IF YOU ARE FULLY VACCINATED
CDC has updated its guidance for people who are fully vaccinated. See Recommendations for Fully Vaccinated People.
IMPORTANT UPDATE FOR SCHOOLS
CDC recommends schools continue to use the current COVID-19 prevention strategies for the 2020-2021 school year. Learn more
Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Getting vaccinated prevents severe illness, hospitalizations, and death. Unvaccinated people should get vaccinated and continue masking until they are fully vaccinated. With the Delta variant, this is more urgent than ever. CDC has updated guidance for fully vaccinated people based on new evidence on the Delta variant.
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.

COVID-19 Serology Surveillance

COVID-19 Serology Surveillance
Updated Mar. 11, 2021
Person typing on laptop

CDC is working with state, local, territorial, academic, and commercial partners to better understand COVID-19 in the United States. Serology tests look for antibodies in blood. If antibodies are found, that means there has been a previous infection. Antibodies are proteins that can fight off infections.

Interactive Dashboard

View our interactive dashboard highlighting detailed data for each of the 10 sites surveyed in the latest commercial laboratory seroprevalence study.