Table 1.

Key elements of a successful false-positive mitigation plan.

Elements	Corrective actions
Verify the source of false-positive(s)	Confirm SARS-CoV-2 genetic marker(s) via gel-electrophoresis and/or sequencing. Use appropriate controls (e.g., field negative, method negative, and no-template) to identify sample collection, processing where contaminant(s) is/are introduced.
	RT-PCR method step(s) where contaminant(s) is/are introduced.
Expunge contamination from the test environment	Use aseptic technique and properly disinfect/sterilize all sample collection equipment, devices, bottles, and other laboratory consumables.
	Discard all unsealed consumables and reagents throughout entire method.
	Thoroughly clean all work area surfaces and equipment.
RT-PCR method updates (varies by source)	Strict enforcement of unidirectional laboratory workflow and dedicated equipment practices.
	Implement additional contamination monitoring for responsible step.
	Use different reagent lots.
	Use customized reagents that minimize carryover amplification contamination such as UNG.
	Additional analyst training.
Demonstrate absence of contamination	Use appropriate controls (e.g., field negative, method negative, and no template) to verify that contamination has been eliminated.