ARCHIVED WEBPAGE: This web page is available for historical purposes. CDC is no longer updating this web page and it may not reflect CDC's current COVID-19 guidance. For the latest information, visit CDC's COVID-19 home page.

Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
To maximize protection from the Delta variant and prevent possibly spreading it to others, get vaccinated as soon as you can and wear a mask indoors in public if you are in an area of substantial or high transmission.
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.

Data Visualization

Data Visualization
Updated Feb. 16, 2021

COVID-NET

March 1, – November 28, 2020

Weekly COVID-19-associated hospitalization rates are at their highest since the beginning of the pandemic.

Additional COVID-NET hospitalization data, including rates for different age groups and by surveillance site, are available on the COVID-NET interactive data page.

COVID Net Hospitalizations 12-14-2020

View previous graphics from COVID-NET

COVIDView

Additional COVIDView surveillance data for U.S. COVID-19 activity are available on the COVIDView page.

View previous graphics from COVIDView

MMWR Reports

February 10, 2021

Maximizing Fit for Cloth and Medical Procedure Masks to Improve Performance and Reduce SARS-CoV-2 Transmission and Exposure, 2021

CDC conducted experiments to assess two ways of improving the fit of medical procedure masks: fitting a cloth mask over a medical procedure mask, and knotting the ear loops of a medical procedure mask and then tucking in and flattening the extra material close to the face. Each modification substantially improved source control and reduced wearer exposure.

Read the full report.

Data Visualization MMWR February 10 2021

February 5, 2021

Sexual Orientation Disparities in Risk Factors for Adverse COVID-19–Related Outcomes, by Race/Ethnicity — Behavioral Risk Factor Surveillance System, United States, 2017–2019

Sexual minority persons in the United States have higher self-reported prevalences of several underlying health conditions associated with severe outcomes from COVID-19 than do heterosexual persons, both in the overall population and among racial/ethnic minority groups.

Read the full report.

Data Visualization MMWR February 5 2021

February 5, 2021

Observed Face Mask Use at Six Universities — United States, September–November 2020

During September–November 2020, mask use was directly observed at six universities with mask mandates. Among persons observed indoors, 91.7% wore masks correctly, varying by mask type, from 96.8% for N95-type masks and 92.2% for cloth masks to 78.9% for bandanas, scarves, and similar face coverings.

Read the full report.

COVID-19 rapid tests are inexpensive and fast but sometimes give incorrect results

January 29, 2021

Impact of COVID-19 on Cervical Cancer Screening Rates Among Women Aged 21–65 Years in a Large Integrated Health Care System — Southern California, January 1–September 30, 2019, and January 1–September 30, 2020

During California’s stay-at-home order, cervical cancer screening rates among approximately 1.5 million women in the Kaiser Permanente Southern California (KPSC) network decreased approximately 80% compared with baseline. The decrease was similar across all racial/ethnic groups of KPSC and returned to near normal after reopening.

Read the full report.

MMWR Jan 29 2021

January 26, 2021

COVID-19 Cases and Transmission in 17 K–12 Schools — Wood County, Wisconsin, August 31–November 29, 2020

Among 17 rural Wisconsin schools, reported student mask-wearing was high, and the COVID-19 incidence among students and staff members was lower than in the county overall (3,453 versus 5,466 per 100,000). Among 191 cases identified in students and staff members, only seven (3.7%) cases, all among students, were linked to in-school spread.

Read the full report.

COVID-19 Cases and Transmission in K-12 Schools

January 25, 2021

Implementation and Evolution of Mitigation Measures, Testing, and Contact Tracing in the National Football League, August 9–November 21, 2020

The National Football League observed SARS-CoV-2 transmission after <15 minutes of cumulative interaction, leading to a revised definition of a high-risk contact that evaluated mask use and ventilation in addition to duration and proximity of interaction. Intensive mitigation protocols effectively reduced close interactions.

Read the full report.

MMWR Report Jan 25 2021

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Other Publications

July 23, 2020

Multisystem Inflammatory Syndrome in U.S. Children and Adolescents

A recently published study identified 186 cases of multisystem inflammatory syndrome in children (MIS-C) across pediatric health centers in 26 states from March through May, 2020. Read the study online: https://www.nejm.org/doi/full/10.1056/NEJMoa2021680external iconexternal icon

July 6, 2020

What COVID-19 Seroprevalence Surveys Can Tell Us

Seroprevalence surveys are investigations that involve the use of serology test (also known as antibody tests) to better understand how many SARS-CoV-2 infections have occurred at different points in time, in different locations, and in different populations in the United States.
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July 1, 2020

Percentage of Population Positive for SARS-CoV-2 Antibodies in Samples from Areas in 6 States

​CDC is partnering with commercial laboratories to conduct a large-scale geographic seroprevalence survey that has tested de-identified clinical blood specimens from 6 sites. Read more about this survey: Commercial Laboratory Seroprevalence Surveys

Percentage of Population Positive for SARS-CoV-2 Antibodies in Samples from Areas in 6 States

Archived COVIDView Graphics

Archived COVID-NET Graphics

Archived MMWR Report Graphics