Objective To formulate a catalogue of alien vectors and pathogenic organisms for early warning and effective prevention of alien species invasion. Methods The authors searched literature, online databases, and published catalogues for alien vectors and pathogens that can seriously threaten the health of human and animals and agricultural and ecological security. They were evaluated for the risk of invasion to China by using a suitable habitat prediction model and a comprehensive evaluation system of multiple indicators. Candidate species with the potential of invasion were included in this catalogue. Results A total of 304 alien species were screened out and listed in this catalogue for China, including 69 vectors and 235 pathogenic organisms. Among them, 275 species (47 vectors and 228 pathogens) had high probability of invading China. Conclusion This catalogue can be used as an early warning directory to prevent alien vectors and pathogenic organisms from invading China, which provides a reference for relevant departments to formulate preventive management strategies and measures.

Objective To determine the current and future suitable areas of Elizabethkingia anophelis, and to provide a reference for preventing its outbreak and spread in China. Methods With 21 pieces of information on the geographical distribution of E. anophelis and data on 56 climatic factors, a MaxEnt model was used to estimate the suitable areas of E. anophelis in the world and China. R 4.2.2 software was used to adjust model parameters, and construct the receiver operating characteristic curve. The area under the curve was calculated to evaluate the accuracy of the model. The results were visualized using ArcGIS 10.5 software. Results Annual precipitation (bio12, 27.0%) and the minimum temperature in January (tmin01, 22.2%) contributed most to the distribution of E. anophelis. Under current climatic conditions, the highly suitable areas for E. anophelis were mainly distributed in the southeastern United States, northern South America, western Europe, central Africa, and parts of southeastern Asia; in China, they were mainly distributed in the wet regions south of the Qinling-Huaihe Line. Under future climatic conditions, climate changes of varying intensities generally promoted the suitable areas of E. anophelis in the world and China, especially under high radiative forcing. Conclusions There are large suitable areas for E. anophelis in the world and China under both current and future climate conditions, which are expected to be promoted with the change of climate in the future. Authorities should take measures to control greenhouse gas emissions to limit the increase of E. anophelis’ suitable areas. Provinces with its highly suitable areas should strengthen surveillance, risk assessment and response.

In 2021, the national surveillance of rodent-borne pathogens of disease vectors had been started up, and a total of 123 prefectures were selected as national surveillance sites. Sampling was completed at 95 surveillance sites. A total of 17 910 rodent specimens were collected, and 16 891 of them were tested. The completion rate of pathogen detection was 94.31%. The overall infection rate of eight monitored rodent-borne pathogens around China was 2.43% (407/16 716) for Hantavirus, 0.02% (4/16 154) for Dabie bandavirus (i.e., severe fever with thrombocytopenia syndrome virus), 5.75% (624/10 850) for Leptospira interrogans, 0.11% (5/4 470) for Rickettsia mooseri, 0.05% (5/10 790) for Orientia tsutsugamushi, 2.39% (75/3 136) for Bartonella, and 0.04% (2/5 075) for Anaplasma phagocytophilum. Francisella tularensis was not detected. More than ten species of rodents were found to be infected with different pathogens in 18 provinces across China. The infection rates of pathogens in rodents in southern regions were relatively high, and the positive rates of pathogens carried by various rodents differed. Rattus norvegicus and Apodemus agrarius were the species in which the most pathogens were detected.

Objective To predict the potential distribution of Euglandina rosea in China under current and future climatic conditions via an optimized maximum entropy (MaxEnt) model, and to provide a theoretical basis for the prevention and control of invasion of E. rosea in China. Methods The global occurrence records of E. rosea were collected and screened using ENMtool. Maxent 3.4.1 and GraphPad Prism 8 were used to screen environmental variables according to the contribution rate of environmental variables, the jackknife method, and the correlation analysis of variables. The "kuenm" package was run in R 4.0.4 software to calculate and adjust the model parameters by means of regularization multipliers and feature combinations. The optimized MaxEnt model was used to predict the potential distribution of E. rosea in China under current and future climate scenarios. ArcGIS 10.7 was used to process the results and map the images. Results A total of 780 E. rosea occurrence records were identified, and four environmental variables were used to construct the MaxEnt model. The area under the curve (AUC) of the model was 0.963. The most influential environmental factors on the distribution of E. rosea were precipitation of the driest quarter and the highest temperature in February. The MaxEnt model predicted that the current potential areas of E. rosea were distributed in the southeast of China, concentrated in Fujian province, Guangdong province, and central Guangxi Zhuang Autonomous Region. It would gradually expand northward to Hunan province, Jiangxi province, central Anhui province, eastern Hubei province, and some areas of Zhejiang province in the future. Conclusions E. rosea has potential distribution in China. With global warming, its potential habitat areas will gradually expand, while at lower latitudes in the southeast they will slightly shrink. As a result, the overall center of potential areas shifts northward.

