Although the World Health Organization now classifies the B.1.617 coronavirus variant first identified in India as a "variant of concern,” it is still classified as a "variant of interest" in the United States.
Classifications of coronavirus variants in the United States may differ from the classifications made by WHO "since the importance of variants may differ by location," the US Centers for Disease Control and Prevention told CNN in an email on Tuesday.
The agency also noted that classifications could change — to escalate or deescalate — based on scientific evidence. The CDC works with the US Department of Health and Human Service' SARS-CoV-2 Interagency Group (SIG) on its classification scheme for variants.
"Since the importance of variants may differ by location, CDC, in collaboration with the SIG, is closely monitoring the emergence of the B.1.617 variant in the United States," the email said in part. "And this variant has been prioritized for characterization by the US government to better understand the potential impact on available medical countermeasures, including vaccines, therapeutics, and diagnostics."