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alveolar echinococcosis in north america

We expect to fill the gaps in knowledge on the risk of exposure to Echinococcus multilocularis for domestic dogs, animal health practitioners and dog owners in Alberta

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Alveolar Echinococcosis in humans and dogs

Although rare, AE occasionally occurs in humans and  dogs, when it happens, they develop a severe condition frequently culminating in liver failure. It can be a lethal infection if the infection is left untreated.

Why is it relevant to study Echinococcosis in dog populations in Alberta?

It is important to surveil canine populations as they have close interactions with wildlife and humans within Albertan cities. The collection of data on the prevalence and risk factors of echinococcosis is key prior to developing prevention strategies for the community. No epidemiological study has been conducted to assess the true incidence of this infection in North America. No epidemiological study has been conducted to assess the true incidence of this infection in North America. 

How is this parasite transmitted to humans?

Humans ingest infectious eggs accidentally in contaminated food or having close interaction with dogs. However, there is evidence that contact with dogs is the strongest risk factor for getting the disease.

what is the ROLE of dogs in the the URBAN lifecycle of Echinococcus multilocularis?

Dogs are DUAL PARTICIPANTS.

They can act either as definitive hosts contracting intestinal Em infections and spreading the helminthic eggs through their faeces, but also as aberrant intermediate hosts, ingesting eggs from the environment or autoinfecting themselves during an intestinal infection, and developing canine Alveolar Echinococcosis (AE).

And how is this parasite transmitted to humans?

Humans are accidental hosts.

Humans become accidental hosts of Echinococcus multilocuris when they ingest infectious eggs in contaminated food or having close interaction with dogs. However, there is evidence that contact with dogs is the strongest risk factor for getting the disease.

ALVEOLAR ECHINOCOCCOSIS IN HUMANS AND DOGS

Alveolar echinococcosis (AE) is caused by infection with the larval stages of the tapeworm, Echinococcus multilocularis (Em), following ingestion of eggs from the environment.

AE results in the formation of vesiculated tumor-like lesions within the livers of intermediate hosts, primarily rodents. Normally, definitive hosts (wild and domestic canids) are not receptive to infection via eggs ingestion, instead they typically host adult tapeworms in the small intestine and release eggs that will be shed into the environment through faeces. Although rare, AE occasionally occurs in humans and  dogs, when it happens, they develop a severe condition frequently culminating in liver failure. Nevertheless, AE should always be treated in a promptly manner as it is a disease that may lead to lethal outcomes.

Why is it relevant to study alveolar echinococcosis in canine populations in alberta?

Despite recent reporting of several cases of canine AE in Canada, no epidemiological study has been conducted to assess the true incidence of this infection in North America, and there are no clear clinical guidelines for diagnosis, treatment or prevention of this disease.

Veterinarians often struggle to diagnose AE in dogs, due to a lack of understanding of this disease and due to its perceived rarity, it is often not included on their list of differential diagnoses. Diagnosis usually is considered only when clear liver involvement is detected by medical imaging and subsequent histological and molecular examination of liver biopsies reveal AE. Although, shedding of eggs in feces can be detected through floatation techniques in canids acting as definitive hosts, this is not a diagnostic test for AE. Often by the time a diagnosis of AE is made the disease is too advanced to treat and mortality is high.

The significance of our project

From an epidemiological perspective, we expect to fill the gaps in knowledge on the risk of exposure to Echinococcus multilocularis for domestic dogs, animal health practitioners and dog owners in Alberta.

From an ecological perspective, we will be able to provide information about the contribution of dogs in the urban cycle of Echinococcus multilocularis and the risk factors associated with its transmission to wildlife and humans.

AN EXPANDING RESEARCH FIELD

Join a growing movement of people around the world who are working to understand the impact of zoonosis and emergent diseases in their local communities.

A joint venture with our partners