海拔3700m移居青年睡眠呼吸暂停低通气综合征患病率调查

目的了解高原移居青年睡眠呼吸暂停低通气综合征(SAHS)的患病率,为制定该病的防治策略提供依据。方法对移居海拔3 7 0 0 m的某部官兵进行睡眠问卷调查,分别统计不同年龄、移居高原不同时间、进入高原不同次数人群中打鼾的发生率,并对被调查者白天的嗜睡情况进行评分。结果在调查的433人中打鼾的发生率为48.96%,其中中、重度打鼾者占16.86%。随着移居时间的延长,鼾症发生率有不同程度的增加,尤其是移居6个月以上青年轻、重度打鼾发生率增高明显(χ2=12.774,P=0.047)。进入高原环境1次以上者较首次进入高原者打鼾发生率有所增高,尤其是轻、中度鼾症较为明显,但在统计学上无显著性意义(χ2=7.295,P=0.063)。不同程度的打鼾患者,日间的嗜睡评分有非常显著性差异(F=16.765,P=0.000)。结论如果仅依日间Epworth嗜睡量表(ESS)评分≥9分为标准,保守估计海拔3 700 m高原移居青年SAHS的患病率为11.55%,是影响高原移居者健康的重要问题之一,应当引起足够的重视。

641名食品从业人员肺结核调查报告

目的研究民族贫困地区食品从业人群中肺结核病的发病情况,探讨防治对策,保证食品从业人员身体健康。方法对641名食品从业人员进行健康体检,并作肺部X线摄片检查。结果 2010年食品从业人员体检641名,检出肺结核病5例,检出率7.8%。其中:男性3例,女性2例,男女之比为1.5:1;年龄最大46岁,最小26岁,平均39.5岁,﹤30岁发病3例占60%;查出三型5例(其中肺部空洞1例占20%)占100%;两侧肺部发病3例占60%,痰涂片检查抗酸杆菌4例,痰检率80%(4/5),痰结核杆菌检出阳性1例,菌阳检出率25%(1/4)。结论食品从业人群中肺结核病检出率很高,应加强《中华人民共和国食品安全法》的宣传和执法力度,增强食品从业人员法制观念。对查出肺结核的从业者,除调离食品从业岗位外,应动员患者早期、足量、全程、彻底有效的抗痨治疗,消除传染源,同时在食品从业人群中大力宣传肺结核病的防治知识,才能控制边远少数民族贫困地区肺结核病的发生与流行。

广州市萝岗区盲与低视力流行病学调查

目的调查广州市萝岗区年龄≥50岁人群肓与低视力的患病率及主要致病原因。方法采用整群抽样方法，按世界卫生组织肓与低视力分类标准，对广州市萝岗区50岁及以上人群进行问卷调查，视力检测初筛后对针孔镜下视力低于0．3者，由眼科医师做视功能、眼前后节形态检查及主要致肓原因诊断。结果共录入人数4532人，实际受检4126人，受检率91．04％。其中双眼肓患病率为1．91％，单眼盲患病率5．96％，双眼低视力患病率8.41％。随着年龄增加，肓与低视力患病率明显升高，70岁年龄组双眼肓是50岁年龄组的25．5倍，差异具有统计学意义（P〈O．01）。在肓与低视力人群中致病原因的前几位依次是白内障（47．9％），眼底病（20.4％），屈光不正（9．52％），角膜病（7．59％）。另外，脑垂体瘤致肓占0．74％。结论广州市萝岗区≥50岁老年人群盲与低视力的首要原因为白内障，故降低白内障的患病率是该地区防肓治盲的关键，另外眼底病在该地区也是重点防治的疾病。

Epidemiological Investigation of Actinobacillus Pleuropneumoniae in Western Shandong

[ Objective ] The aim of this study was to investigate the epidemic status of porcine pleuropneumonia in western Shandong and establish the PCR method of actinobacillus pleuropneumoniae （APP）. [ Method] The epidemic status of APP in lesion tissues of 186 death pigs and 545 health pigs without clinical symptoms was analyzed by PCR method. [ Result] APP positive rate in 186 samples accounted for 43.0% （80/186）, while that in 545 porcine serums accounted for 9.4% （51/545）. [ Conclusion] This PCR method can be used as one of the important means for APP clinical diagnosis.

