Important update: Healthcare facilities

CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more

Find the latest information:
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Recommendations for Fully Vaccinated People
COVID-19 Homepage

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.

UPDATE

The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.

UPDATE

Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

Post-COVID Conditions: CDC Science

How CDC is using science to learn more about post-COVID conditions (or long COVID)

Updated May 5, 2022

CDC is analyzing healthcare data, partnering with clinicians, and working with researchers to learn more about post-COVID conditions (Long COVID).

Post-COVID conditions (PCC, or Long COVID) are a wide range of new, returning, or ongoing health problems people can experience four or more weeks after first being infected with the virus that causes COVID-19.

Learn more about post-COVID conditions (Long COVID).

What CDC Is Doing to Learn about Post-COVID Conditions

CDC and partners are doing research on post-COVID conditions in a variety of populations and settings. These partnerships are essential for expanding the base of evidence needed for addressing post-COVID conditions. CDC and its partners are working to:

Characterize and assess post-COVID conditions to provide estimates on the prevalence (number) and incidence (frequency) of people experiencing post-COVID conditions by demographic group, symptom, and new diagnosis. This will allow us to
- Identify risk factors to better understand how to prevent post-COVID conditions.
- Identify groups disproportionately affected by post-COVID conditions.
- Assess the burden (health and financial costs) of post-COVID conditions.
Identify successful interventions to prevent and lessen the effect of post-COVID conditions. This research includes
- Assessing if COVID vaccinations reduce the occurrence of post-COVID conditions.
- Promoting equity in healthcare access and utilization for people with post-COVID conditions.
Disseminate clinical guidance and other education materials for healthcare providers, patients, and the public to improve understanding of post-COVID conditions and reduce stigma.

Science at CDC

Scientific articles and manuscripts about COVID-19 and post-COVID conditions

MMWR COVID-19 Reports CDC Scientific Publications on COVID-19

CDC and partners are collecting and analyzing information about post-COVID conditions and health problems through several public health activities, including

Prospective cohort studies that observe people over time
Sentinel surveillance to collect information from select public health sources on cases of post-COVID conditions
Medical chart abstraction to collect data on the health and medical care of patients with post-COVID conditions
Analyses of electronic healthcare data and large patient databases
State and national health surveys
Evaluation of models of care

Inclusion of data and analyses of post-COVID conditions by race/ethnicity, age, sex, and other factors are a CDC priority.

Related Research

Select examples of research on post-COVID conditions conducted by CDC and partners

FindCOVIDexternal icon

Follows cases in children and adults infected with the virus that causes COVID-19 and their household members to measure initial clinical presentation, viral shedding, transmission, immune response, and on-going symptoms from the time of infection up to 12 months.

Population: Children and adults

Partner: University of California, San Francisco (UCSF)

Immune Response to SARS-CoV-2 among patients in Louisiana

Follows cases in patients recovering from COVID-19 to assess longer term clinical and immunity related outcomes up to one year after the beginning of the illness. Follows a subgroup of cases in COVID-19 patients hospitalized for severe COVID-19 illness for one year following hospital admission.

Population: Adults, with a focus on persons at higher risk for severe COVID-19

Partner: Tulane University School of Medicine, Infectious Diseases

Applied Research to Address the Coronavirus (COVID-19) Emerging Public Health Emergencyexternal icon

Follows cases in participants who report on daily symptoms, testing, care seeking, and vaccination. Conducts monthly testing for antibodies to the virus that causes COVID-19 and analysis of electronic health records to assess ongoing clinical diagnoses, for a minimum of six months.

Population: Adults identified by the University of Maryland and Medstar Health in the mid-Atlantic area, Wake Forest University and Atrium Health System in the North Carolina area, Tulane University, and the University of Mississippi

Partner: COVID-19 Community Research Partnershipexternal icon, Vysnova Partnersexternal icon

COVID – Standardized Evaluation of Long-term Effects (COVID-SELECT)

Collects information from patients at risk of for or who have post-COVID conditions about their health through online questionnaires, with follow up one year later. Information will be used to identify and describe those who have long-term symptoms after having COVID and whose results on routine medical tests and physical examination are normal.

Population: Adults from a demographically diverse population receiving care in a large, integrated health system in northern and central California

Partners: Public Health Foundation Enterprises, Incexternal icon.; California Emerging Infections Programexternal icon; Kaiser Permanente Northern California, Oakland, CA

Characterizing Post-COVID Conditions in the United States

Collects health data to describe the health and medical care of patients at clinics designed for post-COVID care to help classify types of post-COVID health problems and care needed and highlight unmet needs for care in other medical settings.

