河南省商丘地区猪旋毛虫感染调查

目的了解河南省商丘地区猪的旋毛虫自然感染情况。方法在河南商丘某县农村的3个生猪屠宰点,收集屠宰猪的膈肌样本,分别应用压片镜检法和人工消化法对肌肉样本进行旋毛虫检验。结果 273头屠宰猪均为圈养猪,肌肉样本应用镜检法与消化法的幼虫检出率分别为0（0/273）与3.30%（9/273）（χ2=7.230,P〈0.05）,阳性肉样的平均每g肌肉虫荷（larvae per gram,lpg）为0.48。结论河南省商丘地区农村圈养猪的旋毛虫感染率较高,但感染度较低;在旋毛虫病低度流行区应使用消化法对猪肉进行旋毛虫检验。     

许昌市旋毛虫病流行病学调查

１９９６ ～１９９７ 年,分别在河南省许昌市的许昌县及鄢陵县进行人群及动物旋毛虫病流行病学调查。结果发现家猪旋毛虫感染率为２ ．６１％ 。血清学检查,家猪、家鼠及人旋毛虫抗体阳性率依次为５ ．４５ ％ ,６ ．６１％ 和４ ．８５ ％ ;汉民血清的阳性率（８ ．８２ ％ ） 高于回民（０ ．９６％ ）。对同１ 份家猪肌肉标本采取直接压片法、人工消化法及血清学抗体检测３ 种方法检查,发现直接压片法容易漏检,人工消化法及血清学抗体检测法的检出率较高。提示目前当地取上市猪肉膈肌直接压片镜检旋毛虫检疫方法亟待改进。为不漏检,建议对猪肉上市前检疫时先用血清学试验初筛,对检出阳性者再用人工消化法确证。     

应用单克隆抗体胶乳结合物凝集试验快速检查猪肉旋毛虫幼虫

检查猪肉旋毛虫幼虫,以膈肌小样本(<1g)直接镜检,虽然简单有效,但不能检出每克组织少于3条幼虫的样本。每人每天至多只能查60头猪。而传统消化法需时17h,其后仍需仔细作镜检。本文作者用消化一胶乳凝集法取代旋毛虫镜检法,并比较了两法检测102份猪肉标本的效果。每份猪膈肌标本制成0.05g的样本5份,在玻片上加压后用解剖显微镜检查旋毛虫幼虫。另取样本2g,用胃蛋白酶消化2h,释出幼虫,然后镜检旋毛虫幼虫。不论结果如何,均将全部沉淀物移入微量离心管,离心沉淀物经超声粉碎,其上清液用于胶乳凝集试验。     

旋毛虫对昆明小鼠最小感染剂量的实验研究

为观察旋毛虫感染昆明小鼠的最小剂量, 将70只雄性昆明小鼠随机均分7组, 每只鼠分别经口感染旋毛虫肌幼虫30、 25、 20、 15、 10、 5及3条, 感染后6周剖杀。取完整膈肌, 压片、 镜检、 计数虫荷。小鼠全身肌肉经人工胃液消化后计数肌肉虫荷。结果, 压片镜检法和人工消化法的幼虫检出率, 感染30、 25、 20、 15及10条旋毛虫肌幼虫的小鼠均为100% (10/10); 感染5条旋毛虫肌幼虫的小鼠, 两种方法幼虫检出率分别为70% (7/10) 和100% (10/10); 感染3条旋毛虫肌幼虫的小鼠, 两种方法均未检出幼虫。感染旋毛虫的小鼠膈肌和肌肉虫荷与感染剂量均呈正相关(r=0.759, P＜0.05; r=0.638, P＜0.05)。旋毛虫经口成功感染昆明小鼠的最小剂量为5条幼虫。     

许昌市旋毛虫流行病学调查

１９９６￣１９９７年,分别在河南省许昌市的许昌县及鄢陵县进行人群及动物旋毛虫病流行病学调查。结果发现家猪旋毛虫感染率为２．６１％。血清学检查,家猪、家鼠及人旋毛虫抗体阳性率依次为５．４５％,６．６１％和４．８５％;汉民血清的阳性率（８．８２％）高于回民（０．９８％）。对同１份家猪肌肉标本采取直接压片法,人工消化法及血甭学抗体检测３种方法检查,发现直接压片法容易漏检,人工消化法及血清学抗体检测法的检     

