CHOICE KERGUELEN 2 : Consequences of Longterm Confinement on Immunity in the Sub-Antarctic Islands : Follow-up of Volunteers on the Kerguelen Islands

University Hospital, Angers

Status

Enrolling

Conditions

Human Health in Extreme Conditions

Treatments

Other: hair collection

Other: urines collection

Other: stools collection

Other: blood ponction

Other: saliva collection

Study type

Observational

Funder types

Other

Identifiers

NCT07275489

2025-A02538-41 (Other Identifier)

49RC25_0439

Details and patient eligibility

About

Living for long periods in extreme environments-like Antarctic research stations or space missions-can have a significant impact on human health, especially on the immune system. Scientists have observed that people in such isolated conditions often experience more infections and a reactivation of viruses that usually stay dormant in the body, such as Herpes viruses. These changes affect both parts of the immune system: the rapid-response "innate" system and the slower, more specific "adaptive" system.

These immune disruptions may be caused by multiple stressors: ongoing psychological stress, disturbed sleep and light cycles (circadian rhythm disruption), and the challenges of living in confined, isolated, and extreme environments. While space missions and Antarctic overwintering programs have provided some insight into these issues, scientists still lack a detailed understanding of how the immune system adapts-or fails to adapt-over time in such conditions.

To help fill this gap, the CHOICE Kerguelen 2 study will follow a group of healthy young adults who will spend one year (from November 2025 to November 2026) in Port-aux-Français, a remote French research station on the Kerguelen Islands in the sub-Antarctic. These volunteers are participating in a civic service program and will be living in a highly isolated environment for the duration of their mission. The CHOICE Kerguelen study is conducted in collaboration with the French Polar Institute (IPEV).

The goal of the study is to collect and store a broad range of biological samples-including blood, saliva, stool, urine, and hair-from these volunteers at four time points during the time of their confinement on the Kerguelent Islands: tevery three months during their stay. These samples will be than analyzed to characterize the immune profiles and intestinal microbiota of the subjects assess eventual viral reactivations and stress biological markers. These analyses will allow to better understand how the immune system reacts to prolonged isolation, and to identify immune profiles that may develop under prolonged stress and limited social contact.

The long-term aim of this project is not only to improve our understanding of human immunity in extreme environments, but also to inform medical research for people living with chronic illness. By studying healthy individuals placed in physically and mentally challenging environments, scientists can better understand how stress and isolation may weaken immune defenses. The findings may one day help design new approaches to support immune health in vulnerable populations.

Enrollment

9 estimated patients

Sex

All

Ages

18+ years old

Volunteers

Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria :

healthy people aged > 18 years
Participant affiliated with or benefiting from a social security system
Participant has signed informed consent
Participant staying as an overwintering member at Kerguelen from November 2025 to November 2026
Participant included in the CELREMED research project of the University Hospital of Angers on helathy volunteers in the context of CHOICE Kerguelen 1 protocol

Exclusion Criteria:

age < 18 years
Pregnant, breastfeeding, or postpartum woman
immunocompromised people (primary immunodeficiency, HIV infection or immunosupressive treatment)
Person refusing to participate in the study
Person with a history of autoimmune disease - -Person deprived of liberty by judicial or administrative decision
Person undergoing involuntary psychiatric treatment
Person subject to a legal protection measure