With the Johnson & Johnson (JNJ) COVID vaccine receiving Food and Drug Administration (FDA) emergency authorization for use on Feb. 27, the drugmaker has already begun shipping doses of the vaccine.

CEO Alex Gorsky told NBC’s “Today” on Monday that the vaccine was “on trucks as we’re talking,” with Americans expected to begin getting inoculated with the shot within the next day or two.

“We’re shipping 4 million literally as we speak,” Gorsky said. “Within the next 24 to 48 hours, Americans should start receiving shots in arms.”

Senior Biden Administration officials said on Sunday that healthcare providers will begin receiving the Johnson & Johnson vaccine on Tuesday, with the first 3.9 million doses distributed, CNBC reported. This is the company’s entire stockpile of vaccines, with a total of 16 million more doses to come by the end of March, according to the news outlet.

Gorsky told “Today” that as many 100 million shots will be distributed by June, with a billion doses supplied by the end of 2021.

President Biden said in a statement about the Johnson & Johnson vaccine authorization, “This is exciting news for all Americans, and an encouraging development in our efforts to bring an end to the crisis.”

Johnson & Johnson’s COVID vaccine was approved as a single-dose shot, in comparison to the Pfizer-BioNTech and Moderna vaccines, which require two doses spaced weeks apart for maximum protection of up to 95%. The Johnson & Johnson vaccine has a 66% efficacy in one dose and was shown to have an 85% success rate against severe disease and 100% effectiveness against COVID hospitalizations and death.

Johnson & Johnson is continuing its study of the COVID vaccine to determine if a second dose of the drug would be effective, NBC reported. Gorsky told "Today," the company is also beginning studies on the safety of the vaccine for pregnant women and children over the age of 12.

Shares of Johnson & Johnson were trading at $160.27 as of 10:27 a.m. EST on Monday, up $1.81 or 1.15%.

The United States has given emergency authorization to Johnson & Johnson's Covid vaccine Johnson & Johnson's COVID vaccine. Photo: AFP / JUSTIN TALLIS