As the first COVID-19 vaccines are being administered across the United States—developed, tested, and approved with historic speed—countless questions have arisen about what comes next. Is one vaccine better than another? Can the United States both speed up inoculation and overcome some people's hesitance to get the shot?

Dr. Courtney Gidengil, a senior physician policy researcher in RAND's Boston office, authored a comprehensive review of vaccine safety in 2014, which is being updated now and will be released soon. She said that the size of the patient trials (over 30,000 participants in each of the Pfizer and Moderna trials) and length of follow-up to date should instill confidence, despite the newness of mRNA vaccines. Extended studies of other vaccines also show no evidence of long-term damaging effects, she said. The robust vaccine safety monitoring system that is already in place is also being expanded for the new COVID-19 vaccines.

For teens and younger children, however, vaccine trials are just getting underway. Children respond differently to COVID-19, rarely getting ill; but the rare serious reaction to the virus is a dangerous inflammatory response about a month later. Gidengil, who is also an infectious disease physician at Boston Children's Hospital, says that trials are getting underway for children as young as 12 and expects to see trials starting for those younger than 12 and pregnant women this spring.

That the initial rollout has been bumpy shouldn't be a surprise, noted Jeanne Ringel, director of RAND Heath Care's Access and Delivery Program. State public health systems have been stretched thin by the pandemic for months. Florida's approach, which is to make anyone 65 and older eligible immediately for vaccination, shows the challenges of fast mass vaccination. County officials, for instance, resorted to using commercial platforms like Eventbrite to manage reservations, and phone systems were overwhelmed by demand.

Read the full article about vaccine rollout by Robin Rauzi at RAND Corporation.