Coronaviruses are a large group of viruses that cause diseases in animals and humans. There are seven known human coronaviruses, all of which get their name from the “corona” or halo surrounding the virus particle when it is viewed under electron microscopy. They often circulate among animals and can sometimes evolve and infect people. In humans, the viruses can cause mild respiratory infections, similar to those seen when a person has a common cold, but can lead to serious illnesses, like pneumonia and respiratory failure in an infected person.

A “novel” organism is one that has not been previously identified and to which humans have not been exposed. The novel coronavirus (SARS-CoV-2) that caused the disease Coronavirus Disease 2019 (COVID-19) emerged in a seafood and poultry market in Wuhan, China, in December 2019. The illness was declared a Public Health Emergency of International Concern on January 30, 2020. On March 11, 2020, COVID-19 was declared a pandemic by the World Health Organization (WHO). On March 13, 2020, a national emergency was declared in the United States as a result of the COVID-19 outbreak.

Human-to-human transmission of COVID-19 occurs through close contact. Individuals infected with COVID-19 have had a wide variety of symptoms, ranging from mild to severe. While some infected individuals may not have any symptoms, others require ventilator support, and many have died. Symptoms usually appear two to 14 days after exposure to the virus and may include:

  • fever
  • cough
  • shortness of breath or difficulty breathing
  • chills
  • fatigue
  • muscle pain or body aches 
  • headache
  • sore throat
  • loss of taste or smell
  • congestion or runny nose
  • nausea or vomiting
  • diarrhea.

Although the virus can affect anyone, those who are at greater risk of severe illness from COVID-19 include:

  • Older adults
  • People with chronic medical conditions like sickle cell disease, cardiac disease, lung disease (such as COPD), type 2 diabetes, obesity (BMI > 30), and kidney disease
  • Patients who are immunocompromised from a transplant or cancer
  • People with asthma, high blood pressure, neurologic conditions such as dementia, strokes, or who are pregnant may be at risk for more severe illness.

Children with COVID-19 most often have mild, cold-like symptoms including fever, runny nose, cough, nausea, and diarrhea.

Currently, there are three types of COVID-19 tests. The types of tests include:

  • Molecular tests used to detect the genetic material of SARS-CoV-2, the virus that causes COVID-19;
  • Antigen tests that can detect fragments of the virus from nasal swabs; and
  • Antibody (or serology) tests that detect the body’s immune response to COVID-19 by looking for antibodies in the blood to determine prior exposure. When the body is fighting or has fought an infection, antibodies can be found in the blood from a past infection or exposure.

Tests can return varying degrees of false negatives. If a negative test is documented on a patient record, but the provider documents that the patient has COVID-19, then COVID-19 should be coded.

There is an urgent need to capture the reporting of this condition in the nation’s claims and surveillance data for the Centers for Disease Control. On January 31, the World Health Organization convened an emergency meeting to discuss creation of an ICD-10-code that would be used to track the disease. An emergency code was established – U07.1 – to represent the virus that was later officially named as COVID-19.

The ICD-10-CM Official Coding and Reporting Guidelines (April 1, 2020 through September 30, 2020) Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99), g. Coronavirus Infections instructs coders in assigning correct ICD-10 codes for tracking this virus. These instructions are summarized below.

