A Human Influenza Transmission Study Using Naturally Infected Community Donors

NCT07814495 | Not Yet Recruiting

• 1 other identifier: 2026P001601
• Study Type: interventional
• Target: 150
• Locations: 1 country
• Sites: 2

Brief Summary

The purpose of this study is to determine whether influenza A or B can be transmitted from adults with naturally acquired community influenza infection to healthy adult recipients under controlled inpatient exposure conditions, and to identify donor, recipient, viral, immunologic, behavioral, and environmental factors associated with transmission. This study differs from a traditional influenza CHIM because no challenge stock will be administered. Instead, naturally infected community donors will serve as the source of exposure. This approach is intended to better reflect naturally circulating influenza viruses and naturally infected donors while preserving the safety advantages of inpatient monitoring, defined exposure windows, controlled environmental measurements, and standardized sampling.

Conditions

Influenza

Outcome Measures

Primary Outcomes (4)

• Proportion of Participants Developing Influenza Infection

  Secondary attack rate of laboratory-confirmed influenza infection among exposed recipients, defined as the proportion of healthy adult recipients who develop laboratory-confirmed influenza A or B infection after controlled exposure to one or more naturally infected adult community donors within the quarantine period.

  During the quarantine period (up to Day 14)

• Number of Recipients Experiencing A Serious Adverse Event

  Safety of controlled exposure to naturally infected influenza donors in healthy adult recipients is assessed by the number and proportion of exposed recipients with serious adverse events.

  Up to Day 91

• Number of Recipients with Severe Influenza Disease

  Safety of controlled exposure to naturally infected influenza donors in healthy adult recipients is assessed by the number and proportion of exposed recipients with severe influenza disease. Severe influenza disease is defined as laboratory-confirmed influenza A or B infection plus persistent Grade 3 severity in respiratory rate, tachycardia, blood pressure, oxygen saturation, or temperature not attributed to another cause and sustained for two days; radiologically confirmed pneumonia; organ involvement such as encephalitis or myocarditis; or investigator determination that the clinical syndrome represents severe influenza disease.

  Up to Day 91

• Number of Recipients Experiencing an Adverse Event

  Safety of controlled exposure to naturally infected influenza donors in healthy adult recipients is assessed by the number and proportion of exposed recipients with adverse events.

  Up to Day 31

Secondary Outcomes (6)

• Frequency of Viral Shedding in Recipients

  During the quarantine period (up to Day 14)

• Timing of Viral Shedding in Recipients

  During the quarantine period (up to Day 14)

• Duration of Viral Shedding in Recipients

  During the quarantine period (up to Day 14)

• Magnitude of Viral Shedding in Recipients

  During the quarantine period (up to Day 14)

• Number of Symptomatic Recipient Participants

  During the quarantine period (up to Day 14)

Study Arms (2)

Influenza Donors

OTHER

Adults with naturally acquired community influenza A or B infection are enrolled as donors.These donors are not experimentally infected by the study. Instead, donors are identified rapidly from the community, tested by rapid antigen and/or polymerase chain reaction (PCR), and brought to the controlled exposure unit for same-day donor visits.

Other: Influenza Donor Visit

Influenza Recipients

EXPERIMENTAL

Healthy adult recipients are admitted to the Emory University Hospital challenge unit and intentionally exposed to one or more naturally infected donors under controlled inpatient conditions over multiple exposure days.

Other: Influenza Recipient Inpatient Exposures Sessions

Interventions

Influenza Donor Visit OTHER

Donor participants will have screening/testing with a same-day donor visit. The donor visit involves a donor exposure session and/or research sampling prior to discharge from donor visit.If eligible, repeat donor visits are possible. Study staff will monitor exposure sessions and will stop a session for participant safety or donor clinical deterioration.

Influenza Donors

Influenza Recipient Inpatient Exposures Sessions OTHER

Recipient are admitted to the Emory University Hospital challenge unit in cohorts of 2-10 recipients. Each cohort may be exposed to one or more naturally infected donors over up to 7 donor-exposure days. Exposure sessions may last up to 4 continuous hours and no more than 8 total exposure hours per day. During exposure sessions, donors and recipients may participate in structured social activities such as conversation, reading aloud, singing, games, light group activities, and shared-object activities. Environmental conditions may be collected to help interpret transmission outcomes. Recipients testing negative may be discharged 4 days after last exposure, while those testing positive may be discharged 7 days after the last exposure day before conversion, with discharge delayed if not clinically stable. Outpatient follow-up occurs for up to 91 days with an optional visit at Day 365 for research sampling.

