In 1966, the first vaccine for Respiratory Syncytial Virus (RSV), a formalin-inactivated RSV vaccine, was administered to U.S. infants and children participating in four clinical trials. The vaccinated children were subsequently exposed to RSV in the community and those who had no antibodies against RSV infection prior to vaccination experienced more frequent and severe RSV infection, a condition known as enhanced respiratory disease. The affected infants and children presented with wheezing, bronchopneumonia and fever, with approximately 80 percent requiring hospitalization. Additionally, two toddlers who were vaccinated as infants died as a result of their enhanced illness.
As a result of the failed vaccine and harms caused to those who received this experimental vaccine, development of further vaccines to prevent RSV infection stalled for several decades. However, in recent years, several pharmaceutical companies have employed new strategies to develop a vaccine without the risk of enhanced disease.
One approach has been the development of a vaccine to target pregnant women in the hopes that maternal antibodies would be transferred to the infant and offer protection from illness. Strategies has also included the use of novel vaccine technologies such as gene-based vaccines, adjuvanted subunit vaccines, and more. RSV vaccines intended for older adults were also developed and put through clinical trials.
IMPORTANT NOTE: NVIC encourages you to become fully informed about Respiratory Syncytial Virus (RSV) and the Respiratory Syncytial Virus (RSV) vaccine by reading all sections in the Table of Contents, which contain many links and resources such as the manufacturer product information inserts, and to speak with one or more trusted health care professionals before making a vaccination decision for yourself or your child. This information is for educational purposes only and is not intended as medical advice.
