The US Food and Drug Administration has approved Johnson & Johnson's coronavirus vaccine for emergency use. The FDA said on Saturday, the single-shot vaccine offered strong protection against serious illness, hospitalizations, and death.

According to a study that spanned across three continents, the jab is seen to be 85% effective against the most severe cases of COVID. The vaccine is seen to be effective against South African Variant, which is seen to be the most delightful part of this jab.

“The authorisation of this vaccine expands the availability of vaccines, the best medical prevention method for COVID-19, to help us in the fight against this pandemic, which has claimed over half a million lives in the United States,” FDA director Janet Woodcock said.

Johnson & Johnson is expected to deliver 20 million shots by the end of March. It will be delivering 100 million doses by mid-year.

Apart from being a single-shot vaccine, it is also easy to store. Unlike other US-based vaccines, Johnson & Johnson's jab does not require a special deep freeze to store the vaccine.

In large clinical trials, the Johnson & Johnson vaccine’s efficacy against the severe disease was 85.9 percent in the US, 81.7 percent in South Africa, and 87.6 percent in Brazil. The overall efficacy of the vaccine was seen to be 85.4% against the severe disease, while its efficacy against the moderate disease fell to 66.1% against the moderate disease.

The US president celebrated the new vaccine while he cautioned people to "not celebrate too soon."

“Things are still likely to get worse again as new variants spread. “There is light at the end of the tunnel, but we cannot let our guard down now or assume that victory is inevitable,” Mr. President said in a statement.

Johnson & Johnson's jab is the third to be green-lit in the US. Now, it seeks emergency approval in Europe and from the WHO to be distributed over the world.

Though slightly less protective than the Pfizer and Moderna vaccine, the Johnson & Johnson shot remains stable for at least three months at normal refrigerator temperatures, making it easier to vaccinate larger numbers of people, even in areas with poor transportation and storage infrastructure.