Population: Adult patients receiving care in post-COVID clinics at participating medical centers through September 30, 2021

Partners: Rainmaker Strategic Solutions, LLC; University of Texas Southwestern Medical Center; Dallas, TX; Creighton University Medical Center, Omaha, NE; Mt. Sinai Health System, New York, NY

Post-COVID Conditions among Patients Seen in Outpatient Settings – American Family Cohort

Analyzes electronic health record data from COVID-19 patients seen at over 800 primary care and family medicine practices to assess frequency of new symptoms and conditions among patients with COVID-19 diagnosis compared with patients with other respiratory diagnoses. Study will assess post-COVID conditions by race/ethnicity, age, sex, geography (urban/rural), and indices of social vulnerability.

Population: Children and adults

Partner: American Board of Family Medicineexternal icon; Stanford University Center for Population Health Sciences

Post-COVID Conditions among Patients Seen in Outpatient and Inpatient Settings – PCORnet

Analyzes electronic health record data from COVID-19 patients seen in ambulatory, emergency department, and hospital settings in 40 U.S. healthcare systems to assess frequency of new symptoms and conditions among patients who tested positive for the virus that causes COVID-19 compared with patients who tested negative.

Population: Children and adults

Partner: PCORnet, the National Patient-Centered Clinical Research Networkexternal icon

Frequency of and Risk Factors for Post-COVID Conditions – Various Healthcare Data Sources

Analyzes several large healthcare data sources to provide estimates of new symptoms and conditions following COVID-19 diagnosis in outpatient and inpatient settings by patient demographic and clinical characteristics.

Population: Children and adults

Data Sources: Cerner HealtheDataLabexternal icon, HealthVerityexternal icon, Premier Healthcare Database Special COVID-19 Release

National Health Interview Survey

Collects information about symptoms of post-COVID conditions through a cross-sectional household survey to estimate the national prevalence of post-COVID conditions.

Population: Adults and children

Data Source: National Center for Health Statistics, CDC

Behavioral Risk Factor Surveillance System

Collects information about symptoms of post-COVID conditions through a survey to produce state/territorial-level estimates of prevalence.

Population: Adults and children

Data Source: National Center for Chronic Disease Prevention and Health Promotion, CDC; participating state and territorial health departments

Multi-state Long Covid Survey

Surveyed adults who tested positive for SARS-CoV-2 for self-reported acute and post-COVID symptoms lasting four weeks or more to estimate prevalence of post-COVID conditions and identify demographic and disease-specific risk factors for developing post-COVID conditions.

Population: Adults who tested positive for the virus that causes COVID-19 in Maine, Wisconsin, New York, and New Jersey

Partners: State health departments

Long COVID and Fatiguing Illness Recovery Program (LC&FIRP)external icon

Evaluates whether educational interventions for primary healthcare providers through a distance-learning platform improves health outcomes of patients with post-COVID conditions and other complex chronic conditions with similar symptoms, such as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and other post-infectious fatiguing illnesses.

Population: Adults who are uninsured, with lower incomes, and who are medically underserved

Partners: Family Health Centers of San Diego (FHCSD), San Diego, Californiaexternal icon; Project ECHO, Albuquerque, NMexternal icon; University of Washington Post-COVID Clinic Rehabilitation and Recovery, Seattle, WAexternal icon; University of Colorado, Denver, CO; ATA Health Strategies, Washington, DC

Interim Clinical Guidance

CDC is sharing information with healthcare providers to support evaluation and care of patients with post-COVID conditions.

Clinical Outreach and Communication Activity (COCA) Calls

The purpose of COCA continuing education opportunities is to increase clinicians’ knowledge and competencies of threats to the public’s health, their effects on human populations, and evaluation and management strategies of these threats. COCA continuing education is free. Learn about receiving continuing education (CE) credit for COCA calls.

Featured Webinars

September 30, 2021: Evaluating and Supporting Patients Presenting with Fatigue Following COVID-19
June 17, 2021: Evaluating and Caring for Patients with Post-COVID Conditions
January 28, 2021: Treating Long COVID: Clinician Experience with Post-Acute COVID-19 Care

More COCA Calls/Webinars

CDC Publications

CDC is publishing the results of studies aimed at better understanding post-COVID conditions and how best to support people experiencing post-COVID conditions and health problems.

Select CDC publications on post-COVID conditions and related topics:

Prospective Cohort Studies

O’Laughlin KN, Thompson M, Hota B, Gottlieb M, Plumb ID, Chang AM, Wisk LE, Hall AJ, Wang RC, Spatz ES, Stephens KA, Huebinger RM, McDonald SA, Venkatesh A, Gentile N, Slovis BH, Hill M, Saydah S, Idris AH, Rodriguez R, Krumholz HM, Elmore JG, Weinstein RA, Nichol G; INSPIRE Investigators. Study protocol for the Innovative Support for Patients with SARS-COV-2 Infections Registry (INSPIRE): A longitudinal study of the medium and long-term sequelae of SARS-CoV-2 infection. PLoS One. 2022 Mar 3;17(3)external icon.
Han JH, Womack KN, Tenforde MW, Files DC, Gibbs KW, Shapiro NI, Prekker ME, Erickson HL, Steingrub JS, Qadir N, Khan A, Hough CL, Johnson NJ, Ely EW, Rice TW, Casey JD, Lindsell CJ, Gong MN, Srinivasan V, Lewis NM, Patel MM, Self WH; Influenza and Other Viruses in the Acutely Ill (IVY) Network. Associations between persistent symptoms after mild COVID-19 and long-term health status, quality of life, and psychological distress. Influenza Other Respir Viruses. 2022 Mar 28external icon.