Epidemiological survey of cryptosporidiosis in Anhui Province China

AIM: To provide scientific evidence for prevention and controlling of cryptosporidiosis, the infection of Cryptosporidium parvum and its epidemiological characteristics were studied in some areas of Anhui Province. METHODS: The oocyst of Cryptosporidium parvum in 5421 fresh stool samples from eleven areas of Anhui Province was tested by auramine-phenol stain and improved anti-acid stain respectively. The specific antibody of IgG, IgM and T subsets of 41 patients with positive Cryptosporidium parvum in stools were detected by ELISA and biotin-streptavidin (BSA) respectively. RESULTS: The total infective rate of Cryptosporidium parvum was 1.33% (74/5421). Among them, the positive rates of oocyst in the areas of Huaibei (1.82%) and Fuyang (1.80%) were higher. The positive rates of oocyst in stools of infants, pupils, middle school students, college students, adults, patients with diarrhea, and those with immunodeficiency were 3.15%(28/889), 0.82% (9/1098), 0.82%(9/1092), 0.83%(8/969), 0.85% (9/1095), 2.88%(8/278) and 8.33%(3/36)% respectively. The positive rates of oocyst in infants and the patients with diarrhea and immunodeficiency were significantly higher than those in controls (P【0.01). The positive rate of oocyst in males was similar to that in females (P】0.05). The positive rate of oocyst in urban areas (1.13%) was significantly lower than those in rural areas (1.72%, P【0.01). The positive rates of specific IgG, IgM and IgG+IgM in sera of the patients with positive oocyst in stool were 63.4% (26/41), 17.1% (7/41), 19.5% (8/41) respectively. The number fractions of T subsets of CD(3)(+), CD(4)(+), CD(8)(+) and CD(4)(+)/CD(8)(+) of the patients were 0.66+/-0.07, 0.44+/-0.06, 0.28+/-0.04 and 1.58+/-0.32 respectively. The difference between the patients and the controls was significant (P【0.05). The main manifestations of the patients were subclinical infection, in forms of slight abdominal pain, mild diarrhea, and loose stool. CONCLUSION: There are two infection peaks in infection of Cryptosporidium parvum and its infection can be found more often in infants, patients with diarrhea or immunodeficiency, and in rural areas. Subclinical infection is the main manifestation and might be easily misdiagnosed. When the therapeutic effectiveness is low for diarrhea, the infection of Cryptosporidium parvum should be considered, concerning their age and immune function.

Reassessment of functional dyspepsia:From the editor

Dyspepsia refers to group of upper gastrointestinal symptoms that occur commonly in adults. Dyspepsia is known to result from organic causes, but the majority of patients suffer from non-ulcer or functional dyspepsia. Epidemiological data from population-based studies of various geographical locations have been reviewed, as they provide more realistic information. Population-based studies on true functional dyspepsia （FD） are few, due to the logistic difficulties of excluding structural disease in large numbers of people. Globally, the prevalence of uninvestigated dyspepsia （UD） varies between 7%- 45%, depending on definition used and geographical location, whilst the prevalence of FD has been noted to vary between 11%-29.2%. Risk factors for FD have been shown to include females and underlying psychological disturbances, whilst environmental/lifestyle habits such as poor socio-economic status, smoking, increased caffeine intake and ingestion of non-steroidal anti-inflammatory drugs appear to be more relevant to UD. It is clear that dyspepsia and FD in particular are common conditions globally, affecting most populations, regardless of location.

