Epidemiology of Mycoplasma pneumoniae and co-detection with other respiratory pathogens in a respiratory sentinel surveillance system in Scotland, October 2022 to May 2025

BACKGROUNDCommunity-acquired pneumonia by Mycoplasma pneumoniae is often complicated by co-infections with other respiratory pathogens.AIMWe describe through a sentinel respiratory surveillance system in Scotland, M. pneumoniae infection occurrence in patients presenting to general practitioners with acute respiratory infection (ARI) (October 2022-May 2025) and the co-detection frequency of other respiratory pathogens.METHODSUpper respiratory tract swabs from a representative community sample of 65,798 ARI patients were laboratory-tested for 10 respiratory pathogens, including M. pneumoniae. Positivity for M. pneumoniae was monitored over time. Single or multiple joint pathogen detections were assessed and stratified by demographic characteristics. Proportions hospitalised within 14 days after their M. pneumoniae positive test were determined.RESULTSOf 65,798 patients (40,158 female, 25,534 male, 106 sex unknown; median age: 35 years, interquartile range (IQR): 17-59), 3,031 (4.6%) were M. pneumoniae positive (1,686 female, 1,340 male, five sex unknown; median age: 18 years, IQR: 9-39). Positivity was elevated in October 2023-October 2024, particularly in 5-14-year-olds, and peaked at 47.7% (31/65) in week 1, 2024. Among M. pneumoniae cases viably tested for all pathogens, 26.0% (728/2,799) had co-detections of another pathogen, with rates in 0-4-year-olds (61.3%; 122/199) and 5-14-year-olds (31.3%, 321/1,024) reflecting those reported elsewhere in hospitalised paediatric cases. Co-detections involving rhinovirus (47.5%; 346/728) predominated, otherwise varying by pathogen and age. Of 3,031 M. pneumoniae cases, 1.8% (n = 55) were admitted.CONCLUSIONSentinel surveillance of respiratory pathogens in the community was helpful to characterise an M. pneumoniae epidemic, revealing frequent respiratory-pathogen co-detections in ≤ 14-year-olds, as prior reported in hospitalised M. pneumoniae paediatric cases.