Objective To establish a duplex droplet digital polymerase chain reaction (ddPCR) detection method for Japanese encephalitis virus (JEV) and West Nile virus (WNV). Methods Based on the designed primers and probes of JEV and WNV, a duplex ddPCR detection system for JEV and WNV was established. Its sensitivity, specificity, and repeatability were explored. The sensitivity was compared with the number of cycles required for the fluorescent signal to cross the threshold in each reaction tube of dual quantitative PCR. Results The detection sensitivity of the duplex ddPCR detection system could reach 10 ² copies/μl for both JEV and WNV, with good specificity and repeatability. No cross-reactivity was observed with the Dengue virus, Chikungunya virus, Zika virus, Tick-borne encephalitis virus, and human genome. Conclusion The established duplex ddPCR method shows high sensitivity and specificity for JEV and WNV detection, which provides a solution for detection for the two viruses in different scenarios.

Objective: To investigate the density distribution of Aedes mosquitoes in different habitats and seasonal fluctuation in Hangzhou, Zhejiang Province, China from 2017 to 2021, so as to provide a scientific basis for effective prevention and control, risk assessment, and early warning of dengue fever. Methods: According to the National Vector Surveillance Implementation Plan and the Zhejiang Provincial Vector Surveillance Plan, Aedes mosquitoes were monitored in 15 districts (counties and cities) in Hangzhou. Adult mosquitoes were monitored using the double-layered mosquito net method, and larvae were monitored using the Breteau index (BI) method. The surveillance time was set during April to November. The mosquito surveillance data of the 15 districts (counties and cities) were collected. Excel 2019 software was used for data analysis. The net trap index, BI, and container index (CI) were calculated. Categorical data were compared using the Chi-squared test. One-way analysis of variance was used for quantitative data. Results: From 2017 to 2021, the density of Ae. albopictus in Hangzhou by the double-layered mosquito net method was 2.54 mosquitoes/net·h, and no Ae. aegypti mosquitoes were captured. The density of adult mosquitoes was lowest in 2017 and highest in 2020. There was a statistical difference in the net trap index between different years (F=5.117, P=0.017). The seasonal distribution generally presented a bimodal pattern, with the peaks of mosquito densities mainly in July and October. The average BI from 2017 to 2021 was 9.18, and the peak period of the BI was during May to October. The CI showed that Ae. albopictus larvae were distributed in all kinds of water bodies. The CI differed statistically between different water bodies in the same year (all P < 0.001) and between different years in the same water body (all P < 0.001). Conclusions: Ae. albopictus density was high in Hangzhou, indicating a risk of dengue fever outbreaks and regional epidemics. It is recommended that the counties (cities, districts) take timely mosquito control measures according to the density, distribution, and seasonal fluctuation of mosquitoes.

Objective: To analyze the species, composition, density, distribution, and seasonal fluctuation of flies in Fengxian District, Shanghai, China, so as to provide a basis for the prevention and control of flies in Fengxian District. Methods: The fly surveillance data in Fengxian District, Shanghai from 2011 to 2021 were collected, and Excel 2013 was used to summarize and analyze of the data. The Kolmogorov-Smirnov test was used to compare the density of flies in different habitats. Results: From 2011 to 2016, there was no significant change in the population density of flies in Fengxian District, ranging from 0.50 to 1.02 flies per cage of average annual density. In 2017 and 2018, the density of flies (1.76 and 5.25 flies per cage, respectively) increased significantly, by 70.87% and 409.71%, respectively, compared with 1.03 flies per cage in 2015. The fly density decreased year by year in 2019 and 2020, and increased in 2021, second only to the peak density in 2018. A total of 2 996 adult flies were captured, with an average density of 2.02 flies per cage. Muscina stabulans was the main species (accounting for 31.38%), followed by Boettcherisca peregrina (accounting for 28.64%). The flies density in large-scale green belts was highest with 2.32 flies per cage. The density of flies reached its peak in June, dropped sharply from July to August, and steadily decreased from September to November. Conclusions: There are more flies in large-scale green belts of Fengxian District, and the fly density peaks in June. The critical period to prevent fly-borne diseases is before June. Relevant departments in Fengxian District should raise and strengthen awareness of fly control. The environment management of large-scale green belt should be strengthened to reduce the breeding environment of flies.

