The Biden administration will start shipping almost 4 million doses of Johnson & Johnson’s COVID-19 vaccine on Sunday after the Centers for Disease Control and Prevention formally recommended the shot for adults ages 18 and up.

CDC Director Rochelle Walensky signed off on the recommendation Sunday following a unanimous decision from an advisory panel. The CDC’s Advisory Committee on Immunization Practices voted 12-0 during an emergency meeting the same day to review J&J’s shot, which the Food and Drug Administration cleared late Saturday.

The U.S. administration will begin on Sunday to ship 3.9 million doses that are already available, with the first deliveries arriving as early as Tuesday, according to senior administration officials who held a briefing call on condition on anonymity. The shots will be shipped through every distribution channel, including to states on a per-capita basis and directly to pharmacies and community health centers, the officials said.

The company still plans to deliver a total of 20 million doses by the end of March, though those will predominantly arrive in the latter half of March, one of the officials said. J&J plans to deliver 100 million doses overall to the U.S. during the first half. Walensky in a statement called the shot “another important tool in our toolbox to equitably vaccinate as many people as possible, as quickly as possible.”

J&J rose 2.3 per cent in trading before U.S. markets opened.

J&J’s vaccine differs from those already in use -- one from Moderna Inc. and the other from partners Pfizer Inc. and BioNTech SE -- because of its one-dose regimen and its ability to be stored in a refrigerator, both of which contribute to ease of distribution and administration.

Those features may help immunizations reach some groups disproportionately affected by the pandemic, such as the homeless, rural residents, people with involved law-enforcement actions, the disabled and homebound as well as those with limited access to health care, a CDC reviewer said.

Vaccine Preferences

The administration officials all stressed the efficacy of the J&J shot and urged Americans to take whatever shot they can, as soon as it’s available. All three vaccines will be available in all communities, one official said -- a de facto assurance that the J&J shot, which is easier to transport, won’t be the only one sent to under-served communities.

Health officials may need to persuade people to take one shot from J&J rather than two doses from Pfizer-BioNTech or Moderna. A February survey found only 7 per cent of people would choose a single-dose vaccine, compared with 58 per cent who said they prefer a two-dose series, according to a presentation in the online meeting. About one in five said they would take either.

Of those who want a two-dose shot, 28 per cent said they would get a single-dose option rather than wait a month to get another one. The survey was conducted before all the data on J&J’s vaccine became available, which could affect attitudes. The administration officials said they expect some people will prefer a one-dose vaccine.

Jason Goldman, a representative of the American College of Physicians, stressed the importance of discouraging comparisons among the three available COVID-19 vaccines.

“We want to make sure that the public understands the best vaccine is the one they can get access to,” said Goldman, a liaison to the panel.

Anthony Fauci, Biden’s chief medical adviser, said Sunday that he wouldn’t hesitate to take J&J’s vaccine. Americans should take any vaccine available to them, he said in an interview on NBC’s “Meet the Press.”