云南省2002-2004年乙型脑炎流行病学分析

目的了解云南省乙型脑炎流行特征,为制定乙型脑炎预防控制策略提供依据。方法对云南省2002-2004年乙型脑炎疫情资料统计分析,用ArcV iew G IS3.3制图。结果从图中发现,云南省的镇雄、隆阳、威信3县乙型脑炎发病数最高,其次为潞西市、广南县、景洪市、施甸县。结论利用地理信息系统制图能直观的反映云南省乙型脑炎流行现状。结果提示在该疾病高发地区应采取杀虫剂灭蚊喷洒、接种乙型脑炎疫苗等控制措施。     

云南省洱源县流行性乙型脑炎暴发流行的病原分离与鉴定

１９９１年７￣１０月,云南省洱源县发生流行性乙型脑炎暴发流行,采用滤过性试验,免疫荧光试验,交互ＨＩ试验,交互ＣＦ试验和中和试验方法,对从该县流行期采集的病人血清分离的２株病毒和从三带喙库蚁分离到的２株病毒进行鉴定,证实４株病毒均为流行性乙型脑炎病毒,从病原学证实为流行性乙型脑炎暴发流行,同时还查明了三带喙库蚊是本次乙型脑炎流行的主要传播媒介。     

食蚊鱼和双硫磷对三带喙库蚊的综合防制

三带喙库蚊是东南亚乙型脑炎和西尼罗病毒的重要传播媒介。印度许多地区曾发生乙型脑炎的暴发流行,从三带咏库蚊中已分离出乙型脑炎的病毒,证明是主要媒介。这种库蚊在德里     

我国乙型脑炎病毒优势基因型转换及其风险和对策

乙型脑炎是由乙型脑炎病毒引起的人畜共患病,在自然界中主要是通过蚊虫叮咬进行传播,能够引起人的中枢神经系统损伤和猪的繁殖障碍等疾病,对公共卫生安全造成了严重威胁。 由于乙型脑炎病毒在水禽宿主中的适应性差异,导致了病毒优势基因型由 GⅢ型逐渐向 GⅠ型转变。 乙型脑炎病毒优势基因型的转换和流行范围的扩大给疾病防控带来了新挑战,本文对我国乙型脑炎病毒优势基因型转换及其风险和对策进行了综述。     

编者的话

流行性乙型脑炎的发病季节快到了,本刊为了配合这种流行病的防治工作,这一期加大页码,以流行性乙型脑炎为重点。流行性乙型脑炎在我省的流行情况是较为严重的。历年来,由于中西医的配合,积极进行防治,收到了很大的成绩,降低了病死率,并获得了很多的治疗经验。这一期所选编的稿件,都是我省各地区医疗部门多年来防治乙型脑炎的经验总结,并在省卫生厅召集的流行性乙型脑炎防治会议上座谈过,大家一致认为这些经验是我省几年来防治流行性乙型脑炎比较完整的系统材料,其中尽管还有一些不够完善     

抗流行性乙型脑炎病毒药物的研究进展

流行性乙型脑炎(Japanese Encephalitis,JE)是由黄病毒科(Flaviridae)黄病毒属(Flavivirus)流行性乙型脑炎病毒(Japanese Encephalitis Virus,JEV)引起的,在自然界中主要以猪为宿主,经蚊传播的一种蚊媒性人兽共患传染病。该病主要流行于亚洲及西太平洋地区,严重威胁着人类健康,已成为人类脑炎疾病最主要的病因之一,并影响养猪业的发展,引起了世界性的广泛关注,因此,流行性乙型脑炎的防治研究有着重要的实际应用意义。到目前为止,尚无治疗流行性乙型脑炎特效药面市,但对抗流行性乙型脑炎病毒药物的研究已有一定的进展,而我国在这方面的系统介绍较少,本文就近10年来抗流行性乙型脑炎药物及其作用机制的研究进展做一综述,旨在为流行性乙型脑炎的预防和治疗提供参考。     

