Nebraska could get its first doses of drug-maker Johnson & Johnson’s new coronavirus vaccine as early as this week, Gov. Pete Ricketts said Monday.

Ricketts said the state has been allowed to order up 15,000 doses, but state officials don’t yet know how much they’ll get.

The announcement came days after the U.S. Food and Drug Administration approved the vaccine, clearing the way for a third shot that’s shown to be effective. Unlike the vaccines from manufacturers Pfizer and Moderna, which require two doses to provide full immunity, the Johnson & Johnson vaccine can be delivered in one shot.

Ricketts said the state also expects to get 18,720 Pfizer doses and 17,000 Moderna doses this week. He said he was told on a recent call between governors and the White House that the Johnson & Johnson supplies may be inconsistent for the first few weeks of the rollout.

“We may be allowed to order 15,000 this week, but may not be able to get that many in weeks two and three,” he said at a coronavirus news conference.

Ricketts said residents who go to a clinic to get vaccinated will only be able to choose the vaccine that’s available on site, at least for now. He said the newly approved Johnson & Johnson won’t change the state’s plans to focus almost entirely on residents who are at least 65 years old, the demographic that has been most likely to die from the virus in Nebraska.

But he said the greater flexibility of the one-dose vaccine could be helpful in rural areas or with certain groups that are harder to reach for a follow-up shot.

Nebraska has confirmed 200,946 virus cases and 2,082 deaths since the pandemic began, according to the state’s online tracking portal. Roughly 83% of those who have died were 65 or older.

The number of new, known cases and the number of people hospitalized with the virus has continued to trend downward since the record highs set in mid-November.