Spatio-temporal disparities of Clonorchis sinensis infection in animal hosts in China:a systematic review and meta-analysis

Background Clonorchis sinensis,one of the most important food-borne zoonotic trematodes,remains prevalent in China.Understanding its infection status in animals is crucial for controlling human clonorchiasis.Here we conducted a systematic review and meta-analysis to focus on the spatio-temporal disparities ofC.sinensis infection in animals in China.Methods Data onC.sinensis prevalence in snails,the second intermediate hosts,or animal reservoirs in China were extracted from electronic databases including PubMed,Embase,Web of Science,Chinese Wanfang database,CNKI,VIP,and China Biomedical Literature database.A random-effects meta-analysis model was utilized to estimate the pooled prevalence in each of the above animal hosts.Subgroup analysis and multivariable meta-regression were performed to explore potential sources of heterogeneity across studies and compare the temporal disparity of infection rates between high and low epidemic areas.Scatter plots were used to depict the biogeographical characteristics of regions reportingC.sinensis infection in animals.Results The overall pooled prevalence ofC.sinensis was 0.9%(95%CI:0.6-1.2%)in snails,14.2%(12.7-15.7%)in the second intermediate host,and 14.3%(11.4-17.6%)in animal reservoirs.Prevalence in low epidemic areas(with human prevalence<1%)decreased from 0.6%(0.2-1.2%)before 1990 to 0.0%(0.0-3.6%)after 2010 in snails(P=0.0499),from 20.3%(15.6-25.3%)to 8.8%(5.6-12.6%)in the second intermediate hosts(P=0.0002),and from 18.3%(12.7-24.7%)to 4.7%(1.0-10.4%)in animal reservoirs.However,no similar decrease in prevalence was observed in high epidemic areas(with human prevalence≥1.0%).C.sinensis infections were predominantly reported in areas with altitudes below 2346 m and annual cumulative precipitation above 345 mm and were mostly concentrated in eastern China.Conclusions There are spatio-temporal disparities in the animal infections ofC.sinensis in different areas of China.Animal infections are primarily concentrated in regions with low altitude and high precipitation.The results suggest that implementing One Health-based comprehensive measures targeting both humans and animals,especially in high epidemic areas,is essential for successful eradication ofC.sinensis in China.

Diversity and Distribution of Host Animal Species of Hantavirus and Risk to Human Health in Jiuhua Mountain Area,China

Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.

多房棘球绦虫在我国自然动物宿主的发现及其形态学研究

本文报告在我国宁夏固原地区野生动物首次发现多房棘球蚴痫的病原自然感染。当地红狐自然感染多房棘球绦虫成虫27.27％,感染强度1,840—4,050条;达乌尔黄鼠citellus dauricus自然感染多房棘球蚴0.2％。成虫孕节人工感染小白鼠后163—424天,在其肝脏内可检到发育含有大量成熟原头节的多房棘球蚴。成虫期与幼虫期的形态特征有详细的描述并同国外代表性地区的报告列表比较。对我国西北地区人体多房棘球蚴病作综合报道。

Transmission of Opisthorchis viverrini,Schistosoma mekongi and soil-transmitted helminthes on the Mekong Islands,Southern Lao PDR

Background:Prevalence of Opisthorchis viverrini,Schistosoma mekongi and soil-transmitted helminths(STH)remains high in Lao People’s Democratic Republic(Lao PDR),despite control efforts including mass-drug administration,education and communication campaigns.New approaches are required to advance helminth control.Methods:An ecohealth study was conducted on two Mekong islands in Southern Laos.Demographic and behavioural data were collected by questionnaire.Human and animal reservoir stools were examined.Bithynia spp.and Neotricula aperta snails were examined using shedding.Fresh water fish were examined using digestion technique.Multivariate random-effects analysis was used to find risk factors associated with helminth infections.Results:Human infection rates with O.viverrini,hookworm,S.mekongi,Trichuris trichiura,Ascaris lumbricoides and Taenia spp.were 60.7%,44.1%,22.2%,4.1%,0.6%and 0.1%,respectively.Heavy intensity infections were 4.2%,3.6%and 1.8%for O.viverrini,S.mekongi and hookworm,respectively.O.viverrini and S.mekongi infection rates among dogs and cats were 25.0%and 14.7%,respectively.Of the cats tested,53.1%were infected with O.viverrini.Prevalence of O.viverrini and S.mekongi in snails was 0.3%and 0.01%,respectively.Overall prevalence of O.viverrini infection in fresh water fish was 26.9%,with the highest infection rates occurring in Hampala dispa(87.1%),Cyclocheilichthys apogon(85.7%)and Puntius brevis(40.0%).Illiteracy and lower socioeconomic status increased the risk of O.viverrini infection,while those aged 10-16 years and possessing latrines at home were less likely to be infected.Household dogs and cats that consumed raw fish were significantly and positively associated with O.viverrini infection of the household members.For S.mekongi,children under 9 years old were exposed significantly to this infection,compared to older age groups.Conclusions:There is a pressing need to design and implement an integrated helminth control intervention on the Mekong Islands in southern Lao PDR.Given the highly dynamic transmission of O.viverrini,S.mekongi,STH and extended multiparasitism,annual mass-drug administration is warranted along with environmental modifications,health education and improved access to clean water and adequate sanitation to consolidate morbidity control and move towards elimination.Trail registration number:Our findings presented here are from a cross-sectional study,therefore,it has not been registered.