Altes Hester Korthals, Dijkstra Frederika, Lugnèr Anna, Cobelens Frank, Wallinga Jacco
Department of Infectious Diseases Epidemiology, National Institute for Public Health and the Environment, Bilthoven, The Netherlands.
Epidemiology. 2009 Jul;20(4):562-8. doi: 10.1097/EDE.0b013e31819e3c1a.
BCG vaccine protects against the severe forms of tuberculosis (TB) in children. Several low-prevalence countries are reviewing their policy, usually shifting from universal vaccination to vaccination of infants in high-risk groups only. We combined an epidemiologic analysis with a cost-effectiveness analysis to evaluate the cost-effectiveness of targeted strategies.
We fitted a static model to the data to estimate vaccine efficacy and risk of disease. We applied our method to the Dutch situation, analyzing severe TB cases in high-risk group children age 0-5, between 1996 and 2003. We considered the current strategy targeting immigrant children from high-incidence countries, and a proposed strategy additionally targeting children from 3 lower-incidence, but higher-immigration, countries.
In the absence of vaccination, the annual risk of developing severe TB for a child in the current target group is 3/100,000, while BCG vaccination reduces this risk by 73%. Therefore about 9000 children would need to be vaccinated to prevent 1 case. Vaccinating children from high-incidence countries would then cost about Euro 4,500 per discounted disability-adjusted life year averted. In the extended target group, the risk of disease is somewhat lower with a similar vaccine effectiveness, so costs are raised.
The current Dutch BCG strategy, as well as the proposed inclusion of immigrant children from Turkey, Surinam and former Yugoslavia, is on average cost-effective. However, the low number of both vaccinated and unvaccinated severe TB cases leads to broad confidence intervals on vaccine efficacy, highlighting the difficulty associated with decision-making in low-prevalence settings.
卡介苗可预防儿童严重形式的结核病（TB）。一些低发病率国家正在审查其政策，通常从普遍接种转向仅对高危组婴儿进行接种。我们将流行病学分析与成本效益分析相结合，以评估针对性策略的成本效益。
我们对数据拟合了一个静态模型，以估计疫苗效力和疾病风险。我们将我们的方法应用于荷兰的情况，分析了1996年至2003年间0至5岁高危组儿童中的严重结核病病例。我们考虑了当前针对来自高发病率国家的移民儿童的策略，以及一项提议的策略，该策略还针对来自3个低发病率但移民率较高的国家的儿童。
在不接种疫苗的情况下，当前目标组中儿童患严重结核病的年度风险为十万分之三，而卡介苗接种可将此风险降低73%。因此，大约需要为9000名儿童接种疫苗才能预防1例病例。为来自高发病率国家的儿童接种疫苗，每避免一个经贴现的伤残调整生命年的成本约为4500欧元。在扩大的目标组中，疾病风险略低，疫苗效力相似，因此成本有所增加。
荷兰目前的卡介苗策略以及提议纳入来自土耳其、苏里南和前南斯拉夫的移民儿童，平均而言具有成本效益。然而，接种疫苗和未接种疫苗的严重结核病病例数量都很少，导致疫苗效力的置信区间很宽，凸显了在低发病率环境中决策的困难。