  • Code only confirmed cases of COVID-19 using code U07.1
    • As documented by the provider;
    • When there is documentation of a positive COVID-19 test result; or
    • There is a presumptive positive COVID-19 test result. A presumptive positive test result means a patient has tested positive for the virus at a local or state level, but it has not yet been confirmed by the Centers for Disease Control and Prevention (CDC).
    • This is an exception to the hospital inpatient guideline Section II, H that states, “In this context, “confirmation” does not require documentation of the type of test performed; the provider’s documentation that the patient has COVID-19 is sufficient.
    • If the provider documented “suspected,” “possible,” “probable,” or “inconclusive” COVID-19, do not assign U07.1. Instead:
      • Assign a code(s) explaining the reason for the encounter (such as “fever”) or Z20.828, “Contact with and (suspected) exposure to other viral communicable diseases.”
  • Sequencing of Codes
    • When COVID-19 meets the definition of principal diagnosis, code U07.1, COVID-19 should be sequenced first, followed by the appropriate codes for associated manifestations. 
      • EXCEPTION: Obstetric patients as indicated in Section.I.C.15.s. for COVID-19 in pregnancy, childbirth and the puerperium. 
      • Acute Respiratory Illness due to COVID-19:
        • Pneumonia due to COVID-19 assign:
          – U07.1, COVID-19 (Principal)
          – J12.89, Other viral pneumonia
        • Acute bronchitis due to COVID-19
          – U07.1, COVID-19 (Principal)
          – J40, Bronchitis, not specified as acute or chronic
        • Lower respiratory infection due to COVID-19
          – U07.1, COVID-19 (Principal)
          – J22, Unspecified acute lower respiratory infection
        • Acute Respiratory Distress Syndrome due to COVID-19
          – U07.1, COVID-19 (Principal)
          – J80, Acute Respiratory Distress Syndrome (ARDS)
  • Exposure to COVID-19
    • When there is a concern about a possible exposure to COVID-19 but it rules out after evaluation, assign code Z03.818, “Encounter for observation for suspected exposure to other biological agents ruled out”
    • Patient who has had an actual; exposure to someone who is confirmed or suspected (not ruled out) to have COVID-19, and the exposed individual eithers tests negative or the test results are unknown, assign Z20.828, “Contact with and (suspected) exposure to other viral communicable diseases”
  • Screening for COVID-19
    • For asymptomatic individuals who are being screened for COVID-19 and have no known exposure to the virus, and test results are unknown or negative, assign code Z11.59, “Encounter for screening for other viral diseases”
  • Signs and symptoms without definitive diagnosis of COVID-19
    • Patients presenting with signs/symptoms associated with COVID-19 (such as fever, etc.) but a definitive diagnosis has not been established, assign the appropriate code(s) for each of the presenting signs and symptoms, such as:
      • R05, Cough
      • R06.02, Shortness of breath
      • R50.9, Fever, unspecified
    • If the patient with signs and symptoms associated with COVID-19 also has an actual or suspected contact with, or exposure to, someone who has COVID-19, assign Z20.828, “Contact with and (suspected) exposure to other viral communicable diseases”
  • Asymptomatic individuals who test positive for COVID-19
    • Assign code U07.1, COVID-19
  • For a COVID-19 infection that progresses to sepsis
    • When COVID-19 and sepsis are documented in the record, refer to the sepsis coding guidelines that are printed in the ICD-10-CM Official Guidelines for Coding and Reporting, FY2020, pp. 24-27. The sequencing of COVID-19 and sepsis will depend on the circumstances of admission. Here are a few examples of sequencing and coding of sepsis and COVID-19:
      • COVID-19 and sepsis both documented and present on admission
        • A41.89, Other specified sepsis (Principal)
        • U07.1, COVID-19
      • COVID-19 present on admission and sepsis develops after admission
        • U07.1, COVID-19 (Principal)
      • A41.89, if the documentation is not clear whether the sepsis was present on admission, the provider should be queried for clarification
  • Patient who is admitted with sepsis due to COVID-19 who also has Acquired Immune Deficiency Syndrome
    • Patients with human immunodeficiency virus (HIV) are more susceptible to being infected by COVD-19 due to immune compromise. HIV does not cause COVID-19. The sequencing would be based on the circumstances of the admission.

The specific diagnosis code assignment would be determined by whether or not the provider documents the sepsis as an HIV-related illness. Sepsis is identified as an HIV-related illness; however, coders cannot assume a linkage between the two conditions. Coding Clinic for ICD-10-CM/PCS, first quarter, 2019, states: “The specific DRG assignment would be determined by whether or not the provider documents the sepsis as an HIV-related illness. Sepsis is identified as an HIV-related illness but coders cannot assume a linkage between the two conditions unless documented by the provider.”

Per Coding Clinic for ICD-10-CM/PCS, first quarter, 2019, states: “Provider documentation must specifically indicate AIDS or that the patient has an HIV-related illness prior to assigning code B20, Human immunodeficiency virus [HIV] disease. It would not be appropriate to automatically link a diagnosis as an HIV-related condition based solely on the CDC’s AIDS-Defining Illnesses list and/or conditions included in MDC 25. If the documentation is unclear or ambiguous regarding the patient’s HIV status, the provider should be queried for clarification.”

    • Diagnosis codes B20, A41.89, and U07.1 (COVID-19) would be assigned if the documentation specifies a linkage of the two conditions OR,
    • Assigned as A41.89, U07.1, Z21, in the absence of linking documentation by the provider and no documentation to support prior HIV-related conditions to allow the reporting of B20.
    • If sepsis developed solely after inpatient admission, U07.1 could also meet the criteria for principal diagnosis if that was the reason for admission. Additional codes would be assigned for sepsis and the HIV status.
  • COVID-19 Infection in Pregnancy, Childbirth and the Puerperium (Codes from Chapter 15 always take sequencing priority).
    • During pregnancy, childbirth or the puerperium, a patient admitted (or presenting for a health care encounter) because of COVID-19
    • Principal diagnosis: O98.5-, Other viral diseases complicating pregnancy, childbirth and the puerperium
    • Secondary diagnosis: U07.1, COVID-19, and the appropriate codes for associated manifestation(s).

Coders must be cognizant of the most current instructions that have been given regarding coding for COVID-19. Sequencing is also critical. As noted by an FAQ from the American Hospital Association/American Health Information Management Association, “When COVID-19 meets the definition of principal or first-listed diagnosis, code U07.1, COVID-19, should be sequenced first, and followed by the appropriate codes for associated manifestations, except in the case of obstetric patients. However, if COVID-19 does not meet the definition of principal or first-listed diagnosis (e.g., when it develops after admission), then code U07.1 should be used as a secondary diagnosis.”