Publications by authors named "Xian-guo Guo"

Article Synopsis
  • Chiggers are the only known carriers of the scrub typhus pathogen, and a study in southwest China (2001-2022) focused on their infestation in the large-eared field mouse for the first time, collecting 933 chiggers from 501 mice across various species.
  • Adult mice had significantly higher chigger infestation rates (38.28%) and abundance (5.11 mites/mouse) compared to juvenile mice (12.63%, 0.97), indicating age-related susceptibility, while nutritional status also influenced infestation levels.
  • Chigger diversity increased with altitude, and key environmental factors like temperature and humidity were found to positively affect chigger abundance, while altitude showed a negative correlation, suggesting that elevations impact ch
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  • * Collecting and preparing specimens of these ectoparasites is critical for studying their classification, ecology, and epidemiology, as well as for monitoring disease vectors.
  • * The protocol details methods for on-site collection, fixation, and identification of ectoparasites, along with indices for monitoring host density and infestation levels, providing a thorough framework for research and control efforts.
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Chiggers (chigger mites) are a group of tiny arthropods, and they are the exclusive vector of (Ot), the causative agent of scrub typhus (tsutsugamushi disease). Dehong Prefecture in Yunnan Province of southwest China is located on the China-Myanmar border and is an important focus of scrub typhus. Based on the field surveys in Dehong between 2008 and 2022, the present paper reports the infestation and ecological distribution of chiggers on the body surface of rodents and other sympatric small mammals (shrews, tree shrews, etc.

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Article Synopsis
  • A study from Southwest China (2001-2022) found that a species of chigger mite, known to transmit scrub typhus, infested a wide range of small mammals, particularly rodents.
  • A total of 2,161 mites were identified from 218 small mammal hosts, with the Asian house rat being the most common host, making up nearly 50% of the findings.
  • The study revealed that the susceptibility to mite infestation varied significantly among different small mammals and was influenced by environmental factors like altitude and latitude, suggesting that these mites could increase the risk of scrub typhus transmission.
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Scrub typhus may be one of the world's most prevalent, neglected and serious, but easily treatable, febrile diseases. It has become a significant potential threat to public health in China. In this study we used national disease surveillance data to analyze the incidence and spatial-temporal distribution of scrub typhus in mainland China during 1952-1989 and 2006-2018.

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Chiggers are common ectoparasites and the exclusive vector of scrub typhus. Based on previous investigations from a unique geographical area in Yunnan Province of southwest China, the Three Parallel Rivers Area, we retrospectively studied the species diversity and related ecology of chiggers on rodents and other small mammals. A very high species diversity of 120 chigger species was identified.

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As a group of ectoparasites, chiggers (larvae of chigger mites) are the exclusive vector of scrub typhus (tsutsugamushi disease). Rodents are the most important hosts of chiggers. The Anderson's niviventer rat, Niviventer andersoni, is an endemic species of rodent in China.

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Article Synopsis
  • * A total of 6,557 chiggers were collected, with Leptotrombidium cangjiangense, Neotrombicula japonica, and Ascoschoengastia sifanga being the most common species, and three species identified as primary scrub typhus vectors.
  • * The study found that the abundance of chiggers varied in different environments, showing a log-normal distribution pattern, and indicated that the presence of chiggers on these
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  • - Leptotrombidium scutellare is a significant mite vector for diseases like scrub typhus and hemorrhagic fever in China, but data on its impact on human health is limited.
  • - Researchers used 21 years of field data to create ecological models predicting the distribution of L. scutellare based on environmental factors such as climate and elevation, revealing a trend of habitat reduction due to human activity.
  • - Findings indicate that while L. scutellare is prevalent in high-elevation areas of Yunnan, its presence correlates strongly with the incidence of hemorrhagic fever, suggesting climate change may reduce disease risk by pushing this mite to higher elevations.
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  • Chigger mites are important ectoparasites that act as the exclusive vectors for scrub typhus and were studied in two sibling rodent species, the South China field mouse and the Lantsang field mouse.
  • Field research from 2001 to 2015 in southwest China found 42 chigger species, with 36 on the South China field mouse and 11 on the Lantsang field mouse, indicating a significant difference in species composition.
  • The overall chigger intensity was higher in the South China field mouse, and the study revealed a log-normal distribution pattern in species abundance, along with sex-based differences in chigger infestation between the two rodent species.
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Chigger mites are the exclusive vector of scrub typhus. Based on field investigations of 91 survey sites in 5 provincial regions of Southwest China, this paper reported variations of chigger infestation on the oriental house rat () along various environmental gradients. A total of 149 chigger species were identified from 2919 in the 5 provincial regions, and (a major vector of scrub typhus in China) was the first dominant chigger species, followed by and .

