Cluster-Randomized Trial of Air Filtration and Ventilation to Reduce Covid19 Spread in Homes

NCT05777720 | Completed

• 2 other identifiers: 554795T32AI052073-17
• Study Type: interventional
• Target: 214
• Locations: 1 country
• Sites: 2

Brief Summary

Investigators are evaluating whether an intervention consisting of box-fans with MERV 16 filters ("filtration fans") and recommendations for improving ventilation in the home can reduce secondary spread of Covid19 from an index case to susceptible contacts within the home.

Conditions

Covid19

Keywords

ventilation; air filtration; Covid19; SARS CoV 2; household transmission

Outcome Measures

Primary Outcomes (1)

• Incidence of Covid19

  Investigators will measure the incidence of Covid19 in susceptible contacts on day 7.

  7th day since enrollment in the trial

Secondary Outcomes (2)

• Incidence of new upper respiratory symptoms

  7th day since enrollment in the trial

• Average CO2 levels

  7 days

Study Arms (2)

Control

NO INTERVENTION

No intervention will be administered in this arm. Investigators will give families a CO2 monitor to measure average CO2 levels in the home. Investigators will provide a link to the basic CDC isolation guidelines which would be part of standard of care. Investigators will test family members at day 0-1 for baseline testing; and again on day 7 for assessing secondary transmission among susceptible contacts.

Intervention

EXPERIMENTAL

Families are provided with one filtration fan unit per room in their home (and one for the index case; if the family lives in a studio, they would receive 2 units). Investigators will advise families on ventilation improvements in their home. Investigators will provide an instructional pamphlet that describes how the fans work and the importance of ventilation. Investigators will follow-up on day 3-4 to check in and run through a checklist to ensure the fans are working and ventilation improvements are being attempted. Investigators will give families a CO2 monitor to measure average CO2 levels in the home. Investigators will test family members at day 0-1 for baseline testing; and again on day 7 for assessing secondary transmission among susceptible contacts.

Device: Filtration Fan; Behavioral: Safe-home pamphlet; Behavioral: Mid-week phone call

Interventions

Filtration Fan DEVICE

Investigators are using box fans with attached MERV16 filters, a design that has been tested and published in the scientific literature.

Intervention

Safe-home pamphlet BEHAVIORAL

The pamphlet has information on how the filtration fans work through visual images; and images of ventilation improvements in the home through opening windows.

Intervention

Mid-week phone call BEHAVIORAL

On day 3-4 of the study, the study coordinator assigned to the house will call and check in regarding the filtration fan usage and remind families about the importance of filtration and ventilation.

Intervention

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Household members live in a shared space (apartment, home) with others (as opposed to renting single rooms in a shared space, for example)
• At least 3 other people live in the household aside from index case

You may not qualify if:

• If index case test positive day was over 2 days prior
• If half or more household members are thought to be infected already
• If household has fewer than 3 contacts interested in participating in the study
• If fewer than 3 contacts are expected to be present in the house for a majority of the following 7 days

Sponsors & Collaborators

• Stanford University: lead
• National Institute of Allergy and Infectious Diseases (NIAID): collaborator

Study Sites (2)

San Mateo Medical Center

San Mateo, California, 94403, United States

Location

Stanford University Medical Center

Stanford, California, 94305, United States

Location

MeSH Terms

Conditions

COVID-19; Respiratory Aspiration

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases; Respiration Disorders; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Yvonne Maldonado, MD

  Stanford University

  STUDY DIRECTOR

• Abraar Karan, MD

  Stanford University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Post-Doctoral Fellow

Study Record Dates

• First Submitted: March 18, 2023
• First Posted: March 21, 2023
• Study Start: January 30, 2023
• Primary Completion: December 30, 2025
• Study Completion: December 30, 2025
• Last Updated: February 19, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)