免疫层析试纸条检测实验感染猪肉汁抗旋毛虫抗体的研究

目的观察免疫层析试纸条对实验感染猪肉汁中抗旋毛虫抗体的检测效果。方法以胶体金标SPA和旋毛虫肌幼虫ES抗原制备了免疫层析试纸条。将30头家猪随机分为2组：实验感染组20头,每头经口感染5000条旋毛虫幼虫,正常对照组10头。感染后10w用试纸条进行血清及肉汁抗体检测,并与镜检法进行比较。结果应用试纸条检测旋毛虫幼虫感染的家猪血清及肉汁的抗体阳性率均为100%（20/20）,肌肉压片镜检法的幼虫检出率亦为100%（20/20）,每克腿肌虫荷为111～400条幼虫（平均为231.36条）。应用试纸条和镜检法对正常对照组肉汁及膈肌时均为阴性。感染猪肌肉-20℃保存8个月的肉汁抗体阳性率亦为100%（20/20）。结论试纸条检测肉汁中旋毛虫抗体可用于新鲜肉及冷冻猪肉中旋毛虫检疫的初筛。     

镜检法与贝氏法对肉类中旋毛虫成囊前幼虫的检验效果

目的观察镜检法（trichinelloscopy）与贝氏法（Baermann’s technique）对肉类中旋毛虫成囊前幼虫（pre-encap-sulated larvae,PEL）检验的效果。方法将80只昆明小鼠随机分为8组（每组10只）,每只感染旋毛虫肌幼虫300条,感染后14～21d每天剖杀1组,应用贝氏法检查小鼠肌肉中的PEL（9～16日龄）,用镜检法检查膈肌中的PEL,用ELISA检测鼠血清抗旋毛虫抗体。另取12只小鼠,用于观察消化法对旋毛虫感染后17～19d（12～14日龄）PEL存活率的影响。结果小鼠感染旋毛虫后14和15d镜检法幼虫检出率分别为50.0%和89.0%,感染后16～21d检出率均为100%。感染后14～21d贝氏法的检出率均为100%;ELISA检测血清抗体阳性率为11.1%～40.0%。感染后14d贝氏法的PEL检出率与镜检法比较差异有统计学意义（χ^2=5.333,P〈0.05）;观察期间ELISA检测的抗体阳性率均显著低于镜检法和贝氏法的幼虫检出率（χ^2=18.9,P〈0.05）。感染后17～19d,小鼠肌肉消化4h的幼虫存活率均明显低于消化1h的存活率（χ^217=117.56,χ^218=37.48,χ^219=96.73,P均〈0.05）。结论旋毛虫感染后17～19d的成囊前幼虫不能完全抵抗胃蛋白酶的消化作用;对肉类中旋毛虫成囊前幼虫的检疫效果,贝氏法优于镜检法。     

免疫层析试纸条检测轻度感染小鼠肉汁抗旋毛虫抗体的研究

目的观察免疫层析试纸条对轻度感染小鼠肉汁中抗旋毛虫抗体的检测效果。方法以胶体金标SPA和旋毛虫肌幼虫ES抗原制备免疫层析试纸条。将70只雄性昆明小鼠随机分为7组(每组10只),每组分别经口感染30、25、20、15、10、5、3条旋毛虫幼虫,感染后6周用试纸条进行血清及肉汁抗体检测,并与ELISA、镜检法及消化法的检测结果进行比较。结果30、25、20、15、10条旋毛虫幼虫感染的小鼠,试纸条与ELISA的血清及肉汁抗体阳性率均为100(10/10),镜检法与消化法的幼虫检出率均为100%(10/10)。5条旋毛虫感染的10只小鼠,镜检法和消化法的幼虫检出率分别为70%(7/10)和100%(10/10),消化法检查时10只小鼠的每克肌肉虫荷为0.88~3.14条幼虫(平均为1.58条),试纸条与ELISA检测时的血清及肉汁抗体阳性率均为100%(10/10)。3条旋毛虫感染的10只小鼠,4种方法检测时均为阴性。结果表明,试纸条检验肉类中旋毛虫的敏感性与ELISA和消化法相同,且明显高于镜检法(P<0.05)。低剂量旋毛虫感染小鼠后6周的肉汁抗体水平与感染剂量呈正相关(P<0.05),肉汁与血清抗体水平均具有相关性(P<0.05)。结论每克小鼠肌肉仅含0.88条旋毛虫幼虫时也可被试纸条检出,试纸条可用于轻度感染肉类中旋毛虫检疫的初筛。     

