We identified three primary mechanisms of spillovers : reduced disease transmission , social proximity and substitution of re sources within households .
We found the strongest evidence for spillovers through reduced disease transmission , particularly vaccines and mass drug administration .
In general , the proportion of a population receiving an intervention was associated with improved health .
We found evidence of publication bias for certain spillover estimates but not for total or direct effects .
Conclusions We found the strongest evidence for spillovers from vaccines and mass drug administration to control infectious disease .
There was little high quality evidence of spillovers for other interventions
Background Many interventions delivered to improve health may benefit not only direct recipients but also people in close physical or social proximity .
Our objective was to review all published literature about the spillover effects of interventions on health outcomes in low-middle income countries and to identify methods used in estimating these effects .
The Minicommunity Design to Assess Indirect Effects of Vaccination
Abstract We propose the minicommunity design to estimate indirect effects of vaccination . Establishing indirect effects of vaccination in unvaccinated sub population s could have important implication s for global vaccine policies . In the minicommunity design , the household or other small transmission unit serves as the cluster in which to estimate indirect effects of vaccination , similar to studies in larger communities to estimate indirect , total , and overall effects . Examples from the literature include studies in small transmission units to estimate indirect effects of pertussis , pneumococcal , influenza , and cholera vaccines . We characterize the minicommunity design by several method ologic considerations , including the assignment mechanism , ascertainment , the role of transmission outside the transmission unit , and the relation of the size of the transmission unit to number of people vaccinated . The minicommunity study for indirect effects is contrasted with studies to estimate vaccine effects on infectiousness and protective effects under conditions of household exposure within small transmission units . The minicommunity design can be easily implemented in individually r and omized studies by enrolling and following-up members of households of the r and omized individuals . The methodology for the minicommunity design for estimating indirect effects of vaccination deserves much future research
We identified three primary mechanisms of spillovers : reduced disease transmission , social proximity and substitution of re sources within households .
We found the strongest evidence for spillovers through reduced disease transmission , particularly vaccines and mass drug administration .
In general , the proportion of a population receiving an intervention was associated with improved health .
We found evidence of publication bias for certain spillover estimates but not for total or direct effects .
Conclusions We found the strongest evidence for spillovers from vaccines and mass drug administration to control infectious disease .
There was little high quality evidence of spillovers for other interventions
Background Many interventions delivered to improve health may benefit not only direct recipients but also people in close physical or social proximity .
Our objective was to review all published literature about the spillover effects of interventions on health outcomes in low-middle income countries and to identify methods used in estimating these effects .