About 20 percent of the US population received at least one Covid-19 vaccine, as the rate of inoculations in the United States increases dramatically. Here is a look at the vaccines that have been authorized by the Food and Drug Administration and where are some other vaccine candidates.
How many vaccines are authorized in the US now?
Three: from Pfizer-BioNTech, Modern and Johnson & Johnson. Pfizer was the first in December, followed by Moderna shortly thereafter; each is given in two doses with an interval of three to four weeks. The Johnson & Johnson vaccine, authorized last month, is administered in a single dose.
Is the Johnson & Johnson single injection vaccine widely available?
Not yet. When authorized on February 27, Biden government officials warned that supplies would be limited in the first month, with 3.9 million shots initially and 16 million more in late March.
Johnson & Johnson last year promised to deliver 37 million doses by the end of March and a total of 100 million by the end of June, but is still working to increase production on that scale. A recent agreement with Merck aims to increase manufacturing and packaging capacity.
President Biden said last week that the federal government would order another 100 million doses of the Johnson & Johnson injection.
Which vaccine could the FDA authorize to follow?
Novavax could apply for emergency use authorization for its dual vaccine in late April. It offers robust protection, although it was not as effective against a variant that circulated rapidly in South Africa as it was against other versions. Novavax may deliver 110 million doses by the end of June if the FDA releases the vaccine for use.
AstraZeneca, whose vaccine is authorized in more than 70 countries, has not yet reported the results of its clinical trial in the United States, nor has it applied for authorization in the United States.
The AstraZeneca vaccine, developed with the University of Oxford, encountered some problems. European countries have suspended use of it due to concerns about blood clots, although no evidence has been found of any causal link. Some people in Germany are also refusing to receive it because of its lower overall effectiveness in clinical trials, compared to other vaccines.
When can all Americans be vaccinated?
Biden said he would guide all states to expand eligibility to include all adults – about 260 million people – by May 1. No vaccine has been authorized for children yet.