A Checklist of Macronyssid Species (Mesostigmata: Macronyssidae) From Brazil

Molecular detection of Bartonella spp. in bat-associated macronyssid mites (Acari: Macronyssidae) from Southern and Southeastern Brazil

Despite the worldwide occurrence and high genetic diversity of Bartonella spp. in bats, few studies investigate their occurrence in bat-associated mites. To date, 26 species of Macronyssidae mite species have been reported from Brazil, and 15 of which were found parasitizing bats. The present study aimed to investigate the presence of Bartonella DNA in bat-associated macronyssid mites from Brazil. For this purpose, 393 macronyssid specimens were selected by convenience from the tissue bank of the Acari Collection of the Instituto Butantan (IBSP). These mites were collected from 14 different bat species in three different Brazilian States (Minas Gerais, Paraná, and Rio de Janeiro). Out of 165 mites positive in the PCR for the endogenous 18S rRNA gene, only eight were positive in the qPCR for Bartonella spp. based on the nuoG gene, and we were able to obtain two sequences base in this same gene, and one sequence based on the 16S rRNA gene. The phylogenetic inference based on the nuoG gene grouped the obtained sequences with Bartonella genotypes previously detected in bats and associated bat flies, while the phylogeny based on the 16S rRNA grouped the obtained sequence in the same clade of Bartonella genotypes previously detected in Dermanyssus gallinae. These findings suggest that macronyssid mites might be associated with the maintenance of bartonellae among bats.

Mapping the distributions of blood-sucking mites and mite-borne agents in China: a modeling study

Background

Emerging mite-borne pathogens and associated disease burdens in recent decades are raising serious public health concerns, yet their distributions and ecology remain under-investigated. We aim to describe the geographical distributions of blood-sucking mites and mite-borne agents and to assess their ecological niches in China.

Methods

We mapped 549 species of blood-sucking mites belonging to 100 genera at the county level and eight mite-associated agents detected from 36 species of blood-sucking mites in China during 1978–2020. Impacts of climatic and environmental factors on the ecology of 21 predominant vector mites and a leading pathogen, Orientia tsutsugamushi, were assessed using boosted regression tree (BRT) models, and model-predicted risks were mapped. We also estimated the model-predicted number, area and population size of affected counties for each of the 21 mite species in China.

Results

Laelaps echidninus is the leading mite species that potentially affects 744 million people, followed by La. jettmari (517 million) and Eulaelaps stabularis (452 million). Leptotrombidium scutellare is the mite species harboring the highest variety of mite-borne agents including four Rickettsia species and two viruses, followed by Eu. stabularis (2 agents), L. palpale (2) and La. echidninus (2). The top two agents that parasitize the largest number of mite species are O. tsutsugamushi (28 species) and hantavirus (8). Mammalian richness, annual mean temperature and precipitation of the driest quarter jointly determine the ecology of the mites, forming four clusters of major mite species with distinct geographic distributions. High-risk areas of O. tsutsugamushi are mainly distributed in southern and eastern coastal provinces where 71.5 million people live.

Conclusions

Ecological niches of major mite species and mite-borne pathogens are much more extensive than what have been observed, necessitating expansion of current filed surveillance.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-022-00966-0.

A dataset of distribution and diversity of blood-sucking mites in China

Mite-borne diseases, such as scrub typhus and hemorrhagic fever with renal syndrome, present an increasing global public health concern. Most of the mite-borne diseases are caused by the blood-sucking mites. To present a comprehensive understanding of the distributions and diversity of blood-sucking mites in China, we derived information from peer-reviewed journal articles, thesis publications and books related to mites in both Chinese and English between 1978 and 2020. Geographic information of blood-sucking mites' occurrence and mite species were extracted and georeferenced at the county level. Standard operating procedures were applied to remove duplicates and ensure accuracy of the data. This dataset contains 6,443 records of mite species occurrences at the county level in China. This geographical dataset provides an overview of the species diversity and wide distributions of blood-sucking mites, and can potentially be used in distribution prediction of mite species and risk assessment of mite-borne diseases in China.