In November, the pharma companies Pfizer and Moderna both announced substantial progress on a potential COVID-19 vaccine. While both vaccines showed promising results during clinical trials, questions remain for what's next and how to distribute a vaccine once it's available for public use.One major question mark concerns logistics. For example, the Pfizer vaccine needs to be kept at extremely cold temperatures while traveling through the supply chain — though that doesn't seem to be the case for Moderna's vaccine.Another worry is ensuring equitable access to an effective vaccine. Dr. Angela Shen, visiting scientist at the Children's Hospital of Philadelphia and vaccine policy expert, recently published a paper on the topic in a special cluster on COVID-19 vaccines in Health Affairs. She joins A Health Podyssey to discuss her paper, as well as the challenges and opportunities the US will face to secure equitable access to a COVID-19 vaccine.Subscribe: RSS | Apple Podcasts | Google Podcasts | Spotify | Castro | Stitcher