Remember how 90654 (Influenza virus vaccine, split virus, preservative-free, for intradermal use) went into effect Jan. 1, 2011? Now you can see it in your CPT manual. Also, you'll see modifier 33 (Preventive services) printed in your CPT manual. It, too, went into effect Jan. 1, 2011. This modifier allows you to tell your payer that you performed a preventive service and that the patient's deductible and coinsurance do not apply under the new Patient Protection and Affordable Care Act (PPACA) rules. Part B pay: