NIH Clinical Center Search the Studies: Study Number, Study Title

Protocol Details

Transmissibility and Viral Load of SARS-CoV-2 Through Oral Secretions

This study is NOT currently recruiting participants.

Summary | Eligibility | Citations | Contacts




Sponsoring Institute

National Institute of Dental And Craniofacial Research (NIDCR)

Recruitment Detail

Type: Completed Study; data analyses ongoing
Gender: Male & Female
Min Age: 18
Max Age: N/A

Referral Letter Required


Population Exclusion(s)

Non-English Speaking;


Natural History

Recruitment Keyword(s)




Investigational Drug(s)


Investigational Device(s)




Supporting Site

National Institute of Dental and Craniofacial Research


COVID-19 is a worldwide pandemic and currently there is no effective therapy or vaccine. SARS-CoV-2, the virus that causes the COVID-19 respiratory infection, appears to be very contagious however all the modes of transmission are unclear. Transmission may occur in up to 25 percent of cases when there are no symptoms (asymptomatic). Before there are any symptoms, droplet spray during speaking may increase transmission from person to person; most of the spray is saliva. Researchers at the NIH would like to test saliva for the virus before symptoms are reported. Additionally, they would like to examine the importance of using masks to prevent transmission. They hope to better understand how COVID-19 is spread among people and how it can be prevented. For this study they would like to collect samples from the nose (nasopharyngeal swab), mouth (spit sample), eye (conjunctival fluid) and blood to test for the virus and if it is contagious.


To determine if the SARS-CoV-2 virus is present in saliva in asymptomatic individuals who are COVID-19 positive. To determine if using masks can prevent transmission.


People ages 18 and older without symptoms or with mild symptoms (e.g., low grade fever,

mild malaise, minor sore throat, runny nose, or sneezing) who have been in close contact (e.g. live in the same house) with someone who has tested positive for COVID-19 or people who have tested positive for COVID-19 and have mild (e.g., low grade fever, mild malaise, minor sore throat, runny nose, or sneezing) or no symptoms.

Design and Procedures:

For screening, interested participants will contact a study team member. The interested participant will be asked to provide documentation of COVID-19 positive status, their symptoms, or their contact to a COVID-19 positive person.

Participants will be asked to come to the NIH drive-up COVID-19 testing site or NIH Clinical Center (Bethesda, MD) for 2 or more visits in 15 days for the following procedures: nasal swab for COVID-19 and viral load, verbal symptom assessment, saliva collection, and speaking exercise to capture oral fluid. During this time, participants will also be asked to participate in phone calls with the study staff and to complete questionnaires electronically. Participants will have weekly telephone calls to discuss their symptoms and 2-5 drive-up visits to the NIH within 28 days. If visits are scheduled at the Clinical Center, participants will have the option to participate in providing blood sample(s), a conjunctival swab and 1-2 salivary gland biopsies.

If a participant has tested positive, they may be asked to return to the NIH after they have recovered from COVID-19 for additional sampling.

The following procedures are part of this research:

- Speaking exercise - participants will be asked to read a short script with and without wearing a mask. The droplets they produce while they speak will be collected.

- Saliva collection - participants will spit into a cup and have saliva collected from different areas of the mouth. They should not eat 90 minutes before this but drinking water or juice is acceptable. They may have their tongue painted with a sour liquid to increase their saliva.

- Nasal swab- participants will have a swab rubbed inside their nose.

- Nasopharyngeal swab - participants that are close contacts of COVID-19 positive individual(s) and need a COVID-19 test, will have a swab inserted through the nose to rub the back of their throat.

- Questionnaires - participants will complete questionnaires about their symptoms electronically at home.

The following procedures are optional for participants to agree to participate in and will be performed in the Clinical Center:

- Blood sample(s) - participants will have blood collection via venipuncture.

- Conjunctival swab - participants will have the inner lower eyelid wiped with swab.

- Minor salivary gland biopsy - participants will have tiny glands in mouth removed. Procedure will be done in the hospital.

Participants will be paid up to a total of $300 for the study, based on the number of visits to NIH and the types of procedures performed. Payment will be: $50 on Day 1, Day 15 and at the recovery visit. Participants who agree to the optional conjunctival swab and/or biopsy will be paid $50 for each conjunctival swab (up to 1) and/or $50 for each salivary biopsy (up to 2).

If at any time the participants start to have moderate or severe respiratory symptoms, their participation in the study will end and they should seek care with their local provider.

--Back to Top--



In order to be eligible to participate in this study, an individual must meet all the following criteria:

1. Willing and able to sign and date the informed consent form

2. Willing to comply with all study procedures and available for study visits and calls

3. Male or female, aged >= 18 years of age

4. Persons who test COVID-19 positive in past 48 hours (verbal confirmation followed by documented test results, sent electronically) and are asymptomatic or have mild symptoms (e.g., fever, mild malaise, sore throat or sneezing) individuals who have re-tested and are negative may be enrolled to understand progression and resolution of disease; persons hospitalized at the NIH Clinical Center meeting Inclusion Criteria 1-3 may be enrolled on this study

5. Persons considered high risk for COVID-19 due to personal contact within the past 7 days with a COVID-19 positive individual (e.g., co-habitating family member of COVID-19 positive) and has no symptoms or mild symptoms of COVID-19 - verbal confirmation followed by documented test results of positive individual, sent electronically


An individual who meets any of the following criteria will be excluded from participation in this study:

1. COVID-19 positive subjects with active moderate or severe symptoms of cough or shortness of breath (upper and lower respiratory symptoms) or currently requiring hospitalization at a hospital other than NIH Clinical Center (recovering COVID-19 positive patients can be enrolled).

--Back to Top--


To KK, Tsang OT, Leung WS, Tam AR, Wu TC, Lung DC, Yip CC, Cai JP, Chan JM, Chik TS, Lau DP, Choi CY, Chen LL, Chan WM, Chan KH, Ip JD, Ng AC, Poon RW, Luo CT, Cheng VC, Chan JF, Hung IF, Chen Z, Chen H, Yuen KY. Temporal profiles of viral load in posterior oropharyngeal saliva samples and serum antibody responses during infection by SARS-CoV-2: an observational cohort study. Lancet Infect Dis. 2020 Mar 23. pii: S1473-3099(20)30196-1. doi: 10.1016/S1473-3099(20)30196-1. [Epub ahead of print]

Rubin EJ, Baden LR, Morrissey S. Audio Interview: Lessons from Covid-19 Hotspots. N Engl J Med. 2020 Apr 2;382(14):e35. doi: 10.1056/NEJMe2007783.

Fauci AS, Lane HC, Redfield RR. Covid-19 - Navigating the Uncharted. N Engl J Med. 2020 Mar 26;382(13):1268-1269. doi: 10.1056/NEJMe2002387. Epub 2020 Feb 28.

--Back to Top--


Principal Investigator

Referral Contact

For more information:

Blake M. Warner, D.D.S.
National Institute of Dental And Craniofacial Research (NIDCR)
(301) 500-8063

Eileen M. Pelayo
National Institute of Dental And Craniofacial Research (NIDCR)
National Institutes of Health
Building 10
Room 1N110
10 Center Drive
Bethesda, Maryland 20892
(301) 594-3097

Office of Patient Recruitment
National Institutes of Health Clinical Center (CC)
Building 61, 10 Cloister Court
Bethesda, Maryland 20892
Toll Free: 1-800-411-1222
Local Phone: 301-451-4383
TTY: TTY Users Dial 7-1-1

Clinical Trials Number:


--Back to Top--