RSV was discovered in 1956. Here’s why we can’t rush a COVID-19 vaccine | AAMC
Respiratory syncytial virus (RSV): This pervasive respiratory virus has proven resistant to vaccination. Children treated with one vaccine in the 1960s developed an enhanced form of the disease, suffering high fever, bronchopneumonia, and wheezing. Many were hospitalized and two died.
“That set the field back years,” Poland said, as researchers and manufacturers “were afraid” to try again.
Researchers have since tried but still not developed an RSV vaccine for public use, according to the CDC. Babies at particularly high risk for RSV are sometimes injected with an antibody to help fight off infection.
I don't grasp the Canadian government's Overview of the respiratory syncytial virus vaccine candidate pipeline in Canada, CCDR 46(4). E.g. so what if "amino acids do vary in prefusion specific epitopes"?
Challenges to RSV vaccine development
Antigen diversity
A successful vaccine candidate will account for the diversity of antigens presented by RSV in the form of the structural variability of the proteins on the surface of the virus. The protective, neutralizing antibody response to RSV is dominated by antibodies targeting the prefusion F protein on the surface of RSVFootnote 17Footnote 18. Although the genetic sequence of F does not vary substantially between strains of RSV [89% of its sequence is identical in both A and B strainsFootnote 19], amino acids do vary in prefusion specific epitopes [bolding mine]. As new products are authorized and make it into broad usage, it will be critical to understand the sero-epidemiological responses at a population level to understand whether prefusion or postfusion antibodies are dominant responses, and whether these demonstrate equivalent protection against both RSV type A and B.
RSV infection dampens the immune response
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There are no clear correlates of protection
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