The purpose of this research study is to find out how well two different 2023-2024 updated COVID-19 vaccines protect people from COVID-19 (the disease caused by the SARS-CoV-2 virus), and to determine if getting a 2023-2024 updated vaccine provides better protection from COVID-19 than not getting a vaccine.

If the participant chooses to get a 2023-2024 updated COVID-19 vaccine as part of this study, they will have a 50/50 chance of receiving either the Novavax or Pfizer mRNA vaccine.

If the participant decides not to get a 2023-2024 updated COVID-19 vaccine, the participant can still participate in other study activities.

STUDY ACTIVITIES:

• An online enrollment survey
• An in-person enrollment visit
• Weekly online surveys for 20 weeks
• Weekly COVID-19 tests for 20 weeks
• Additional online surveys if you have COVID-19 symptoms or tested positive for COVID-19.
• Additional COVID-19 tests if you have COVID-19 symptoms or tested positive.
• Online survey questions in the middle and at the end of the study

For the BEEHIVE Study, UT seeks to enroll 1,500 participants living in the greater Salt Lake City area during the upcoming 2023-2024 COVID-19 season. Participants who intend to get vaccinated with the 2023-2024 updated COVID-19 vaccine (n=1200) will be randomized into the NVX vaccine group or the Pfizer mRNA vaccine group. Participants will be randomized 1:1 to receive 1 dose of the NVX vaccine versus 1 dose of the Pfizer mRNA vaccine from October to December 2023 (dates may vary slightly based on vaccine availability). Participants who decide not to receive a 2023-2024 updated COVID-19 vaccine during this period will be placed in a non-randomized comparison group (n=300).

Participants in all three study arms will complete an online enrollment survey and will self-schedule an in-person enrollment visit. During the visit, all participants will receive a supply of at-home rapid antigen tests for SARS-CoV-2 infection. Those who choose to be in the vaccinated group will also receive either the Novavax vaccine or the Pfizer mRNA vaccine at random. On the first, second, and seventh day after receiving the vaccine, participants will complete an online post-vaccination survey. Beginning after the enrollment visit for a period of 24 weeks, all participants will complete a weekly rapid at-home test and a weekly online survey that surveils for COVID-like illness (CLI)-associated SARS-CoV-2 virus infection, defined as symptoms in the past 7 days including: fever; chills; malaise; fatigue; headache; cough; shortness of breath; sore throat; runny nose or nasal congestion; nausea or vomiting; diarrhea; muscle or body aches; or change in smell or taste. Participants will upload a photo of each weekly test result to the study portal. Those who report new CLI symptoms and those who test positive on their at-home test will complete additional online surveys concerning their illness, as well as another at-home test on the first and third day after the original test. Additionally, all participants will complete a mid- and end-of study survey about their work, health, and opinions about COVID-19, and any COVID-19 and influenza vaccines received. Finally, participants who tested positive for COVID-19 during the study or who had COVID-19 symptoms but did not test positive will complete an online survey about the duration of symptoms and impact on their health. By Summer 2024, study staff will inform participants when the weekly surveys will end and when to stop testing. At the end of the study, participants in the vaccinated group will be notified of which study vaccine they received.

Inclusion Criteria:

• Age ≥18 years
• Previously received ≥ 2-doses of US FDA-authorized mRNA vaccines
• Comfortable reading and responding to text messages and emails sent in English or having an interpreter assist them
• Plan to remain in the greater Salt Lake City area for the next 12 months
• Daily access to the internet (via cell phone, laptop, desktop, or tablet) and a phone with text messaging capabilities
• Willingness to complete weekly symptom and illness surveillance surveys sent via text and email
• Willingness to complete an online survey at enrollment, mid-study, and end-of-study surveys
• Willingness to be contacted periodically by study staff via text, email, and/or telephone as part of study activities
• Willingness to self-collect rapid antigen tests (RAT; approved by FDA EUA for COVID-19 detection) weekly and when prompted for study purposes, and to send results via the study portal
• Willingness to self-collect additional rapid antigen test (approved by FDA EUA for COVID-19 detection) if experiencing a qualifying symptomatic illness or upon RAT-confirmation of an asymptomatic infection
• Willingness to attend in-person visit to receive supply of rapid antigen tests and training on their use (all participants) and to receive a COVID-19 booster (if in randomized group)

Exclusion Criteria:

• Lives with another person who is already enrolled in this study as reported by the subject on the Eligibility Survey (Appendix C. Eligibility Survey)
• Previous hypersensitivity reaction to the study vaccines as reported by the subject on the Eligibility Survey (Appendix C. Eligibility Survey)
• Recent infection [Real time Reverse Transcription Polymerase Chain Reaction assay (RT-PCR) and/or RAT confirmed infection ≤ 90 days of trial vaccine administration
• Receipt of a COVID-19 vaccine within ≤ 90 days of trial vaccine administration
• Participation in other vaccine trials
• Medical history of immunosuppression
• Receipt of J&J vaccine prior to study enrollment
• Receipt of any investigational prevention therapies for SARS-CoV-2 infections, such as prophylactic antiviral medications or other immune system modifying interventions within ≤ 90 days of trial vaccine administration
• Unwillingness to provide electronic consent
• Unwillingness to self-report occupation, work responsibilities, and prior COVID-19 illness.](streamdown:incomplete-link)

Participants will elect whether they are in the vaccinated group or decline to be in the vaccinated group. So, all participants will be aware of their group assignment. However, those participants in the vaccinated group as well as study investigators will be blinded to study arm assignments within the vaccinated group. A limited number of study staff handling and administering the vaccines will be aware of vaccine assignment and will be trained not to divulge vaccine assignment information to the investigator and study team. Study staff administering vaccine will not be involved with study surveillance to avoid involvement with measurement of study outcomes. The study will provide electronic documentation confirming that participants received one of the study vaccines (without indicating which vaccine) with date of vaccine administration. The electronic documentation of vaccine administration will be password protected to maintain blinding.