>> reporter: this viral facebook video shows when 4-year-old evelyn lewis suddenly lost the ability to stand. >> try real hard. >> we really started to panic when we were rushing her to the hospital. >> reporter: doctors quickly diagnosed her with tick paralysis. now her unsettling ordeal has become an urgent warning as experts brace for one of the worst tick seasons on record. >> we're seeing more than we've ever seen before because of the mild winter we had and also because there are more hosts. there's a white-footed deer mouse that ticks really love to attach to, so more mice, more ticks. >> reporter: and more ticks means a potential surge in cases of lyme disease and other rare but deadly illnesses like the powassan virus. but there are ways to minimize your risk -- use bug repellent with at least 20% deet. make sure to spray your legs and feet. >> the ticks don't fly, they crawl. so you want to protect yourself from the ground up. >> reporter: and most importantly -- >> check yourself, check your kids, check your pets after