The one-dose COVID-19 vaccine is close to getting the US’s approval as it has appeared safe and effective in trials.

The US Food and Drug Administration (FDA), paved the way for its approval for emergency use as soon as this week.

The vaccine has been proven lesser effective compared to the other US-based vaccines. The 66% effective vaccine was seen as 100% effective at stopping hospitalization after 28 days compared with 85% at 14 days.

The new data provided by J&J shows that the vaccine is proven to be 64% effective to stop moderate to severe cases of COVID 19 after 28 days in thousands of trial participants in South Africa.

There have been worries in South Africa as the new variant has swept the country and the vaccine from AstraZeneca was found almost ineffective.

A member of the FDA and the director of the Vaccine Education Center at the Children's Hospital in Philadelphia said that the data in South Africa was most encouraging to him.

The single-shot vaccine can be stored in the refrigerator in contrast to Pfizer and Moderna which needed two doses and a very cold temperature to be stored.

FDA will make its recommendation on Friday.