Opossums might be some of the weirdest looking animals to grace our streets in areas of urban sprawl but these critters may be one of the best defences we have against Lyme disease. According to research by ecologists and environmentalists opossums, which are America’s only pouched marsupials, meticulously groom themselves and, in the process, consume and destroy the ticks that carry Borrelia burgdorferi.
This southern species of mammal has gradually made its way north through a process of adaptation and helped by climate change, just as ticks have gradually spread north. Opossums have been around since the age of the dinosaurs and are known for snuffling out tasty morsels wherever they go, eating grubs and insects, and even mice when they get the chance.
Playing Possum – Not When it Comes to Lyme Disease
Now it seems that they also attract the black-legged ticks that carry Lyme disease bacteria, but rather than acting as a serious host reservoir for the infectious disease, they actually work as net killers of Lyme bacteria by picking the ticks off their fur and eating them. These animals, known for drooling, snarling, and hissing before playing dead, do not, it appears, play possum when it comes to tick bites.
Opossums – Efficient Tick-Killers
These efficient tick-killing machines can get through around 5,000 ticks in just one season, according to researchers who looked at the effect of six species of animals on tick populations. White-footed mice, as we know, are the primary host reservoir for ticks carrying Lyme disease in the US, while chipmunks, squirrels, catbirds, and veerys may also act as hosts for ticks. Opossum were found to be much more effective at eradicating ticks than any of these other animals, demonstrating that just because an animal can act as a host for ticks does not make it a net promoter of Lyme disease.
Foxes – Net Defenders Against Lyme
The same can be said of foxes, who likely carry ticks on their fur but who are also primary predators of white-footed mice, helping to make our towns and cities safer in regards to Lyme disease. Opossums pick up a lot of ticks and some of these will feed on the animals’ blood, spreading infection. However, the opossums lick the ticks off their fur and eat them, with around 90% of the ticks they do pick up ending up being eaten, killed, and excreted in their faeces.
Opossums might look a bit odd, then, but along with myths regarding the animals’ susceptibility to rabies (they’re immune) it seems that we should also thank these hapless nightlurkers for their part in keeping our streets free of Lyme disease.