learning about the cause of something has a positive impact on preventing that something & learning about the cause of a disease has a positive impact on finding a cure for the disease ->  learning about the cause of a disease has a positive impact on preventing / finding a cure for that disease  learning about the cause of a disease has a positive impact on preventing / finding a cure for that disease & research is used for learning ->  research on a disease has a positive impact on preventing / finding a cure for the disease  research on a disease has a positive impact on preventing / finding a cure for the disease & if something has a positive impact on a process then that something helps that process ->  research on a disease helps prevent / find a cure for that disease  society is made of humans & disease has a negative impact on an organism ->  disease has a negative impact on society  disease has a negative impact on society & decreasing something negative has a positive impact on a thing ->  decreasing disease has a positive impact on society  preventing something decreases the amount of that something & curing something can mean decreasing the amount of that something ->  preventing / curing something can decrease the amount of that something  decreasing disease has a positive impact on society & preventing / curing something can decrease the amount of that something ->  preventing / curing disease has a positive impact on society  research on a disease helps prevent / find a cure for that disease & preventing / curing disease has a positive impact on society -> research on a disease has a positive impact on society by helping to prevent / cure that disease