COVID-19 Hospital Encounters by Week From Selected Hospitals

COVID-19 Hospital Data

The National Hospital Care Survey (NHCS), conducted by the National Center for Health Statistics (NCHS), collects data on patient care in hospital-based settings to describe patterns of health care delivery and utilization in the United States. Settings currently include inpatient facilities and emergency departments (ED). The survey collects electronic data, Uniform Bill (UB–04) administrative claims or electronic health records, for all encounters in a calendar year from a nationally representative sample of 601 hospitals. Information collected includes diagnoses, procedures, demographics, discharge status, and patient identifiers (e.g., name and date of birth). Eligible hospitals are in the 50 states and the District of Columbia and include noninstitutional and nonfederal hospitals with six or more staffed inpatient beds.  Hospitals are currently being received into the survey.

The NHCS results provided on COVID-19 hospital use are from UB–04 administrative claims data from March 18, 2020 through September 26, 2023 from 23 hospitals that submitted inpatient data and 23 hospitals that submitted ED data. The data used in these figures are considered preliminary, and the results may change with subsequent releases. There will be updates every two months to the data file. The data are not nationally representative. Even though the data are not nationally representative, they can provide insight on the impact of COVID-19 on various types of hospitals throughout the country.

Results on this page show the percentage of new confirmed COVID-19, suspected COVID-19, and non-COVID-19 encounters among all ED or inpatient encounters over time. Data are presented for each setting (inpatient and ED) and for each week, by age and sex. These categories are defined by an any listed International Classification of Diseases, 10th Revision, Clinical Modification (ICD–10–CM) diagnosis code as follows:

  • Confirmed—A confirmed COVID-19 hospital encounter is defined as an any listed ICD–10–CM diagnosis code of B97.29 and/or U07.1. Prior to April 1, 2020, CDC guidance stated to code a confirmed COVID-19 hospital encounter as B97.29. On April 1, 2020, the guidance changed to code confirmed COVID-19 hospital encounters as U07.1. The figure shows the percentage of hospital encounters coded with a B97.29 and/or U07.1 code.
  • Suspected—A suspected COVID-19 hospital encounter in 2020 is defined by an ICD–10–CM code of contact with and (suspected) exposure to other viral communicable diseases (Z20.828) and in 2021 it is defined by an ICD-10-CM code of contact with and (suspected) exposure to COVID-19 (Z20.822). Additionally, suspected encounters do not contain any confirmed codes. In early versions (March 18, 2020 – December 29, 2020) of this figure, suspected COVID-19 was defined by the ICD-10-CM code for COVID-19, virus not identified (U07.2) or coronavirus infection, unspecified (B34.2). Also, the earlier version included potential COVID-19 hospital encounters as having an ICD–10–CM code for pneumonia (J12.89), acute bronchitis (J20.8, J40), lower respiratory infection (J22, J98.8), or Acute Respiratory Distress Syndrome (J80). The potential portion of the definition was removed for this update due to revised CDC guidance for coding suspected COVID-19. See the related links below for coding guidelines.
  • Non-COVID-19—A non-COVID-19 encounter includes all other ICD–10–CM codes not mentioned above and excludes confirmed and suspected COVID-19 codes.

  • 3,726,805 ED encounters and 1,404,796 inpatient discharges.
  • For weeks where there are less than 30 encounters in the denominator, data are suppressed. In the figure, weeks with suppressed data do not have a corresponding data point on the indicator line.

Technical Notes

  • Data are not nationally representative.
  • Less than 1% of all encounters were excluded due to missing sex, age, or a diagnosis.
  • Hospitalizations related to childbirth are included in the denominator for females.
  • 9.1% of inpatient discharges were for newborn (ICD–10–CM: Z38) encounters and are excluded.
  • Data represent encounters, not patients.
  • Weeks with less than 30 encounters in the denominator are suppressed.


Data Source

The data presented are from the 2020, 2021, 2022 and 2023 NHCS. The data in these figures are considered preliminary and are not nationally representative. All estimates shown meet the  NCHS Data Presentation Standards for Proportions.

The goal of NHCS is to produce national estimates on hospital care and utilization. The survey is designed to produce objective and timely data to assess the health and well-being of the population and the performance and functioning of the health care system. For more details about NHCS, visit the National Hospital Care Survey website.


Related Links