Commentary on “Gastrointestinal illness among attendees of the FIFA Football World Cup 2022 in Qatar”

Dear Editor,

We read with great interest the article by Shams et al. [1] published in IJID Regions, which investigated the incidence and etiology of gastrointestinal (GI) illness among attendees of the Fédération Internationale de Football Association World Cup 2022 in Qatar. The study provides valuable epidemiologic insights into infectious disease transmission in mass gathering events (MGEs). However, to improve the reporting quality the article, we have some constructive points to enhance the robustness of the findings and their implications for future MGEs.

Surveillance and case definition limitations

The study relies on passive surveillance systems and self-reported symptoms, which may introduce reporting bias and underestimation of true incidence rates. Passive surveillance often under-captures cases because of asymptomatic infections or mild illnesses not requiring medical attention [2]. The absence of active case-finding measures, such as systematic sampling or stool culture confirmation, limits the precision of the reported prevalence. Moreover, the case definition used to classify GI illness is not sufficiently detailed regarding symptom duration and severity. Given that various enteric pathogens cause a spectrum of symptoms, an imprecise case definition may have led to misclassification biases.

Etiologic diagnosis and pathogen-specific data

Although the study identifies major pathogens responsible for GI illness, including Escherichia coli, Salmonella spp., and Norovirus, the diagnostic approach appears to be largely reliant on syndromic surveillance rather than comprehensive molecular or culture-based testing. The use of polymerase chain reaction–based diagnostics or metagenomics sequencing could have improved the identification of co-infections and rare pathogens [3]. Furthermore, antimicrobial resistance profiling of bacterial isolates would have been valuable in assessing the public health risk posed by drug-resistant strains circulating during the event [4].

Environmental and foodborne transmission pathways

The study suggests potential foodborne transmission as a significant contributor to GI illness but lacks an in-depth analysis of food safety measures implemented during the event. Given the high volume of international attendees consuming food from various sources, including vendors and official catering services, a detailed assessment of food hygiene standards and possible contamination points should have been included. In addition, water quality monitoring, especially for bottled and tap water, could have provided critical insights into non-foodborne transmission routes.

Confounding factors and regional epidemiology

The authors mention climatic conditions as a possible factor influencing the incidence of GI illness but do not account for preexisting regional epidemiologic data on enteric infections. The Middle East and North Africa region have a distinct burden of enteric pathogens, with varying seasonal trends [5]. A comparative analysis with historical data on GI infections in Qatar and neighboring countries during similar climatic conditions would have strengthened the study's conclusions.

Implications for future mass gatherings and policy recommendations

Although the study provides broad public health recommendations, a more structured risk assessment framework, such as incorporating the World Health Organization mass gathering risk assessment tools, could have been beneficial. Lessons from past MGEs, including the Hajj pilgrimage and the Olympics, should be systematically compared to identify best practices for GI illness prevention and response.

In conclusion, Shams et al. [1] offer important epidemiologic insights into GI illness during the Fédération Internationale de Football Association World Cup 2022; however, methodological refinements and a more comprehensive approach to pathogen detection, environmental risk assessment, and surveillance strategies would have strengthened the study's public health impact. Future research should integrate advanced molecular diagnostics, food and water safety assessments, and comparative epidemiologic analyses to enhance preparedness for upcoming MGEs.

Declarations of competing interest

The authors have no competing interests to declare.