Objective To investigate the level, trend, and epidemiological characteristics of scrub typhus in Changzhou, China, and to provide a basis for prevention and control of the disease. Methods The reported data of scrub typhus in Changzhou from January 1, 2012 to December 31, 2021 were collected from the China Information System for Disease Control and Prevention. We analyzed the incidence of the disease and described the regional, temporal, and population distribution characteristics of scrub typhus using descriptive epidemiology method. Results From 2012 to 2021, a total of 149 cases were reported in Changzhou, with a median annual reported incidence rate of 0.28/100 000, with the highest reported incidence rate of 0.74/100 000 in 2015 and the lowest rate of 0.04/100 000 in 2012. Cases were reported in all districts of Changzhou, with the top three being Wujin district (60, 40.27%), Xinbei district (34, 22.82%), and Liyang city (20, 13.42%). Most cases were reported between October and November in farmers, household workers, and unemployed persons, and in persons aged 45-69 years. Conclusions Scrub typhus surveillance should be strengthened, medical personnel should be trained to improve the diagnosis of scrub typhus, and health education for high-risk populations should be carried out, in order to prevent and control the occurrence and prevalence of scrub typhus.

Objective To investigate the species and prevalence of viruses carried by sandfly specimens in Wuxiang county, Shanxi province, China. Methods Sandfly specimens were collected in Wuxiang county, Shanxi province in June 2018, and virus isolation was conducted using two cell lines of golden hamster kidney cells (BHK-21 cells) and Aedes albopictus egg cells (C6/36 cells) preserved in the laboratory. The positive isolate was subjected to viral RNA extraction and cDNA library preparation, followed by viral gene amplification, nucleotide sequence determination, and phylogenetic analysis. Results The SXWX1816-2 strain caused cytopathic effects in mammalian cells (BHK-21 cells), but no cytopathic effect in insect cells (C6/36 cells). The results of nucleotide sequence determination and analysis of the virus genome showed that the lengths of nucleotide sequences in the coding region of M and S genes of the virus were 4 089 and 1 611 nt; the results of nucleotide and amino acid sequence homology and phylogenetic analysis of M and S genes of the virus showed that the SXWX1816-2 strain belonged to the Phlebovirus genus from the Phenuiviridae family, which shared the highest homology and closest phylogenetic relationship with Wuxiang virus (WUXV) previously isolated in China. Conclusions This study clarifies the taxonomic status of the virus (SXWX1816-2) isolated from natural sandflies in China. The results provide important basic data for the research on viruses carried by blood-sucking insects in China, especially the virus carried and transmitted by sandflies.