免疫层析试纸条检测感染小鼠肉汁中抗旋毛虫抗体的研究

目的 建立一种肉类旋毛虫感染的快速免疫学检测方法.方法 以胶体金标SPA和旋毛虫肌幼虫ES抗原制备免疫层析试纸条,对不同剂量旋毛虫幼虫感染小鼠后不同时间的血清及肉汁抗体进行检测,并与ELISA、镜检法及消化法的检测结果进行比较.结果 用100、300、500条旋毛虫幼虫感染小鼠后6周,3组小鼠的血清及肉汁抗体阳性率均达100%;试纸条法对血清与肉汁的抗体检出率差异无统计学意义(χ2=0.22, P＞0.05).试纸条法和ELISA检测100条幼虫感染小鼠肉汁的阳性率分别为91.3%和100%(χ2=2.09, P＞0.05),检测300、500条幼虫感染小鼠肉汁的阳性率均为100%;试纸条法和镜检法对3组小鼠感染后5～7周的肉汁和膈肌检测的阳性率均为98.6%.消化法检查每克肌肉虫荷＜33条幼虫的6份标本,试纸条5份阳性,每克肌肉中含有6条幼虫时可被试纸条法检出.感染旋毛虫小鼠肌肉4 ℃保存1～7 d及-20 ℃保存1～7个月的肉汁抗体阳性率均为100%.结论 免疫层析试纸条可用于新鲜肉、冷藏肉及冷冻肉中抗旋毛虫抗体的检测.     

旋毛虫成囊前期幼虫的收集

目的 探索旋毛虫成囊前期幼虫的收集时间与方法.方法 20只成年大鼠,每只大鼠经口感染3000条旋毛虫脱囊幼虫,分别于第14、15、16、17、18、19、20天将大鼠处死,用人工胃蛋白酶消化肌肉收集旋毛虫.结果 感染后第14、15、16大膈肌均未见旋毛虫,第17、18、19、20天膈肌有旋毛虫的侵入并逐渐增多;第14、15、16天均未收集到旋毛虫,第17、18、19、20天平均每只大鼠分别收集5000、8000、10000、30000条旋毛虫.结论 旋毛虫在感染后第20天是旋毛虫成囊前期幼虫收集的最佳时期.人工胃蛋白酶消化肌肉可以收集成囊前期幼虫.     

Evaluation of the meat carcases assigned for consumption towards the presence of Trichinella larvae by two methods: trichinoscopy and digestion

The main purpose of this article was to analyse the effectiveness of two methods: trichinoscopy and digestion method for control of animal trichinellosis. It was established that the using of magnetic stirrer improved the digestion of meat and shortened the digestion to 90-100 minutes. It is worthy of notice that the digestion method is three to four times more sensitive than the traditional trichinoscopy. In the years 1999-2004 Trichinella larvae were found in pork meat 6 times rarely comparing with the years 1990-1994. The introduction of digestion method resulted directly in the reduction (4 times) of the Trichinella infection in humans in the years 2000-2004 comparing with the years 1990-1994. The ELISA test appeared to be also very useful for epidemiological studies on Trichinella infection in animals and humans.     

人工消化法对肉类中旋毛虫检疫敏感性的研究

目的观察人工消化法对肉类中旋毛虫检疫的敏感性。方法将100g猪肉搅碎后等分为50份（每份2g）,每克猪肉分别加入1、2、3、4及5个旋毛虫幼虫囊包,搅拌均匀后按国际旋毛虫病委员会推荐的人工消化法在43℃消化4h～5h,用60目（300μm孔径）铜筛过滤,室温沉淀30 min后检查幼虫。结果每克猪肉含1、2条旋毛虫幼虫时消化法的幼虫检出率分别为10%（1/10）和30%（3/10）;每克猪肉含3条及3条以上幼虫时,消化法的幼虫检出率为100%（10/10）。结论人工消化法对轻度旋毛虫感染（每克肌肉含1～2条幼虫）的2g肉样标本检疫时的敏感性较低。     