治疗流行性乙型脑炎及其后遗症的经验

流行性乙型脑炎是由滤过性病毒所引起的流行于夏、秋二季的一种急性传染病。古代的中医书中虽没有“乙型脑炎”这一病名的记载,但对于相似乙型脑炎的症状及治法,却散载在很多论治温病、疫病的书中,无疑问,西医所称之乙型脑炎应属于中医所说的温热病范畴的。温病的名称和理论很早见于内经和难经,在这两部书中还找不出相似乙型脑炎症状的记载,但在汉代张仲景的伤寒论中却有酷似乙型脑炎症状的记述,如辨太阳病脉证并治法上篇中云:“太阳病发热而渴不恶寒者为温病。”(按:所谓太阳病应有头项强痛的症状),又云:“若     

单味大青叶治疗流行性乙型脑炎23例疗效报告

流行性乙型脑炎的治疗,中医中药确有良好效果;但治疗方剂繁多,辨症論治不易掌握,則疗效各家报告均无一致。因此,关于流行性乙型脑炎治疗问题,有值得进一步探討的必要。現将我院以单味大青叶治疗流行性乙型脑炎23例疗效报告如下,供同道参考。 診断該組所有病例之診断,均根据发病季节,流行地区,临床典型症状和体征,血象以及符合流行性乙型脑炎的脑脊液改变而确立診断。该組所有病例均系自1954年7月下旬至9月中旬     

红古区健康人群流行性腮腺炎和乙型脑炎抗体水平监测分析

目的 了解2019年甘肃省兰州市红古区健康人群流行性腮腺炎和乙型脑炎血清IgG抗体水平,评价疫苗免疫效果和人群免疫状况,为制定免疫规划策略和防治措施提供依据.方法 采用分层随机抽样法,采集兰州市红古区362名健康人群静脉血,以酶联免疫吸附法(ELISA)检测流行性腮腺炎和乙型脑炎血清IgG抗体.结果 2019年监测红古区健康人群362人,流行性腮腺炎抗体阳性率为95.58％,不同年龄组抗体阳性率差异无统计学意义(x2=5.274,P＞0.05);乙型脑炎抗体阳性率为91.99％,5岁以下组较5岁以上组低,不同年龄组差异有统计学意义(x2=29.926,P＜0.05);不同性别人群流行性腮腺炎(x2=0.580)、乙型脑炎(x2=1.971)抗体阳性率差异无统计学意义(P＞0.05),不同地区人群流行性腮腺炎(x2=3.090)、乙型脑炎(x2=1.878)抗体阳性率差异亦无统计学意义(P＞0.05).结论 兰州市红古区健康人群流行性腮腺炎和乙型脑炎免疫状况良好,提高免疫规划疫苗接种率、加强查漏补种是控制疫苗相关疾病的重要措施.     

乙型脑炎疫苗研究进展

乙型脑炎(JE)是一种蚊传的乙脑病毒所致的感染性疾病，主要在亚洲流行，约10亿亚洲儿童受本病感染的威胁，发病率高达10／10万；每年报告的发病人数都在16，000以上。引起约5，000人死亡。由于漏报的广泛存在，实际发病人数高于此数。尽管随着防治工作的开展，特别是疫苗接种的推广，本病发病率有所下降(其中在日本、韩国、中国     

广东省乙型脑炎流行特征及其防制策略

目的分析广东省乙型脑炎流行特征,探讨防制策略。方法采用SPSS12.0软件建立数据库,进行描述性流行病学分析和多重线性回归分析。结果1990年以来,广东省于1995年和2003年出现2次乙脑发病的小高峰,其余各年度乙脑报告发病率均较低,疫情比较稳定。疫情主要分布在粤西和粤东地区;发病时间集中在每年5～7月,6月份为发病高峰;乙脑报告病例以1～14岁儿童为主,多为无免疫史和免疫史不详者。多重线性回归分析结果显示稻田种植面积、年平均降雨量与乙脑发病率存在统计学关联。结论广东省乙脑流行呈现明显的周期性、季节性和一定的地域性,1～14岁儿童为乙脑易感人群。接种乙脑疫苗和灭蚊是预防控制乙脑流行的重要措施。     

An ecological approach to preventing human infection: vaccinating wild mouse reservoirs intervenes in the Lyme disease cycle

