ALVEOLAR ECHINOCOCCOSIS IN WESTERN LOWLAND GORILLAS (GORILLA GORILLA GORILLA): ALBENDAZOLE WAS NOT ABLE TO STOP PROGRESSION OF THE DISEASE.

Abstract

Echinococcus multilocularis is the etiologic agent of alveolar echinococcosis (AE), a severe and potentially fatal larval cestode infection primarily affecting the liver. AE is known to occur in dead-end intermediate hosts, including humans and nonhuman primates. Between 1999 and 2016, AE was diagnosed in seven western lowland gorillas (Gorilla gorilla gorilla), all from a Swiss zoo. Six gorillas died of the disease. One individual is still alive, receives continuous albendazole medication, and shows no clinical signs. Most infected animals remained asymptomatic for years. Only one young gorilla showed early signs of acute discomfort and abdominal pain. In the final stage of the disease, affected animals died suddenly, or showed a short course of nonspecific but severe clinical signs, including lethargy, recumbency, abdominal enlargement, and anorexia. Postmortem examination confirmed hepatic AE complicated by peritonitis in most cases. Echinococcus multilocularis infection may remain undetected because of a very long incubation period. Hematological and biochemical parameters rarely showed abnormalities in this phase. Thus, inclusion of abdominal hepatic ultrasound examination and serology is recommended for early AE detection in routine examinations of gorillas in endemic areas or where food is potentially contaminated with E. multilocularis eggs. Ultrasound or computed tomography was useful to monitor progression and to estimate the volumetric extension of the hepatic lesions. Current medication with albendazole, which proved to be effective for human patients, was not able to stop progression of hepatic lesions in gorillas. Therefore, its therapeutic value remains questionable in gorillas. However, long-term oral albendazole treatment proved to be safe, and therapeutic plasma levels published for humans were achieved. Preventive measures such as thermo-treatment of food or vaccination of gorillas and other nonhuman primates should be considered in areas where E. multilocularis is present.

• Authors: Christian Wenker, Stefan Hoby, Fabia Wyss, Bernard Mengiardi, Renate Vögtli, Horst Posthaus, Peter Deplazes, Bruno Gottstein
• Journal: Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians (J Zoo Wildl Med) Vol. 50 Issue 1 Pg. 243-253 (03 01 2019) ISSN: 1042-7260 [Print] United States
• PMID: 31120685 (Publication Type: Case Reports, Journal Article)
• Copyright: © 2019 by American Association of Zoo Veterinarians.

Chemical References

• Anthelmintics
• Albendazole

Topics

• Albendazole (therapeutic use)
• Animals
• Animals, Zoo
• Anthelmintics (therapeutic use)
• Ape Diseases (diagnosis, drug therapy)
• Echinococcosis (diagnosis, drug therapy, parasitology, veterinary)
• Female
• Gorilla gorilla
• Male
• Switzerland
• Treatment Outcome