阴道铁线虫偶然寄生一例

铁线虫(Gordiacea Von Siebold,1843)为铁线虫纲蠕虫的总称.大多自由生活,偶可感染人体.笔者于2009年8月发现一例女性阴道寄生铁线虫,报告如下.     

2006～2010年扬州市邗江区李典沿江村农村居民肠道蠕虫感染情况分析

[目的]了解扬州市邗江区农村居民肠道蠕虫感染状况,为今后制定防治策略和措施提供科学依据。[方法]对2006～2010年邗江区李典沿江村3岁以上居民肠道蠕虫感染监测资料进行分析。[结果]2006～2010年累计检查6 411人次,检出肠道蠕虫阳性者73人,平均感染率为1.14%。其中,蛔虫感染率为0.62%,钩虫感染率为0.23%,鞭虫感染率为0.28%。肠道蠕虫感染率,2006年为5.72%,2007年为0.43%,2008年为0.40%,2009年为0.09%,2010年为0.00%(P<0.01)。[结论]邗江区农村居民肠道蠕虫感染率较低,并呈逐年下降趋势。     

The impact of sanitation on infectious disease and nutritional status: A systematic review and meta-analysis

Background

Sanitation aims to sequester human feces and prevent exposure to fecal pathogens. More than 2.4 billion people worldwide lack access to improved sanitation facilities and almost one billion practice open defecation. We undertook systematic reviews and meta-analyses to compile the most recent evidence on the impact of sanitation on diarrhea, soil-transmitted helminth (STH) infections, trachoma, schistosomiasis, and nutritional status assessed using anthropometry.

Genital schistosomiasis in women: a clinical 12-month in vivo study following treatment with praziquantel

Urinary schistosomiasis is known to be associated with lesions in the female genital organs, particularly with the presence of 'sandy patches' in the lower genital tract. This study sought to determine the effect of treatment with praziquantel on gynaecological schistosomiasis in residents of an area endemic for Schistosoma haematobium. A cohort study was conducted among women aged 20-49 years in rural Zimbabwe. The shape and size of lesions were mapped pre treatment and 3 and 12 months following treatment. Ova of S. haematobium were looked for in cytology smears, wet mounts, biopsies, urine and stool. Specimens were collected for detection of sexually transmitted diseases and cancer. At baseline, almost half of the 527 women included in the study had sandy patches. Although urinary ova excretion decreased following treatment (odds ratio 10.3, 95% CI 3.8-27.8, P<0.001), praziquantel treatment was not associated with a significant reduction in genital lesions or contact bleeding (P=0.31-0.94). Sandy patches remained strongly associated with contact bleeding and vessel abnormalities even after treatment. Findings were independent of HIV status. Such lesions, which are common and apparently refractory to treatment for at least 12 months, may be an important risk factor for both the acquisition and transmission of HIV.     

Is praziquantel therapy safe during pregnancy?

Schistosomiasis control programmes are generally based on mass distribution of praziquantel (PZQ). This approach has been further strengthened by studies that demonstrated reduction in schistosomiasis-related morbidity following regular use of PZQ. Many women were excluded from this therapy when pregnant. Since a high degree of parity is achieved in many schistosomiasis-endemic regions, excluded women often miss treatment and consequently the beneficial effect of this therapy. This study investigated the effect of PZQ therapy on pregnancy in the Gezira region of Sudan. As part of the Blue Nile Health Project, more than 320 000 individuals received annual treatment with PZQ from 1980 to1990. The present study reviewed the treatment records of all women between 1990 and 1995 in four villages. Eighty-eight of 637 women interviewed had received PZQ during their pregnancy. The outcome and the effect of PZQ therapy on their offspring were compared with a group of 549 women who had not received the drug during pregnancy. There were no significant differences between the two groups in the rate of abortion or preterm deliveries. No congenital abnormalities were noted by clinical examination in any of the babies born to either group. This retrospective study suggested that PZQ therapy is safe during pregnancy.     

