These frequently asked questions accompany the webinar ICD-10-CA Coding Direction for COVID-19 and address some of the most common questions about classifying COVID-19–related cases.

About COVID-19

What is COVID-19?

COVID-19 (coronavirus disease 2019) is a disease caused by a new strain of coronavirus not previously identified in humans.

  • A confirmed COVID-19 case is one that has been diagnosed by a positive COVID-19 lab result. A confirmed COVID-19 case is classified to U07.1 COVID-19, virus identified.
  • A suspected COVID-19 case is one that has been diagnosed clinically or epidemiologically but lab results are inconclusive or not available, or testing is not performed. A suspected COVID-19 case is classified to U07.2 COVID-19, virus not identified.

COVID-19 documentation

Is U07.2 or Z03.8 assigned when the physician documents “COVID-19 negative”?

U07.2 COVID-19, virus not identified is not assigned when the physician documents “COVID-19 negative.” U07.2 is assigned when COVID-19 has been diagnosed clinically or epidemiologically but lab results are inconclusive or not available, or testing is not performed.

Z03.8 Observation for other suspected diseases and conditions may be assigned in an emergency department encounter when 

  • The patient presents with a sign or symptom (e.g., dry cough); and 
  • The physician documents a diagnosis such as “rule out COVID-19” or “suspected COVID-19”; and 
  • At the time of coding, the coder has access to the COVID-19 lab result, which is negative. 

It is in this circumstance that the 3 criteria, per the Admission for Observation coding standard, have been met to justify assigning Z03.8:

  • The suspected condition (COVID-19) was ruled out by a negative COVID-19 lab result; and
  • There is no documentation to support that further investigation is required; and
  • Another underlying condition is not documented.

In an acute inpatient episode of care, when the physician documents “COVID-19 negative,” neither U07.2 nor Z03.8 is assigned. Code assignment is based on the physician’s documented final diagnosis.

Which code is assigned as the main problem for a patient who presents to the emergency department with a fever when the physician documents the diagnosis as “rule out COVID-19” and the COVID-19 lab results are negative?

Assign Z03.8 Observation for other suspected diseases and conditions as the main problem. The patient presented with a symptom (fever) and the physician documented the diagnosis in terms of suspected COVID-19. COVID-19 was ruled out with the negative COVID-19 lab result, and another underlying condition as the cause of the sign (fever) was not documented. The 3 criteria, per the Admission for Observation coding standard, have been met:

  • The suspected condition (COVID-19) was ruled out; and
  • There is no documentation to support that further investigation is required; and
  • Another underlying condition is not identified.

Which code is assigned when multiple COVID-19 lab results are negative for COVID-19 but the physician documents the final diagnosis as “possible COVID-19”?

The case should be discussed with the physician to determine whether 

  • They documented the final diagnosis before the COVID-19 lab results were back and they have to adjust the final diagnosis accordingly; or 

  • They are aware of the negative COVID-19 lab results, feel the lab results are inconclusive and still suspect COVID-19. 

U07.2 COVID-19, virus not identified is assigned when COVID-19 is diagnosed clinically or epidemiologically but lab results are inconclusive.

Is U07.1 COVID-19, virus identified assigned when the patient is transferred from one hospital to another for convalescence following treatment for COVID-19?

Yes, per the Admission for Convalescence coding standard, assign a code from category Z54 Convalescence as the most responsible diagnosis and assign an additional code, mandatory, as a diagnosis type (3) to indicate the condition for which convalescence is required. In this case, U07.1 (3) COVID-19, virus identified is assigned.

Which code is assigned when there is documentation that a COVID-19 nasopharyngeal swab was taken but there is no documentation of COVID-19 status (neither suspected nor confirmed), nor is there any documentation of signs and symptoms suggestive of COVID-19?

Flag the chart and update the code assignment when the lab results are available.

Which code is assigned when the patient presents to the emergency department with a symptom suggestive of COVID-19 (e.g., sore throat) and a COVID-19 nasopharyngeal swab is taken?

See the table “Main problem (MP) and other problem (OP) code assignment for emergency department COVID-19–related cases” in the bulletin ICD-10-CA Coding Direction for Suspected COVID-19 Cases. There are examples that demonstrate code assignment for various scenarios: when the patient presents with a sign or symptom and a COVID-19 nasopharyngeal swab is taken and the COVID-19 lab results come back positive, come back negative, or are inconclusive or not available.

Is U07.1 or U07.2 always the main problem on a NACRS abstract?

While we would expect to see U07.1 COVID-19, virus identified or U07.2 COVID-19, virus not identified as the main problem (MP) on a National Ambulatory Care Reporting System (NACRS) abstract, there may be circumstances when it is an other problem (OP). When in doubt, submit a coding question via eQuery with a copy of the pertinent de-identified clinical documentation.

COVID-19 lab results

Do the lab results specify COVID-19 or coronavirus?

Coronaviruses (CoVs) are a large family of viruses that cause illness ranging from the common cold to more severe diseases; they include the Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome–associated coronavirus (SARS-CoV). COVID-19 is caused by a new strain of coronavirus. 

When COVID-19 testing is performed, the lab results will specifically identify whether the swab was negative or positive for COVID-19. The COVID-19 lab results may be used to inform code assignment. That is, a confirmed case of COVID-19, classified to U07.1 COVID-19, virus identified, is determined by a positive COVID-19 lab result and a suspected case of COVID-19 is ruled out by a negative COVID-19 lab result. 

The direction for coders to use COVID-19 lab results is an exception to the direction provided in the coding standard Using Diagnostic Test Results in Coding. Use the COVID-19 lab results to confirm or rule out COVID-19. When the lab results identify any other causative organism, such as coronavirus HKU or OC43, they may not be used to inform code assignment. In these circumstances, a code is assigned only when the physician documents the diagnosis as due to the causative organism identified in the lab result.

