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Eosinophilic meningitis due to rat lungworm, Angiostrongylus cantonensis, is a global public health concern. Human cases and outbreaks have occurred in the new endemic areas, including South America and Spain. The growing genetic data of A. cantonensis provides a unique opportunity to explore the global spread pattern of the parasite. Eight more mitochondrial (mt) genomes were sequenced by the present study. The phylogeny of A. cantonensis by Bayesian inference showed six clades (I–VI) determined by network analysis. A total of 554 mt genomes or fragments, which represented 1472 specimens of rat lungworms globally, were used in the present study. We characterized the gene types by mapping a variety of mt gene fragments to the known complete mt genomes. Six more clades (I2, II2, III2, V2, VII and VIII) were determined by network analysis in the phylogenies of cox1 and cytb genes. The global distribution of gene types was visualized. It was found that the haplotype diversity of A. cantonensis in Southeast and East Asia was significantly higher than that in other regions. The majority (78/81) of samples beyond Southeast and East Asia belongs to Clade II. The new world showed a higher diversity of Clade II in contrast with the Pacific. We speculate that rat lungworm was introduced from Southeast Asia rather than the Pacific. Therefore, systematic research should be conducted on rat lungworm at a global level in order to reveal the scenarios of spread.

Yukang Dong,1,* Yingying He,1,* Xia Zhou,1 Xia Lv,1 Jia Huang,1 Yaqi Li,1 Xin Qian,2 Fangfang Hu,3 Jiaying Zhu1 1Department of Emergency, Guizhou Provincial People’s Hospital, Guiyang, People’s Republic of China; 2Department of Pharmacy, Guizhou Provincial People’s Hospital, Guiyang, People’s Republic of China; 3Department of Clinical Laboratory, Guizhou Provincial People’s Hospital, Guiyang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiaying Zhu, Email miraclezhujy@163.comBackground: Mycoplasma hominis meningitis is a rare postoperative complication of neurosurgery. Accurate and early diagnosis of M. hominis remains challenging because of the limitations of traditional detection methods. Metagenomic next-generation sequencing (mNGS) is an advanced technique with high sensitivity and specificity for identifying infectious pathogens; however, its application in diagnosing M. hominis meningitis has not been widely studied.Case Presentation: We report the case of a 61-year-old man who presented with fever and headache after neurosurgical treatment for a cerebral hemorrhage. Empiric antibiotic therapy was ineffective. Traditional culture of pathogens and serological testing yielded negative results, but M. hominis was detected in the cerebrospinal fluid by mNGS. After further verification by polymerase chain reaction (PCR), the patient’s clinical treatment was adjusted accordingly. With targeted antibiotic intervention, the patient’s symptoms were effectively alleviated, and clinical indicators returned to normal levels. Furthermore, the abundance of M. hominis decreased significantly compared to the initial mNGS reading after targeted treatment, indicating that the infection caused by M. hominis was effectively controlled.Conclusion: Using mNGS, we found that M. hominis may be a candidate causative agent of meningitis. The technique also has the advantage of timeliness and accuracy that traditional cultures cannot achieve. A combination of mNGS with PCR is recommended to identify pathogens in the early stages of infectious diseases to administer targeted clinical medication.Keywords: Mycoplasma hominis, meningitis, metagenomic next-generation sequencing, cerebrospinal fluid, case report