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  6. 2025 ICD-10-CM Code B99

2025 ICD-10-CM Diagnosis Code B99

Other and unspecified infectious diseases

ICD-10-CM Code:
B99
ICD-10 Code for:
Other and unspecified infectious diseases
Is Billable?
Not Valid for Submission
Code Navigator:

B99 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of other and unspecified infectious diseases. The code is not specific and is NOT valid for the year 2025 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Unspecified diagnosis codes like B99 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.

Specific Coding Applicable to Other and unspecified infectious diseases

Non-specific codes like B99 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for other and unspecified infectious diseases:

  • Use B99.8 for Other infectious disease - BILLABLE CODE

  • Use B99.9 for Unspecified infectious disease - BILLABLE CODE

Code Classification

  • Certain infectious and parasitic diseases
    A00–B99
    • Other infectious diseases
      B99
      • Other and unspecified infectious diseases
        B99

Index to Diseases and Injuries References

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

Patient Education


Infectious Diseases

What are infectious diseases?

Germs, or microbes, are found everywhere - in the air, soil, and water. There are also germs on your skin and in your body. Many of them are harmless, and some can even be helpful. But some of them can make you sick. Infectious diseases are diseases that are caused by germs.

What are the different types of germs that cause infectious diseases?

There are four main types of germs:

  • Bacteria are one-celled germs that multiply quickly. They may give off toxins, which are harmful chemicals that can make you sick. Strep throat and urinary tract infections are common bacterial infections.
  • Viruses are tiny capsules that contain genetic material. They invade your cells so that they can multiply. This can kill, damage, or change the cells and make you sick. Viral infections include HIV and the common cold.
  • Fungi are primitive plant-like organisms such as mushrooms, mold, mildew, and yeasts. Athlete's foot and yeast infections are common fungal infections.
  • Parasites are animals or plants that survive by living on or in other living things. Malaria and head lice are infections that are caused by parasites.

How can you get infectious diseases?

There are many different ways that you can get an infectious disease, depending on the type of germ. They can include:

  • Through direct contact with a person who is sick. This includes kissing, touching, sneezing, coughing, and sexual contact. Pregnant people can also pass some germs along to their babies.
  • Through indirect contact, when you touch something that has germs on it. For example, you could get germs if someone who is sick touched a door handle, and then you touch it.
  • Through insect or animal bites.
  • Through contaminated food, water, soil, or plants.

What are the symptoms of infectious diseases?

Infectious diseases can cause many different symptoms. Some are so mild that you may not even notice any symptoms, while others can be life-threatening.

What are the treatments for infectious diseases?

There are treatments for some infectious diseases, such as antibiotic, antiviral, antifungal and anti-parasitic medicines. But for other infections, such as some caused by viruses, you can only treat your symptoms while you wait for your immune system to fight off the germ.

Can infectious diseases be prevented?

You can take steps to help prevent many infectious diseases:

  • Get vaccinated.
  • Wash your hands often.
  • Pay attention to food safety.
  • Avoid contact with wild animals.
  • Use a latex condom every time you have sex. If your or your partner is allergic to latex, you can use polyurethane condoms.
  • Don't share items such as toothbrushes, combs, and straws.

[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.