Photo: ABC News

The Food and Drug Administration approves Johnson & Johnson’s single-dose Coronavirus vaccine.

The FDA granted emergency authorization on Saturday night to the treatment, the third vaccine for use after those of Pfizer-BioNTech and Moderna.

Both the Pfizer-BioNTech and Moderna versions require two inoculations.

The news less than a day after the House approved the Biden Administration’s $1.9 trillion American Rescue Plan, and just over 24 hours after President Joe Biden spoke at a vaccination center in winter storm-stricken Texas.

We’re not here today as Democrats or Republicans, we’re here today as Americans. The American leaders with responsibility, all of us here in this parking lot, responsibility to all the people we serve when a crisis hits our states, like the one that hit Texas, it’s not a Republican or Democrat who’s hurting, it’s our fellow Americans are hurting and it’s our job to help everyone in need.

Biden noted that the Administration is well ahead of its goal of 100 million vaccinations in 100 days, stepping up vaccine distribution by 70% with 12 million weekly inoculations.

The US death toll reached 511,994 on Saturday, a rise of 2,176 on 24 hours. Confirmed cases are 28,554,465, an increase of 78,262.

The authorization of the Johnson & Johnson vaccine eases concerns over supply as inoculations escalate. While only a few million doses will be shipped to states in the next few days, production will surge to 20 million doses by the end of March and 100 million by June 30.

However, the single-dose treatment has a lower efficacy rate than PfizerBioNTech and Moderna’s of about 95%. In clinical trials, the Johnson & Johnson success has been 66% overall and 72 percent in the US in prevention of moderate to severe cases of Covid-19.

The Pfizer-BioNTech and Moderna vaccines were tested well before the emergence of Coronavirus variants, including in the UK and South Africa, which may affect the efficacy of inoculations.

The Johnson & Johnson vaccine use a harmless cold virus to deliver a gene encoding the spike protein of the virus. The Pfizer-BioNTech and Moderna vaccines use a new technique, delivering the genetic material of messenger RNA to build the spiky protein.