Objective To establish the susceptibility baseline of Musca domestica to pyrethroid insecticides, and to analyze the knockdown resistance gene polymorphism in some wild populations of M. domestica in Henan province, China. Methods The susceptible strain of M. domestica was a laboratory population that had not been exposed to any insecticides. The wild populations were collected in Kaifeng, Anyang, Nanyang, Zhumadian, and Hebi cities in 2019-2021. Topical application method was used to determine the median lethal dose (LD ₅₀) of permethrin, deltamethrin, and beta-cypermethrin in female adult flies. Allele-specific polymerase chain reaction (AS-PCR) was used to determine the genotypes and mutation rates of knockdown resistance genes. Spearman correlation analysis was used to test the correlation between mutation rate and LD ₅₀. DNA sequencing was used to verified the results of AS-PCR. Results The LD ₅₀ of permethrin, deltamethrin, and beta-cypermethrin was 0.151 0, 0.077 2, and 0.166 6 μg/♀ in the susceptible strain, 0.321 6, 0.130 6, and 2.235 4 μg/♀ in Kaifeng population, 0.867 7, 0.459 2, and 1.591 6 μg/♀ in Anyang population, 5.173 7, 1.037 2, and 0.416 1 μg/♀ in Nanyang population, 0.634 1, 0.108 2, and 0.262 4 μg/♀ in Zhumadian population, and 2.745 0, 1.102 9, and 2.556 0 μg/♀ in Hebi population, respectively. Only one genotype, i.e. sensitive homozygote, was detected in the susceptible strain. Five genotypes were detected in the wild populations, including sensitive homozygote (L/L), sensitive/1014F heterozygote (L/F), sensitive/1014H heterozygote (L/H), 1014F/1014H heterozygote (F/H), and 1014H homozygote (H/H). Mutation rates in the wild populations were 14.84%, 17.97%, 13.28%, 10.16%, and 20.31%, respectively. The correlation test showed that the resistance to beta-cypermethrin was related to L1014H mutation. Five genotypes from 130 M. domestica samples were sequenced, and the accuracy of AS-PCR results was 79.23%. Conclusions The susceptibility baseline of M. domestica to pyrethroid insecticides is established in Henan, and this baseline can be used as a reference value for insecticide resistance monitoring. AS-PCR can be used for routine monitoring of resistance genes in M. domestica.

Objective To investigate the genetic diversity, genetic differentiation, and phylogenetic relationship of Culex pipiens pallens populations in Shangdong, China. Methods Cx. pipiens pallens populations were collected in Heze, Dezhou, Liaocheng, Qingdao, Yantai, and Rizhao, Shandong province from September 2020 to September 2022. Genomic DNA was extracted from a single female adult mosquito. The mitochondrial cytochrome c oxidase subunit Ⅰ (mtDNA-COⅠ) gene sequences were amplified by polymerase chain reaction and sequenced afterwards. The acquired sequences were compared with those in the Basic Local Alignment Search Tool on the GenBank. BioEdit 7.0 was used to compare and analyze the sequencing results. DnaSP v6 was used to analyze the genetic diversity of populations. Arlequin 3.5 was used to calculate the genetic differentiation coefficient and gene flow of populations. PopART 1.7 was used to construct the haplotype network (TCS network). Results A total of 423 sequences of 603 bp were obtained from 6 Cx. pipiens pallens populations in Shandong province. The average content of A+T bases was 69.2%, which was consistent with the AT bias of mitochondrial DNA. There were eight haplotypes in the haplotype analysis, of which haplotype H01 was the dominant haplotype. The results of mtDNA-COⅠ sequence analysis showed that the population had rich genetic diversity. The results of molecular variance analysis indicated that the genetic differentiation of Cx. pipiens pallens mainly came from within the population; there was some genetic differentiation among some populations. The results of neutrality test showed that the populations of Cx. pipiens pallens in Liaocheng and Heze experienced expansion recently. Conclusions The mtDNA-COⅠ gene can be used as a molecular marker to study the genetic diversity of Cx. pipiens pallens populations. The genetic development of Qingdao population is special compared with other geographical populations.

Objective To analyze the epidemiological characteristics of hemorrhagic fever with renal syndrome (HFRS) in China from 2006 to 2021, to investigate the influence of non-pharmaceutical intervention against coronavirus disease 2019 (COVID-19) on HFRS prevalence, and to provide a scientific basis for the subsequent formulation of relevant policies. Methods Descriptive epidemiological methods were utilized to statistically analyze the epidemiological characteristics of HFRS in China from 2006 to 2021. The data of HFRS cases from 2006 to 2019 were used to establish an autoregressive integrated moving average (ARIMA) model to predict the number of HFRS cases in 2020-2021, and the predicted values were compared with the actual observed values. Results The number of HFRS cases in China was relatively stable in 2006-2021, and the number of deaths were significantly reduced. HFRS had obvious seasonality, with two peaks of incidence in a year, i.e., May-June and November. The number of cases in northeast China decreased, but the affected areas in the whole country expanded, and some areas were still at risk of outbreak. The number of male cases was significantly higher than that of female cases. The peak age group of onset was 35-49 years for males and 45-59 years for females, and there was a significant difference in the age composition between males and females ( χ ²=2 802.807, P<0.001). Farmers were the main affected population, accounting for more than half of the total cases. The seasonal ARIMA model was established by fitting the data of HFRS cases from 2006 to 2019 with R 4.0.4 software, which was (2,0,2)(1,1,0) ₁₂ and was well fitted. The actual observed value of HFRS cases in 2020-2021 was close to the predicted value, within its 95% confidence interval. Conclusion HFRS is an important public health problem in China and the overall trend of its prevalence is relatively stable. It is necessary to strengthen the surveillance and implement more accurate prevention and control measures. The measures for COVID-19 prevention and control in China have no significant impact on the prevalence of HFRS during 2020-2021.

