Tick season is in full swing, and by many counts there’s more to worry about this year than in past years.

The list of diseases that these vermin can carry has grown in recent years; the range across which they can thrive has also expanded. And according to at least some experts, this season will be a particularly bad one. 

The threat has trapped homeowners between two worries: tick-borne diseases on the one hand and potentially dangerous pesticides on the other. Do you spray your yard and expose your family to potentially dangerous chemicals? Or take your chances with diseases like Lyme that can cause lifelong debilitation? 

The good news is that you may not have to choose. Bait boxes, developed by the Centers for Disease Control and Prevention and available through licensed pest-control professionals, might enable you to fight ticks without spraying. 

What, Exactly, Are Bait Boxes?

Bait boxes are 5x7-inch boxes designed to attract the mice (and to a lesser extent chipmunks and voles) that are most responsible for spreading Lyme and other tick-borne pathogens. They contain two key ingredients: an insecticide that kills ticks and bait that attracts mice. As a rodent moves through the box, a wick containing a low-dose insecticide brushes its backside. Ticks that attach to the animal die after exposure to the insecticide. The rodents themselves are unharmed.

The boxes are installed (usually at the interface between a landscaped yard and wooded areas) and replaced at two specific intervals timed to disrupt the ticks’ life cycle at crucial stages across the season. In May the boxes kill off nymphs, young poppy-seed-sized ticks that seek blood meals from mice, household pets, and humans. In late July and early August, they kill larvae, newly-hatched tick offspring about the size of the period at the end of this sentence. Larvae are known to latch onto mice in droves (one mouse can carry 300 to 400 tick larvae), seeking both food and shelter. 

How Well Do They Work?

A study published in March in the Journal of Medical Entomology suggests that bait boxes can significantly reduced the prevalence of ticks on residential properties. After four nine-week deployments (two each conducted in 2012 and 2013) tick abundance was reduced by 97 percent on treated properties.

The researchers did note that bait boxes take longer than other management methods (like spraying) to make a dent in tick populations because they focus on the nymph and larval stages as opposed to egg-laying adults. They also conceded that more research is needed before anyone can say for certain how many boxes you need or what their overall effect is on the prevalence of Lyme and other diseases. 

Are They Safe?

The experts we spoke with believe the boxes are very safe, especially compared with some of the alternatives. “It’s an environmentally friendly approach to controlling ticks and reducing the risk of disease,” says CDC biologist Marc Dolan. “And you’re not applying pesticides to the environment.”

The insecticide used in bait boxes, Fipronil, is the same chemical used in tick-control products sold for cats and dogs (such as Frontline Top Spot, for example). But the bait boxes use a much lower dose, so your household pets should be safe, even if they happen to attack (or eat!) a critter that came into contact with the box.

The boxes are unlikely to attract additional pests, according to research done by Dolan and others. “We never saw a rodent population increase,” he says. “If anything, it goes down.”

Also important: The CDC says the boxes are child-resistant, meaning rodents and other critters can enter but your child’s hands and fingers cannot. 

Should You Use Them in Your Yard?

Consumer Reports’ experts believe they are a good option, especially if you’re particularly concerned about spraying pesticides. The main caveat may be price.

One box costs roughly $50 to install, and according to Dolan, the average home needs between five and 15 of them. You’ll also need two installations across the season, so for a yard that needs eight boxes, the annual cost for one year would be about $800. 

If that figure makes your eyes pop, do some comparative shopping, and consider our other tips for tickproofing your yard without spraying.