New field testing shows Guardian, a spatial repellent made by SC Johnson, is demonstrating what the privately-held company is calling “game-changing efficacy of one year.” Spatial repellents are easy-to-use products that can be hung in semi-enclosed spaces (including homes, schools and humanitarian settings) to repel mosquitoes. “Guardian’s efficacy rate of one year is a game-changer because it covers multiple rainy seasons, when people are at higher risk for mosquito-borne disease,” said ...