{"title":"Impact factors and genetic characteristics of head lice infestation in schoolchildren: a cross-sectional study from 2018 to 2023 in central China.","authors":"Yi-Tian Fu, Yuan-Ping Deng, Yue Xie, Hui-Mei Wang, Yan-Yan Peng, Guo-Hua Liu, Xiang Wu","doi":"10.1186/s13071-025-06825-9","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Head lice (Pediculus humanus capitis) infestation is a worldwide public health concern, especially in school-aged children. However, its main impact factors and genetic characteristics remain poorly understood in China. Hence, the purpose of the study was to explore the precise association between multiple impact factors and head lice infestation, characterize the genetic variation of the head lice, and develop a sensitive and specific mitochondrial (mt) DNA duplex polymerase chain reaction (PCR) for accurately distinguishing clades A and B.</p><p><strong>Methods: </strong>A cross-sectional study was conducted in Hunan Province, central China from January 2018 to July 2023. A total of 9254 schoolchildren from 48 primary schools in each administrative region were examined for head lice. Impact factors for infestation were analyzed using the data collected by a questionnaire. The mt cytb gene sequences of head lice collected in the current study were used for sequence analysis, then were added to the global pool to conduct the phylogenetic analyses. Primers designed on the basis of this gene sequence were used in duplex PCR to diagnose head lice clades A and B by amplicon size.</p><p><strong>Results: </strong>Head lice infestation was found in 93.8% (45/48) of the primary schools included in the study. Overall, 6.8% (630/9254) of the examined schoolchildren harbored head lice, with 94.6% (596/630) being girls. A total of 2132 adult head lice were collected from 630 infested cases. The impact factors for head lice infestation included gender, school location, family situation, per capita income, study mode, and hair washing per week (p < 0.01). However, season and age were not considered as impact factors for head lice prevalence (p > 0.05). Phylogenetic analysis based on mt cytb gene sequences showed that head lice are classified into two clades (A and B), with clade B being more dominant in Hunan Province, central China. The newly developed duplex PCR was able to differentiate clades A from B in China with 100% sensitivity and specificity.</p><p><strong>Conclusions: </strong>Our findings revealed that head lice infestation is mostly associated with poverty and poor hygiene in Hunan Province, central China. It is crucial to consider the simultaneous surveillance of head lice infestation in schoolchildren in regions with low level of socioeconomic status; however, datasets from other provinces are warranted to confirm the findings. It further showed that clades A and B are common in central China and that the latter has emerged and become the dominant one.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"184"},"PeriodicalIF":3.0000,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12096793/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Parasites & Vectors","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1186/s13071-025-06825-9","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PARASITOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Head lice (Pediculus humanus capitis) infestation is a worldwide public health concern, especially in school-aged children. However, its main impact factors and genetic characteristics remain poorly understood in China. Hence, the purpose of the study was to explore the precise association between multiple impact factors and head lice infestation, characterize the genetic variation of the head lice, and develop a sensitive and specific mitochondrial (mt) DNA duplex polymerase chain reaction (PCR) for accurately distinguishing clades A and B.
Methods: A cross-sectional study was conducted in Hunan Province, central China from January 2018 to July 2023. A total of 9254 schoolchildren from 48 primary schools in each administrative region were examined for head lice. Impact factors for infestation were analyzed using the data collected by a questionnaire. The mt cytb gene sequences of head lice collected in the current study were used for sequence analysis, then were added to the global pool to conduct the phylogenetic analyses. Primers designed on the basis of this gene sequence were used in duplex PCR to diagnose head lice clades A and B by amplicon size.
Results: Head lice infestation was found in 93.8% (45/48) of the primary schools included in the study. Overall, 6.8% (630/9254) of the examined schoolchildren harbored head lice, with 94.6% (596/630) being girls. A total of 2132 adult head lice were collected from 630 infested cases. The impact factors for head lice infestation included gender, school location, family situation, per capita income, study mode, and hair washing per week (p < 0.01). However, season and age were not considered as impact factors for head lice prevalence (p > 0.05). Phylogenetic analysis based on mt cytb gene sequences showed that head lice are classified into two clades (A and B), with clade B being more dominant in Hunan Province, central China. The newly developed duplex PCR was able to differentiate clades A from B in China with 100% sensitivity and specificity.
Conclusions: Our findings revealed that head lice infestation is mostly associated with poverty and poor hygiene in Hunan Province, central China. It is crucial to consider the simultaneous surveillance of head lice infestation in schoolchildren in regions with low level of socioeconomic status; however, datasets from other provinces are warranted to confirm the findings. It further showed that clades A and B are common in central China and that the latter has emerged and become the dominant one.
期刊介绍:
Parasites & Vectors is an open access, peer-reviewed online journal dealing with the biology of parasites, parasitic diseases, intermediate hosts, vectors and vector-borne pathogens. Manuscripts published in this journal will be available to all worldwide, with no barriers to access, immediately following acceptance. However, authors retain the copyright of their material and may use it, or distribute it, as they wish.
Manuscripts on all aspects of the basic and applied biology of parasites, intermediate hosts, vectors and vector-borne pathogens will be considered. In addition to the traditional and well-established areas of science in these fields, we also aim to provide a vehicle for publication of the rapidly developing resources and technology in parasite, intermediate host and vector genomics and their impacts on biological research. We are able to publish large datasets and extensive results, frequently associated with genomic and post-genomic technologies, which are not readily accommodated in traditional journals. Manuscripts addressing broader issues, for example economics, social sciences and global climate change in relation to parasites, vectors and disease control, are also welcomed.