Human papillomavirus in squamous cell carcinoma of esophagus in a high-risk population

AIM: To investigate the relation of human papillomavirus (HPV) and esophageal squamous cell carcinoma (ESCC) in Iranian patients as compared to normal controls. METHODS: Using MY09/MY11 consensus primers, we compared the prevalence of a HPV L1 gene in tumor tissues from 38 ESCC cases and biopsied tissues from 38 endoscopically normal Iranian individuals. We also compared the presence of HPV16 and HPVA18 in the same samples using type-specific E6/E7 primers. RESULTS: Fourteen (36.8%) of the 38 ESCC samples but only 5 (13.2%) of the 38 control samples were positive for the HPV L1 gene (P= 0.02). Five (13.2%) of the ESCC samples but none of the control samples were positive for the HPV16 E6/E7 gene (P= 0.05). Three (7.9%) of the ESCC samples and 5 (13.2%) of the control samples were positive for the HPV18 E6/E7 gene (P= 0.71). CONCLUSION: Our data are consistent with HPV DNA studies conducted in other high-risk areas for ESCC. HPV should be considered as a potential factor contributing to the high incidence of ESCC in Iran and other high-incidence areas of the world.

Epidemiology and outcome of Crohn's disease in a teaching hospital in Riyadh

AIM: To know the epidemiology and outcome of Crohn's disease at King Khalid University Hospital, Riyadh, Saudi Arabia and to compare the results from other world institutions.METHODS: A retrospective analysis of patients seen for 20 years (between 1983 and 2002). Individual case records were reviewed with regard to history, clinical, findings from colonoscopy, biopsies, small bowel enema, computerized tomography scan, treatment and outcome.RESULTS: Seventy-seven patients with Crohn's disease were revisited, 13% presented the disease in the first 10 years and 87% over the last 10 years. Thirty-three patients (42.9%) were males and 44 (57.1%) were females. Age ranged from 11-70 years (mean of 25.3+11.3 years). Ninety-two (92%) were Saudi. The mean duration of symptoms was 26+34.7 mo. The mean annual incidence of the disease over the first 10 years was 0.32:100 000 and 1.66:100 000 over the last 10 years with a total mean annual incidence of 0.94:100 000 over the last 20 years. The chief clinical features included abdominal pain, diarrhea, weight loss,anorexia, rectal bleeding and palpable mass. Colonoscopic findings were abnormal in 58 patients (76%) showing mostly ulcerations and inflammation of the colon. Eighty nine percent of patients showed nonspecific inflammation with chronic inflammatory cells and half of these patients revealed the presence of granulomas and granulations on bowel biopsies. Similarly, 69 (89%) of small bowel enema results revealed ulcerations (49%), narrowing of the bowel lumen (42%), mucosal thickening (35%) and cobblestone appearance (35%). CT scan showed abnormality in 68 (88%) of patients with features of thickened loops (66%) and lymphadenopathy (37%). Seventy-eight percent of patients had small and large bowel disease, 16% had small bowel involvement and only 6% had colitis alone. Of the total 55 (71%) patients treated with steroids at some point in their disease history, a satisfactory response to therapy was seen in 28 patients (51%) while 27 (49%) showed recurrences of the condition with mild to moderate symptoms of abdominal pain and diarrhea most of which were due to poor compliance to medication. Seven patients (33%) remained with active Crohn's disease. Nine (12%) patients underwent surgery with resections of some parts of bowel, 2 (2.5%) had steroid side effects, 6 (8%) with perianal Crohn's disease and five (6.5%) with fistulae.CONCLUSION: The epidemiological characteristics of Crohn's disease among Saudi patients are comparable to those reported from other parts of the world. However the incidence of Crohn's disease in our hospital increased over the last 10 years. The anatomic distribution of the disease is different from other world institutions with less isolated colonic affection.

Epidemiological Investigation and Genome Analysis of Duck Circovirus in Southern China

