Microbiome-Based Risk Prediction of SARS-CoV-2 in Children and Families (PREDICOL) (PREDICOL)

Identification of Risk Predictors for SARS-CoV-2 Infection Based on the Microbiome of School-age Children and Their Family Members (PREDICOL)

The goal of this observational cohort study is to evaluate the association between gut microbiota composition, dietary patterns, lifestyle-related factors, and neurodevelopmental outcomes, as well as susceptibility to SARS-CoV-2 infection, in a predominantly school-aged population and their adult contacts (family and teachers).

This study aims to answer the following main questions:

• Are specific gut microbiota profiles and dietary patterns associated with cognitive and behavioral development in non-clinical children and adolescents?
• Can baseline gut microbiota and lifestyle-related factors be associated with susceptibility to SARS-CoV-2 infection during the pandemic period?

The cohort includes more than 900 participants recruited between November and December 2020 in Valencia, Spain, including children and adolescents (approximately 3-19 years of age), as well as their family members and teachers. The cohort is structured into two predefined subcohorts. One subcohort includes children and adolescents and focuses on neurodevelopmental outcomes. The second subcohort includes both pediatric and adult participants and is used to evaluate gut microbiota-related factors in relation to SARS-CoV-2 infection.

Study assessments include stool sample collection for gut microbiota analysis, dietary assessment using validated food frequency questionnaires, and collection of sociodemographic, clinical, anthropometric, lifestyle, and health-related information through standardized questionnaires. Cognitive and behavioral outcomes in children and adolescents are assessed using validated instruments.

The study includes an initial cross-sectional assessment followed by a longitudinal follow-up over a 17-month period. During follow-up, stool samples were collected from participants who became infected with SARS-CoV-2 at different stages of the infection. At the end of the follow-up period, biological samples and study assessments were repeated when available.

The results of this study are expected to contribute to the identification of microbial, dietary, and lifestyle-related biomarkers associated with neurodevelopment and susceptibility to infectious diseases, supporting the development of preventive and non-pharmacological public health strategies.

Study Overview

• Status: Completed
• Conditions: Heathly Subjects Susceptible to SARS-CoV-2 Infection

Detailed Description

Two predefined subcohorts were established. The first subcohort includes 407 children and adolescents and focuses on exploring associations between gut microbiota, diet, lifestyle factors, and cognitive and behavioral development in individuals without clinically diagnosed disorders. The second subcohort includes pediatric and adult participants and aims to evaluate whether baseline gut microbiota and related factors are associated with SARS-CoV-2 infection during the follow-up period.

The study follows an observational design with a baseline cross-sectional assessment and a longitudinal follow-up of 17 months. Biological samples and health-related information were collected to characterize gut microbiota profiles and to evaluate their relationship with developmental, behavioral, and infectious outcomes over time.

Cognitive and behavioral outcomes were assessed using validated instruments, including the Behavior Rating Inventory of Executive Function (BRIEF), the Strengths and Difficulties Questionnaire (SDQ), and diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). Gut microbiota composition was characterized by shotgun metagenomic sequencing of stool samples collected using standardized procedures.

Dietary intake was assessed using a validated 137-item semi-quantitative food frequency questionnaire, allowing estimation of daily intake of food groups and nutrients. Dietary quality and inflammatory potential were evaluated using the Dietary Inflammatory Index, adherence to the Mediterranean Diet, and the Spanish Healthy Eating Index.

By integrating microbiota, dietary, lifestyle, and developmental data, this study aims to identify microbial and lifestyle-related biomarkers associated with early neurodevelopmental trajectories and susceptibility to viral infections, supporting the development of preventive and non-pharmacological public health strategies.

• Study Type: Observational
• Enrollment (Actual): 932

Contacts and Locations

Study Locations

• Spain
  • Valencia, Spain
    • Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Subjects over the age of 3 who are interested in participating in the study. The study targets school-aged subjects (3-17 years old) as well as their close family members and teachers.

Description

Inclusion Criteria:

1. Be over 3 years of age.
2. Complete all questionnaires on diet, lifestyle, health, etc.
3. Ability to give written consent; in the case of minors, have the consent of a legal guardian.

