Massachusetts received 58,000 doses of the Johnson & Johnson coronavirus vaccine last week, the first shipment of what could be a substantial boost in vaccination efforts here and across the country.

But it’s not clear how that boost will play out or when it will start. Gov. Baker said he is not expecting any more J&J deliveries until late this month early April. And he hasn’t spelled out how Massachusetts might target the J&J vaccine given its unique advantages: it’s a single dose shot, and it can be moved around a lot — even jostled — without risking stability.

Seventy-two percent of Americans who received the J&J vaccine in trials were protected from a mild to moderate case of Covid-19, as compared to more than 90 percent for the vaccines from Moderna and Pfizer-BioNTech. The three are similar at preventing the worst outcomes: hospitalizations and death. Public health and medical experts are urging people to get any vaccine offered.

“If someone offered me any one of those three vaccines, I absolutely would be comfortable and would be very willing to take any one of those three,” said Dr. Paul Biddinger, who chairs the vaccine advisory board in Massachusetts.

In fact, you may not have a choice. Many hospitals and health centers say they’ll give patients the vaccine that’s available at the time of their appointment because managing the timing, logistics, and supply of three different vaccines is complicated enough.

Charles River Community Health, which serves 15,000 mostly low to moderate income patients at clinics in Allston-Brighton and Waltham, has been told to expect alternating deliveries of Moderna one week and J&J the next. Other health centers are getting Pfizer as well. And if patients object to the week and the vaccine they’re offered?

“We’ll attempt to educate them,” says Charles River CEO Elizabeth Browne. “If patients feel really strongly about one vaccine or the other, we’ll say, ‘We hope you can understand that we need to vaccinate as many people as we can as quickly as possible.’”

It remains unclear whether all of the state’s large-scale vaccination centers will begin receiving the J&J vaccine once supplies increase, in addition to Moderna and Pfizer. Tufts Medical Center, which began injecting J&J doses this week, is also not offering or entertaining a patient’s choice.

“That’s for a variety of reasons,” says Dr. Helen Boucher, chief of infectious diseases at Tufts. “The first and most important is that there is no reason to pick one over the other because all three are safe and effective.”

This article was first published by WBUR 90.9FM on March 5. The Reporter and WBUR share content through a media partnership.