The vaccine’s level of protection varied by region, J&J said, with the shot demonstrating 66% effectiveness overall, 72% in the United States, 66% in Latin America and 57% in South Africa, where the B.1.351 variant is rapidly spreading. However, the FDA staff documents show the vaccine was 64% effective in South Africa after about a month. The company said the vaccine prevented 100% of hospitalizations and deaths.
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JJ testing to see if adding a 2nd booster shot increases effectiveness too.
The British government plans to study whether giving the JJ vaccine first, then some other vaccine 2nd, boosts the effectiveness. They are doing this with other vaccines too, such as giving the Oxford AstraZenica vaccine 1st, then Pfizer vaccine shot 2nd, etc. You might call this “mix and match” research.