Objective: To investigate the rodents species, density, and pathogens they carry in Zunyi, Guizhou Province, China. Methods: A total of 70 sampling points were set in 14 counties/districts of Zunyi, with five points in the east, south, west, north, and center of each county/district. Small mammals were monitored through night trapping in Zunyi from October 2021 to October 2022, followed by species identification and pathogen detection. Excel 2021 was used for data organization. SPSS 26.0 was used to analyze the density, species, and pathogen-carrying status of small mammals through rate or constituent ratio comparison with the Chi-square test (P < 0.05 indicates a statistically significant difference). Results: A total of 9 969 effective traps were placed at all the surveillance points, capturing 549 small mammals in total, of which 522 were rodents. The total density of small mammals was 5.51%. The total density of rodents was 5.24%. The rodent density was highest in Honghuagang District (12.94%), followed by Fenggang County (12.34%), and lowest in Chishui City (1.80%). There was a statistical difference in rodent density between the counties/districts (χ²=195.619, P < 0.001). Rattus norvegicus was the dominant rodent species in urban residential areas, rural residential areas, and key industries, while Apodemus agrarius was the dominant species in farming areas. The composition of rodent species statistically differed in different regions (the center, north, east, and west) of Zunyi (χ²=117.357, P < 0.001). Each small mammal was examined for Leptospira interrogans and Orientia tsutsugamushi in the liver, spleen, and kidney; Dabie bandavirus in the liver, spleen, and lung; and Hantavirus in the lung. Among 343 samples tested, 27 were positive, all for L. interrogans, with a pathogen detection rate of 7.87%. Shrews had the highest detection rate (16.00%), followed by A. agrarius (12.35%), and R. norvegicus had the lowest detection rate (1.64%). There was a significant difference in the detection rates of different species of small mammals (χ²=14.372, P=0.002). The detection rate was 9.66% (26/269) in farming areas, which was highest, and 2.94% (1/34) in key industries, with negative detection results in urban and rural residential areas. There were no differences in detection rates between different habitats (χ²=5.171, P=0.160). The detection rate was 27.03% in Meitan County, followed by 25.00% in Suiyang County, and zero in Renhuai City, Fenggang County, and Yuqing County, with a statistical difference between different counties/cities/districts (χ²=35.409, P=0.001). Conclusions: The density of rodents was relatively high in Zunyi. The detection of L. interrogans should be a warning of the possibility of related diseases. Local authorities should strengthen rodent control in spring and autumn and take comprehensive control measures according to actual situation and dominant rodent species and pathogen detection status in different habitats, so as to reduce the density of rodents and prevent the occurrence of rodent-borne diseases.

Objective To analyze the genetic diversity of nine batches of Lasiopodomys brandtii rodents from three sample plots (New Barag Right banner, East Ujimqin banner, and Xilinhot city) of the Inner Mongolia Autonomous Region (Inner Mongolia), China by using 16 pairs of microsatellite primers. Methods A total of 275 L. brandtii rodents were trapped using snaps or cages in May, July, and September of 2021. DNA was extracted from them with magnetic beads, followed by PCR amplification with 16 pairs of fluorescent-labeled microsatellite primers. The microsatellite data were obtained using GeneMarker. The genetic diversity and structure of L. brandtii populations were analyzed using GenAIEx 6.5, Arlequin (version 30), and structure 2.3.4. Results A total of 472 alleles were detected by using 16 pairs of microsatellite primers. The average polymorphic information content was 0.821 3. The average Shannon’s information index was 1.812. Observed heterozygosity ranged from 0.478 to 0.951. Expected heterozygosity ranged from 0.575 to 0.891. According to cluster analysis and principal component analysis, the nine L. brandtii populations could be divided into four groups by month. The genetic diversity index of the four groups was May > July > September. The analysis of molecular variance showed that the variation among individuals (88.51%) was much greater than that among the groups (5.04%) and that among the populations (6.45%). The mantel test showed no significant correlation between genetic distance and geographical distance of L. brandtii ( R ²=0.001 6). Conclusions The L. brandtii populations sampled in Inner Mongolia had high genetic diversity. The genetic variation of L. brandtii populations was mainly observed among individuals. Seasonal variation could be the main factor affecting the genetic structure of L. brandtii populations.

