Evidence shows the new coronavirus strains have stronger transmissibility, increase hospitalizations or deaths, and reduce vaccine effectiveness.
The United States has seen an upward trend in COVID-19 cases for four consecutive weeks, as social distancing and mask mandates were lifted in some areas and more variants transmitted across the country.
The U.S. Centers for Disease Control and Prevention (CDC) announced that the current 7-day moving average of new COVID-19 cases stands at 67,530 cases, a figure which is up around 6 percentage points from the previous seven days.
Meanwhile, new COVID-19 hospitalizations also went up 7.3 percent from the previous 7-day period. As of April 10, the U.S. had recorded 20,915 infection cases of the British variant (B.1.1.7).
There were also 453 cases of the South African strain (B.1.351), and 497 cases of the Brazilian strain (P.1). In addition, two coronavirus strains first detected in California are also being closely monitored by the CDC.
The five coronavirus strains are currently classified as "variants of concern," as evidence shows that they have stronger transmissibility, increase hospitalizations or deaths, and reduce vaccine effectiveness.
The British strain is the most common coronavirus circulating in the U.S. and has been reported in all 50 states, the District of Columbia, and Puerto Rico.
Even as the country picks up its COVID-19 vaccination pace, the coronavirus variants are spreading rapidly, and health experts warn that the variant infections could potentially stall the nation's recovery from the pandemic.