Be careful before diving inUpdated 11:44 AM ET, Tue June 28, 2016 Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds. Photos: Be careful before diving inSummer can be a time for bacteria and other microbes to flourish, from pools to picnics.Hide Caption 1 of 7 Photos: Be careful before diving inIngredients of potato salad such as potatoes, pasta and eggs -- not mayonnaise -- are prone to contamination. Hide Caption 2 of 7 Photos: Be careful before diving inListeria bacteria like to live in cooler temperatures and populate machinery, such as ice cream dispensers. Hide Caption 3 of 7 Photos: Be careful before diving inIn the most severe cases of sunburn, people can develop blisters and need to be treated like burn victims.Hide Caption 4 of 7 Photos: Be careful before diving inUrine is not an antidote to the venom of a jellyfish. Rinsing the wound with saltwater or using vinegar can be effective.Hide Caption 5 of 7 Photos: Be careful before diving inMold and bacteria love to grow on air conditioning filters, especially in the summer humidity. Hide Caption 6 of 7 Photos: Be careful before diving inSea lice, also known as seabather's eruption, can cause an itchy rash.Hide Caption 7 of 7Get out and enjoy the summer months. But be careful of some dangers that await you at the picnic, pool or beach.More from HealthObamacare's 'essential benefits' explainedTeen's death shows horror of flu epidemicDental coverage may be yanked under GOP health care planThe truth about 'gaydar'Are vegetable oils healthy?