Exclusion Criteria:

1. History of confirmed SARS-CoV-2 infection, positive serology (IgM/IgG).
2. NOT have any minors living with them in the study.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
perdicol; A total of 932 participants were included in this cohort, with a higher representation of minors compared to adults. Specifically, 506 (54.3%) participants were children and adolescents, while 426 (45.7) were adults. Overall, the cohort comprised 369 family units.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Relative abundance of intestinal microbial taxa associated with SARS-CoV-2 infection	Relative abundance of bacterial taxa in fecal samples determined by shotgun metagenomic sequencing and analyzed as predictors of SARS-CoV-2 infection risk. Associations between microbial features and infection status will be assessed using odds ratios and other risk estimation models.	Baseline (at enrollment).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Learning difficulties assessed by DSM-5 criteria	Learning difficulties will be evaluated according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Participants will be classified as having no learning difficulties (0 criteria endorsed), slight learning difficulties (1-2 criteria endorsed), or significant learning difficulties (≥3 criteria endorsed). Correlations between gut microbiota characteristics and DSM-5 learning difficulty classification will be evaluated.	Baseline (at enrollment)
Dietary pattern adherence score derived from principal component analysis	Dietary patterns will be identified using principal component analysis (PCA) with varimax rotation based on nutrient and food group intake data. Participants will be assigned pattern adherence scores and categorized into tertiles representing low (T1), moderate (T2), and high (T3) adherence. Associations between dietary pattern adherence and gut microbiota composition will be evaluated.	Baseline (at enrollment)
Compliance with age- and sex-specific dietary recommendations	Participants will be classified according to compliance with Recommended Dietary Allowances (RDA) established by AESAN and the Spanish Society of Community Nutrition (SENC). Intake will be categorized as compliant, below recommendations, or above recommendations. Associations between dietary compliance and gut microbiota composition will be evaluated.	Baseline (at enrollment)
Daily food group intake assessed by EPIC Food Frequency Questionnaire (grams/day)	Daily intake of 22 food groups will be estimated from food frequency questionnaire data and expressed as grams per day (g/day). Food groups will be defined according to study objectives and Spanish Agency for Food Safety and Nutrition (AESAN) classification criteria. Associations between food group intake and gut microbiota composition will be evaluated.	Baseline (at enrollment)
Daily nutrient intake assessed by EPIC Food Frequency Questionnaire (grams/day)	Dietary intake will be assessed using a validated 137-item semi-quantitative EPIC Food Frequency Questionnaire adapted for Spanish children and adolescents. Daily intake of 52 nutrients will be estimated and expressed as grams per day (g/day). Associations between nutrient intake and gut microbiota composition will be evaluated.	Baseline (at enrollment)
Executive function assessed by Behavior Rating Inventory of Executive Function (BRIEF) T-score	Executive function will be assessed using the Behavior Rating Inventory of Executive Function (BRIEF). Age- and sex-adjusted T-scores will be used. Participants will be classified as normal (T<60), subclinical impairment (T=60-64), or clinical impairment (T≥65). Correlations between gut microbiota characteristics and BRIEF T-scores will be evaluated.	Baseline (at enrollment)
Total difficulties score assessed by Strengths and Difficulties Questionnaire (SDQ)	Behavioral and emotional difficulties will be evaluated using the Strengths and Difficulties Questionnaire (SDQ). Total difficulties scores range from 0 to 40, with higher scores indicating greater behavioral problems. Participants with scores >16 will be classified as presenting behavioral difficulties. Correlations between gut microbiota characteristics and SDQ total difficulties scores will be evaluated.	Baseline (at enrollment)
Daily stress level assessed by Inventario de Estrés Cotidiano Infantil (IECI)	Daily stress will be assessed using the Inventario de Estrés Cotidiano Infantil (IECI). Total questionnaire scores will be converted to age- and sex-adjusted percentiles. Participants scoring above the 70th percentile will be classified as having elevated daily stress. Correlations between gut microbiota characteristics and IECI stress scores will be evaluated.	Baseline (at enrollment)

Collaborators and Investigators

• Sponsor: Spanish National Research Council
• Collaborators: Interdisciplinary Thematic Platform (PTI+) Global Health (CSIC)
• Investigators: Principal Investigator: Yolanda Professor Sanz, Principal Investigator, Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC)

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2020
• Primary Completion (Actual): April 30, 2022
• Study Completion (Actual): December 22, 2024

Study Registration Dates

• First Submitted: January 15, 2026
• First Submitted That Met QC Criteria: July 16, 2026
• First Posted (Actual): July 21, 2026

Study Record Updates

• Last Update Posted (Actual): July 21, 2026
• Last Update Submitted That Met QC Criteria: July 16, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: SARS-CoV-2; Diet; Gut microbiota; Metacognition; Behaviour; Learning disorders
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Neurobehavioral Manifestations; Neurodevelopmental Disorders; Communication Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Learning Disabilities; Behavior
• Other Study ID Numbers: PRE131/20

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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