The nation’s vaccine rollout has hit some bumps but is now well ahead of schedule, with 100 million additional doses expected to be administered by the end of April. Despite the improvement, many barriers remain. State-level autonomy and decentralized vaccination systems have given states little direction and control over distribution, making it challenging to get the vaccine to hospitals, clinics, pharmacies, and community health centers effectively.

A new policy is in place that accelerates shipments of first doses, reversing President Trump’s earlier policies, and holds back second doses until they are needed. The decision should allow the U.S. to reach its goal of vaccinating 100 million people.

In the meantime, federal and state officials enlist regional and supermarket pharmacies to vaccinate frontline workers and eligible vulnerable populations. This is important because more than 100 counties lack a brick-and-mortar pharmacy, forcing residents to travel long distances in harsh weather to receive the vaccine.

A study finds that a COVID-19 vaccine strategy that prioritizes essential workers reduces the number of infections, hospitalizations, and deaths and also improves the likelihood of preventing cases of Long COVID compared with scenarios that don’t target this group. A similar finding suggests that a strategy of vaccinating older adults later improves their odds of preventing cases of Long COVID, but at the cost of slightly higher rates of adverse outcomes. This strategy will be critical in regions where vaccine supplies are low and the population is aging.