CDC's national genomic surveillance program identifies new and emerging SARS-CoV-2 variants to determine implications for COVID-19 diagnostics, treatments, and vaccines authorized for use in the United States. Monitoring the spread of emerging variants in the United States relies on widespread, rapid sequencing. To accelerate sequencing in the United States, CDC contracted with commercial diagnostic laboratories along with partnering with the Association of Public Health Laboratories (APHL). CDC's collaborative approach with these organizations implemented the National SARS-CoV-2 Strain Surveillance (NS3) program to provide a comprehensive and population-based US surveillance system.

Based on these data, sequences with similar genetic changes associated with important epidemiological and biological events are grouped into lineages. A viral lineage is a group of viruses defined by a founding variant and its descendants. The proportion of lineages circulating in the United Stated are tracked and characterized to determine if they are considered variants of high consequence (VOHC), variants of concern (VOC), or variants of interest (VOI). These data, along with data from many other sources, are used to inform national and state public health actions related to variants.

Pregnant women with COVID-19, United States, January 22, 2020 - May 31, 2021 -- Pregnant women with COVID-19 by age, United States, January 22, 2020 - May 31, 2021 -- Pregnant women with COVID-19 by race/ethnicity, United States, January 22, 2020 - May 31, 2021 -- Pregnant Women with COVID-19 who were hospitalized, United States, January 22, 2027 – May 31, 2021 -- Pregnant women with COVID-19 admitted to the ICU, who required invasive ventilation, or who required ECMO, United States, January 22, 2020 – May 31, 2021 -- Data Table for COVID-19 during Pregnancy.