
As scientists work towards a COVID-19 vaccine, they are faced with the decision of which type of vaccine to choose. Here, we review the different types of vaccines, how they work, some examples, and current COVID-19 trials in each category. For additional information on the science behind vaccine approaches for covid-19, take a look at Research!America’s COVID-19: By the Science infographic. Live-attenuated vaccines Live-attenuated vaccines use a weakened form of the germ (bacteria or virus) that causes the disease. Scientists weaken the germ by altering its genetic code to prevent the germ from rapidly replicating in human cells. This weakened form can no longer cause the disease, but the...