AP Photo/Jay LaPrete
Pfizer and Moderna s coronavirus vaccines are very similar in terms of how they were made, and their safety and efficacy.
There may be slight differences in how they work in older populations, but experts say more data is needed before we make that conclusion.
Because Pfizer s needs to be stored at very cold temperatures, it will be distributed at larger institutions while Moderna s vaccine may be more likely to be distributed at smaller clinics and pharmacies.
As vaccine rollouts continue, and more enter the pool, experts will learn more about whether some vaccines are more effective in certain populations.