Many pathogens, such as the agents of West Nile encephalitis and plague, are maintained in nature by animal reservoirs and transmitted to humans by arthropod vectors. Efforts to reduce disease incidence usually rely on vector control or immunization of humans. Lyme disease, for which no human vaccine is currently available, is a commonly reported vector-borne disease in North America and Europe. In a recently developed, ecological approach to disease prevention, we intervened in the natural cycle of the Lyme disease agent (Borrelia burgdorferi) by immunizing wild white-footed mice (Peromyscus leucopus), a reservoir host species, with either a recombinant antigen of the pathogen, outer surface protein A, or a negative control antigen in a repeated field experiment with paired experimental and control grids stratified by site. Outer surface protein A vaccination significantly reduced the prevalence of B. burgdorferi in nymphal blacklegged ticks (Ixodes scapularis) collected at the sites the following year in both experiments. The magnitude of the vaccine's effect at a given site correlated with the tick infection prevalence found on the control grid, which in turn correlated with mouse density. These data, as well as differences in the population structures of B. burgdorferi in sympatric ticks and mice, indicated that nonmouse hosts contributed more to infecting ticks than previously expected. Thus, where nonmouse hosts play a large role in infection dynamics, vaccination should be directed at additional species.     

Mechanistic insights into the impairment of memory B cells and antibody production in the elderly

It is well established that immunologic memory generated early in life can be maintained into old age and mediate robust anamnestic antibody responses. Little is known, however, about the initiation of memory B cells in the elderly. We have conducted a prospective analysis of the quantities and functionalities of antigen-specific B cell responses and its association with the functional helper CD4⁺T cell responses. The ability of naïve B cells from old (60–80 years) and young (20–31 years) humans to establish functional memory was examined following primary and booster vaccination with an inactivated-virus vaccine against tick-borne encephalitis. Our data show that the number of antigen-specific memory B cells generated during primary vaccination was ～3-fold lower in old than in young individuals. The maintenance and booster responsiveness of these memory B cells were not compromised, as evidenced by similar increases in specific memory B cell frequencies upon revaccination in old and young adults. In contrast, the Ab response mediated per memory B cell after revaccination was dramatically diminished in the elderly. Also, antigen-specific IL-2-positive CD4⁺T cell responses were strongly reduced in the elderly and displayed an excellent correlation with Ab titres. The data suggest that the dramatically lower antibody response in the elderly could only partially be accounted for by the reduced B cell numbers and was strongly correlated with profound functional defects in CD4 help.     

Seroprevalence of hepatitis A and cost evaluation of different vaccination strategies against hepatitis A virus in patients with chronic hepatitis C in France

OBJECTIVES: To prospectively determine the prevalence of total hepatitis virus A antibodies in patients with chronic hepatitis C and to evaluate the direct costs of several vaccination strategies against hepatitis A virus in these patients. METHODS: From April 1 to July the 31 1998, 219 patients with hepatitis C virus antibodies underwent a systematic testing for total hepatitis virus A antibodies (MEIA-AXSYM, Abbott laboratories). The prevalence of hepatitis A virus antibodies was evaluated according to age and suspected way of hepatitis C contamination. This prevalence has been compared to that in individuals undergoing a check-up provided by the national health insurance system stratified by age. Direct costs of 2 vaccination strategies "A" and "B" were evaluated according to age (<40 vs > 40 years) and number of vaccine doses (1 or 2). "A" strategy included the systematic vaccination of all patients without determining the presence of total hepatitis A antibodies. "B" strategy included testing for total hepatitis A antibodies and vaccination of seronegative patients. The costs of these two strategies (A and B) were calculated with one and two vaccine doses. RESULTS: The prevalence of total hepatitis A antibodies was 76% in the entire population. It increased after the age of 35 and was statistically higher in patients who were older than 40 than in patients younger than 40. This prevalence was not significantly different from that in individuals who underwent a check-up provided by the national health insurance system stratified according to age. "B" strategy with 2 vaccine doses was less expensive that A strategy in the whole population and in patients younger than 40. This strategy was less expensive with 1 vaccine dose except in patients who had recently screened positive for hepatitis C antibodies younger than 40 when it induced an increased in direct cost due to the low prevalence of total hepatitis A antibodies in these patients. CONCLUSIONS: In patients with hepatitis C antibodies with a high prevalence of total hepatitis A antibodies, testing for the prevalence of these antibodies before vaccination decreases the direct cost of this vaccination.     

