Toxoplasma gondii infection in the United States, 1999-2000

Infection with Toxoplasma gondii can lead to congenital and acquired disease, resulting in loss of vision and neurologic illness. We tested sera collected in the National Health and Examination Survey (NHANES) from 1999-2000 for T. gondii-specific immunoglobulin G antibodies and compared these results with results from sera obtained in the NHANES III survey (1988-1994). NHANES collects data on a nationally representative sample of the U.S. civilian population. Of 4,234 persons 12-49 years of age in NHANES 1999-2000, 15.8= (age-adjusted, 95% confidence limits [CL] 13.5, 18.1) were antibody positive; among women (n = 2,221) 14.9= (age-adjusted, 95% CL 12.5, 17.4) were antibody positive. T. gondii antibody prevalence was higher among non-Hispanic black persons than among non-Hispanic white persons (age-adjusted prevalence 19.2% vs. 12.1%, p = 0.003) and increased with age. No statistically significant differences were found between T. gondii antibody prevalence in NHANES 1999-2000, and NHANES III. T. gondii antibody prevalence has remained stable over the past 10 years in the United States.     

宁波市婚前妇女弓形虫感染的流行病学研究

目的　探讨婚前妇女弓形虫感染水平及其治疗方案。方法　采用ＥＬＩＳＡ法对宁波市１２ ２２４名婚前妇女进行了弓形虫感染检测（包括弓形虫循环抗原ＣＡｇ、特异性ＩｇＧ和ＩｇＭ 抗体）。结果　婚前妇女弓形虫总感染率为６３９％ ,其中既往感染率为３５５％ ,新近感染率为２５１％ ,混合感染率为０３３％ 。不同年份间弓形虫感染率差异有高度显著性（Ｐ＜ ００１）,但不同职业间弓形虫感染率差异无显著性（Ｐ＞ ００５）,且ＨＢｓＡｇ 阳性与弓形虫感染无关（Ｐ＞ ００５）;乙酰螺旋霉素在治疗婚前妇女弓形虫感染中有一定作用。结论　对婚前妇女及孕产妇弓形虫感染的筛选和管理,将有利于控制和减少先天性弓形虫病的发生。     

艾滋病合并弓形虫感染研究进展

摘要:弓形虫（Toxoplasma gondii）是一种专性细胞内寄生的机会致病原虫,引起严重的人兽共患弓形虫病。在机体免疫功能正常情况下,弓形虫多为隐性感染,而在免疫缺陷人群如艾滋病患者,弓形虫可对患者的中枢神经系统、呼吸系统、消化系统、内分泌系统、心血管系统等产生不同程度的损害。艾滋病合并弓形虫感染的研究主要集中在流行病学调查和诊断方法、对机体的影响、动物模型研究和治疗药物等方面,本文就艾滋病合并弓形虫感染研究进展进行综述。     

Elevated Toxoplasma gondii Infection Rates for Retinas from Eye Banks,Southern Brazil

We found significantly higher incidence of Toxoplasma gondii DNA in eye bank specimens from Joinville in southern Brazil (13/15, 87%) than in São Paulo (3/42, 7%; p = 2.1 × 10E–8). PCR DNA sequence analysis was more sensitive at locus NTS2 than at locus B1; a high frequency of mixed co-infections was detected.     

酶联免疫法检测弓形体感染初探

目的酶联免疫法正确有效诊断弓形体急性感染。方法对4 500例无偿献血者血浆样本分别检测弓形体IgM抗体、IgG抗体,对IgM抗体阳性和IgM抗体阴性且IgG抗体阳性的样本检测其IgG抗体亲合力。结果 4 500例样本中,弓形体IgM抗体阳性率为0.51%,IgG抗体阳性率为1.53%。其中22例为IgM（＋）IgG（＋）,1例为IgM（＋）IgG（-）,47例为IgM（-）IgG（＋）,4 430例为IgM（-）IgG（-）。在对69例弓形体IgG（＋）的样本进行IgG亲合力检测时,IgM（＋）IgG（＋）的22例样本中2例为IgG中等亲合力抗体,3例为IgG高亲合力抗体,但这5例样本的IgM抗体均为可疑,可能由于IgM抗体常年保持低水平,并非正处于弓形体急性感染期;IgG（＋）IgM（-）的47例样本中,3例为IgG低亲合力抗体,可能由于其中的弓形体IgM抗体在急性感染期后期,IgM抗体滴度太低无法检测到,仍可判定为处于急性感染期。最终确定弓形体急性感染的样本为20例,感染率0.44%。结论可同时检测弓形体IgM抗体和弓形体IgG抗体亲合力来诊断弓形体感染,IgM抗体阳性或IgG抗体低亲合力的样本均可判定为弓形体急性感染。     

Production and Evaluation of Toxoplasma gondii Recombinant Surface Antigen 1 (SAG1) for Serodiagnosis of Acute and Chronic Toxoplasma Infection in Human Sera

Background

The assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the Lack of a purified standardized antigen. The aim of this study was evaluation the recombinant Toxoplasma gondii SAG1 antigen for the serodiagnosis of acute and chronic toxoplasmosis.

