| Z20 | Contact with and (suspected) exposure to communicable diseases | NON-BILLABLE CODE |
| Z20.0 | Contact with and (suspected) exposure to intestinal infectious diseases | NON-BILLABLE CODE |
| Z20.01 | Contact with and (suspected) exposure to intestinal infectious diseases due to Escherichia coli (E. coli) | BILLABLE CODE |
| Z20.09 | Contact with and (suspected) exposure to other intestinal infectious diseases | BILLABLE CODE |
| Z20.1 | Contact with and (suspected) exposure to tuberculosis | BILLABLE CODE |
| Z20.2 | Contact with and (suspected) exposure to infections with a predominantly sexual mode of transmission | BILLABLE CODE |
| Z20.3 | Contact with and (suspected) exposure to rabies | BILLABLE CODE |
| Z20.4 | Contact with and (suspected) exposure to rubella | BILLABLE CODE |
| Z20.5 | Contact with and (suspected) exposure to viral hepatitis | BILLABLE CODE |
| Z20.6 | Contact with and (suspected) exposure to human immunodeficiency virus [HIV] | BILLABLE CODE |
| Z20.7 | Contact with and (suspected) exposure to pediculosis, acariasis and other infestations | BILLABLE CODE |
| Z20.8 | Contact with and (suspected) exposure to other communicable diseases | NON-BILLABLE CODE |
| Z20.81 | Contact with and (suspected) exposure to other bacterial communicable diseases | NON-BILLABLE CODE |
| Z20.810 | Contact with and (suspected) exposure to anthrax | BILLABLE CODE |
| Z20.811 | Contact with and (suspected) exposure to meningococcus | BILLABLE CODE |
| Z20.818 | Contact with and (suspected) exposure to other bacterial communicable diseases | BILLABLE CODE |
| Z20.82 | Contact with and (suspected) exposure to other viral communicable diseases | NON-BILLABLE CODE |
| Z20.820 | Contact with and (suspected) exposure to varicella | BILLABLE CODE |
| Z20.821 | Contact with and (suspected) exposure to Zika virus | BILLABLE CODE |
| Z20.822 | Contact with and (suspected) exposure to COVID-19 | BILLABLE CODE |
| Z20.828 | Contact with and (suspected) exposure to other viral communicable diseases | BILLABLE CODE |
| Z20.9 | Contact with and (suspected) exposure to unspecified communicable disease | BILLABLE CODE |
