- diagnosis of covid-19 within 2 months prior to enrollment, or active respiratory illness symptoms at time of enrollment - known medical contraindication to chlorhexidine gluconate or povidone-iodine treatment ingredients (such as a known allergy) - participant has a known medical and/or surgical reason prohibiting nasal swab sampling. - participant is female who is pregnant, or believes she may be pregnant, at time of enrollment. - participant is actively taking/using any treatments or interventions as part of any other covid-19 related investigational trials.

- diagnosis of covid-19 within 2 months prior to enrollment, or active respiratory illness symptoms at time of enrollment - known medical contraindication to chlorhexidine gluconate or povidone-iodine treatment ingredients (such as a known allergy) - participant has a known medical and/or surgical reason prohibiting nasal swab sampling. - participant is female who is pregnant, or believes she may be pregnant, at time of enrollment. - participant is actively taking/using any treatments or interventions as part of any other covid-19 related investigational trials.