Duck circovirus （DuCV）, a potential immunosuppressive virus, was investigated in Southern China from March 2006 to December 2009 by using a polymerase chain reaction （PCR） based method. In this study, a total of 138 sick or dead duck samples from 18 different farms were examined with an average DuCV infection rate of-35%. It was found that ducks between the ages of 40~60 days were more susceptible to DuCV. There was no evidence showing that the DuCV virus was capable of vertical transmission. Farms with positive PCR results exhibited no regularly apparent clinical abnormalities such as feathering disorders, growth retardation or lower-than-average weight. The complete genomes of 91 strains from Fujian Province and 1 from Zhejiang Province were sequenced and analyzed. The 10 DuCV genomes, comlbared with others genomes downloaded from GenBank, ranged in size from 1988 to 1996 base pairs, with sequence identities ranging from 83.2% to 99.8%. Phylogenetic analysis based on genome sequences demonstrated that DuCVs can be divided into two distinct genetic genotypes, Group I （the Euro-USA lineage） and Group II（the Taiwan lineage）, with approximately 10.0% genetic difference between the two types. Molecular epidemiological data suggest there is no obvious difference among DuCV strains isolated from different geographic locations or different species, including Duck, Muscovy duck, Mule duck, Cheery duck, Mulard duck and Pekin duck.

Incidence of gallstone disease in Italy:Results from a multicenter,population-based Italian study (the MICOL project)

AIM:To evaluate gallstone incidence and risk factors in a large population-based study. METHODS: Gallstone incidence and risk factors, were evaluated by structured questionnaire and physical examination, respectively, in 9611 of 11 109 (86.5%) subjects who were gallstone-free at the cross-sectional study. RESULTS: Six centers throughout Italy enrolled 9611 subjects (5477 males, 4134 females, aged 30-79 years), 9517 of whom were included into analysis: 424 subjects (4.4%) had gallstones and 61 (0.6%) had been cholecystectomized yielding a cumulative incidence of 0.67% per year (0.66% in males, 0.81% in females). Increasing age, a high body mass index (BMI), a history of diabetes, peptic ulcer and angina, and low cholesterol and high triglyceride levels were identifi ed as risk factors in men while, in females, the only risk factors were increasing age and a high BMI.Increasing age and pain in the right hypocondrium in men and increasing age in females were identifi ed as predictors of gallstones. Pain in the epigastrium/ right hypocondrium was the only symptom related to gallstones; furthermore, some characteristics of pain (forcing to rest, not relieved by bowel movements) were significantly associated with gallstones. No correlation was found between gallstone characteristics and clinical manifestations, while increasing age in men and increasing age and BMI in females were predictors of pain. CONCLUSION:Increasing age and BMI represent true risk factors for gallstone disease (GD); pain in the right hypocondrium and/or epigastrium is confi rmed as the only symptom related to gallstones.

Complete Genome Sequence Analysis of Duck Circovirus Strains from Cherry Valley Duck

To investigate molecular epidemiology of DuCV in Cherry Valley ducks in China, the complete genomes of six DuCV strains, which were detected from Cherry Valley ducks in China between 2007 and 2008, were sequenced. Sequence and phylogenetic analysis were carried out to compare these six strains with another 27 DuCV strains from Mulard duck, Muscovy duck, Pekin ducks and Mule duck. The analysis showed that the six DuCV strains exhibited typical genetic features of the family of DuCV, such as a stem-loop structure, three major open reading frames (Rep, Cap and ORF3), four intergenic repeats and the conserved motifs for rolling circle replication and for the dNTP binding domain located in the Rep protein. Phylogenetic analysis of the nucleotide sequences of the complete genome and Cap gene of these strains together with those that have been previously published demonstrated two distinct DuCV genotypes. The DuCV strains with complete genomes containing 1988 and 1989 nucleotides clustered in genotype A, whereas the strains with complete genomes containing 1991, 1992, 1995 and 1996 nucleotides lay in genotype B. The six DuCV strains from Cherry Valley ducks were divided into the two groups. The results of the study provides some insight into the variation of DuCVs in Cherry Valley ducks.