血吸虫重复感染病人多次接受吡喹酮治疗效果评价

[目的]评价血吸虫重复感染病人多次接受吡喹酮抗虫治疗的效果。[方法]2004～2006年，在镇江市丹徒区江滩型血吸虫病流行区，对2000-2004年接受过吡喹酮抗虫治疗2次及以上的33名血吸虫重复感染病人，采用吡喹酮60mg／kg^2日疗法治疗，并评价其疗效。[结果]接受吡喹酮抗虫治疗6周后，粪便中均未检出血吸虫毛蚴；治疗后第24个月血清血吸虫特异性抗体阳性率由治疗前的100.00%下降至25.24%；治疗2年后B超检查肝脾肿大和肝实质损害的改善不明显。[结论]血吸虫重复感染病人多次接受吡喹酮抗虫治疗效果明显。     

Regular treatments of praziquantel do not impact on the genetic make-up of Schistosoma mansoni in Northern Senegal

The Senegal River Basin (SRB) experienced a major epidemic of intestinal schistosomiasis in the early nineties, after the construction of a dam for irrigation purposes. Exceptionally low cure rates following praziquantel (PZQ) treatment at the onset of the epidemic raised concerns about PZQ resistant strains of Schistosoma mansoni, although they could also be attributed to the intense transmission at that time. A field study in the same region more than 15 years later found cure rates for S. mansoni still to be low, whereas Schistosomahaematobium responded well to treatment. We collected S. mansoni miracidia from children at base-line prior to treatment, six  months after two PZQ treatments and   two years after the start of the study when they had received a total of five PZQ treatments. In total, 434 miracidia from 12 children were successfully genotyped with at least six out of nine DNA microsatellite loci. We found no significant differences in the genetic diversity of, and genetic differentiation between parasite populations before and after repeated treatment, suggesting that PZQ treatment does not have an impact on the neutral evolution of the parasite. This is in stark contrast with a similar study in Tanzania where a significant decrease in genetic diversity was observed in S. mansoni miracidia after a single round of PZQ treatment. We argue that PZQ resistance might play a role in our study area, although rapid re-infection cannot be excluded. It is important to monitor this situation carefully and conduct larger field studies with short-term follow-up after treatment. Since PZQ is the only general schistosomicide available, the possibility of PZQ resistance is of great concern both for disease control and for curative use in clinical practice.     

新型吡喹酮薄膜衣片治疗日本血吸虫病的副反应及疗效研究

目的 了解新型吡喹酮薄膜衣片治疗日本血吸虫病的副反应状况及治疗效果.方法 在湖北、江西、安徽血吸虫病流行区选择6～65岁的常住居民进行问卷调查、间接血凝免疫诊断试剂筛查,血检阳性者进行改良加藤法检查以确诊.对血检阳性者及部分自愿服药的正常人共计509名给服吡喹酮并调查药物的味道,对460例服药前无副反应相关症状的化疗对象随访副反应情况,对104例粪检阳性者在化疗后3个月进行疗效考核.结果 84.7%(144/170)的被调查者认为新型吡喹酮薄膜衣片没有味道或者很轻,而吡喹酮素片对照组有92.9%(315/339)的被调查者认为药物味道较重.在化疗后1～2 h,新型吡喹酮薄膜衣片化疗组副反应率为20.30%(27/133),吡喹酮素片对照组副反应率为83.18%(272/327),两化疗组间副反应率具有统计学意义(χ2=164.316,P<0.05).其中新型吡喹酮薄膜衣片化疗组在神经肌肉系统、消化系统、心血管系统的副反应率分别为15.79%(21/133)、9.77%(13/133)、2.26%(3/133),而吡喹酮素片对照组在神经肌肉系统、消化系统、心血管系统的副反应率分别为81.65%(267/327)、49.24%(161/327)、12.84%(42/327),3个系统的副反应率在两化疗组间均具有统计学意义(χ2神经肌肉系统=175.188,χ2消化系统=62.601,χ2心血管系统12.010,P值均<0.05);吡喹酮薄膜衣片化疗组、素片对照组过敏反应发生率分别为2.26%(3/133)、0.92%(3/327),两者之间无统计学意义(χ2=1.315,P=0.235).化疗后第2天吡喹酮薄膜衣片化疗组和素片对照组的副反应率分别下降为3.01%(4/133)、38.53%(126/327),两组间存在统计学意义(χ2=58.852,P<0.05).在化疗后2周新型吡喹酮薄膜衣片化疗组、素片对照组的副反应率均已分别下降为0.75%(1/133)、0.61%(2/327),两组间已无统计学意义(χ2=0.029,P=0.642).化疗后3个月新型吡喹酮薄膜衣片化疗组、素片对照组的粪检阴转率分别为84.91%(45/51)、82.135%(42/53),两组间无统计学意义(χ2=1.536,P=0.215).结论 新型吡喹酮薄膜衣片降低了味道及化疗对象的副反应发生率,其疗效与吡喹酮素片对照组等效.在进一步扩大现场验证的基础上,可在血吸虫病流行区推广使用.     