Methods

This study describes an ELISA using recombinant SAG1 for detection of IgM and IgG antibodies against Toxoplasma gondii in human sera. Genomic DNA of T. gondii (RH Strain) was isolated and PCR reaction was performed. Recovered DNA was cloned into PTZ57R cloning vector. The recombinant plasmid was detected by restriction analysis. The SAG1 gene was subcloned in the pET- 28a expression vector. Protein production was then induced with 1 mM isopropyl-D – thiogalactopyranoside (IPTG). A total of 204 sera were tested using a commercial IgG and IgM ELISA kit (Trinity, USA) as gold standard prior to testing them with the recombinant antigen.

Results

Tested sera were divided into the following groups:(a) The 74 T. gondii IgG positive (b) 70 T.gondii IgM positive (c) 60 sera who had no serological evidence of toxoplasmosis as negative sera.To determine the specificity of the test, we used other parasitic diseases including echinococusis (N=5), malaria (N=14), leishmaniasis (N=7),fasciolasis (N=4), sterengyloidiasis (N=1). Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (Com ELISA) were 93% and 95%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 87% and 95% respectively.

Conclusion

The results acquired here show that this antigen is useful for diagnostic purposes and could be replaced by lysed, whole cell antigens for diagnosis of chronic toxoplasmosis.     

Imported Haycocknema perplexum Infection,United States

We report an imported case of myositis caused by a rare parasite, Haycocknema perplexum, in Australia in a 37-year-old man who had progressive facial, axial, and limb weakness, dysphagia, dysphonia, increased levels of creatine kinase and hepatic aminotransferases, and peripheral eosinophilia for 8 years. He was given extended, high-dose albendazole.     

上海市不同人群弓形虫感染现状调查

[目的]了解上海市不同人群弓形虫感染现状及其影响因素。[方法]对健康人群、社区居民、肉品及动物密切接触者和恶性肿瘤患者4 169人用ELISA方法检测弓形虫IgG抗体,同时进行问卷调查。[结果]4组人群弓形虫感染率依次为3.30%、3.88%、5.40%和7.43%,组间差异有显著性(2χ=13.48,P<0.01)。不同性别、年龄、职业之间感染率差异无显著性(2χ=2.37~17.77,P>0.05),但感染率有随文化程度增高而下降的趋势(2χ=15.64,P<0.001)。家庭养猫同时养犬的居民弓形虫感染率(8.63%)显著高于不养宠物的家庭(3.74%)(2χ=11.44,P<0.001)。个人卫生习惯和行为良好者与不良者之间弓形虫感染率差异有显著性(2χ=4.23~12.71,P<0.05~0.001)。[结论]上海市不同人群组弓形虫的感染率均接近本市以往调查的平均水平,感染与家庭饲养宠物及不良卫生习惯有关。     

新兵人群弓形虫感染回顾性血清流行病学调查

弓形虫广泛感染人和动物,且多为隐性感染,并可通过胎盘感染胎儿,引起流产、死胎、先天畸形、出生缺陷等,已成为人类先天性感染中严重的疾病之一.为做好部队新兵人群弓形虫病的预防,随机抽取近4年入伍的360名新兵血清标本进行回顾性血清流行病学调查.     

南屯煤矿矿工弓形体感染的流行病学研究

以IHA检测弓形体抗体,1493名煤矿矿工弓形体感染率为7.70±0.69%。资料分析表明,养猫与弓形体感染之间有很强的联系(P﹤0.001,RR=9.95),接触猫是矿工弓形体感染的主要受染方式。在有妊娠和分娩史的妇女中,弓形体抗体阳性者发生不明原因流产的RR为4.95。     

Updated Estimates and Mapping for Prevalence of Chagas Disease among Adults,United States

We combined American Community Survey data with age-specific Trypanosoma cruzi prevalence derived from US surveys and World Health Organization reports to yield estimates of Chagas disease in the United States, which we mapped at the local level. In addition, we used blood donor data to estimate the relative prevalence of autochthonous T. cruzi infection. Our estimates indicate that 288,000 infected persons, including 57,000 Chagas cardiomyopathy patients and 43,000 infected reproductive-age women, currently live in the United States; 22–108 congenital infections occur annually. We estimated ≈10,000 prevalent cases of locally acquired T. cruzi infection. Mapping shows marked geographic heterogeneity of T. cruzi prevalence and illness. Reliable demographic and geographic data are key to guiding prevention and management of Chagas disease. Population-based surveys in high prevalence areas could improve the evidence base for future estimates. Knowledge of the demographics and geographic distribution of affected persons may aid practitioners in recognizing Chagas disease.     