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  • Gamasid mites can cause health issues in humans and are known vectors for certain diseases; studying them in biodiversity hotspots like the Three Parallel Rivers Area in China is important.
  • The research utilized various diversity indices to analyze the community structure of gamasid mites collected from small mammal hosts at different elevations.
  • A total of 26,048 gamasid mites were identified, with notable peaks in species richness and diversity occurring at specific altitude ranges, showing significant differences based on the host species and elevation.
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  • A long-term study in Southwest China (2001-2019) investigated chigger mite infestations in the large Chinese vole, collecting over 52,000 chiggers from 2,661 voles, revealing high species diversity with 185 identified species.
  • The study found a high overall infestation rate (53.96%) and mean intensity, with male voles hosting more chiggers than females.
  • Dominant chigger species exhibited aggregated distribution and strong associations with each other, and the research suggested that many chigger species might have been overlooked during the sampling process, estimating a total of 223 species in the region.
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The Chinese mole shrew, Anourosorex squamipes Milne-Edwards, 1872, is a common species of insectivorous mammal in Southwest China. Based on field investigations between 2001 and 2019, the present study reports the infestation of chiggers (larvae of chigger mites) on the shrew in Southwest China and certain ecology parameters for the first time. A total of 3169 chiggers were collected from 1694 A.

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Ticks are deemed to be second only to mosquitoes as the most common vector of human infectious diseases worldwide that give rise to human and animal diseases and economic losses to livestock production. Our understanding of the phylogenetic analysis between tick lineages has been restricted by the phylogenetic markers of individual genes. Genomic data research could help advance our understanding of phylogenetic analysis and molecular evolution.

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Article Synopsis
  • Scrub typhus is an infectious disease studied in Yunnan from 2006 to 2017, with a focus on its characteristics for better public health measures.
  • A total of 27,838 cases were reported, with a slight female predominance and most affected individuals being farmers and children under 5 years old.
  • The study revealed a significant rise in cases over the years, particularly in 2017, and highlighted the regions of Baoshan and Lincang as key areas for surveillance and public education initiatives.
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Based on a long-term field investigation on chigger mites in southwest China from 2001 to 2019, the present study analyzed the infestation and distribution of chigger mites on the Chevrieri's field mouse () in the region. A total of 12,516 individuals of chigger mites were collected from 1981 mice, and 12,281 chiggers were identified as 107 species, 11 genera and 3 subfamilies in 2 families, which revealed a high species diversity of the mites on mice. Of 1981 mice, 633 ones were infested with chiggers with a relatively high overall prevalence (  = 31.

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Based on the field investigations in 91 investigation sites (counties) in southwest China between 2001 and 2019, the present paper reported the chigger mites on A. agrarius mice in southwest China for the first time by using a series of statistical methods. From 715 striped field mice captured in 28 of 91 investigated sites, only 255 chiggers were collected, and they were identified as 14 species, 6 genera in 3 subfamilies under 2 families.

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A 12-month consecutive investigation was made at Jingha village in southern Yunnan of southwest China from April 2016 to March 2017. A total of 2053 Indochinese forest rats ( Blyth, 1860) were captured and examined, which account for 84.69% (2053/2424) of all the animal hosts (rodents and other small mammals) at the investigation site.

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This paper is to illustrate the infestation and related ecological characteristics of chigger mites on the Asian house rat (Rattus tanezumi). A total of 17,221 chigger mites were collected from 2,761 R. tanezumi rats, and then identified as 131 species and 19 genera in 2 families.

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Background: The typical single-chromosome mitochondrial (mt) genome of animals has fragmented into multiple minichromosomes in the lineage Mitodivisia, which contains most of the parasitic lice of eutherian mammals. These parasitic lice differ from each other even among congeneric species in mt karyotype, i.e.

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Leptotrombidium scutellare is one of the 6 main vectors of scrub typhus in China. It has been found in more than 15 provinces of China. Especially in Yunnan, it was found to be mainly distributed in some mountainous areas with high altitude, low temperature and low precipitation.

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(1) Background: As a species of gamasid mite, the tropical rat mite () is a common ectoparasite on rodents and some other small mammals. Besides stinging humans to cause dermatitis, can be a vector of rickettsia pox and a potential vector of hemorrhagic fever with renal syndrome (HFRS). (2) Objective: The present study was conducted to understand the host selection of on different animal hosts and the distribution in different environmental gradients in Yunnan Province of Southwest China.

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The chigger mite Leptotrombidium sialkotense is one of the 6 main vectors of scrub typhus in China. Before present study, L. sialkotense was found in some parts of Hunan province, China with a narrow geographical distribution.

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This article reviews Leptotrombidium deliense, including its discovery and nomenclature, morphological features and identification, life cycle, ecology, relationship with diseases, chromosomes and artificial cultivation. The first record of L. deliense was early in 1922 by Walch.

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