Estimation of the direct and indirect effects of vaccination.
Indirect effects play a major role in the protection afforded by a vaccination programme. In this work we define new measures of direct, indirect and total (direct + indirect) effects of a vaccination programme in terms of the protection they provide to unvaccinated and vaccinated individuals, and to the entire population. We show how these measures can be estimated using data from a vaccine trial or an observational study. The bias and standard errors of these estimates can be evaluated via stochastic simulations. Examples from a mumps outbreak and a (hypothetical) HIV vaccine trial are used to illustrate the estimation of these new measures of vaccination effectiveness.
Haber
M
M
Department of Biostatistics, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA. mhaber@sph.emory.edu
D016915:AIDS Vaccines / Q000008:administration & dosage; D015982:Bias; D002648:Child; D004196:Disease Outbreaks / Q000517:prevention & control; D005260:Female; D015658:HIV Infections / Q000517:prevention & control / Q000635:transmission; D006801:Humans; D008297:Male; D015233:Models, Statistical; D009107:Mumps / Q000517:prevention & control; D009108:Mumps Vaccine / Q000008:administration & dosage; D011336:Probability; D011897:Random Allocation; D013269:Stochastic Processes; D014611:Vaccination
D016915:AIDS Vaccines; D009108:Mumps Vaccine