A rare, dangerous parasite is spreading fast across North America in both humans and animals

There’s no denying that, after fatal viruses impacting life, the world is still not ready for another fatal outbreak, which is growing faster than you can ever imagine, as this dangerous parasite can affect not just humans but can also impact animals.

Here’s all you need to know about this unsettling parasite that has been quietly expanding its footprint across North America and has officially arrived in the Pacific Northwest. For the first time, scientists have detected the dangerous tapeworm Echinococcus multilocularis in wild hosts along the contiguous U.S. West Coast. Read on to know more…The fast progression of fatal parasiteWhile the parasite is a long-standing public health issue in Europe and Asia, it used to be incredibly rare in North America.

That shifted about 15 years ago when infections began popping up in dogs and people across Canada and the American Midwest. This latest discovery confirms the worm is still pushing into new territory.

How does it affect local coyotes?Researchers from the University of Washington recently tested 100 coyotes in the Puget Sound region and were surprised to find that 37 of them carried the parasite. The results of their study were published in the journal PLOS Neglected Tropical Diseases.

As per a study published in the journal of Science Daily, Dr. Yasmine Hentati, the study's lead author and a recent environmental and forest science graduate from UW, noted that while a handful of people and numerous dogs have gotten sick across North America, the parasite had never been seen in the Pacific Northwest until earlier this year. Finding it in a third of the local coyote population was a major wake-up call.Interconnected Life CycleThe tapeworm relies on a complex back-and-forth cycle between different animals to survive, and it rarely makes its primary hosts sick. Coyotes, foxes and other wild canids are the hosts for this parasite. These animals can have thousands of worms living inside them without getting sick. They just pass the parasites' eggs into the environment when they go to the bathroom. The next step is when rodents eat the eggs by mistake when they are looking for food in areas where coyotes have been.

When the eggs get inside the rodent they go to the liver and form cysts that can make the animal weak or even kill it. Then the cycle starts again when a coyote catches and eats the infected rodent.

Danger to both humans and dogsHumans and dogs can also get this parasite. It is not supposed to happen to them. This is because the parasite does not want to be inside humans or dogs; it just happens by accident. If the parasite does get inside humans or dogs, it can cause a lot of harm.

People can contract the parasite by accidentally swallowing the invisible eggs—often by eating food contaminated with dog or coyote feces.In humans, this triggers a dangerous condition called alveolar echinococcosis. The disease causes slow-growing, cancer-like tumors to form in the liver and other organs. Because these cysts grow so slowly, symptoms might not appear for 5 to 15 years, making it incredibly tough to diagnose.

Without treatment, the infection can be fatal. In fact, the World Health Organization ranks it as the third most important food-borne illness globally.Keeping your Pets safeDogs face a double threat depending on how they encounter the parasite. If they ingest coyote feces containing eggs, they can develop the same life-threatening liver cysts that humans get. However, if they eat an infected rodent, they might just carry the adult worms in their gut and shed eggs, turning them into a hidden source of infection for their owners.How to protect petsAs per the study, Dr. Guilherme Verocai, who is an expert on parasites, suggests that people who own dogs make sure their pets do not hunt rodents or eat animals. He further adds that it is very important for dog owners to take their dogs to the vet on a basis test their stool and give them medicine to prevent worms.The growing threatSo far it is not common for people to get infected in the United States and there have been no reported cases of people getting infected on the West Coast. Also, seven dogs have gotten infected in the states of Washington, Oregon and Idaho since 2023 and Dr. Guilherme Verocai and other experts suggested the importance of dog owners being careful with their dogs and the threat of parasites like these. As Dr. Hentati explained, coyotes have high infection rates because raw rodents are their primary diet, whereas most pets aren't eating wild rodent livers.However, scientists are highly concerned because of the specific strain involved.

Decades ago, a mild "tundra variant" of the parasite existed on remote Alaskan islands. Genetic testing shows that the current outbreak is fueled by a much more infectious strain of European origin.