Sutherland I, Fayers P M
Br Med J. 1971 Mar 27;1(5751):698-702. doi: 10.1136/bmj.1.5751.698.
A study of the effect of measles vaccination on the incidence of the disease in eight separate areas of England and Wales was begun in 1966. It showed an inverse association between the proportion of children vaccinated and the incidence of measles in the area in the following year, but measles epidemics occurred in several of the areas in subsequent years, despite continuing vaccinations.Measles vaccination was introduced on a large scale in Britain in 1968. Analysis of the notification and vaccination statistics shows that the vaccination of about 10% of the child population (under 15 years) in 1968 sufficed to "replace" the measles epidemic which had been expected in the period October 1968 to September 1969 by a low incidence of the disease, typical of that in previous "interepidemic" years. Further, the effect of the vaccinations was to prevent the development of natural measles in susceptible unvaccinated children as well as in the vaccinated subjects. Thus the number of immune subjects in the community was increased by the vaccinations, but as a result there was a reduction in the number of subjects who acquired immunity from natural measles. These opposed results can therefore explain why vaccination may be effective in the community for only a year or two, though vaccination protects the individual for much longer.It is estimated that a continuing vaccination rate of 40 to 50% of the children born each year would be necessary to replace the regular biennial measles epidemics in Britain by a continuous endemic incidence, and might perhaps lead to the disappearance of the disease without a further major epidemic, but that a continuing vaccination rate of 80 to 90% of children born each year would then be necessary to prevent its reintroduction. The long-term control of measles by vaccination will thus probably prove more difficult than for any other infectious disease.
1966年，在英格兰和威尔士的八个不同地区开展了一项关于麻疹疫苗接种对该疾病发病率影响的研究。研究表明，接种疫苗的儿童比例与次年该地区的麻疹发病率呈负相关，但尽管持续进行疫苗接种，随后几年仍有几个地区发生了麻疹疫情。1968年，麻疹疫苗在英国大规模推广。对疫情通报和疫苗接种统计数据的分析表明，1968年约10%的儿童人口（15岁以下）接种疫苗足以使1968年10月至1969年9月期间原本预计会发生的麻疹疫情被低发病率所“取代”，这种低发病率是此前“疫情间期”年份的典型特征。此外，疫苗接种的作用是防止易感的未接种儿童以及已接种儿童感染自然麻疹。因此，疫苗接种增加了社区中免疫人群的数量，但结果是通过自然麻疹获得免疫力的人群数量减少了。所以，这些相反的结果可以解释为什么疫苗接种在社区中可能仅在一两年内有效，尽管疫苗接种对个体的保护时间要长得多。据估计，要通过持续的地方流行发病率来取代英国常规的两年一次的麻疹疫情，每年需要有40%至50%的新生儿持续接种疫苗，这或许可能导致该疾病在没有进一步大流行的情况下消失，但之后每年需要有80%至90%的新生儿持续接种疫苗才能防止其再次出现。因此，通过疫苗接种对麻疹进行长期控制可能比控制其他任何传染病都更困难。
