Despite the fact that mRNA (messenger RNA) vaccines have been worked on and developed for decades, in the last 2 or so years, talk of mRNA vaccines has increased because both Pfizer and Moderna Covid vaccines use mRNA technology. According to ScienceNews.org, “mRNA vaccines tell our cells how to make a mimic of a viral protein” and in the case of COVID-19, the vaccine tells our cells to mimic the spike protein that coronavirus uses “to break into cells.” Because of the need for quick and effective mRNA vaccines during the pandemic, there is hope that these vaccines can get us closer to “Fighting all sorts of infections. Attacking cancer cells. Restoring specific proteins to treat genetic diseases, such as cystic fibrosis.” Currently there are several research efforts into mRNA for other things like HIV, influenza, Zika virus, and cytomegalovirus. 

https://www.sciencenews.org/article/mrna-vaccine-next-viruses-flu-hiv-zika