Tick watchers – from foresters in upstate Pennsylvania to disease ecologists – report a population explosion among black-legged ticks, formerly known as deer ticks, this year. The cause isn't clear.

Some credit the mild winter, others say tick numbers have simply been on the uptick for years, while yet another theory credits the acorn boom of 2010. More acorns fed a baby boomlet among white-footed mice, the tick's preferred host. But when acorn and mouse numbers fell in 2011, extra ticks remained. Hungry ticks.

Pediatrician Barbara Gold, M.D., of St. Chris Care at Northeast Pediatrics in Philadelphia, hears about ticks over the phone, as anxious parents call with reports of these creepy-crawly insects on their kids. "The first thing people want to know is how to get a tick off," Gold says. "The second is, should they worry about Lyme disease." Gold shared her tick savvy with the Healthy Kids blog.

"The last thing parents should do is keep kids indoors due to fears about ticks," she notes. "The truth is that very few carry Lyme disease. And early signs of Lyme disease – when it's completely treatable with two weeks of antibiotics – are usually very easy to spot." Here's what you need to know:

#1: If your kid or teen's got a tick attached to his or her skin, pull it off with tweezers. "Those old wives' tales about covering it with petroleum jelly don't work," Gold says. "Grab the tick firmly with the tweezers and slowly pull it out." Grab the tick where it's attacked to the skin. You should see all of the tick come out, including mouth parts embedded in the skin. A tick has to be attached for at least 24 hours in order to pass Lyme disease along – getting it off early could stop transmission. So check kids daily – and check them all over. In one study, black-legged ticks showed no preference for special hiding places on the body. They showed up in equal numbers on arms, ears, feet, head, waist, groin, etc.

#2: Size up the tick: Is it more like a raisin or a sesame seed? Big ticks are usually dog ticks, which don't carry Lyme disease but can carry other diseases like Rocky Mountain spotted fever and tularemia. Black-legged ticks are small – from the size of the period at the end of this sentence to about the size of a sesame seed. They can carry Lyme disease as well as anaplasmosis and babesiois. "You don't have to keep the tick, but you should know how big it was in case your child develops symptoms," Gold says.

#3: Don't panic – do watch for symptoms. "If your child has no signs of Lyme disease, there's no need for treatment," Gold says. About 70 percent of people who develop Lyme get that famous bull's eye rash around the bite within two to four weeks. "It's a band of red skin around the bite that gets larger, while the center becomes clear," she says. "If you see that, call your doctor." Another symptom of early Lyme's disease: A swollen, painful joint – often a knee. "If your child starts complaining that a joint hurts and they didn't injure it, it could be Lyme disease," Gold says. "Some kids just feel like they have the flu. I believe in trusting a parent's instincts. If your child's just not feeling right and you can't explain it, it's worth talking with your doctor."

#4: Put barriers between kids and ticks. Long pants tucked into socks for hikes in the woods (light colors make ticks easier to spot) and bug repellents are good strategies, she says. "DEET in concentrations recommended for kids is effective and safe, if used as directed, in kids over the age of two," Gold notes. Don't over-use it and don't put it on little kids' hands, which can get it into their eyes or mouths. Skip combination sunscreen/repellent products – you'll want to reapply sunscreen frequently but don't have to reapply the repellent." Another option if your family's headed into the great outdoors: Repellent designed to spray on clothing, such as those containing the ingredient permethrin.

"Most herbal, organic repellents aren't as effective," Gold says.  But "natural" products containing the "biorepellents" picaridin (sometimes listed as KBR 3023 on labels) and IR3535 may help repel ticks.   Use vet-recommended tick repellents on dogs and cats, too, to keep ticks out of the house.