A Study of SARS CoV-2 Infection and Potential Transmission in Individuals Immunized With Moderna COVID-19 Vaccine

The purpose of this study is to assess SARS CoV-2 infection, viral shedding, and subsequent potential transmission in individuals immunized with the Moderna COVID-19 vaccine.

This study will evaluate the efficacy of the Moderna COVID-19 vaccine against SARS-CoV-2 infection, as well as its effect on peak nasal viral load as a measure of infection and a proxy of infectiousness, in adults aged 18-29.

In the Main study, up to 12,000 participants will be randomized 1:1 to Immediate Vaccination Group 1 (at Months 0 and 1) or Standard of Care Group 2, with vaccination given at Months 4 and 5 if not received off-study previously. Up to an additional 6,000 participants will be enrolled into the Vaccine Declined Group 3 and will also be offered vaccine at Months 4 and 5.

Additional study visits for Group 1 will occur at Months 2 and 4; for Groups 2 and 3, at Months 0 and 2. Study visits may include medical history, vaccine injections, blood collection, nasal swab, SARS-CoV-2 screening, COVID-19 symptom check, and questionnaires.

In addition to the main study participants, the study will also evaluate infectiousness following close contacts with main study participants. Study procedures for close contacts include questionnaires and blood samples; for those who become SARS-CoV-2 infected, study procedures will also include nasal swabs.

Eligibility Criteria:
Inclusion criteria for Main cohort, Vaccine Declined Group General and Demographic Criteria

* Age of 18 through 29 years.
* Ability and willingness to provide informed consent.
* Prefers not to receive COVID-19 vaccine.
* Willingness to be followed for the planned duration of the study.
* Assessment of understanding: volunteer demonstrates understanding of this study; completes a questionnaire with demonstration of understanding of all questionnaire items answered incorrectly.
* Access to device and internet for completion of study procedures.

Exclusion criteria for Main cohort, Vaccine Declined Group

* Prior administration of a coronavirus (SARS-CoV-2, SARS-CoV, MERS-CoV) vaccine or current/planned simultaneous participation in another interventional study to prevent or treat COVID-19 (participation in studies of other investigational research agents allowed).
* Any medical, psychiatric, occupational, or other condition that, in the judgment of the investigator, would interfere with, or serve as a contraindication to, protocol adherence, or a volunteer's ability to give informed consent.

Inclusion criteria for Prospective Close Contact (PCC) cohort

* Age of 18 years or older, at the time of signing the informed consent.
* Willing and able to provide informed consent.
* Expected to be in frequent close physical proximity with Main Cohort participant during the study.
* Willing to share results of SARS-CoV-2 testing.
* Access to device and internet for completion of study procedures

Inclusion criteria for Case-ascertained Close Contact (CACC) cohort

* Age of 18 years or older, at the time of signing the informed consent.
* Willing and able to provide informed consent.
* Access to device and internet for completion of study procedures.
* Willing to share results of SARS-CoV-2 testing.
* Had close contact with Main Cohort participant with known PCR-confirmed SARS-CoV-2 infection (eg, index case). Close contacts will have had exposure to the index participant, generally within 72 hours of an index diagnosis, and may include individuals that meet any of the following guidelines:

Prolonged close physical proximity with Main Cohort participant within a residence/vehicle/enclosed space without maintaining social distance,

Medical staff, first responders, or other care persons who cared for the index case without appropriate personal protective equipment.

Further information on the definition of close contact can be found in the CoVPN 3006 Study Specific Procedures (SSP).