Analysis of Electronic Healthcare Data

Hernandez-Romieu AC, Leung S, Mbanya A, Jackson BR, Cope JR, Bushman D, Dixon M, Brown J, McLeod T, Saydah S, Datta D, Koplan K, Lobelo F. Health Care Utilization and Clinical Characteristics of Nonhospitalized Adults in an Integrated Health Care System 28-180 Days After COVID-19 Diagnosis – Georgia, May 2020-March 2021. MMWR Morb Mortal Wkly Rep. 2021 Apr 30;70(17):644-650.
Hernandez-Romieu AC, Carton TW, Saydah S, Azziz-Baumgartner E, Boehmer TK, Garret NY, Bailey LC, Cowell LG, Draper C, Mayer KH, Nagavedu K, Puro JE, Rasmussen SA, Trick WE, Wanga V, Chevinsky JR, Jackson BR, Goodman AB, Cope JR, Gundlapalli AV, Block JP. Prevalence of Select New Symptoms and Conditions Among Persons Aged Younger Than 20 Years and 20 Years or Older at 31 to 150 Days After Testing Positive or Negative for SARS-CoV-2. JAMA Netw Open. 2022 Feb 1;5(2)pdf iconexternal icon.
Barrett CE, Koyama AK, Alvarez P, Chow W, Lundeen EA, Perrine CG, Pavkov ME, Rolka DB, Wiltz JL, Bull-Otterson L, Gray S, Boehmer TK, Gundlapalli AV, Siegel DA, Kompaniyets L, Goodman AB, Mahon BE, Tauxe RV, Remley K, Saydah S. Risk for Newly Diagnosed Diabetes >30 Days After SARS-CoV-2 Infection Among Persons Aged <18 Years – United States, March 1, 2020-June 28, 2021. MMWR Morb Mortal Wkly Rep. 2022 Jan 14;71(2):59-65.
Chevinsky JR, Tao G, Lavery AM, Kukielka EA, Click ES, Malec D, Kompaniyets L, Bruce BB, Yusuf H, Goodman AB, Dixon MG, Nakao JH, Datta SD, MacKenzie WR, Kadri SS, Saydah S, Giovanni JE, Gundlapalli AV. Late Conditions Diagnosed 1-4 Months Following an Initial Coronavirus Disease 2019 (COVID-19) Encounter: A Matched-Cohort Study Using Inpatient and Outpatient Administrative Data-United States, 1 March-30 June 2020. Clin Infect Dis. 2021 Jul 15;73(Suppl 1):S5-S16external icon.

Health Surveys

Wanga V, Chevinsky JR, Dimitrov LV, Gerdes ME, Whitfield GP, Bonacci RA, Nji MAM, Hernandez-Romieu AC, Rogers-Brown JS, McLeod T, Rushmore J, Lutfy C, Bushman D, Koumans E, Saydah S, Goodman AB, Coleman King SM, Jackson BR, Cope JR. Long-Term Symptoms Among Adults Tested for SARS-CoV-2 – United States, January 2020-April 2021. MMWR Morb Mortal Wkly Rep. 2021 Sep 10;70(36):1235-1241.

Electronic Medical Chart Abstraction

Rogers-Brown JS, Wanga V, Okoro C, Brozowsky D, Evans A, Hopwood D, Cope JR, Jackson BR, Bushman D, Hernandez-Romieu AC, Bonacci RA, McLeod T, Chevinsky JR, Goodman AB, Dixon MG, Lutfy C, Rushmore J, Koumans E, Morris SB, Thompson W. Outcomes Among Patients Referred to Outpatient Rehabilitation Clinics After COVID-19 diagnosis – United States, January 2020-March 2021. MMWR Morb Mortal Wkly Rep. 2021 Jul 9;70(27):967-971. Erratum in: MMWR Morb Mortal Wkly Rep. 2021 Aug 20;70(33):1126. PMID: 34237048; PMCID: PMC8312758.

Commentary

Saydah SH, Brooks JT, Jackson BR. Surveillance for Post-COVID Conditions Is Necessary: Addressing the Challenges with Multiple Approaches. J Gen Intern Med. 2022 Feb 15:1–3external icon.
Datta SD, Talwar A, Lee JT. A Proposed Framework and Timeline of the Spectrum of Disease Due to SARS-CoV-2 Infection: Illness Beyond Acute Infection and Public Health Implications. JAMA. 2020 Dec 8;324(22):2251-2252external icon.