Lessons from the European mpox outbreak: strengthening cohort research for future pandemic preparedness

Abstract

Background: Well-designed cohort studies are crucial for pandemic preparedness, informing evidence-based infection prevention and treatment strategies. Objectives: Following the 2022 mpox outbreak in Europe, this scoping review critically evaluates the design, implementation, and characteristics of cohort studies focusing on mpox. The aim is to inform recommendations for the Cohort Coordination Board and the COordination MEchanism for Cohorts and Trials (CoMeCT) to enhance cohort study research and improve preparedness. Sources: A comprehensive literature search was conducted in PubMed, Scopus, ClinicalTrials.gov, the European Union Clinical Trials Register, and the European Clinical Research Infrastructure Network (ECRIN) metadata repository up to December 2024. Content: Forty-nine cohorts were identified, encompassing 10 728 individuals with primary or breakthrough mpox and 34 010 individuals without mpox (vaccinated and unvaccinated). The majority of cohorts collected data prospectively (30, 63%) and were multicentre (25, 52%). The primary aims were the natural history of mpox (31, 65%); effectiveness of vaccination (15, 31%); and treatment (2, 4%). The most frequent target population was individuals at increased risk of sexually transmitted infection (18, 38%). Follow-up of participants varied widely among cohorts. Significant data heterogeneity, stemming from the inconsistent use of standardized data dictionaries, impeded data sharing and meta-analyses. Under-representation of vulnerable populations and limited biobanking further compounded these challenges. Implications: This review underscores critical gaps in the research response during the mpox outbreak. Based on these findings, we propose the following recommendations: (1) establishing and maintaining "ever-warm" cohorts of high-risk individuals during inter-epidemic periods to enable rapid data collection during future outbreaks; (2) promoting data interoperability through the development and adoption of standardized data collection tools and ontologies; (3) improving the quality of study reporting through strict adherence to relevant guidelines; and (4) strengthening European and global coordination through the establishment of collaborative research networks. Sustained investment in research infrastructure is essential for a more effective, equitable, and timely public health response to future outbreaks.

A.G. reported salary grants from VERDI and CoMeCT (101045989 and 101136531), A.J. reported EU funding to her institution (101045989 and 101136531), A.M. reported institutional grants funding his research activities (PID2022-141395OB-I00 funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU and SGR00176 grant from the Departament de Recerca i Universitats de la Generalitat de Catalunya), A.N. reported salary grant from VERDI (101045989), C.B. reported grants from DZIF, NEAT-ID, DFG as well as consulting fees, honoraria and support for attending meetings and for travel from Abbvie, Gilead, JnJ, MSD, and ViiV and a leadership role in EACS, C.V.D. reported salary grant nr. 12B1M24N from Research Fund - Flanders (FWO), Q.G. reported grants and contracts from Institut Pasteur (ANR-18-CE11-0017 and ANR-21-CE11-0003) as well as CoMeCT (101136531). All other authors declare no conflict of interest.