Among the greatest challenges for public health officials as they try to slow the spread of COVID-19 are the supplies and effectiveness of vaccines. Currently, two have been approved for use. The Moderna vaccine and the Pfizer-BioNTech vaccine have been approved by the FDA for use for the general population of adults in America.
The two vaccines are different in terms of effectiveness, although the difference is small, and the amount of time between the first and second doses. According to the CDC, three other vaccines are in Phase 3 clinical trials, and could be added to the U.S. vaccine arsenal soon. The FDA just gave one of them a green light for distribution.
New vaccines could not come soon enough. The pace at which confirmed COVID-19 cases rise in the U.S. has tapered from over 200,000 a day to an average of under 100,000. Nevertheless, the confirmed case count is 28,325,091, about 25% of the world’s total. And, some scientists and medical experts think this figure is far too low because of poor testing and asymptomatic carriers.
Two forces will likely cause the acceleration or deceleration of new COVID-19 cases over the next few months. One is vaccination of as many people as possible. Today, only 13% of the adult population in the U.S. has received at least one dose. Only about 5% have received the recommended two shots. Vaccination rates have been slow, and in some states few doses are available at all. President Biden says the federal government has contracted for 200 million new doses, but all of those will not be delivered before the end of July.
As vaccination rates limp along, three new variants have reached America–from Brazil, South Africa, and the U.K. One of these variants from Great Britain known as B.1.1.7 strain, is more easily transmitted. It spreads so quickly that scientists believe it may be the most prevalent strain in the country by the end of March. An aggressive variant could cause another surge.