Clinical and epidemiological features of patients with clonorchiasis

AIM:To study the clinical and epidemiological features of patients with clonorchiasis so as to provide scientific evidences for the diagnosis and prevention of clonorchiasis. METHODS:Stools from 282 subjects suspected of having clonorchiasis were examined for helminth eggs with modified Kato's thick smear and sedimentation methods,and their sera were tested for HAV-DNA,HBV-DNA,HCV-RNA,HDV- RNA and HEV-RNA with polymerase chain reaction (PCR). Clinical symptoms of patients with clonorchiasis only were analyzed,and their blood samples were tested for circulating antigen (CAg) with Dot-ELISA,esoinophilic granulocyte count, and alanine aminotransferase (ALT).Meanwhile,they were asked to provide data of occupation,eating habit,hygienic habit and knowledge of donorchiasis.In addition,the ecosystem of the environment in epidemic areas was surveyed. RESULTS:Among the 282 patients,61 (21.43%) were infected with clonorchis sinensis only,97 (34.64%) were co-infected with clonorchis sinensis and other pathogens, 92 (32.86%) were infected with hepatitis virus only and 31 (11.07%) neither with clonorchis sinensis nor hepatitis virus. Among the 61 patients with clonorchiasis only,there were 14 (22.95%) subjects with discomfort over hepatic region or epigasfrium,12 (19.67%) with general malaise or discomfort and inertia in total body,6 (9.84%) with anorexia,indigestion and nausea,4 (6.56%) with fever,dizziness and headache (6.56%),and 25 (40.98%) without any symptoms;sixty one (100%) with CAg (+),98.33% (59160) with eosinophilic granulocytes increased and 65.00% (39/60) with ALT increased.B-mode ultrasonography revealed 61 cases with dilated and thickened walls of intrahepatic bile duct,and blurred patchy echo acoustic image in liver.Twenty-six cases had stones in the bile duct,39 cases had slightly enlarged liver with diffuse coarse spots in liver parenchyma.Twenty cases had enlarged gallbladder with thickened coarse wall and image of floating plagues,9 cases had slightly enlarged spleen.By analysis of epidemiological data,we found that the ecologic environment was favorable for the epidemiology of clonorchiasis.Most patients with clonorchiasis were lack of knowledge about the disease.Their living environment, hygienic habits,eating habits and their occupations were the related factors that caused the prevalence of the disease. CONCLUSION:The clinical symptoms of clonorchiasis are non-specific,and the main evidences for diagnosis of clonorchiasis should be provided by etiologic examination, B-mode ultrasonography and clinical history.The infection of clonorchis sinensis is related to occupations,bad eating habits and lack of knowledge about prevention of the disease.

NATIONAL SURVEY ON PREVALENCE OF CANCER PAIN

Objective. To collect nationwide basic data about cancer related pain. Methods. Sixty cancer patients in each province were randomly selected to participate in this survey. The subjects represented all stages of cancer, tumor sites, and different demographic characteristics. Two self- designed structured questionnaires including reasons, types of pain and pain management were used by patients and physicians respectively. Subjects were asked to report whether he/she had experienced any type of cancer related pain and filled out the equivalent questionnaire. The severity of pain was assessed by using“ visual analogue scale” . Original data input and analysis were using EPI- INFO software package. Results. The result showed that 61.6％ (958/1555) of patients had different types of cancer related pain. Majority of pain (85.1％ ) were caused by advanced cancer. The major reasons (64.4％ ) for poor management or impedimental factors of pain care are due to patient including over- concern on opioid analgesic addiction, reluctance to report pain or refused to use opioid analgesic until at times when pain is intolerable; 26.8％ belonged to physician’s reasons including fear to cause addiction on opioid and lack of knowledge about cancer pain management; 16.2％ are due to lack of different kinds of opioid analgesic for use and 16.1％ belonged to drug regulation. Conclusions. The results showed that majority of patients (61.6％ ) had different types of cancer related pain. In most of patients, cancer pain was relieved when they were treated. The major reason for under- treatment or impeded factors for effective relief of cancer pain was fear of opioid addiction by both medical professionals and patients.

