Pneumonia outbreaks due to re-emergence of Mycoplasma pneumoniae

On Nov 22, 2023, WHO released a statement regarding reported clusters of pneumonia in children in northern China.1WHOWHO statement on reported clusters of respiratory illness in children in northern China.https://www.who.int/news/item/22-11-2023-who-statement-on-reported-clusters-of-respiratory-illness-in-children-in-northern-chinaDate: Nov 22, 2023Date accessed: November 22, 2023Google Scholar Concurrently, the results of our global prospective surveillance study of Mycoplasma pneumoniae (ESGMAC MAPS study) were published, revealing the re-emergence of M pneumoniae in Europe and Asia; however, our study did not include data from China.2Meyer Sauteur PM Beeton ML on behalf of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Mycoplasma and Chlamydia Infections (ESGMAC)and the ESGMAC Mycoplasma pneumoniae Surveillance (MAPS) study groupMycoplasma pneumoniae: delayed re-emergence after COVID-19 pandemic restrictions.Lancet Microbe. 2023; (published online Nov 23)https://doi.org/10.1016/S2666-5247(23)-0Google Scholar These observations indicated that the increase in the incidence of pneumonia in China could be due to the increased circulation of known pathogens such as M pneumoniae, which causes childhood pneumonia worldwide. The following day, Chinese authorities indeed attributed this increase in incidence to the upsurge in the circulation of M pneumoniae and respiratory viruses, such as the influenza virus and respiratory syncytial virus, in the first winter season after abolishing COVID-19 restrictions.3WHOUpsurge of respiratory illnesses among children-Northern China.https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON494Date: Nov 23, 2023Date accessed: November 23, 2023Google Scholar M pneumoniae and respiratory syncytial virus are known to affect children more than adults. Based on this information, WHO recommended measures to reduce the risk of respiratory illness, which included vaccination against influenza, COVID-19, and other respiratory pathogens, as appropriate.3WHOUpsurge of respiratory illnesses among children-Northern China.https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON494Date: Nov 23, 2023Date accessed: November 23, 2023Google Scholar Currently no vaccination exists against M pneumoniae, complicating prevention. M pneumoniae infections have been largely absent globally since the introduction of COVID-19 restrictions in March, 2020, re-emerging in many countries in the northern hemisphere during the autumn of 2023.2Meyer Sauteur PM Beeton ML on behalf of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Mycoplasma and Chlamydia Infections (ESGMAC)and the ESGMAC Mycoplasma pneumoniae Surveillance (MAPS) study groupMycoplasma pneumoniae: delayed re-emergence after COVID-19 pandemic restrictions.Lancet Microbe. 2023; (published online Nov 23)https://doi.org/10.1016/S2666-5247(23)-0Google Scholar Thus, the high case numbers are not restricted to China and the re-emergence might consist of pre-existing bacterial strain lineages shared between geographically diverse regions. Macrolides are the first-line treatment for paediatric patients, as alternative antibiotics including tetracyclines and fluoroquinolones might have potential toxicities in young children. The way these pneumonia epidemics will emerge between China and the rest of the world might depend on the ability to treat cases of pneumonia due to the presence of macrolide-resistant M pneumoniae (MRMP), as over 80% of M pneumoniae detections in China have been consistently reported as MRMP.4Zhou Y Zhang Y Sheng Y Zhang L Shen Z Chen Z More complications occur in macrolide-resistant than in macrolide-sensitive Mycoplasma pneumoniae pneumonia.Antimicrob Agents Chemother. 2014; 58: 1034-1038Crossref PubMed Scopus (113) Google Scholar, 5Wang Y Xu B Wu X et al.Increased macrolide resistance rate of M3562 Mycoplasma pneumoniae correlated with macrolide usage and genotype shifting.Front Cell Infect Microbiol. 2021; 11675466Google Scholar, 6Jiang TT Sun L Wang TY et al.The clinical significance of macrolide resistance in pediatric Mycoplasma pneumoniae infection during COVID-19 pandemic.Front Cell Infect Microbiol. 2023; 131181402Crossref Scopus (1) Google Scholar Treatment failure due to MRMP is associated with serious clinical consequences in children, leading to more severe radiological findings of pulmonary disease and an increase in extrapulmonary manifestations including mucocutaneous and neurological disease.4Zhou Y Zhang Y Sheng Y Zhang L Shen Z Chen Z More complications occur in macrolide-resistant than in macrolide-sensitive Mycoplasma pneumoniae pneumonia.Antimicrob Agents Chemother. 2014; 58: 1034-1038Crossref PubMed Scopus (113) Google Scholar, 5Wang Y Xu B Wu X et al.Increased macrolide resistance rate of M3562 Mycoplasma pneumoniae correlated with macrolide usage and genotype shifting.Front Cell Infect Microbiol. 2021; 11675466Google Scholar, 6Jiang TT Sun L Wang TY et al.The clinical significance of macrolide resistance in pediatric Mycoplasma pneumoniae infection during COVID-19 pandemic.Front Cell Infect Microbiol. 2023; 131181402Crossref Scopus (1) Google Scholar Because of the high proportion of MRMP in Asia, Japan changed its prescribing policies in 2017 from macrolides to fluoroquinolones, such as tosufloxacin.7Kenri T Yamazaki T Ohya H et al.Genotyping of Mycoplasma pneumoniae strains isolated in Japan during 2019 and 2020: spread of p1 gene type 2c and 2j variant strains.Front Microbiol. 2023; 141202357Crossref PubMed Scopus (0) Google Scholar The severity of the epidemic in China, and in other countries, and the associated serious extrapulmonary complications remain uncertain considering the high rate of MRMP infections, and the answer will be evident as time progresses. Owing to these concerns, several institutes from China have now joined our global prospective surveillance network, enabling the monitoring of the magnitude and severity of re-emerging infections. We declare no competing interests. Monthly updates of the ESGMAC MAPS study are published on the ESGMAC website (https://www.escmid.org/research-projects/study-groups/study-groups-g-n/mycoplasma-and-chlamydia/esgmac-maps-study). Download .pdf (.06 MB) Help with pdf files Supplementary appendix