Wild and domestic animals as permanent Trichinella reservoir in Poland

BACKGROUND: [corrected] Since Owen first described Trichinella as a human patogen in 1835, the number of organisms comprising this genus has grown dramatically. This etiological agent of human trichinellosis shows worldwide distribution in domestic and/or sylvatic animals. MATERIAL AND METHOD: The aim of the presented paper was to determine the distribution of Trichinella species in wild animals such as red foxes, wolves, wild boars, and domestic pigs in Poland. Muscle samples from diaphragm and forelegs were collected from animals killed by hunters. Muscle larvae were recovered from the muscle after artificial digestion and identified at the species level by RAPD, PCR-RPLF and multiplex PCR. RESULTS: Of 75 nematode isolates from red foxes: (Vulpes vulpes), 50 resulted as T. britovi, 6 T. spiralis, 6 were mixed infections of these two species. Fifteen Trichinella isolates remained unidentified. Of 97 nematode isolates from wild boars (Sus scrofa), 21 resulted as T. britovi, 69 T. spiralis, 2 were mixed infections of these two species. Five Trichinella isolates remained unidentified. Of 6 examined wolves (Canis lupus) killed in the Bieszczady region, 3 animals were positive against T. britovi. Of 6 examined raccon dogs (Nyctereutes procyonoides) from Pomorskie region, 2 animals were positive against T. spiralis. Of 21 nematode isolates from domestic pigs, 1 resulted as T. britovi and 21 as T. spiralis. Up to date, two Trichinella species are detected as the etiological agents of epidemiology among domestic and wildlife animal in Poland: T. britovi is the dominant species in red foxes and T. spiralis is the dominant species in wild boars and domestic pigs.     

免疫层析试纸条检测感染小鼠肉汁中抗旋毛虫抗体的研究

目的建立一种肉类旋毛虫感染的快速免疫学检测方法。方法以胶体金标SPA和旋毛虫肌幼虫ES抗原制备免疫层析试纸条,对不同剂量旋毛虫幼虫感染小鼠后不同时间的血清及肉汁抗体进行检测,并与ELISA、镜检法及消化法的检测结果进行比较。结果用100、300、500条旋毛虫幼虫感染小鼠后6周,3组小鼠的血清及肉汁抗体阳性率均达100%;试纸条法对血清与肉汁的抗体检出率差异无统计学意义（χ2=0.22,P〉0.05）。试纸条法和ELISA检测100条幼虫感染小鼠肉汁的阳性率分别为91.3%和100%（χ2=2.09,P〉0.05）,检测300、500条幼虫感染小鼠肉汁的阳性率均为100%;试纸条法和镜检法对3组小鼠感染后5-7周的肉汁和膈肌检测的阳性率均为98.6%。消化法检查每克肌肉虫荷〈33条幼虫的6份标本,试纸条5份阳性,每克肌肉中含有6条幼虫时可被试纸条法检出。感染旋毛虫小鼠肌肉4℃保存1-7 d及-20℃保存1-7个月的肉汁抗体阳性率均为100%。结论免疫层析试纸条可用于新鲜肉、冷藏肉及冷冻肉中抗旋毛虫抗体的检测。     

人工消化法检验旋毛虫效果及其对肌幼虫的影响

目的观察人工消化法检验旋毛虫的效果及对肌幼虫活性、感染性的影响。方法将小鼠感染100条肌幼虫后30 d剖杀,分别应用3组消化法检验,即：消化2 h组（磁力搅拌法）、消化12 h组、消化20 h组,每组取肉样10份,每份含300个囊包,消化后分别计数每份肉样的幼虫数;同时对幼虫活性进行观察。40只昆明小鼠随机分为对照组和3个消化组（消化2、12、20 h组）,共4组,每组10只。对照组：每鼠感染100个囊包;消化组：将3组方法收集的幼虫分别感染小鼠,每鼠经口感染100条幼虫。感染后30 d剖杀,取膈肌压片镜检,并用磁力搅拌法收集幼虫、计数。结果消化2、12、20 h组的幼虫检出率分别为78.47%、76.73%、68.63%,死亡率分别为0.59%、4.60%、7.43%。3组收集的幼虫分别感染小鼠,30 d后剖杀,与对照组相比,消化2、12、20 h组的减虫率分别为60.56%、61.94%、73.07%。结论磁力搅拌法（消化2 h）在幼虫检出率、幼虫活性、幼虫感染性等方面均优于消化12、20 h实验组,为进行旋毛虫检验和动物实验,优先选择的方法。     

The usefulness of ELISA test for early serological detection of Trichinella spp. infection in pigs