Influenza Recipients

Eligibility Criteria

• Age: 18 Years - 49 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Provide written informed consent before initiation of any study procedures.
• Are able to understand and comply with all planned study procedures, including inpatient quarantine, donor-exposure sessions, infection-control procedures, symptom reporting, specimen collection, and follow-up.
• Healthy adults aged ≥18 and ≤49 years at the time of first donor exposure.
• Participants who can become pregnant must be practicing abstinence or using an acceptable method of contraception for at least 30 days before first donor exposure and through Day 91. A participant is considered not of childbearing potential if post-menopausal or surgically sterilized.
• Participants who can become pregnant must have a negative serum or urine pregnancy test at screening and a negative urine pregnancy test within 24 hours before first donor exposure.
• Are in good general health, as determined by the PI or designee, and do not have medical conditions that increase risk for influenza complications, including but not limited to:
• Chronic pulmonary disease, including asthma or emphysema.
• Chronic cardiovascular disease, including cardiomyopathy, congestive heart failure, prior cardiac surgery, ischemic heart disease, or known anatomic cardiac defects.
• Chronic medical conditions requiring close medical follow-up or hospitalization during the past 5 years, including diabetes mellitus, renal dysfunction, or hemoglobinopathies.
• Immunosuppression, ongoing malignancy, or history of malignancy, excluding non-melanotic skin cancer in remission without treatment for more than 5 years.
• Neurologic or neurodevelopmental conditions, including cerebral palsy, epilepsy, stroke, or seizures.
• History of post-infectious or post-vaccine neurologic sequelae.
• Autoimmune, inflammatory, vasculitic, or rheumatic disease, including but not limited to systemic lupus erythematosus, polymyalgia rheumatica, rheumatoid arthritis, or scleroderma.
• Demonstrate knowledge and comprehension of the study by scoring ≥70% on a quiz of study procedures, risks, and policies.
• Agree not to use cigarettes, e-cigarettes, marijuana, or other tobacco products during the quarantine period.

You may not qualify if:

• Have household contact with, or daily contact with:
• Children under 5 years of age.
• Children or teenagers receiving long-term aspirin therapy.
• Persons who are pregnant or trying to become pregnant.
• Persons older than 65 years of age.
• Persons of any age with significant chronic medical conditions, including chronic pulmonary disease, chronic cardiovascular disease, chronic metabolic disease, renal dysfunction, hemoglobinopathy, immunosuppression, cancer, or neurologic/neurodevelopmental conditions.
• Are healthcare workers with patient contact during the two weeks after final donor exposure or discharge from quarantine.
• Plan to live in a confined environment, such as a ship, camp, dormitory, shelter, or other congregate setting, during the two weeks after final donor exposure or discharge from quarantine.
• Are breastfeeding or plan to breastfeed through Day 91.
• Have a body mass index less than or equal to 18.5 or greater than or equal to 35.
• Smoke more than four cigarettes, e-cigarettes, marijuana, or other tobacco products on a weekly basis within 60 days before first donor exposure.
• Have moderate or severe illness within 7 days before admission or first donor exposure, including but not limited to oral temperature ≥100°F, diarrhea, or vomiting.
• Had laboratory-confirmed influenza in the current season or influenza-like illness in the current season.
• Have a pulse rate less than 55 beats per minute or greater than 100 beats per minute. If the pulse rate is \<55 beats per minute and the PI or designee determines this is not clinically significant, such as in an athletic participant, and the heart rate increases to \>55 beats per minute with moderate exercise, the participant will not be excluded.
• Have systolic blood pressure less than 90 mmHg or greater than 140 mmHg on two separate measurements.

Sponsors & Collaborators

• Emory University: lead
• National Philanthropic Trust (NPT): collaborator

Study Sites (2)

Emory University Hospital (EUH)

Atlanta, Georgia, 30322, United States

Location

Hope Clinic

Atlanta, Georgia, 30322, United States

Location

MeSH Terms

Conditions

Influenza, Human

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Study Officials

• Nadine Rouphael, MD, MSc

  Emory University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Nadine Rouphael, MD, MSc

CONTACT

404-712-1435; nroupha@emory.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: This study will enroll up to 100 donor participants and up to 50 recipient participants.

Study Record Dates

• First Submitted: September 5, 2026
• First Posted: September 11, 2026
• Study Start (Estimated): December 1, 2026
• Primary Completion (Estimated): March 1, 2031
• Study Completion (Estimated): March 1, 2031
• Last Updated: September 11, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ANALYTIC CODE
• Time Frame: Data underlying each publication will become available at the time the corresponding peer-reviewed publication is first made publicly available and will remain available for at least five years thereafter.
• Access Criteria: Data will be available for sharing with qualified researchers who submit a methodologically sound proposal whose proposed use is scientifically appropriate, feasible, consistent with informed consent, and compatible with applicable privacy, institutional, and regulatory requirements. Data will be shared for purposes of reproducing or validating published analyses, conducting approved analyses, or performing individual-participant-data meta-analyses. Written proposals will be submitted to the FLU-TIDE Principal Investigator and reviewed for scientific merit, methodological soundness, feasibility, consistency with informed consent, and adequacy of privacy protections. Approved requestors will execute an Emory-approved data-use agreement, and data will be provided through a secure Emory-approved data-transfer mechanism. Requestors will be prohibited from attempting to reidentify participants or redistributing the data.

Locations

US (2)