The CHARM network will be established through three primary institutions-Beth Israel Deaconess Medical Center (BIDMC), the University of California San Diego (UCSD), and the University of Washington (UW)-along with their subcontracting institutions. At UCSD and partner sites, the CHARM network will be implemented via the PREVENT project. All PREVENT participants will be consented in to Component A0 (Community Testing) and a subset of A0 participants will be invited to participate and will be consented into the other components: Component A (Ongoing Testing); Component A Sub-study (Immunology); Component B (Household Transmission).

Component A0 participants (Community testing) will be members of the community who are interested in accessing testing for respiratory infections and will be asked to provide limited information that will then be used for screening for study Components A and/or B.

Participants in Component A (Ongoing Testing ) will undergo weekly symptom screening. If they report symptoms, they will be asked to provide a nasal swab and complete illness questionnaires on the day they report symptoms (Day 0) and again on Days 7 and 14. Participants in Component A Sub-study (Immunology) will provide blood and saliva/nasal fluid samples twice a year, as well as before and after infection and/or immunization against priority pathogens.

Participants in Component B (Household Transmission) will complete daily symptom questionnaires and nasal swabs for 14 days following enrollment, regardless of symptoms. Those who are symptomatic at enrollment will also complete retrospective daily diaries from symptom onset to the enrollment date. Additionally, they provide blood and/or saliva/nasal fluid samples at enrollment and again 28 days later.

For all Components, UCSD will provide PCR test results for SARS-CoV-2, Influenza A/B, and RSV for nasal swab samples.

Community Testing Component:

Inclusion:

- All community members are able to participate in the community testing component.

Exclusion:

- There is no exclusion criteria and participants will not be excluded based on pregnancy status or age.

For Component A:

Inclusion:

• All ages
• AND Lives in service area of a recruitment center (i.e., within range of courier pick up)
• AND Plans to remain living in a recruitment area for the next 2 years.

Exclusion:

• Inability to communicate in a language in which consent forms, materials, etc. are available
• OR Incarcerated
• OR Living in a congregate setting (e.g., assisted living, nursing home, university dormitories with shared bathroom and communal eating facilities)
• OR Unable/unwilling to participate in planned data and specimen collections
• OR Unable to comply with study procedures, as determined by study investigators
• OR Participation in clinical trials of investigational agents for respiratory viral infections during the three months prior to enrollment and for the duration of the study.

For Component B:

Inclusion:

Index case:

• Detection of priority respiratory pathogen via laboratory or point-of-care test on the day of eligibility screening or in the previous 5 days, AND
• Lives in service area of a recruitment center (i.e., within range of courier pick up), AND
• Lives in a household with ≥1 other person and plans to remain in the household for at least the duration of specimen collection (i.e., 14 days), AND
• Has not been hospitalized since the date of symptom onset.

Household contacts:

• Routinely sleep in the same household as index case and slept in household ≥1 night in the 7 days before index case symptom onset, AND
• Plan to remain in the household for at least the duration of specimen collection (i.e., 14 days).

Household:

• There is ≥1 non-ill household member (i.e., asymptomatic and has not tested positive for the virus of the index case) on the day of eligibility screening or in the previous 5 days,
• AND all symptomatic persons in the household had a symptom or diagnosis onset date on the day of eligibility screening or in the previous 5 days.

Exclusion:

Index case:

• Lives in a congregate setting (e.g., assisted living, nursing home, university dormitories with shared bathroom and communal eating facilities)
• Meet any A1 exclusion criteria

Household contacts:

• Has been hospitalized any time since date of primary case symptom onset
• Meets any A1 exclusion criteria

Household:

• The enrollment visit occurs >6 days after the first symptom onset of primary case
• The primary case in the household is not enrolled
• The primary case has been hospitalized any time after the date of symptom onset

Investigators will include a large portion of San Diego County, which resides in HHS Region 9 and is the Southwestern-most county in the continental U.S, abutting the U.S./Mexico border.

Limited datasets with HIPAA data restricted to date of birth, date of study activities, and residence at the level of ZIP code/census tract will be shared with the study sponsor (CDC) and other investigators in the CHARM network, through a joint MTA/DUA and shared study Protocol and Dana Management Plan.