Sparganosis is a disease that can be transmitted from animals to humans, and so it is a zoonosis

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You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Sparganosis is a zoonosis that occurs occasionally in humans. It is contracted from amphibians, reptiles or mammals

A type of tapeworm called pseudophyllidean cestodes can be transmitted to humans and they are therefore zoonoses. In the lifecycle of these parasites the metacestode stage is called a sparganum and infection with this parasite which forms cysts is called sparganosis.

Sparganosis has been reported to occur in many countries but it is most common in eastern Asia. Humans are an intermediate host for the parasite and  infection occurs in several ways :

  • Drinking water containing infected copepods, which are small crustaceans found in plankton  - (first intermediate hosts). In the normal life-cycle of the parasite these would be ingested by second intermediate hosts (vertebrates) including :
    • Amphibians
    • Birds - eg chickens
    • Fish
    • Non-human Primates
    • Wild Pigs
    • Reptiles - eg snakes
    • Small mammals - eg rodents, insectivores
  • Eating raw or undercooked second intermediate hosts : amphibians (eg frogs), birds (chickens), wild pigs, reptiles(eg snakes) or mammals 
  • The parasite can also penetrate skin, so another route of infection is through direct contact with infected vertebrates.

The final hosts of sparganum mansoni 1 are cats and dogs which (like humans) may eat one of the second intermediate hosts.

Once ingested by a human the spargana larvae undergo visceral migration and can end up in many tissues where they grow to be as long as 14 inches in length. They most often form a nodule under the skin or in superficial muscles or fascia.  A local tissue reaction forms around the white coloured parasite which results in an itchy, inflamed and  painful lump. If surgically accessible they can be removed otherwise there is no treatment. In other locations, such as the eye, the parasite can cause serious injury - in this case resulting in blindness. Occasionally they can migrate to the brain.

Diagnosis involves identification of the parasite following surgical removal or in tissue sections form lump biopsies. Patients may also have an increased white blood cell count and eosinophilia.

Prevention involves avoiding eating potentially infected foods and contaminated drinking  water.


Updated October 2013