| The intestinal protozoal diseases have been concerned for food-borne transmission as a result of globalization of food supply,diversification of dietary habit and internationalization of travel industry.Protozoa are a diverse group of organisms.There are over 30 phyla,but the enteric ones causing food-borne human disease belong to the phyla Apicomplexa,Rhizopoda,Zoomastigina,Microspora and Ciliophora,among which may cause economic consequences and serious illnesses.Cryptosporidium,Cyclospera,Giardia and Microsporidium are more common intestinal parasitic protozoa,which mainly transmit by food and water routes,causing self-limiting diarrhea in immune-competent humans and persisting,deadly diarrhea in immune-compromised individuals,especially associated with HIV.Microsporidia are a group of obligate intracleeular and single-celled eukaryotic parasites,which infect almost all of the animals from invertebrates to humans.Since its identification in AIDS patient in 1985,cases of intestinal microsporidiosis have been increasingly reported in mammal.Thus far,at least 8 genus,14 species of microsporidia are known to infect humans,among that Enterocytozoon bieneusi is the most common zoonotic species.It has shown to be a major cause of acute,self-limiting or inapparent infection in immune-competent indiciduals,and chronic,persistent diarrhea are the most common symptoms infected with Enterocytozoon bieneusi in immune-deficient humans,while severe cases may causing life-threatening.In order to realize the bring situation of Enteric protozoa on the surface of fruits and vegetables in parts of Henan province,363 samples of fruits and vegetables were collected from farmers market and private gardening in Zhengzhou and Kaifeng from June to October in 2014.Refer to the method established by Steele,Joan and Sun Fangfang dealt with samples including elution,concentration and amplification.The nested PCR amplification of E.bieneusi based on ITS gene and of Cryptosporidium,Cyclospera and Giardia based on SSUr RNA,Cryptosporidium was found in 1 sample,Enterocytozoon was found in 26 samples,and its bring situation was 0.3% and7.2%,respectively.No Cyclospera and Giardia were found.Investigation of four kinds of fruits and vegetables including leafy-young and flowers liverwors,roots,solanaceouses and cucurbits all carried parasites,the infection rates were 6.3%(17/268),7.1%(3/42),17.4%(4/23)and 10.0%(3/30),respectively.There found two parasitic protozoon of Cryptosporidium and Enterocytozoon on the surface of watermelon.To investigate the prevalence of Enterocytozoon bieneusi in dairy cattle and evaluate its potential zoonosis in parts of Henan province,a total of 764 fecal DNA samples were amplified by nested PCR,the result shows that there were 153 positive samples,and the overall infection rate was 20.0%.Different infection rates in dairy cattle of Zhengzhou and Zhongmou were 16.3%(42/257)and 21.9%(111/507),respectively.and there is no statistically significant difference between them(?2=3.28,P?0.07).The difference in infection rates among calf(21.2%),breeding cattle(24.1%),youth and adult cattle(0,12.3%)was statistically significant(P?0.01).There was a lowest infection rate 9.4% in winter,other seasons were 22.3%(spring),27.2%(summer),and 27.6%(autumn),respectively(?2=31.67,P?0.0000000001).Twelve known genotypes(CM8?H?Ebp A?Ebp C?I?J?BEB4?BEB6?BEB8?COS-??CD6 and D)and four new genotypes(named as ZZ1?ZZ2?ZM1 and ZM2)were observed in 153 positive samples through sequence analysis and comparison.Among that genotype J had the highest infection rate 34.6%.Genotype Ebp C,I,J and BEB6 were both found in two dairy cattle farms.The highest and lowest genotypes were BEB6(23.8%)and CD4(2.4%)in Zhengzhou dairy cattle farm.and in Zhoumou genotype J was the highest(40.5%),then was genotype I(33.3%).To identify the infection status of Enterocytozoon bieneusi in a diary farm in Ningxia,a total of 109 diarrhea calves stool specimen were collected and amplified by PCR,finding 51 positive samples,the infection rate was 46.8%,of which 1month years old,two month and three month years old were 41.5%?68.8%and46.4%,respectively,and there was no statistically significant.A total of 8 E.Bieneusi ITS genotypes were observed through sequence analysis and comparison.They consisted of five konwn genotypes including I?J?CM8?Ebp A and O,and three new ones named as NX1?NX2 and NX3.Genotype J,the dominant genotype,which had the highest infection rate was 46.8%.This study investigate the bring situation of protozoa on the surface of fruits and vegetables in Zhengzhou and Kaifeng of Henan province,and also investigate the prevalence of Enterocytozoon bieneusi in Henan and Ningxia three diary cattle farms.Sequence analysis and phylogenetic analysis revealed that cattle may be the reservoir host of infected human Enterocytozoon bieneusi,which existed public health significance and zoonotic risk,provided of reference basis in preventing and controlling human microsporidiosis. |
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