Trichinellosis is a parasitic zoonosis transmitted to humans through consumption of raw or undercooked meat from animals infected with nematodes of the Trichinella genus. Every year seropositive cases are found among the human population and thus trichinellosis still remains an epidemiologically important disease. The first step of the study was the optimization of a new ELISA method enabling an early and specific serological diagnosis of trichinellosis in pigs and wild boars using excretory-secretory (ES) antigens obtained from in vitro cultures of L1 T. spiralis. Serum samples were assayed for anti-T. spiralis IgG antibodies using the new ELISA protocol and a reference test--Standard manufactured by Institut Pourquier. The optimization involved the selection of suitable plates for antigen coating, dilution of sera and antibodies and their time of incubation. On the basis of the optimization a new ELISA procedure for the detection of IgG and IgM against T. spiralis was elaborated. Conventional, Iberian pigs and SPF (Specific Pathogen Free) pigs were infected with 200, 1000 and 20,000 muscle larvae of T. spiralis. Serum samples were obtained at 5 and 1 dbi (day before infection), and 5, 10, 15, 20, 25, 30, 40, 50, 60 dpi (day post infection) and screened for specific IgG antibodies against excretory-secretory L1 T. spiralis antigens. Serum samples were obtained from the EU project Trichiporse: "Safe pork and horse meat on EU markets: early and unbiased diagnostic tests for Trichinella". Field samples of conventional pigs (1474) and wild boars (1784) were obtained from slaughter houses in different parts of Poland. Pigs were examined for the presence of Trichinella spp. using the artificial digestion method. Only four pigs were naturally infected with T. spiralis, the remaining were Trichinella larvae free. ELISA was used to examine IgG levels against L1 T. spiralis in pig and wild boar sera. The usefulness of ELISA for anti-IgG detection in pigs is usually limited by the nature of the antigen. The antigens were prepared in different laboratories: in Germany--Ag ES L1 T. spiralis (N), Italy--Ag ES L1 T. spiralis (W)) and in Poland--Ag ES L1 T. spiralis. Cut-off values for ELISA along with the estimated sensitivity and specificity were calculated using different methods: S/P%, M+3SD and ROC (Receiver Operating Characteristic). In SPF and Iberian pigs inoculated with 200, 1000 and 20,000 L1 T. spiralis, specific antibodies were detected 40, 30 and 25 dpi, respectively, with the use of the Standard (reference test). The analysis of the two ELISA procedures demonstrated a high sensitivity and specificity for the newly elaborated test utilizing the Ag ES L1 T. spiralis. In conventional pigs infected with 20,000 L1 T. spiralis specific antibodies were detected from 20 dpi when employing the new protocol. Similar results for the Standard and new ELISA test were obtained for serum samples of conventional pigs infected with 200 and 1000 larvae, which became positive from 40 dpi and 30 dpi, respectively. The results showed that both: the Standard and new protocols were comparable, and based on this, the new test was applied for further research. Results obtained adopting the new protocol with three antigens showed that two of them: Ag ES L1 T. spiralis (W) and Ag ES L1 T. spiralis are similar. The specific IgG antibodies for infective doses of 200 and 1000 larvae for these antigens were detectable 40 and 30 dpi respectively. In pigs infected with the highest dose of T. spiralis larvae IgG antibodies were detectable from 20 dpi when Ag ES L1 T. spiralis was used. These results strongly indicate that in examined pigs, the specific IgG response to T. spiralis infection is dose dependant. Of 1474 examined pig sera only 0.99% gave a positive signal against ES L1 T. spiralis antigen. Of 1784 examined wild boars sera only 0.68 % gave positive results using the new ELISA protocol. ELISA is a useful method for detecting specific IgG antibodies in pigs experimentally infected with different doses of T. spiralis and naturally infected pigs. In pigs the specific IgG response is dose dependant. The Ag ES L1 T. spiralis increases the specifity of the method and reduces false positive results. Simultaneous use of both methods: digestion and ELISA for the diagnosis of Trichinella in naturally infected pigs and wild boars may increase the chances of eliminating meat infected with T. spiralis larvae.     

Trichinellosis in swine and wild boars in Poland from 1993 to 1998

The prevalence of Trichinella sp. among 97, 193, 480 swine and 309,040 wild boars was determined by artificial digestion method. Pork meat was about 6 times less infected with Trichinella sp. in the years 1997-1998 than in the years 1993-1994. In the years 1993-1994 894 positive Trichinella sp. cases (prevalence--0.0029%) in pork meat were established. The prevalence of Trichinella larvae infection in pork meat in the years 1997-1998 was 0.00030%--larvae were found in 141 cases, only.