According to the Centers for Disease Control and Prevention (CDC), approximately thirty thousand cases of Lyme disease are reported by state health departments every year. This number, however, does not reflect every case of Lyme disease in the US. More recent estimates believe that number may be closer to three hundred thousand .
Lyme disease cases in the United States have tripled over the last twenty years. Today, it is the most commonly reported vector-borne disease in the Northern Hemisphere. The reason for this is because tick populations have increased dramatically. In the last two decades, they have doubled their established range .
Of course, finding an effective treatment for Lyme Disease is of paramount importance. What is perhaps just as important is figuring out how we can prevent it in the first place. One way to do this, of course, is to control the tick population.
But how can we keep the number of ticks at a manageable level? There may be an unlikely hero in the battle against Lyme Disease: opossums. Not only do these humble animals help control tick populations, but there are also many other opossum benefits. While the exact degree they have on the spread of the disease has not been determined, it’s safe to say they’re (at the very least) lending a helping hand.
The Opossum- The Tick Slayer?
In March 2016, an image of an opossum began circulating on the internet with the following text:
“While many woodland creatures harbor ticks and spread Lyme disease, opossums kill 96.5% of ticks that land on them and a single opossum may be “hoovering up and killing” 4000 ticks every week and thereby protecting us from Lyme disease” .
But is this true? As this photo gained more traction, many people began to express skepticism. It seemed too good to be true that one animal could single-handedly save us from Lyme disease.
In 2014, the Cary Institute of Ecosystems Studies and NewsTimes published an article outlining the role opossums play in tick control. Researchers tested the following six species:
- White-footed mice
They then exposed each species to one hundred ticks. Of the six, they found that opossums were remarkably good at getting rid of ticks. Opossums groom themselves frequently and thoroughly. If they find a tick, they lick it off and swallow it.
The team determined that in one season, a single opossum kills approximately five thousand ticks. So while the text in the photo got the numbers wrong, the idea that an opossum kills ticks is true 
These findings were consistent with another study from 2009. This study also found that opossums kill eighty to ninety percent of the ticks that attempt to feed on them. This study pointed out that a loss of biodiversity (ie- removing certain animals from an environment) can cause an increase in insects like ticks, which are vectors for human disease .
Read: Asian Lady Beetles: Where They Came From and How to Get Rid of Them
Three Other Opossum Benefits
Opossums do more than just kill ticks. It turns out America’s only marsupial is quite a helpful little creature:
1. They Take Care of Unwanted Pests
Opossums eat more than just ticks. They also frequently eat cockroaches, rats and mice. This is helpful to us because those creatures can be carriers of disease .
2. They Help Keep Your Garden Healthy
Opossums also like to eat snails and slugs, which can damage your plants and garden. They will also often eat overripe fruits or berries that have fallen to the ground, which keeps your garden nice and clean .
3. They Reduce the Snake Population
Opossums are resistant to snake venom, and so they can eat them, too. In some areas, like in Illinois, opossums prey on southern and northern copperheads and the timber rattlesnake. This can help to control the snake population, making you less likely to have a run-in with one .