Retroactive for dates of service on or after July 24, 2009, H1N1 testing using real-time RT-PCR assay is now a Medi-Cal benefit. Testing is allowed for H1N1 using two units of CPT code 87798 (infectious agent detected by nucleic acid [DNA], amplified probe technique) when billed with ICD-9-CM diagnosis code 488.1 and modifier 59 (distinct procedural service).
Providers must submit original claims and/or resubmit a Claims Inquiry Form (CIF) for previously paid claims which were cut back to a quantity of one. All resubmitted and original claims must be billed with modifier 59 and ICD-9-CM diagnosis code 488.1.
Source: General Medicine | August 2010 | Bulletin 434