The new director of the Centers for Disease Control says officials have “scaled up” their surveillance of new coronavirus variants in the United States.

CDC Director Rochelle Walensky told ABC’s “Good Morning America” that previously “there has not been a public health infrastructure” to track such variants. Also, there weren’t resources to do “mass sequencing” of the virus across the country. She noted the coronavirus aid plan pushed by the Biden Administration includes funds to improve such tracing.

However, Walensky says it was “concerning” the two South Carolina individuals who were diagnosed with the more virulent strain first identified in South Africa didn’t know each other or travel there, so the “presumption” is there’s “community spread of this strain.”