Anosmic patients will be recruited from Dr. Albers Smell Clinic at MGH and through past participation in research with known anosmia and permission to recontact. All consent and testing will occur on a phone/tablet app in the participant's home.

Asymptomatic participants recruited in a hospital setting (eg. healthcare workers and household members of symptomatic patients who are potentially COVID positive). No symptoms of COVID infection at the time of enrollment. Potential or definite exposure to SARS-CoV-2 virus without symptoms of upper respiratory infection (smell loss, taste loss, fever, myalgia, cough, nasal congestion, runny nose, shortness of breath). All consent and testing will occur on a phone/tablet app in the participant's home.

Individuals who tested positive for SARS-CoV2 by an objective PCR or antigen test will be recruited to evaluate smell function weekly over 3 months. All consent and testing will occur on a phone/tablet app in the participant's home.

Known history of CSD (chemosensory dysfunction) associated with a COVID-19 infection characterized in Dr.Lora Bankova's clinical study (MGB) .

The AROMHA Longitudinal Smell Test is a self-administered, at-home smell test intended for use as a screening test by asymptomatic individuals to help prevent exposure to and spread of SARS-CoV-2, the virus that causes COVID-19, through a serial testing approach. The device consists of six versions of a smell card, each containing three unique odors.

The Aromha Smell Test is a battery of 18 odors across 6 smell cards. The subject smells each of the 3 scents per card to determine smell intensity, identification, and discrimination. Increased number of correct responses indicates better sense of smell. We will evaluate previously diagnosed anosmic patients.

The Aromha Smell Test is a battery of 18 odors across 6 smell cards. The subject smells each of the 3 scents per card to determine smell intensity, identification, and discrimination. Increased number of correct responses indicates better sense of smell. The subject's scores on the longitudinal olfactory tests will be compared to the self-reported COVID test results (SARS-CoV-2 negative or positive) of asymptomatic and symptomatic individuals.

The BSIT is a battery of 12 odors with a score range from 0-12. Higher scores indicate a better sense of smell. We will evaluate previously diagnosed anosmic patients and healthy asymptomatic controls.

To compare results of the Aromha Longitudinal smell test with test results of upper respiratory illnesses.