Inapparent dengue in a community living among dengue-positive Aedes mosquitoes and in a hospital in Klang Valley, Malaysia

•Most people living in dengue hotspots are exposed to dengue without their knowledge.•Inapparent dengue is already widespread when dengue-positive Aedes mosquitoes are detected.•People living with dengue patients are likely to have been exposed to dengue without their knowledge.•Current diagnostic tools have limited ability to detect inapparent dengue.•Early and proactive dengue surveillance and control are needed, taking into account of asymptomatic transmission.