The director of the Maine Center for Disease Control and Prevention says the Moderna vaccine for the coronavirus that showed promise in an ongoing study would benefit rural parts of the state in terms of equitable distribution.

According to preliminary data, the experimental vaccine appears to be 94.5% effective. Pfizer announced last week that it’s competitor vaccine is 90% effective.

A key difference between the two is that only Pfizer’s needs to be kept in ultra-cold storage. Maine CDC director Dr. Nirav Shah said Monday that’s significant in Maine, one of the most rural states in the country and a place where distribution could be a challenge in many remote corners.

Coronavirus cases in the state have been rising recently.