A Study of the Mechanisms of Infection Susceptibility Across the Life Course and the Development of an Intelligent Prevention and Control System

This multicenter, observational registry study aims to characterize host immune, genetic, and microbiome features associated with susceptibility to infection and the risk of severe infection in adults. Approximately 2,195 adults aged 18 years or older undergoing routine health examinations or health screening will be enrolled and followed prospectively for five years. Available clinical information and previously stored biological samples collected since 2019 will also be retrospectively integrated. Demographic characteristics, medical history, medication use, vaccination history, laboratory findings, infection events, treatments, hospitalizations, intensive care admissions, and clinical outcomes will be recorded. Blood, urine, stool, sputum, and nasopharyngeal or oropharyngeal samples will be collected when available to evaluate host immune responses, genetic characteristics, biomarkers, and microbial composition and function. By integrating longitudinal clinical data with biological measurements, the study seeks to identify potential biomarkers and improve infection-risk prediction beyond conventional clinical factors, thereby supporting risk stratification and the development of personalized infection-prevention strategies.

Study Overview

• Status: Not yet recruiting
• Conditions: Infectious Diseases

• Study Type: Observational
• Enrollment (Estimated): 2195

Contacts and Locations

• Study Contact: Name: Jingwen Dr Ai; Phone Number: 86+13764990804; Email: jingwenai1990@126.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Adults aged 18 years and older

Description

Inclusion Criteria:

1. Aged 18 years or older and undergoing an adult health examination or health screening at a participating center.
2. No severe organ dysfunction that substantially affects daily living, such as decompensated heart, liver, or kidney failure.
3. Able to communicate and cooperate with study procedures.
4. Willing to participate and provides informed consent in accordance with ethics committee-approved requirements.

Exclusion Criteria:

1. Declines to participate.
2. Essential clinical information required for the study is unavailable and cannot be obtained after verification.
3. Considered unsuitable for participation by the investigator; the specific reason will be documented.

Study Plan

How is the study designed?

Design Details

• Observational Models: COHORT
• Time Perspectives: PROSPECTIVE

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of the Composite Endpoint of Death or Severe Infection	Number of participants experiencing at least one component of the composite endpoint: all-cause death, infection-related death, or severe infection. Severe infection will be evaluated based on clinically documented outcomes, including infection-related hospitalization, intensive care unit admission, mechanical ventilation, or other life-threatening infection events.	From baseline to Year 5

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Overall Infection	Number and proportion of participants who experience at least one clinically documented infection, including respiratory tract infection, bloodstream infection, urinary tract infection, or another confirmed infectious disease.	From baseline to Year 5
Incidence of Respiratory Tract Infection	Number and proportion of participants who experience at least one respiratory tract infection, including upper respiratory tract infection, bronchitis, pneumonia, or another respiratory infection confirmed by clinical diagnosis or pathogen testing.	From baseline to Year 5
Incidence of Bloodstream Infection	Number and proportion of participants who experience at least one clinically documented bloodstream infection, including bacteremia, fungemia, or another bloodstream infection supported by blood culture or other pathogen testing in the presence of clinical signs of infection.	From baseline to Year 5
Incidence of Urinary Tract Infection	Number and proportion of participants who experience at least one urinary tract infection, including cystitis, pyelonephritis, or another urinary tract infection supported by clinical diagnosis, urine pathogen testing, or documented anti-infective treatment.	From baseline to Year 5
Correlation Between Gut Microbiome Alpha Diversity and Infection Episode Rate	Spearman's correlation coefficient (ρ) between baseline gut microbiome alpha diversity (Shannon index) measured from stool samples and infection episode rate (episodes/person-year) obtained from clinical records during follow-up.	From baseline to Year 5
Proportion of peripheral immune cell subset with Infection Susceptibility and Severity	Proportion of peripheral blood immune cell subsets with Infection Susceptibility and Severity	From baseline to Year 5

Collaborators and Investigators

• Sponsor: Huashan Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): December 31, 2032
• Study Completion (Estimated): December 31, 2032

Study Registration Dates

• First Submitted: October 29, 2026
• First Submitted That Met QC Criteria: November 12, 2026
• First Posted (Actual): November 13, 2026

Study Record Updates

• Last Update Posted (Actual): November 13, 2026
• Last Update Submitted That Met QC Criteria: November 12, 2026
• Last Verified: October 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Pathological Conditions, Signs and Symptoms; Communicable Diseases
• Other Study ID Numbers: KY2026-

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No