Simultaneous vaccination in Japanese travelers

BACKGROUND: Simultaneous vaccination is not common in Japan because there is little information available on its effects. Some people are quite concerned about the possibility of adverse reactions due to simultaneous vaccination. The objective of this study was to evaluate whether the frequency and severity of adverse effects are increased by simultaneous vaccination in comparison to single vaccination. METHOD: A retrospective observational study was conducted in 399 asymptomatic travelers who visited the travel clinic during the period January-July 2005. One hundred forty-two participants were given a single vaccination, 257 participants were given simultaneous vaccination. Travel-specific vaccinations were for hepatitis A, hepatitis B, tetanus, rabies and Japanese encephalitis, and routine vaccines were for diphtheria+tetanus, measles, mumps and oral polio vaccine. To evaluate adverse effects, travelers were asked to complete a prepared questionnaire after vaccination. RESULTS: Adverse effects were reported by 26.3% of travelers, with 21.8% reporting local reactions and 4.5% reporting systemic reactions. The simultaneous vaccination group reported significantly more frequent adverse effects than those reported by the single vaccination group. Particularly, tetanus vaccination was shown to significantly raise the risk of adverse effects (P<0.001). However, no serious adverse effects were reported. CONCLUSIONS: Simultaneous vaccination was feasible for Japanese travelers because most problems were generally minor and related to local reactions at the sites of injections. Provision of a simultaneous vaccination schedule should motivate more Japanese travelers to obtain immunizations and thereby reduce the risk of vaccine-preventable diseases.     

Serological survey of viral hepatitis A, B, and C at Thai Central Region and Bangkok: a population base study

Hepatitis A, B, and C are important viral hepatitis infections in the Thai population. Hepatitis B vaccination was included in the Thai Expanded Program on Immunization (EPI) 10 years ago. In addition, the seroprevalence of hepatitis A has significantly changed in the last two decades. This study was done to evaluate current risk groups for hepatitis A and B infections and identify the magnitude of hepatitis C infection in the general population of Bangkok and six provinces in the Central Region of Thailand, during the period October 2000 to January 2002. This study revealed that the prevalence of anti-HAV in people younger than 25 years was low but very high in people older than 25 years. The prevalence of anti-HAV was 1.95% in Bangkok and 12.7% in other provinces in people younger than 25 years (p<0.001) while 90.9% in Bangkok and 88.2% in other provinces among people older than 25 years. Therefore, people who are older than 25 years should have a blood test for anti-HAV before getting a hepatitis A vaccination. Approximately 80% of people who are not covered by hepatitis B vaccination from EPI are at risk of hepatitis B infection and its complications. This group of people should receive hepatitis B vaccination. For hepatitis C, the prevalence is lower than 2% across age groups and areas. Therefore, current good primary prevention via blood donor screening and health education must be maintained.     

Chronic hepatitis B virus in the Philippines

Multiple studies have shown a high prevalence of chronic hepatitis B (CHB) infection in the Philippines, not only in high‐risk populations but also in the general population. The most recent national study estimated HBsAg seroprevalence to be 16.7%, corresponding to an estimated 7.3 million CHB adults. The factors underlying the high prevalence of CHB and its sequelae include the inadequate use of vaccination for prevention and the lack of treatment for many Filipinos. Because without medical monitoring and treatment of CHB the risk of progression to liver failure and death is 25–30%, the ultimate medical and societal costs will be very high if the Philippines fails to properly address hepatitis B infection. It will be very important to move forward with programs that can help to ensure universal vaccination of newborns, screening and vaccination nationwide, and monitoring and treatment for CHB persons. It will also be crucial to address transmission of HBV in the health‐care setting (via contaminated needles and syringes and inadequately sterilized hospital equipment) and via injection drug use and tattooing. Because of the relatively low average per capita income and the lack of coverage by PhilHealth of outpatient visits and medications, there is an urgent need to move forward with a nationally supported program that includes education for both the general public and health‐care workers on liver disease and screening for hepatitis viruses, followed by, as appropriate, vaccination or treatment, with expanded government coverage for these for all those who could not otherwise afford it.     