Objective To analyze the epidemiological characteristics (temporal, spatial, and demographic distributions) of indigenous and imported cases of dengue fever reported in Chinese mainland from 2005 to 2020. Methods The seasonal characteristics of dengue fever were analyzed using Excel 2010. Trend analysis was performed on the annual median age of disease onset using the Mann-Kendall test with the use of R 4.0.2. The map visualization and spatial analysis of cases were conducted using ArcGIS 10.3 software. Results A total of 81 648 indigenous cases of dengue fever were reported in 14 provinces (autonomous regions or municipalities) of Chinese mainland from 2005 to 2020. The indigenous cases were reported between May and December, concentrated between August and November (98.26%), and were distributed south from 35°36?N, mainly in Guangdong (74.01%) and Yunnan (13.74%) provinces, indicating seasonal and regional characteristics. Two major outbreaks of dengue fever occurred in 2014 and 2019, with 46 033 and 15 376 indigenous cases, respectively, adding up to 75.21% of the total indigenous cases. Among the local cases from 2005 to 2020, the male-to-female ratio was 0.99∶1; 54.93% were aged between 25 and <55 years; the top three frequent occupations were engagement in housework or unemployment (21.40%), service workers (12.46%), and retirees (11.71%). The median age of the total indigenous cases was 40 years (interquartile range [IQR]: 27-54). The difference of overall trend of the median age of indigenous cases since 2005 was not statistically significant ( Z=1.510, P=0.131). There were a total of 12 701 imported cases in 30 provinces (autonomous regions or municipalities) except the Tibet Autonomous Region in Chinese mainland from 2005 to 2020. The imported cases were reported throughout a year, frequently between June and November (81.81%), and were mainly distributed in Yunnan, Guangdong, Fujian, and Zhejiang provinces, suggesting seasonal and regional characteristics. The imported cases were mainly from Southeast Asian countries including Myanmar and Cambodia. In 2019, the number of imported cases reached a peak of 5 813, accounting for 45.77% of the total imported cases. Among the imported cases from 2005 to 2020, the male-to-female ratio was 2.05∶1; 73.29% were aged between 25 and 54 years; the top three frequent occupations were farmers (24.13%), service workers (19.34%), and engagement in housework or unemployment (13.91%). The median age of the total imported cases was 33 years (IQR: 26-44). The overall trend of the median age of imported cases since 2005 was not statistically different ( Z=0.413, P=0.679). A total of 15 376 indigenous cases and 5 813 imported cases reported in 2019, and the number of indigenous and imported cases reported were dramatically decreased to 616 and 158 in 2020, respectively. Conclusions Dengue fever outbreaks in Chinese mainland are still caused by imported cases, with significant seasonal and regional characteristics. The indigenous cases were mainly distributed in Guangdong and Yunnan provinces, while the imported cases were mainly from Southeast Asian countries including Myanmar and Cambodia. There was no significant change in the median age of dengue fever cases from 2005 to 2021.

Objective To determine the species and positive rate of Rickettsia carried by gamasid mites on the body surface of rodents in Inner Mongolia Autonomous Region (Inner Mongolia), China, and to provide a basis for the prevention and control of local infectious diseases. Methods DNAs of gamasid mites on the body surface of rodents in different areas of Inner Mongolia were extracted, and the 17 kDa gene sequence was amplified by nested polymerase chain reaction (PCR). The outer membrane protein A ( ompA) sequence was amplified for samples positive for the 17 kDa gene. The PCR products obtained by amplification were sequenced, and the phylogenetic tree was constructed after homology comparison between the sequencing results and the sequences from the National Center for Biotechnology Information, USA. Results Rickettsia was detected in 11 of 536 gamasid mites, and the total positive rate was 2.05%. The species of Rickettsia included R. heilongjiangensis, a sibling species of R. felis, and an unknown species of Rickettsia. Their host mites included Haemogamasus mandschuricus, Eulaelaps cricetuli, Hg. kitanoi, Haemolaelaps glasgowi, and deutonymphs of Parasitus sp ., with the positive rates of 8.89%, 3.39%, 2.22%, 0.68%, and 12.50%, respectively. The hosts that carried gamasid mites positive for Rickettsia included Spermophilus dauricus, Allactaga sibirica, and Lasiopodomys brandtii. Conclusion Gamasid mites on the body surface of rodents in Inner Mongolia carry a variety of Rickettsia, including the species that are human pathogen.

