Broutin Hélène, Mantilla-Beniers Natalia B, Simondon François, Aaby Peter, Grenfell Bryan T, Guégan Jean-François, Rohani Pejman
UR 024, Institut de Recherche pour le Développement (IRD), 911, Avenue Agropolis BP 64501, 34394 Montpellier cedex 5, France.
Microbes Infect. 2005 Apr;7(4):593-9. doi: 10.1016/j.micinf.2004.12.018. Epub 2005 Mar 16.
Measles and pertussis are ubiquitous vaccine-preventable diseases, which remain an important public health problem in developing countries. Hence, developing a deep understanding of their transmission dynamics remains imperative. To achieve this, we compared the impact of vaccination at both individual and population levels in a Senegalese rural community. This study represents the first such comparative study in tropical conditions and constitutes a point of comparison with other studies of disease dynamics in developed countries. Changes in the transmission rates of infections are reflected in their mean ages at infection and basic reproductive ratio calculated before and after vaccination. We explored persistence of both infections in relation to population size in each village and found the inter-epidemic period for the whole area using wavelets analysis. As predicted by epidemiological theory, we observed an increase in the mean age at infection and a decrease in the reproductive ratio of both diseases. We showed for both the pre- vaccination and vaccine eras that persistence depends on population size. After vaccination, persistence decreased and the inter-epidemic period increased. The observed changes suggest that vaccination against measles and pertussis induced a drop in their transmission. Similarities in disease dynamics to those of temperate regions such as England and Wales were also observed.
麻疹和百日咳是普遍存在的可通过疫苗预防的疾病，在发展中国家仍然是一个重要的公共卫生问题。因此，深入了解它们的传播动态仍然至关重要。为了实现这一目标，我们在塞内加尔的一个农村社区比较了个体和群体层面的疫苗接种影响。这项研究是热带条件下的首个此类比较研究，与发达国家其他疾病动态研究形成了对比点。感染传播率的变化反映在接种疫苗前后计算出的平均感染年龄和基本繁殖率上。我们探讨了每个村庄两种感染与人口规模的持续关系，并使用小波分析找到了整个地区的流行间期。正如流行病学理论所预测的，我们观察到两种疾病的平均感染年龄增加，繁殖率下降。我们表明，在疫苗接种前和疫苗时代，持续性都取决于人口规模。接种疫苗后，持续性降低，流行间期增加。观察到的变化表明，麻疹和百日咳疫苗接种导致了它们传播率的下降。还观察到与英国和威尔士等温带地区疾病动态的相似之处。
