Can a Christmas Tree Give You Lyme Disease?

Claim
Some Christmas trees have dormant ticks and tick eggs that will hatch in your home. Those ticks can carry Lyme disease, threatening your family and pets.

Origin
This issue has gotten a lot of attention lately due to a recent meme that went viral. The photo was shared hundreds of times across Facebook and Pinterest, cautioning those in the holiday spirit that there’s a chance you’re bringing Lyme disease into your living room.

“Please be careful and wary of people giving ideas and suggestions on how to get rid of ticks off of Christmas trees,” the post says. “Shaking doesn’t work, watering them down doesn’t work. Be careful and know you are taking chances and risks here. What are the odds? Who knows. Ticks hide and crawl fast. A nymph tick is the size of a dot. If one female tick lays eggs under the bark of a tree, that tree will be infested with over 2,000 eggs. Which then hatch. Keep that in mind. ALL TICKS CAN CARRY AND TRANSMIT DISEASE.”

Commenters thanked those who distributed the info, saying they would be switching to artificial trees or placing a tick collar at the base of their real one.

Facts
Lyme disease is largely a seasonal issue, with winter being the least likely time to encounter infected ticks. December rarely sees confirmed cases of the disease, accounting for less than 2% of all reported cases based on 10 years of data. Lyme disease is so rare during this period because the majority of ticks are dormant.

Only nymphs and adult females can transmit Lyme disease to humans. Nymphs feed from May through July, which is why late spring to early summer is when Lyme disease cases peak. In the fall, the nymphs become adults. At this time, the females will attach themselves to a large mammal, mate, and die. By the time winter rolls around, almost all disease-carrying ticks are gone.

Both Christmas trees and Lyme disease are found across North America. However, Lyme disease has a more limited distribution, with 95% of cases coming out of just 14 states. Most of the states where the disease is prevalent are in the Northeast or Great Lakes regions. The top Christmas tree producer is Oregon, which hardly has any Lyme disease issues.

Even if you live in a Lyme disease hotspot, finding a nest of tick eggs on your Christmas tree is very unlikely. Blacklegged ticks lay eggs on the ground in May which hatch by summer.

Furthermore, even if your tree comes covered in tick eggs, they aren’t a hazard. Ticks aren’t born with Lyme disease, but instead get it by feeding on a disease-carrying bird or mammal. Simply put, tick larvae are pathogen free.

That doesn’t mean your tree can’t come with some other creepy crawlies, though.

“You need to just rest assured that these things are not ticks,” said Dr. Tom Mather, professor from the Department of Plant Sciences and Entomology at the University of Rhode Island.

Instead, the little black specks that might inspire fear are Cinara aphids, or Christmas tree aphids. These pests can be annoying, but they’re harmless. If you do bring in an infestation, it’s recommended that you don’t squash them because their sap diet produces purple gut contents that can stain carpet and furniture.

“Just vacuum them up,” Dr. Mather said.

Takeaway
Lyme disease is a serious concern for sportsmen, but the idea of getting sick from your Christmas tree is absurd. The odds of that happening are about equal to Santa bringing you the deed to 10,000 acres of riverbottom in Montana.

Sources
Lyme Disease Charts and Figures — CDC
Lifecycle of Blacklegged Ticks — CDC
Lyme Disease Maps — CDC
Cinara Aphids on Christmas Trees — North Carolina State
Interview with Dr. Mather

Feature image via WV Tourism.