Temporal trends in respiratory and gastrointestinal infections at the Grand Magal of Touba: the effect of the COVID-19 pandemic

TL;DR

The study found that the prevalence of respiratory and gastrointestinal infections among pilgrims in Senegal changed during the COVID-19 pandemic, likely due to preventive measures and demographic shifts.

Contribution

The study provides new insights into how the pandemic affected pathogen prevalence in a specific cultural and geographic context.

Findings

Respiratory virus prevalence, especially rhinovirus, decreased during the pandemic, while influenza increased.

Gastrointestinal bacterial pathogens, particularly various Escherichia coli, declined during the pandemic.

Streptococcus pneumoniae and Moraxella catarrhalis infections increased during the pandemic, while S. aureus decreased.

Abstract

The COVID-19 pandemic has been associated with changes in the epidemiology of other respiratory tract and gastrointestinal Infections.

Respiratory and gastrointestinal pathogen carriage was assessed by qPCR between 2017 and 2024 in 1327 participants comprising 837 pilgrims from villages in South Senegal and 490 patients consulting for respiratory symptoms at the Mbacké health care centre near Touba.

Among pilgrims returning from the GMT, the overall prevalence of respiratory viruses significantly decreased during the pandemic years in Senegal (2020–2021). This was mostly due to rhinovirus and the prevalence of variations of endemic coronaviruses. In contrast, the prevalence of influenza viruses increased during the pandemic years. Overall, the prevalence of respiratory bacteria decreased during and after the pandemic, with the notable exception of Haemophilus spp. The prevalence of gastrointestinal bacterial pathogens decreased during the pandemic, which was mostly due to a decrease in various Escherichia coli pathotypes,.

influenza A virus was the most common virus, and its prevalence was significantly higher during and after the pandemic, while the prevalence of other respiratory viruses decreased over time from 2018 until 2024. Infections with Streptococcus pneumoniae and Moraxella catarrhalis increased during the COVID-19 period, while that of S. aureus decreased.

Significant variations in the prevalence of respiratory and gastrointestinal pathogens were observed among pilgrims participating in the GMT during the COVID-19 pandemic in Senegal. This could be due to changes in individual non-pharmaceutical preventive measures during the pandemic period as well as changes in the demographic profile of participants.