A99 - Unspecified viral hemorrhagic fever

Version 2023
ICD-10:A99
Short Description:Unspecified viral hemorrhagic fever
Long Description:Unspecified viral hemorrhagic fever
Status: Valid for Submission
Version:ICD-10-CM 2023
Code Classification:
  • Certain infectious and parasitic diseases (A00–B99)
    • Arthropod-borne viral fevers and viral hemorrhagic fevers (A90-A99)
      • Unspecified viral hemorrhagic fever (A99)

A99 is a billable ICD-10 code used to specify a medical diagnosis of unspecified viral hemorrhagic fever. The code is valid during the fiscal year 2023 from October 01, 2022 through September 30, 2023 for the submission of HIPAA-covered transactions.

Unspecified diagnosis codes like A99 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Clinical Information

Index to Diseases and Injuries References

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for this diagnosis code are found in the injuries and diseases index:

Convert to ICD-9 Code

Source ICD-10 CodeTarget ICD-9 Code
A99065.9 - Arthropod hem fever NOS
Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education


Hemorrhagic Fevers

Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by four families of viruses. These include the Ebola and Marburg, Lassa fever, and yellow fever viruses. VHFs have common features: they affect many organs, they damage the blood vessels, and they affect the body's ability to regulate itself. Some VHFs cause mild disease, but some, like Ebola or Marburg, cause severe disease and death.

VHFs are found around the world. Specific diseases are usually limited to areas where the animals that carry them live. For example, Lassa fever is limited to rural areas of West Africa where rats and mice carry the virus.

The risk for travelers is low, but you should avoid visiting areas where there are disease outbreaks. Because there are no effective treatments for some of these viral infections, there is concern about their use in bioterrorism.

Centers for Disease Control and Prevention


[Learn More in MedlinePlus]

Code History