[Measures of the effect of vaccination in an outbreak of measles].
Vaccine efficacy, the effectiveness of a vaccination programme and the fraction of a population that would be necessary to vaccinate in order to prevent a measles outbreak are studied in a population having a vaccination programme. A dynamic model for acute, directly transmitted diseases was applied, based on the rate of transmission, namely, the probability that the infectious agent is transmitted from an infected to a susceptible person within a short space of time. We carried out a population-based study where we observed the final attack rates among vaccinated and unvaccinated people for a measles outbreak. In this population, the vaccination programme is responsible for a reduction of: 82.41% of all cases in the non-vaccinated sector; 98.45% of the average risk of disease among the vaccinated; and 97.29% of all cases among the population as a whole. Under these conditions there is the possibility of disease outbreaks arising, outbreaks which could be prevented if the percentage of the vaccinated population exceeded 95%.
Amela Heras
C
C
Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid.
Pachón del Amo
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I
Ibáñez Martí
C
C
D002648:Child; D004196:Disease Outbreaks / Q000517:prevention & control* / Q000706:statistics & numerical data; D004341:Drug Evaluation; D006801:Humans; D008457:Measles / Q000453:epidemiology / Q000517:prevention & control*; D008458:Measles Vaccine / Q000276:immunology*; D015397:Program Evaluation; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data
D008458:Measles Vaccine