One way pediatricians can make kids happy is to offer them vaccines that don’t involve an “owwee.” There are currently two childhood vaccines that fit the bill: oral poliovirus vaccine (OPV), which is no longer used in the United States, and live-attenuated influenza vaccine (LAIV) — otherwise known as FluMist — that gets sprayed painlessly up the nose. Researchers have been working on a new and eagerly-awaited vaccine against respiratory syncytial virus (RSV) that will also be simple nasal squirt. RSV is an incredibly common viral infection (practically every child in the United States will have experienced a bout of this infection by the age of two), and it is potentially very dangerous, especially to very young infants.
RSV is one of the more contagious viruses that comes around the Northeast every year, usually in late October or early November, and does it’s viral thing until early spring. Pediatric Alliance’s Damien Ternullo, M.D., explained RSV’s modes of transmission in a previous PediaBlog post about bronchiolitis two seasons ago:
Similar to how other viruses (like influenza) spread, RSV spreads when an infected person coughs or sneezes out tiny respiratory droplets that contain the virus. These particles then travel to another person either directly into someone else’s eyes, nose, or mouth, or indirectly, by way of touching the infected droplets (where one touch from contaminated fingers to the eyes, nose, or mouth results in infection).
Illness with RSV usually begins as an especially severe runny nose and cough. Fever is common, and infants and toddlers who are affected are miserable and fussy, don’t eat very well, and don’t sleep well either (and neither do their parents!). The virus has a special propensity for attacking deep down the respiratory tract, affecting the smallest airways and air sacs, causing bronchiolitis and pneumonia, respectively, in some children. Children with RSV bronchiolitis typically breathe more rapidly than normal and show other signs of respiratory distress. Air squeezing through the tiny, swollen airways results in wheezing that can be heard with a stethoscope (and sometimes audibly, without one). More severe infections lead to the inability of babies and toddlers to get enough oxygen into their bodies, which is a dangerous situation. Frighteningly, infection with RSV has been associated with neonatal apnea and sudden infant death syndrome.
In the United States, according to the CDC, nearly 60,000 children under the age of five are admitted to the hospital with RSV bronchiolitis and pneumonia every year. For every child hospitalized, approximately 30 more are sick enough with the virus to require a visit to a pediatrician, other outpatient clinic, or emergency room. Globally, RSV kills tens of thousands of young children each year; in the U.S., it’s about 200. But RSV isn’t a menace to newborns and young children alone; it causes 177,000 hospitalizations and 14,000 deaths among adults older than 65 years in the U.S. every year.
This explains why pediatricians and other providers have been impatiently waiting for a new vaccine to prevent RSV infections. Maggie Fox says the National Institutes of Health and vaccine manufacturers are hard at work developing a vaccine without an “owwee”:
They made a needle-free vaccine that could be dripped into the nose. Like the needle-free FluMist flu vaccine, the idea is to stimulate immune cells in the nose and respiratory tract first, and then throughout the body, they report in the journal Science Translational Medicine.
Almost all of the babies developed a strong antibody response to the vaccine, meaning their bodies produced immune system proteins that should neutralize a virus before it could cause an infection. To protect against RSV, people also need a second immune response in cells called T-cells, and the researchers have not been able to measure that yet in the babies.
This vaccine sounds promising to those of us on the front lines of children’s health care. It can’t come soon enough.