免疫对预防疾病的公共卫生重要性

免疫对预防疾病的公共卫生重要性 免疫对预防疾病的公共卫生重要性2010年04月24日11:17免疫对预防疾病的公共卫生重要性 卫生部世界卫生组织联合新闻发布会背景材料之三 免疫的益处 通过诱导免疫力来预防疾病的手段--疫苗，正在全球范围被广泛性、常规性的应用，这也是基于常识性的原则:即避免疾病发生胜于发生疾病后再去治疗，让人们避免痛苦、伤残和死亡。2002年免疫预防避免了大约200万人死亡，另外，免疫预防降低了传染病的发生，缓解卫生系统压力，使节约下来的经费可用于其他的卫生服务。 免疫预防是一种已经证实的可以控制甚至消灭疾病的工具。1967-1977年期间世界卫生组织通过开展强化免疫活动，消灭了天花的自然流行。自从1998年世界卫生组织及其合作伙伴在全球开展消灭脊髓灰质炎以来，脊灰的发病已经下降了99%，使约5百万人逃脱了瘫痪的疾患。在2000至2008年期间，全球麻疹死亡下降了78%。 常用的疫苗 目前，所有发展中国家都通过常规疫苗接种来预防麻疹、脊髓灰质炎、白喉、破伤风、百日咳和结核病。作为使用多年的这一的疫苗组合现在已经发生了新的变化，如增加了乙肝疫苗。在发达国家，一般提供更宽的保护范围，通常包括针对流感、肺炎的优势株、腮腺炎的疫苗(腮腺炎通常与麻疹和风疹疫苗联合)，免疫规划一般即针对婴儿和儿童，也会根据各国所关注的疾病针对青少年或成人。 全球免疫接种率 全球来讲，自1974年世界卫生组织开展扩大免疫规划以来，接种率已经显著提高。在2003年，全球百白破联合疫苗三针接种率从1980年的20%提高到 78%。即便如此，估计全世界在2002年仍有210万人死于这些广泛使用疫苗所 能预防的疾病，其中包括140万5岁以下儿童。 有效性和安全性 所有常规免疫使用的疫苗预防疾病都非常有效，虽然没有任何疫苗可达到 100%的保护率。为增加产生免疫力的机会，一般会提供一剂次以上的疫苗接种。 疫苗是非常安全的，副作用轻微--特别是与其所预防的疾病相比较而言。发生 严重的并发症很罕见，例如，麻疹疫苗发生急性严重的过敏反应低于每百万剂 次1例。 免疫预防的成本效益 免疫被认为是最具成本效益的卫生干预措施。最近的研究表明，2002年肯 尼亚开展的为其一周的麻疹疫苗强化免疫活动，接种了1280万名儿童，其结果 是在未来的10年将节省1200万美元的卫生费用，并将预防385万麻疹病例和 避免12.5万人因麻疹死亡。Immunization against diseases of public health importanceThe benefits of immunization Vaccines-which protect against disease by inducing immunity-are widely and routinely administered around the world based on the common-sense principle that it is better to keep people from falling ill than to treat them once they are ill.Suffering,disability,and death are avoided.Immunization averted about two million deaths in 2002.In addition,contagion is reduced,strain on health-care systems is eased,and money is frequently saved that can be used for other health services. Immunization is aproven tool for controlling and even eradicating disease.An immunization campaign carried out by the World Health Organization(WHO)from 1967 to 1977 eradicated the natural occurrence of smallpox.Since the launch by WHO and its partners of the Global Polio Eradication Initiative in 1988,polio infections have fallen by 99%,and some five million people have escaped paralysis.Between 2000 and 2008,measles deaths dropped worldwide by 78%. Commonly used vaccines Routine vaccination is now provided in all developing countries against measles,polio,diphtheria,tetanus,pertussis,and tuberculosis.To this basic package of vaccines,which served as the standard for years,have come new additions,such as hepatitis Bvaccine.In industrialized countries awider span of protection is typically provided,often including vaccines against influenza,predominant strains of pneumococcal disease,and mumps(usually in combination with measles and rubella vaccine).Immunization programmes may be aimed at adolescents or adults-depending on the disease concerned-and at infants and children. Global immunization coverage Globally,coverage has greatly increased since WHO's Expanded Programme on Immunization began in 1974.In 2003,global DTP3(three doses of the diphtheria-tetanus-pertussis combination vaccine)coverage was 78%-up from 20%in 1980.However,an estimated 2.1 million people around the world,including 1.4 million childre nunder age five,still died in 2002 of diseases preventable by widely used vaccines. Effectiveness and safety All vaccines used for routine immunization are very effective in preventing disease,although no vaccine attains 100%effectiveness.More than one dose of avaccine is generally given to increase the chance of developing immunity.Vaccines are very safe,and side effects are minor? especially when compared to the diseases they are designed to prevent.Serious complications occur rarely.For example,an immediate severe allergic reaction to measles vaccine(anaphylaxis)occurs in less than one case per million doses given. The cost-effectiveness of immunization Immunization is considered to be among the most cost-effective of health investments.A recent study estimated that aone-week"supplemental immunization activity"against measles carried out in Kenya in 2002?in which 12.8 million children were vaccinated-would result in anet saving in health costs of US million over the following ten years;during that time it would prevent 3850 000 cases of measles and 125 000 deaths. (来源:卫生部网站)(lxy)