Field testing of the WHO dose pole for administration of praziquantel in the treatment of opisthorchiasis in Lao PDR

In 2001, the WHO developed a dose pole that employs height measurements for estimation of the dose of praziquantel. In the present study, conducted in December 2005 during a mass treatment campaign for the control of opisthorchiasis in 232 individuals in Nala village, Keo Udom district, Lao PDR, performance of the dose pole in estimating dosages of praziquantel was compared with a bathroom scale; a digital scale was used as the gold standard. Results showed that the bathroom scale performed significantly better than the dose pole in delivering dosages of 40-50 mg/kg for opisthorchiasis treatment (70.7% vs. 44.8%). Furthermore, the dose pole performed significantly better for children than adults. The reason for the poor performance of the dose pole among adults is likely to be due to the high percentage (19.4%) of overweight individuals in the adult population of the village. It was concluded that the WHO dose pole is not recommended for distribution of praziquantel for the treatment of opisthorchiasis in populations where being overweight is common.     

Progress towards countrywide control of schistosomiasis and soil-transmitted helminthiasis in Uganda

Schistosomiasis caused by infection with Schistosoma mansoni is a serious public health burden in 38 of the 56 districts of Uganda. This article reviews the initial experience of the national control programme. Launched in 2003, this started with a pilot phase with the main aim of utilizing the experience to formulate feasible and appropriate methods of drug delivery. Overall, 432,746 people were treated and coverage was 91.4% in schools and 64.7% in communities. The issues raised by independent evaluators included that most communities did not participate in the selection of community drug distributors (CDD) and that teachers and CDDs needed refresher training mainly on health education and the management of side effects. As a way forward, it is suggested that the Ministry of Health should integrate deworming into the existing health infrastructure so that every time a child is reached for any health service, the child is also de-wormed.     

Comparison of different anthelminthic drug regimens against Mansonella perstans filariasis

Mansonella perstans filariasis is widely present in Africa and equatorial America and its pathogenicity has recently been reconsidered. Effective treatment is lacking and there is no consensus on the optimal therapeutic approach. The aim of this study was to compare the effects of different drug regimens on M. perstans infection. Six different anthelminthic therapeutic protocols were undertaken on 165 subjects with M. perstans infection and their effects on microfilariae burden were evaluated. Diethylcarbamazine (DEC) was able to reduce microfilariae density in the majority of cases, but it seldom eliminated infection after a single treatment. Mebendazole appeared to be more active than DEC in eliminating the infection, with a comparable rate of overall responses. Ivermectin and praziquantel showed no modification of microfilariae concentration. Thiabendazole showed a small but significant activity against the infection. Combination treatments (DEC plus mebendazole) resulted in a significantly higher activity than the single drugs.     

