MONDAY, Jan. 4, 2021 (HealthDay News) -- As U.S. officials ramped up efforts to vaccinate more Americans, scientists around the world wrestled with whether it would make sense to delay the second doses everyone will need so more people can be vaccinated more quickly.
Because even the first shot offers some protection, there are experts who believe that the fastest way to get the pandemic under control is to give first injections as widely as possible now, The New York Times reported. By Saturday, only 4.2 million Americans had received their first dose of vaccine, though that number is likely an underestimate because of reporting lags, the newspaper noted.
Any delays in vaccinations are troubling as a more infectious variant of the coronavirus has been detected in at least 33 countries, The Times reported. While Britain has already chosen to delay second doses of the Pfizer and AstraZeneca vaccines in an effort to try and vaccinate more people, U.S. health officials are so far opposed to the idea, the newspaper said. However, one top official of Operation Warp Speed suggested yet another alternative on Sunday: Halve the dose of each shot of the Moderna vaccine to potentially double the number of people who could receive it.
Data from the Moderna trials showed that people 18 to 55 years old who received two 50-mcg doses had an "identical immune response" to the standard of two 100-mcg doses, Moncef Slaoui, M.D., explained, The Times reported. Each vaccine would still be delivered in two doses given four weeks apart. Slaoui said that Operation Warp Speed was discussing the dose-halving option with the U.S. Food and Drug Administration and Moderna. The company did not respond immediately to a request for comment, The Times reported.
Some experts argue that concentrating on first doses may save more lives than making sure half as many individuals receive both doses on schedule, The Times reported. Not everyone agrees, however: Some scientists fear the delayed-dose approach could be a huge mistake, particularly in the United States, where logistical hurdles and a patchwork approach to prioritizing who gets the first shots have slowed the vaccine campaign rollout.