Do we assign U07.1 COVID-19, virus identified when the COVID-19 lab results are positive for COVID-19 but there is nothing documented by the physician?

Yes, you may use the positive COVID-19 lab result and assign U07.1 COVID-19, virus identified. Application of diagnosis/problem type will depend on the documented details for the episode of care.

Does a continuous, uninterrupted episode of care include transfers from another facility?

Yes, a continuous, uninterrupted episode of care starts at the point the patient first accesses the health care system and runs through the continuum of care until the patient is discharged. For COVID-19, accessing a COVID-19 assessment centre is included in the continuum. As soon as the patient is discharged, the continuous, uninterrupted episode of care ends.

COVID-19 diagnosis typing

Can service transfer diagnosis typing — i.e., diagnosis type (W), (X), (Y) — be applied to U07.1 COVID-19, virus identified and U07.2 COVID-19, virus not identified?

Yes, if your facility tracks service transfers and U07.1 COVID-19, virus identified or U07.2 COVID-19, virus not identified qualifies as the service transfer diagnosis, it is appropriate to apply a service transfer diagnosis type.

Can diagnosis type (2) be applied to U07.1 COVID-19, virus identified and U07.2 COVID-19, virus not identified?

Yes, per the Diagnosis Typing Definitions for DAD coding standard, diagnosis type (2) is applied when a condition that arises post-admission has been assigned an ICD-10-CA code and has been determined to meet at least 1 of the 3 criteria for significance. Apply diagnosis type (2) when lab-confirmed COVID-19 or suspected COVID-19 is acquired following admission.

When another condition such as a stroke qualifies as the most responsible diagnosis, is diagnosis type (1) applied to U07.1 COVID-19, virus identified in a patient who tests positive for COVID-19?

Per the Diagnosis Typing Definitions for DAD coding standard, diagnosis type (M) is the one diagnosis that can be described as being most responsible for the patient’s length of stay in hospital. If there is more than one such condition, the one held most responsible for the greatest portion of the length of stay or greatest use of resources is diagnosis type (M). When a stroke qualifies as the most responsible diagnosis, diagnosis type (1) may be applied to U07.1 COVID-19, virus identified.

COVID-19 screening

When a patient is admitted to an acute care inpatient bed with a diagnosis such as colon cancer or acute myocardial infarction or with injuries due to a motor vehicle crash and hospital protocol is to test (screen) for COVID-19, is Z11.5 Special screening examination for other viral diseases assigned?

Z11.5 is assigned when the sole purpose of the episode of care is to “screen” for COVID-19. We would expect to see Z11.5 on an emergency department abstract when the encounter is specific to screening for COVID-19 and not on an acute care inpatient abstract. The intent is not to identify all patients who were tested for COVID-19 and for whom the lab result is negative. Z11.5 Special screening examination for other viral diseases is not assigned when the COVID-19 lab result is negative on an acute care inpatient abstract. Code assignment is based on the physician’s documented final diagnosis.

When a patient is admitted to an acute care inpatient bed with a diagnosis such as colon cancer or acute myocardial infarction or with injuries due to a motor vehicle crash and is tested for COVID-19 because he has a cough and the COVID-19 lab result comes back negative, is diagnosis type (1) applied to R05 Cough?

Diagnosis type (1) is not applied to R05 Cough when the patient is tested for COVID-19 and the lab result comes back negative. See the criteria for significance in the Diagnosis Typing Definitions for DAD coding standard. A lab test is not one of the criteria for significance.

COVID-19 follow-up

Is U07.1 COVID-19, virus identified or Z09.9 Follow-up examination after unspecified treatment for other conditions assigned when a patient who previously tested positive for COVID-19 presents for re-testing that comes back negative for COVID-19? What if the COVID-19 lab result comes back positive again?

Per the Admission for Follow-Up Examination coding standard, when the purpose of the examination is to assess the status of a previously treated condition and the outcome indicates no need for further treatment, assign the appropriate code from category Z09 Follow-up examination after treatment for conditions other than malignant neoplasms. When the examination reveals that the original condition still exists or has recurred, assign a code for the condition. When a patient who previously tested positive for COVID-19 presents for re-testing and the COVID-19 lab result comes back negative, assign Z09.9 Follow-up examination after unspecified treatment for other conditions. If the COVID-19 lab result comes back positive, assign U07.1 COVID-19, virus identified

COVID-19 and palliative care

When a patient with cancer is known to be palliative and also tests positive for COVID-19, are the codes for the cancer also assigned?

Yes, per the Palliative Care coding standard, assign Z51.5 Palliative care and additional code(s), mandatory, to describe the palliative condition(s). 

COVID-19 and convalescence

When a patient is admitted for convalescence and is admitted to an isolation unit as a precaution during the COVID-19 pandemic, is a significant diagnosis type applied to Z29.0 Isolation?

In this circumstance, Z29.0 Isolation is assigned, optionally, to flag that the patient required isolation, based on the facility’s data needs. When a patient is admitted for convalescence, significance is ascribed to the convalescence and a code is assigned, mandatory, as a diagnosis type (3) to indicate the condition for which convalescence is required.

COVID-19 resources

What classification resources are available for COVID-19?

A number of resources are available on CIHI’s COVID-19 resources web page. Classification resources include the following:

Clients can find answers to COVID-19–related questions submitted to eQuery by searching eQuery on key words “U07.1,” “U07.2” or “COVID-19.” If you require assistance with coding a specific case, submit your question and pertinent de-identified clinical documentation via eQuery.

Send your questions about the Canadian Emergency Department Diagnosis Shortlist (CED-DxS) to nacrspicklists@cihi.ca.