RSV cases continue to rise in the United States, but no vaccine will protect children from the virus.
According to the Centers for Disease Control and Prevention, RSV (or respiratory syncytial virus) is the leading cause of bronchiolitis and bronchiolitis in children younger than 1. It causes thousands of hospitalizations and hundreds of deaths every year.
Experts say there is no RSV vaccine available for children. This is because of a lack of interest. However, a failed trial many years ago and a difficult target protein made it difficult to develop an RSV vaccine.
According to Dr. Ofer Leviy, director of the Precision Vaccines Program at Boston Children’s Hospital, researchers have tried to develop an RSV vaccine for decades.
A Washington, D.C. pediatric hospital developed a vaccine against the virus in the 1960s and ran a clinical trial with young children. However, things quickly went wrong.
The experimental vaccine did not protect against RSV. It made children more susceptible to developing severe illnesses if they were infected. Two young children were among the victims.
Levy stated that “that was a disaster” and “it set the field back for 20 to 30 years.”
The RSV vaccine was eventually developed, but researchers failed to find much success. Dr. William Schaffner at Vanderbilt University Medical Center, an infectious disease expert, stated that the researchers did return to work.
The F protein, which is the virus’s protein used to infect human cells, is a clever target. Schaffner stated that the virus can quickly change its structure making it difficult for vaccines to be developed.
This isn’t a problem that only RSV has; it’s similar to how the spike protein in the coronavirus quickly changes, making it easier to dodge Covid vaccines. Dr. Celine Gunder, a senior fellow at KFF and an infectious disease specialist, stated that the problem is not exclusive to RSV.
Two vaccines from GlaxoSmithKline and Pfizer are effective in the late stages of clinical trials with older adults. This group is at high risk for serious disease.
Pfizer announced in August that it’s experimental RSV vaccine was almost 86% effective in preventing severe illnesses in people 60 years and older. GSK reported this month that their vaccine was approximately 83% effective for older adults.
Pfizer stated that it will expand the trial to younger age groups. However, testing all age groups down to 6 months could take many years. GSK however said that it gave up last year on developing a vaccine against RSV in children after trials showed it was not effective.
Gounder stated that there is no Operation Warp Speed for RSV. Phase 3 clinical trials require time, many patients, and money. Money can help speed up the process.
Pfizer has an ongoing RSV vaccine test in pregnant women. An interim analysis of the results indicated that the protective antibodies were passed to the babies by the mothers.
Synagis, a monoclonal anti-viral injection, is one option for protecting at-risk infants against severe RSV illness. However, the injection is not available for high-risk infants such as premature babies or babies with low birth weight.
Experts stressed the importance of taking common-sense measures to keep healthy in the absence of a vaccine. Schaffner stated that this includes washing your hands and avoiding contact with children who are sneezing or coughing.
Levy advised parents to call their pediatrician if their child feels unwell or has a fever. A child who is experiencing difficulty breathing should visit the emergency department.