes of bronchiolitis. We rarely do tests to confirm which virus is causing these symptoms, so for most pediatricians RSV and bronchiolitis mean the same thing.

The most severe complication of RSV is that in very young infants (under 2 months old) and in preemies, RSV can trigger respiratory failure and apnea (cessation of breathing). These can result in hospitalization for mechanical ventilation, oxygen therapy, intravenous nutrition and often prolonged hospital stays. Weeks or months of intensive care can run up hospital bills into the hundreds of thousands of dollars. For older infants and toddlers, RSV is usually not so severe, but can occasionally lead to hospitalization for oxygen therapy alone while the disease runs its course. A lesser-known fact is that RSV also strikes older people, and causes a large number of deaths and cases of pneumonia among the elderly, especially those who live in nursing homes or other group settings. Exposure to the virus occurs when babies and children with RSV visit their elder family members, who become infected and then in turn infect their peers.

Currently, there is a preventive treatment for RSV that is fairly effective but is also very expensive and inconvenient. The medication is called Synagis – an injected synthetic antibody specifically developed to combat RSV. Unlike a vaccine, which stimulates the body’s immune system to make natural antibodies to fight off an infection, Synagis is an artificial antibody, which has to be given repeatedly because its levels start to drop soon after injections are given. The problem is that it has to be given by injection each month during RSV season, and the cost is huge: a single month’s dose can cost $1500 or more, and it is typically given for up to 5 months in a row (November through March) to patients, who must qualify for the treatment to assure insurance coverage. Also, the need to come to the doctor’s office monthly is less than ideal.

Understandably, the quest for an RSV vaccine is a large focus of pediatric research dollars, as a preventive therapy would pay off many times over in dollars saved. Several companies have clinical trials in progress seeking to develop an effective vaccine against RSV. Unfortunately, this is an old and sad story, as there have been many candidate vaccines for RSV over many years without a single viable result. The company that makes Synagis (AstraZeneca) is also seeking to improve it, so that it will last longer (and remain under patent protection). The case for a vaccine to prevent RSV is obvious – it would save lives, prevent some very expensive hospitalizations, and if given universally, would eliminate a large source of illness during the winter months among the very young. This is turn would keep kids in daycare and keep parents at work. The only losers would be pediatricians’ offices, since we would be less busy during RSV season. I for one would be happy for the decreased business!