Z23 — Encounter for immunization
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- Influenza vaccine claims must contain HCPCS G0008 and diagnosis ICD-10 Z23.
- Pneumococcal vaccine claims must contain HCPCS G0009 and diagnosis ICD-10 Z23.
- When pneumococcal and influenza vaccines are given the same visit, claims should contain HCPCS G0008 AND G0009 and ICD-10 Z23.
- Hepatitis B vaccine claims must contain HCPCS G0010 and diagnosis ICD-10 Z23 and documentation of patient risk status (e.g., ESRD, hemophilia, household contact, sexual/drug-use risk, healthcare worker, institutional resident/staff).
Key Coverage Criteria
- COVID-19 vaccines are covered under Medicare Part B (see CMS guidance for vaccine pricing and coding).
- Seasonal influenza vaccine is covered once per flu season (use codes 90635, 90637, 90638, 90653-90657, 90660-90662, 90672-90674, 90682, 90685-90689, 90694, 90695, 90756, Q2034-Q2039).
- Pneumococcal vaccine is covered as an initial dose for Medicare beneficiaries who have never received a pneumococcal vaccine under Medicare Part B (use codes 90670, 90671, 90677, 90732).
- A different, second pneumococcal vaccine is covered when administered at least 1 year after the first pneumococcal vaccine.
- Pneumococcal and seasonal influenza vaccines administered during the same visit are both covered (bill seasonal influenza and pneumococcal vaccine codes).
- Hepatitis B vaccine is covered only for persons at intermediate-to-high risk (use codes 90739-90740, 90743-90744, 90746-90747, 90759).
13 Active Policies
AMBETTER-CP.MP.97 — Testing for Select Genitourinary Conditions
AETNA-CPB-0035 — Influenza Vaccine
AETNA-CPB-0037 — Pneumococcal Vaccines
AETNA-CPB-0115 — Varicella and Herpes Zoster Vaccines
AETNA-CPB-0318 — Palivizumab (Synagis)
Related Codes
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