Development of Multiple ELISAs for the Detection of Antibodies against Classical Swine Fever Virus in Pig Sera

The major immunogenic proteins （Ems, E2 and NS3） of classical swine fever virus （CSFV） （Shimen strain） were expressed in E. coli and purified by affinity chromatography. The recombinant antigens were applied to develop multiple enzyme-linked immunosorbent assays （ELISAs） for the detection of specific antibodies in pig sera. Optimum cut-off values were determined by receiver operating characteristic （ROC） analysis after testing 201 sera of vaccinated pigs and 64 negative sera of unvaccinated piglets. The multiple ELISAs were validated with 265 pig sera yielding high sensitivity and specificity in comparison with the virus neutralization results. The results demonstrated that multiple ELISAs can be a valuable tool for the detection of CSFV infection and serological surveys in CSFV-free countries or for the evaluation of the antibody responses in pigs induced by a live attenuated C-strain vaccination

Epidemiological investigation of Barrett's esophagus in patients with gastroesophageal reflux disease in Northwest China

Objective： To investigate the prevalence and possible risk factors of Barrett＇s esophagus （BE） in patients with gastroesophageal reflux disease （GERD） in Northwest China. Methods： Patients older than 18 years who underwent regular health check-up or had upper gastrointestinal symptoms in the endoscopy centers of four major teaching hospitals located in four different provinces of Northwest China from September 2008 to February 2009 were included in the study. A face-to-face reflux diagnostic questionnaire including risk factors were taken and scale scores （So） were accumulated. Diagnostic criterion of GERD was Sc≥12 points. None of these subjects received anti-acid medication prior to their endoscopy done. Barrett＇s esophagus was diagnosed when specialized intestinal metaplasia was detected histologically. Results： A total of 528 patients met the criteria of GERD, among which 32 patients （20 male and 12 female） were diagnosed with BE. BE was present in 6.06% with a mean age of 51.2±11.6 years, which was significantly older than patients with GERD without BE （46.6±13.3 years） （P〈0.05）. There weresignificant differences between BE and GERD patients regarding gender, age, hiatus hernia, smoking and alcohol consumption （P〈0.05）, while no significant difference regarding symptoms of GERD. There was significant difference between short segment Barrett＇s esophagus and long segment （65.6% vs 34.4%, P〈0.05）. Conclusion： The prevalence of BE was 6.06% in patients with GERD in northwest China and was dominated by SSBE. The potential risk factors of Barrett＇s esophagus were older age, male, esophageal hiatal hernia, smoking and alcohol consumption.

AN EPIDEMIOLOGICAL SURVEY OF CHOLELITHIASIS IN SHANGHAI

Objective To obtain a general overview of gallstone disease in Shanghai. Methods 3415citizens aged >20 in the community of Shanghai were randomly selected to undergo a clinical epidemiological study and an ultrasound examination to screen for cholelithiasis. Results Overall prevalence rate of gallstones was 6.5% (8.6% in women and 5.1% in men). Among the 3415 persons investigated, 65 had already undergone cholecystectomy. The percentage of asymptomatic gallstone was 70 .5% . Prevalence of gallstone diseases (gallstones plus cholecystectomy) increased with age significantly. Conclusion Compared to the research in Shanghai ten years ago, especially for the persons older than 50 years, the gallstone disease has become more frequent. The proportion of asymptomatic gallstones and the awareness is increasing.

Prevalence and clinical significance of SEN virus infection in patients with non A-E hepatitis and volunteer blood donors in Shanghai

AIM:To explore the prevalence of SEN virus (SENV) in patients with non A-E hepatitis and volunteer blood donors in Shanghai. METHODS: According to the published gene sequences, primers from the conserved region were designed. Then, the prevalence of SEN virus in 30 samples from healthy voluntary blood donors and 30 samples from patients with non A-E hepatitis were detected by nested-PCR of SENV-D/H. Some PCR products were cloned and sequenced. RESULTS: The specificity of genotype-specific PCR was confirmed by sequencing, the SENV DNA was detected in 53.3% of the patients with non A-E hepatitis and 10% of the blood donors. The prevalence of SENV-D/H viremia was significantly higher in patients with non A-E hepatitis than in blood donors (P = 0.0002). SENV-H subtype and SENV-D subtype were found in 2 and 1 samples, respectively from blood donors. SENV-H subtype, SENV D subtype, mixed SENV-D and SENV-H subtype were found in 8, 6 and 2 samples, respectively, from patients with non A-E hepatitis. CONCLUSION: The gene type of SENV in patients with non A-E hepatitis and blood donors in shanghai is D or H subtype, and transfusion is not the only transmitting form of SENV.