The effectiveness of the national hepatitis B vaccination program 25 years after its introduction in Iran: a historical cohort study

IntroductionHepatitis B virus (HBV) is responsible for one of the most common human viral infections. An estimated 257 million people are living with chronic HBV infection worldwide, and mortality has reached 900,000 deaths in recent years. In 2001, the World Health Organization reported a prevalence of chronic hepatitis B infection in Iran between 2–7%.ObjectiveTo assess the effect of the national HBV mass vaccination program after 25 years.MethodsA retrospective cohort study was conducted in vaccinated and unvaccinated people according to the year of birth. Blood samples were obtained from each enrolled person and data about demographic variables, and medical and vaccination history were collected using a standardized questionnaire. Persons were considered uninfected if they were negative for both HBsAg and anti-HBc. Also, Vaccine effectiveness was measured by calculating the risk of disease among vaccinated and unvaccinated persons and defining the percentage risk reduction of infection in the vaccinated group.ResultsA total of 2720 persons were interviewed. The rate of HBV breakthrough infection among the vaccinated group was significantly lower than in unvaccinated group. One hundred ninety-four cases with positive HBV markers of infection were identified. The risk ratio of HBV infection was 0.71, 95% CI: 0.54–0.94 (vaccinated/unvaccinated). The estimated vaccination effectiveness against Hepatitis B infection was 29% (95% CI: 6%–46%).ConclusionsIran has successfully combined hepatitis B vaccination into regular immunization programs. The WHO goal of reducing HBsAg prevalence to an equivalent of 1% by 2020 has been reached. With respect to vaccination effectiveness and low prevalence of the disease in the country, catch-up hepatitis B vaccination programs for adolescents can guarantee the immunity of the population.     

Twenty-year survey of the epidemiology of hepatitis B in Denmark: effect of immigration

Implementation of hepatitis B virus (HBV) vaccination is being considered in Denmark. Therefore, a 20 y survey on the epidemiology of HBV infection was performed. All notified cases of acute HBV infection in Denmark from 1982 to 2002 were reviewed retrospectively and all available data from 1970 to 2001 on the prevalence of hepatitis B surface antigen (HBsAg) in different groups of the Danish population were studied. The notified annual incidence of acute HBV infection has declined from more than 200 cases to fewer than 50 cases in 2001. In the indigenous population there has been a similar decline in prevalence of HBsAg carriers, from 0.15 to 0.03%, but owing to immigration of new HBsAg carriers from developing countries the overall number of carriers has not changed. The small effect of immigration on the incidence of acute HBV infections as well as the decreasing prevalence of HBsAg carriers among Danes should be taken into account when planning new vaccination strategies in Denmark.     

Low Prevalence of Vaccination or Documented Immunity to Hepatitis A and Hepatitis B Viruses Among Individuals with Chronic Liver Disease

BackgroundDespite national guidelines emphasizing the importance of vaccination or documenting immunity to hepatitis A virus and hepatitis B virus for patients with chronic liver disease, the success of adhering to these recommendations is suboptimal. We aim to evaluate the prevalence of vaccination or documented reactivity to hepatitis A antibody and hepatitis B surface antibody among US adults with chronic liver disease.MethodsUsing 2011-2018 National Health and Nutritional Examination Survey data, adults with nonalcoholic fatty liver disease, alcoholic liver disease, hepatitis B, and hepatitis C were evaluated to determine prevalence of vaccination (self-reported completion) and hepatitis A antibody reactivity or hepatitis B surface antibody reactivity.ResultsOverall prevalence of vaccination or hepatitis A antibody reactivity was lowest among individuals with nonalcoholic fatty liver disease (60.8%; 95% confidence interval [CI], 57.9-63.6) and alcoholic liver disease (61.8%; 95% CI, 59.0-64.6), and highest among individuals with hepatitis B (82.9%; 95% CI, 76.8-89.0). Prevalence of vaccination or hepatitis B surface antibody reactivity was much lower: 38.6% (95% CI, 35.7-41.4) in nonalcoholic fatty liver disease, 40.7% (95% CI, 34.4-47.0) in chronic hepatitis C virus, and 47.1% (95% CI, 44.3-49.9) in alcoholic liver disease.ConclusionAmong US adults with chronic liver disease, prevalence of vaccination or documented reactivity to hepatitis A antibody and hepatitis B surface antibody was alarmingly low. These observations are particularly concerning given that underlying chronic liver disease increases risks of severe liver injury and decompensation from acute hepatitis A or hepatitis B infections.