Objective To assess the risk of Anopheles barbirostris invading China under future climate change scenarios, and to provide a basis for monitoring and early warning. Methods The maximum entropy model was used to predict the recent global potential distribution and project the future potential distribution of An. barbirostris in China. The main environmental factors affecting the distribution of An. barbirostris were analyzed based on the contribution rate of environmental factors. The vector risk assessment index system was established to calculate the comprehensive risk value of invasive species. Results A total of 99 effective distribution points of An. barbirostris were identified. The rainfall in September played a leading role in affecting the distribution of potential suitable areas of An. barbirostris. The omission rate of model training was roughly the same as the theoretical omission rate, and the area under the receiver operating characteristic curve was 0.988. Under the current climate scenario, the potential suitable areas of An. barbirostris in China were mainly in Guangdong province, Guangxi Zhuang Autonomous Region, and Hainan province as well as the eastern Sichuan Basin. In 2081-2100, China has the largest potential suitable area (207.51×10 ⁴ km ²) under the shared socioeconomic pathway 585 climate scenario, and the area of suitable area will show an increasing trend under various climate scenarios. Through the risk assessment index system, it was calculated that the comprehensive risk value of An. barbirostris was 0.57, so An. barbirostris belonged to the medium-risk invasive species. Conclusions An. barbirostris is a species with a medium invasion risk. In the future, the mosquito vector surveillance system should be improved according to the distribution of its suitable areas, and scientific prevention and control strategies should be formulated.

Objective To investigate the microbiota of the dominant tick species Rhipicephalus microplus in the minority autonomous prefectures of Guizhou province, China, and to provide a scientific basis for the prevention and control of tick-borne disease. Methods Rh. microplus ticks were collected from the body surface of cattle and sheep at 18 sampling sites located in Qiandongnan Miao and Dong Autonomous Prefecture, Qiannan Buyi and Miao Autonomous Prefecture, and Qianxinan Buyi and Miao Autonomous Prefecture in April and July of 2019 and 2020. The ticks were grouped by region, growth stage, and sex, with three parallel samples in each group, followed by metagenomic sequencing. The sequencing results were processed with quality control and assembly procedures before homology alignment with the non-redundant protein database of National Center for Biotechnology Information to obtain taxonomic annotation information. R (v. 3.6.3) and GraPhlAn (v. 1.1.3) were used for visual analysis, including species composition analysis, non-metric multidimensional scaling (NMDS) analysis, and analysis of similarities (ANOSIM). Results The dominant bacterial phylum for Rh. microplus was Firmicutes (60.70%), followed by Proteobacteria (33.76%) and Actinobacteria (4.53%). Staphylococcus aureus (38.29%) was the dominant bacterial species, followed by Klebsiella pneumoniae (7.79%) and Streptococcus pneumoniae (5.26%). Several tick-borne pathogens were detected, including various genotypes of spotted fever group Rickettsia and Anaplasma phagocytophilum (1.38%). R. fournieri (2.91%) was an emerging rickettsiae detected from ticks for the first time in China, and R. japonica (1.76%) and R. monacensis (0.04%) were common tick-borne Rickettsia genotypes in China. R. fournieri and R. japonica were mainly carried by male ticks. The NMDS analysis showed that the microbiota composition of Rh. microplus differed by growth stage and sex. The ANOSIM analysis indicated reasonable grouping, with greater intergroup differences than intragroup differences ( R=0.147, P=0.014). Conclusions In the minority autonomous prefectures of Guizhou province, Rh. microplus ticks have a diverse microbiota composition, carrying pathogens that may cause spotted fever and human granulocytic anaplasmosis. Therefore, vector surveillance and pathogen detection should be strengthened, and effective control measures should be taken to reduce the risk of tick-borne diseases.