participants who meet any of the following criteria will be excluded from the study. 1. participants with acute illnesses or hospitalizations within 30 days of the study start, and/or planned procedures during study participation, and/or newly diagnosed chronic illnesses that are not deemed stable by the participant's primary care physician), based on investigator assessment of medical history during screening. 2. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening (see section 6.6.2). 3. participants with any prior history of sars-cov-2 infection. 4. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone within the last 7 days. 5. participants who underwent a previous tracheostomy. 6. participants who are receiving any form of oxygen therapy. 7. females who are breastfeeding, pregnant, or attempting to become pregnant. 8. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. 1. participants with acute illnesses or hospitalizations within 30 days of the study start, and/or planned procedures during study participation, and/or newly diagnosed chronic illnesses that are not deemed stable by the participant's primary care physician), based on investigator assessment of medical history during screening. 2. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening (see section 6.6.2). 3. participants with any prior history of sars-cov-2 infection. 4. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone within the last 7 days. 5. participants who underwent a previous tracheostomy. 6. participants who are receiving any form of oxygen therapy. 7. females who are breastfeeding, pregnant, or attempting to become pregnant. 8. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. participants with acute illnesses or hospitalizations within 30 days of the study start, and/or planned procedures during study participation, and/or newly diagnosed chronic illnesses that are not deemed stable by the participant's primary care physician), based on investigator assessment of medical history during screening. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening (see section 6.6.2). participants with any prior history of sars-cov-2 infection. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone within the last 7 days. participants who underwent a previous tracheostomy. participants who are receiving any form of oxygen therapy. females who are breastfeeding, pregnant, or attempting to become pregnant. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. participants with acute illnesses or hospitalizations within 30 days of the study start, and/or planned procedures during study participation, and/or newly diagnosed chronic illnesses that are not deemed stable by the participant's primary care physician), based on investigator assessment of medical history during screening. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening (see section 6.6.2). participants with any prior history of sars-cov-2 infection. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone within the last 7 days. participants who underwent a previous tracheostomy. participants who are receiving any form of oxygen therapy. females who are breastfeeding, pregnant, or attempting to become pregnant. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening. participants with any prior history of sars-cov-2 infection. participants who have received any dose of sars-cov-2 vaccine. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone. participants who underwent a previous tracheostomy. participants who are receiving concomitant treatment of respiratory support (involving any form of oxygen therapy). females who are breastfeeding, pregnant, or attempting to become pregnant. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening. participants with any prior history of sars-cov-2 infection. participants who have received any dose of sars-cov-2 vaccine. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone. participants who underwent a previous tracheostomy. participants who are receiving concomitant treatment of respiratory support (involving any form of oxygen therapy). females who are breastfeeding, pregnant, or attempting to become pregnant. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. 1. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening. 2. participants with any prior history of sars-cov-2 infection. 3. participants who have received any dose of sars-cov-2 vaccine. 4. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone. 5. participants who underwent a previous tracheostomy. 6. participants who are receiving concomitant treatment of respiratory support (involving any form of oxygen therapy). 7. females who are breastfeeding, pregnant, or attempting to become pregnant. 8. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.

participants who meet any of the following criteria will be excluded from the study. 1. participants with any respiratory infection, flu-like symptoms, or unexplained fever or chills during the week prior to screening. 2. participants with any prior history of sars-cov-2 infection. 3. participants who have received any dose of sars-cov-2 vaccine. 4. participants who use intranasally dosed drugs, prescriptions or over-the-counter medications such as fluticasone. 5. participants who underwent a previous tracheostomy. 6. participants who are receiving concomitant treatment of respiratory support (involving any form of oxygen therapy). 7. females who are breastfeeding, pregnant, or attempting to become pregnant. 8. participants who have any other condition that, in the opinion of the investigator, would interfere with a participant's ability to adhere to the protocol (eg, participants whom are mentally or neurologically disabled and whom are considered not fit to their participation in the study), interfere with assessment of the investigational product, or compromise the safety of the participant or the quality of the data.