Years from now, when we look back on today’s vaccine development scene, we might say it was almost as consequential as the transition from variolation to vaccination. Variolation, an ancient method, involved the use of infectious material from a person with smallpox to inoculate others against the disease. Dried and powdered material from pus or scabs would be blown up the nose or jabbed beneath their skin. Although variolation had a fatality risk as high as 3%, as well the potential to contribute to the spread of smallpox and other diseases, no better protection was available, not until it was overtaken by vaccination in the 19th century.
Vaccination made inoculation far safer and far more effective. Also, it came to be used against a widening array of diseases. Analogous improvements are now promised by advanced vaccine technologies. Some of these technologies—such as mRNA-based technologies—are breaking new ground. Others are updated versions of established technologies.