育龄妇女维生素D缺乏与弓形虫感染的关联

目的探讨育龄妇女维生素D缺乏风险与弓形虫感染的关系。方法 2007—2010年,在河南省4个县开展育龄妇女围孕期风险因素暴露调查,采用多阶段随机抽样方法,建立育龄妇女孕前风险因素暴露的前瞻性队列,采用酶联免疫吸附法(ELISA)检测血清弓形虫抗体。2016年随访到有妊娠结局的妇女1151例,并测量该人群孕前血清标本中的维生素D水平。采用病例-对照研究方法,检验维生素D缺乏风险与弓形虫感染之间的关联。结果河南省育龄妇女维生素D缺乏率为61.5%(95%CI 59.2%～64.9%),弓形虫感染阳性率为9.6%(95%CI 7.9%～11.4%),其中IgG阳性、IgM阳性和两者均阳性者分别为7.6%、2.3%和0.3%。调整妇女教育程度、家庭年收入、食用禽蛋类和奶制品后发现,感染弓形虫的妇女维生素D缺乏的危险是未感染妇女的1.75倍(95%CI 1.11～2.77)。结论育龄妇女孕前感染弓形虫与其维生素D缺乏的风险存在关联。     

Severe Acquired Toxoplasmosis Caused by Wild Cycle of Toxoplasma gondii, French Guiana

From 1998 through 2006, 44 cases of severe primary toxoplasmosis were observed in French Guiana in immunocompetent adults. Toxoplasma gondii isolates exhibited an atypical multilocus genotype. Severe disease in humans may result from poor host adaptation to neotropical zoonotic strains of T. gondii circulating in a forest-based cycle.     

弓形虫感染对大鼠氧化应激与学习记忆能力影响

目的观察大鼠感染弓形虫后的学习记忆能力变化,并观测大鼠血清及脑组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、NO的变化。方法 48只雄性Wistar大鼠,分成弓形虫组与对照组,每组24只,弓形虫组腹腔注射2×107个/mL R H株弓形虫速殖子悬液2 mL,对照组腹腔注射灭菌生理盐水2 mL弓形虫组分别于感染后1、2、4、8周进行行为学测试,并检测血清及脑组织中SOD、MDA、NO含量。对照组大鼠分别于相同时间段检测上述指标。结果弓形虫与对照组大鼠时间、距离逃避潜伏期分别为(31.1±1.6)、(19.6±2.8)s和(1 066±3.2)、(772.0±6.9)cm,与对照组比较,弓形虫组大鼠潜伏期明显延长(P<0.05);弓形虫组大鼠血清、脑组织SOD分别为(91.2±8.3)、(78.9±3.2)U/mL,明显低于对照组(P<0.05);弓形虫组大鼠血清、脑组织MDA、NO含量分别为(22.1±1.3)、(7.8±2.0)nmol/mL和(21.5±3.1)、(29.9±1.8)μmol/mL,明显高于对照组(P<0.05)。结论大鼠感染弓形虫后学习记忆能力降低,可能与血清及脑内SOD活性降低、MD...     

Vectorborne Transmission of Leishmania infantum from Hounds,United States

Leishmaniasis is a zoonotic disease caused by predominantly vectorborne Leishmania spp. In the United States, canine visceral leishmaniasis is common among hounds, and L. infantum vertical transmission among hounds has been confirmed. We found that L. infantum from hounds remains infective in sandflies, underscoring the risk for human exposure by vectorborne transmission.     

孕妇弓形体感染与异常妊娠结局关系的前瞻性研究

对2 821名孕妇按弓形体感染情况分为三组,随访妊娠结局。结果发现,自然流产、早产、死胎和先天缺陷的总发生率分别为0.67%、3.47%、0.85%和0.96%。新近感染或活动性感染组这四种异常妊娠结局的发生率均显著高于未受感染组,相对危险度估计值(ORmh)分别为7.38、3.52,8.68和9.44。过去感染组与未受感染组异常妊娠结局的发生率差异均无统计学意义。抗体检出时间与异常妊娠结局发生的关系分析提示,先天缺陷的发生与孕三个月内感染有关。     

Norovirus Disease in the United States

Although recognized as the leading cause of epidemic acute gastroenteritis across all age groups, norovirus has remained poorly characterized with respect to its endemic disease incidence. Use of different methods, including attributable proportion extrapolation, population-based surveillance, and indirect modeling, in several recent studies has considerably improved norovirus disease incidence estimates for the United States. Norovirus causes an average of 570–800 deaths, 56,000–71,000 hospitalizations, 400,000 emergency department visits, 1.7–1.9 million outpatient visits, and 19–21 million total illnesses per year. Persons >65 years of age are at greatest risk for norovirus-associated death, and children <5 years of age have the highest rates of norovirus-associated medical care visits. Endemic norovirus disease occurs year round but exhibits a pronounced winter peak and increases by ≤50% during years in which pandemic strains emerge. These findings support continued development and targeting of appropriate interventions, including vaccines, for norovirus disease.