Even during the summer season, cold symptoms can arise. These can be caused by the enterovirus that brings sneezing, scratchy throat and runny noses into our homes. Less common enteroviruses can cause symptoms like conjunctivitis (aka pinkeye), which causes swelling of the outer layer of the eye and eyelid. Summer colds caused by enteroviruses can clear up without treatment in a few days or week. But do call your doctor if you present with a rash or high fever.