Nigeria, Feb. 24 -- The one-shot coronavirus vaccine made by Johnson & Johnson provides strong protection against severe illness and death from COVID-19 and may reduce the spread of the virus by vaccinated people, according to an analysis posted online by the the U.S. Food and Drug Administration (FDA) on Wednesday.

The vaccine had a 72 per cent overall efficacy rate in the United States and 64 per cent in South Africa, where a highly contagious variant emerged last year. The efficacy in South Africa was seven points higher than earlier data released by the company.

The vaccine also showed 86 per cent efficacy against severe forms of COVID-19 in the United States, and 82 per cent against the severe disease in South Africa. That means th...