Back to search results

Observational Study on Dysbiosis and Long COVID

This observational study is looking into how changes in gut bacteria, called dysbiosis, might affect people with Long COVID. Researchers will collect stool and blood samples from 400 people: 200 who have Long COVID symptoms and 200 who do not. They want to see if people with Long COVID have less diverse gut bacteria, more of certain bacteria (Bacteroides), and lower levels of helpful substances like SCFAs, indole, and secondary bile acids. This study aims to understand how these gut changes might be linked to the severity of Long COVID symptoms, immune system issues, and problems with the gut barrier. You may be able to join if you are between 18 and 80 years old, had COVID-19 within the last 3 years, and have or do not have Long COVID symptoms.

Study design
This is an observational study involving 400 participants, divided into two groups: those with Long COVID and those without. It is not specified if the study is randomized or blinded.
What's involved
Participants will provide matched stool and blood samples. The duration of participation is not specified beyond baseline collections.
Compensation
Not stated in the trial record.
Follow-up
Participants will be followed from baseline until final values are collected.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

NCT06825819

Dysbiosis & Long COVID

Recruiting
Not specifiedAges 18–80Observational
University of Chicago
~400 participants
Updated 2026-03-02 on ClinicalTrials.gov
What's tested:Subjects with and without Long COVID

At a glance

Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
To determine whether people with long COVID exhibit microbial dysbiosis characterized by decreased bacterial diversity, overgrowth of Bacteroides taxa, and lower SCFA, indole, and secondary bile acid production with biospecimen collections
Measured over At baseline until final values

Conditions

COVID-19

Explore related trials

COVID-19 Infection

Where it's being run

1 sites across 1 states
Illinois1

Study leadership

  • Lavanya Visvabharathy, Ph.D · PRINCIPAL_INVESTIGATOR · University of Chicago

Who to contact

Lavanya Visvabharathy, Ph.D
[email protected]
773-834-5087
Email the study team

Opens a ready-to-send draft in your own email app — review before sending.

Do you actually qualify for this trial?

Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.

Check eligibility for this trial ~2 min · HIPAA-protected · delete anytime
Eligibility criteria

Inclusion

Age: 18-80
Sex: Any
Race: Any
Last COVID infection: within past 3 years, PCR- or antigen-confirmed, symptomatic (mild/moderate/severe)
COVID vaccination status: Any
Presence of long COVID symptoms (GI, cardiac, pulmonary, neuro, musculoskeletal, and/or psych): 200 with symptoms, 200 w/o symptoms as defined by SBQ-LCTM.
May or may not be doing routine endoscopy at UCM

Exclusion

Age \<18 or \>80
Last COVID infection \>3 years ago (PCR/antigen-confirmed, symptomatic)
Currently or within the last 3 months COVID+ by nasopharyngeal PCR/antigen test
Currently diagnosed with cancer
Currently pregnant (cannot take colon biopsy sample; only eligible for survey/blood \& stool collection)
Currently on biologic immunomodulatory medications
Official diagnosis of irritable bowel disease (IBD) or other chronic GI disorder
Healthy adult volunteers
Pregnant people
UCMC and UChicago employees
Staff/faculty

What this trial measures

  • To determine whether people with long COVID exhibit microbial dysbiosis characterized by decreased bacterial diversity, overgrowth of Bacteroides taxa, and lower SCFA, indole, and secondary bile acid production with biospecimen collectionsAt baseline until final values