Microbial Signature of Ocean-Going Syndrome

Abstract Background and aims: During ocean-going voyages, crew members are subject to complex pressures from their living and working environment, which leads to a sub-optimal health status. Although abnormal defecation was observed during voyages, the associations between the gut microbiome and the symptoms are still unclear. Methods: Associations between the gut microbiome and the health status of 77 crew members during a 135 day-long ocean-going voyage were evaluated using shotgun metagenomics of stool samples and health questionnaires (with 24 physical and psychological indicators) taken before and after the voyage.Results: The co-appearance of symptoms e.g. abnormal defecation frequency, insomnia, shallow sleep, nausea and over-eating best described the sub-optimal health status of the majority of crew members, and we named this as ‘Ocean-Going Syndrome (OGS)’. The OGS, instead of any single symptom, has a significant effect on the gut microbiome, and it was proved to be a key factor for individual perturbation in the gut microbiome during the voyage. Co-occurrence network analysis revealed a different microbial dynamic between the OGS and non-OGS crews, and the variation of 19 bacterial species and 31 gene families were identified as microbial signature for the OGS. Moreover, using a Random Forest model, the OGS can be predicted with a high accuracy (AUC=0.91) based on 27 biomarkers from pre-voyage samples. Conclusions: Understanding associations between the gut microbiome and health status under extreme environments could help us discover potential predictors or even therapeutic targets for dysbacteriosis related diseases.