An open question is how long the current Covid-19 vaccines will offer protection against the virus. Will they provide lifelong protection like some vaccines, such as polio, or seasonal, like influenza?

The United States may not need AstraZeneca’s Covid-19 vaccine, even if it wins U.S. regulatory approval, Anthony Fauci, the nation’s top infectious disease doctor told Reuters on April 1.

Pfizer Inc. and BioNTech SE said on March 10 that real-world data from Israel suggests their Covid-19 vaccine is 94 percent effective in preventing asymptomatic infections, meaning it could significantly reduce transmission.

Johnson & Johnson’s one-dose Covid-19 vaccine appeared safe and effective in trials, the U.S. Food and Drug Administration said, paving the way for approval for emergency use as soon as Feb. 26.

AstraZeneca and Oxford University’s Covid-19 vaccine is more effective when its second dose is given three months after the first, instead of six weeks, a peer-reviewed study published in The Lancet medical journal showed on Feb. 19.

Perhaps the synergy of federal spending and pharma/biotech ingenuity we witnessed during Operation Warp Speed should continue beyond the COVID-19 pandemic to address other medical crises. Turning the race for a vaccine into something like the 1889 Oklahoma land rush was a masterstroke.

South Africa delayed the distribution of the AstraZeneca-University of Oxford Covid-19 vaccine after data suggested it “provides minimal protection” against mild disease from the South African variant.

Sinovac Biotech’s Covid-19 vaccine was approved for use by the general public by China’s medical products regulator.

Oxford University and AstraZeneca’s Covid-19 vaccine showed in a study it had 76% efficacy against symptomatic infection for three months after a single dose, which increased if the second shot is delayed, backing Britain’s vaccine rollout policy.

After months of touting its efficacy to the western world, the efficacy of Russia’s Sputnik V vaccine was validated in a peer-reviewed study published in The Lancet.