洞庭湖傍山移民建镇地区血吸虫病疫情变化研究

目的 查明傍山移民建镇地区环境改变对血吸虫病流行因素的影响及疫情变化趋势。方法 采用试点现场调查和实验室检查相结合的方法，观测人、畜血吸虫病感染、钉螺分布、环境因素等变化情况。结果 傍山移民建镇后，居民点距易感地带变远，居民血吸虫病感染率呈下降趋势；由于人畜粪便污染减少，易感地带感染性钉螺密度下降。结论 傍山移民建镇对控制血吸虫病疫情有积极意义。     

Efficacy and side effects of praziquantel against Schistosoma mansoni in a community of western Côte d'Ivoire

Praziquantel is efficacious against the adult stages of all human schistosome parasites, and has become the drug of choice for morbidity control of schistosomiasis. There is concern that resistance to praziquantel might develop or already exists, and could be further facilitated through new control initiatives relying on large-scale administration of praziquantel. Therefore, monitoring praziquantel efficacy in different epidemiological settings is required. We assessed the efficacy and side effects of praziquantel against Schistosoma mansoni in a rural community of western C?te d'Ivoire. Three consecutive stool specimens from 545 children and adults were examined by the Kato-Katz technique, revealing an overall prevalence of 40.9%. S. mansoni-infected individuals were treated with a single oral dose of praziquantel at 40 mg/kg. The most frequent side effects were abdominal pain, dizziness and diarrhoea. The overall cure rate, assessed 6 weeks post-treatment, was 60.9%. Moderate or heavy infections were only cleared in half or one-third of the individuals, respectively. The total egg count reduction was 61.4%. Infection intensity pre-treatment was significantly associated with age, cure rate, reported diarrhoea and dizziness. Our findings call for additional studies that rigorously evaluate the efficacy of praziquantel against different schistosome species in entire communities, using similarly sensitive diagnostic approaches as employed here.     

New vaccines against hepatitis B

The high cost and limited availability of the plasma-derived hepatitis B vaccines have prevented their widespread use, especially in the less developed areas where they are needed most. Hepatitis B vaccines produced by recombinant technology seem to offer a solution to these difficulties. Studies reported up to now confirmed the safety of this vaccine. Immunogenicity studies in various population groups showed that seroconversion rates and antibody titres are comparable to plasma vaccine. In assessing the efficacy of the vaccine, information concerning the quality of the anti-HBs induced should complement these data. Potential live vaccines using recombinant vaccinia viruses have been constructed for hepatitis .B. Preliminary studies in rabbits and chimpanzees indicated the feasibility of future using a recombinant vaccinia virus.Chemically synthesized polypeptides corresponding to relevant epitopes of HBsAg may be useful as synthetic vaccines offering the advantages of a cheap viral immunogen free from irrelevant antigenic determinants.Finally preliminary studies for an idiotypic vaccine have already been reported.     

Protection against Schistosoma haematobium infection in hamsters by immunization with Schistosoma mansoni gut-derived cysteine peptidases,SmCB1 and SmCL3

We examined the immunogenicity and protective potential of SmCB1 and SmCL3 cysteine peptidases, alone and in combination, in hamsters challenged with S. haematobium. For each of two independent experiments, eight Syrian hamsters were immunized twice with a three week-interval with 0 (controls), 20 µg SmCB1, 20 µg SmCL3, or 10 µg SmCB1 plus 10 µg SmCL3, and then percutaneously exposed eight weeks later to 100 S. haematobium cercariae. Hamsters from each group were assessed for humoral and whole blood culture cytokine responses on day 10 post challenge infection, and examined for parasitological parameters 12 weeks post infection. At day 10 post-infection we found that SmCB1 and SmCL3 elicited low antibody titres and weak but polarized cytokine type 2 responses. Nevertheless, both cysteine peptidases, alone or in combination, evoked reproducible and highly significant reduction in challenge worm burden (>70%, P < 0.02) as well as a significant reduction in worm egg counts and viability. The data support our previous findings and show that S. mansoni cysteine peptidases SmCB1 and SmCL3 are efficacious adjuvant-free vaccines that induce protection in mice and hamsters against both S. mansoni and S. haematobium.