Prevalence and Characteristics of Pregnant Syphilis among Women Attending Antenatal Clinics in Shenzhen (China) in 2003

Background: The Nnewly reported cases ofcongenital syphilis have been increaseding substantiallyover the past few years. To control the epidemic, a mu-nicipal program aimed at preventing mother-to-childtransmission of syphilis was introduced in July, 2001,which was designed aimed to screen all pregnant womenfor syphilis at their first visit to antenatal clinics or atadmission to hospitals in Shenzhen.Objectives: The aim of the study is tTo determine theprevalence of syphilis among women attending antenatalclinics and other medical institutions in Shenzhen andidentifies its patterns of infection. Methods: Upon giving informed consent, w Women whoattended antenatal care centers in Shenzhen from Janu-ary to December 2003 were included in this study subjectto obtaining informed consent. A blood sample was har-vested for syphilis screened for syphilising by using rapidplasma reagent test (RPR) and confirmed by TPHA forthose who were RPR positive. The women with pregnantsyphilispositive serology were systematically interviewedto obtain . During the interview, their demographicdetailsinformation,patterns of risk behaviors andother data. Data were collected andwere analyzedretrospectively.Results: Among Of 118,235 pregnant women surveyed,555 pregnant women were confirmed to have syphilis(prevalence of 4.69%), with a incidence of 4.69‰。 123women were excluded from the analysis because of in-complete medical records. Of 432 infected subjects withcomplete medical records, the average age was 26.8, witha range of 19 to 41. 7.41% (32/432) of them suffered fromprimary syphilis, 3.24% (14 /432) were ofhad secondary syphilis, and 89.35% (386/432) had latent syphilis. with-out any conspicuous clinical signs and symptoms.Conclusions: The prevalence of syphilis among the preg-nant women in our series was high and most of them wereasymptomatic. Screening for syphilis among pregnantwomen in Shenzhen is of importantce for the preventionof mother-to-child transmission of syphilis.

Anisakid Nematodes of Pagellus acarne and Trachurus trachurus, from North Atlantic Moroccan＇s Waters

An epidemiological survey of anisakid nematodes was conducted on 205 specimens of horse mackerel （Trachurus trachurus） and 183 of axillary seabream （Pagellus acarne） captured in the zone between Tangier and Larache in the north Atlantic Moroccan＇s coasts. Three species of nematodes were morphologically identified： Anisakis simplex s.l., Hysterothylacium sp., Pseudotarranova sp. According to the season, the nematode most observed in T. trachurus was .4. simplex s.1. （the highest values of prevalence （100%）, the mean intensity （48.6）. Hysterothylacium sp. was the most frequent anisakid in P. acarne with 100% of prevalence and 34.46 of the mean intensity. The infestation parameters were also analyzed according to the host species length, noting a maximum of infected fish by Anisakis simplex s.1. （96%） in samples of horse mackerel larger than 28 cm, while in axiliary seabream, the highest prevalence of infestation by Hysterothylacium sp. （100%） was found in fish more than 29 cm.

Epidemiological Investigation and Genetic Characterization of Type 2 PCV2 （Type 2 Porcine Circovirus） in Mexican Commercial Herds

PCV2 （Porcine circovirus type 2） is considered as the essential infectious agent of PMWS （post weaning multisystemic wasting syndrome） in pigs. Serological studies have shown that the virus is ubiquitous. Currently, there are many reports about the epidemiology and genetic characteristics of this virus around the world, but in Mexico it has not been studied. More than 3,500 samples of serum, rectal swabs, tissues and semen of 34 Mexican porcine farms from 10 important producer regions were analyzed by PCR. Results show that 97% of the farms were positive. Both genotypes, PCV2a and PCV2b were detected. It also found that the most prevalent genotype in Mexico is PCV2b. Regarding to amino acid sequence; three major heterogenic regions were present in the positions 59-91,123-136 and 185-210.