From the Introduction: "As SARS-CoV-2 [severe acute respiratory syndrome coronavirus 2], the virus that causes COVID-19 [coronavirus disease 2019], has spread widely over time, a number of new variants have been identified globally. According to the Centers for Disease Control and Prevention (CDC), 'a new virus variant has one or more mutations that differentiate it from the wild-type or predominant virus variants already circulating among the general population.' [...] Although they may occur in any part of the viral genome, changes in the genetic code for the virus part (known as the 'spike protein') that locks onto the host cell, have been noted in the SARS-CoV-2 variants of concern. These changes appear to strengthen viral attachment to the host cell, which can result in more efficient viral transmission (increased infectiousness). This type of change does not have to correlate with a change in the clinical severity of infection (virulence), although it may. [...] Given these concerns, Congress, in the American Rescue Plan Act of 2021 (H.R. 1319), appropriated $1.75 billion to CDC specifically for SARS-CoV-2 genomic sequencing and surveillance; other funding in the bill, such as for data modernization and forecasting, may also aid with variant tracking, as well as with coordination of such efforts at the federal level. CDC has also used appropriations from several prior coronavirus supplemental appropriations acts to expand such efforts. H.R. 1319 further provided funding to the Food and Drug Administration (FDA) to support, among other things, the continued evaluation of COVID-19 countermeasures, including with respect to emerging variants."
CRS In Focus, IF11789
Congressional Research Service: https://crsreports.congress.gov/