Hello, Our office is billing influenza A and B with Strep Tests on one claim for hundreds of kiddos. We use CPT 87804 QW, 87804 59,QW and 87880 QW with the ICD code for Fever. Our claims were being denied for not having a valid principal diagnosis. We switched to billing with J02.9 Acute Pharyngitis and J10.1 but these are denied for the same reason. Can anyone help me with this? I read online that we can't bill both strep and flu together? Is that correct? Any help is appreciated!!