May 15, 2020 / By Erika Edwards
The race to develop a COVID-19 vaccine is on, as scientists work as quickly as they can to find a way to prevent the disease that has sickened more 4.4 million people and killed more than 300,000 worldwide.
On Friday, Dr. Francis Collins, the head of the National Institutes of Health, said the agency is planning to begin large-scale testing of several of the most promising vaccine candidates this summer. Despite such efforts, and despite statements from President Donald Trump this week, a vaccine most likely won’t be ready by the end of the year. 
However, progress has been made: Scientists at the University of Oxford posted the results of a small study conducted in rhesus macaques monkeys to the preprint server bioRxiv. The study found that the experimental vaccine successfully blocked the coronavirus in the monkeys, which are considered to be good proxies for how drugs could work in people because the monkeys share a majority of their genes with humans. Clinical trials with the Oxford vaccine are ongoing in humans.
For more on vaccine progress, NBC News spoke with Dr. Gregory Poland, director of the Mayo Clinic’s Vaccine Research Group. His team’s coronavirus vaccine is in the early, preclinical stages of development.
The conversation has been lightly edited for length and clarity.