In order to better understand Taenia crassiceps cysticercosis, 17 cases, from 10 French institutions, were analyzed: 14 in Lemur catta, 2 in Hapalemur alaotrensis and 1 in Eulemur coronatus. Unlike alveolar echinococcosis, T. crassiceps cysticercosis does not seem to have a precise geographical distribution across France.1
In this study, 53% of the affected lemurs were females and 47% were males. This almost equal sex ratio is in contradiction with the hypothesis of a gender predisposition for females.2 The age of discovery of the infestation varied between 4 years and more than 20 years. Forty percent of the cases were first identified at necropsy. In 33% of the cases, T. crassiceps cysticercosis was the cause of death, either by natural death or euthanasia.
Cysticercosis appears in various locations in the body: 9 cases had subcutaneous cysts, 8 showed muscle infiltrations, 6 with thoracic cysts, 5 with abdominal cysts, 1 with lymph node invasion and 1 with invasion of the spinal canal.
In one of the zoos with cases, 12 feces of local free-ranging definitive hosts (Vulpes vulpes, Canis lupus, Felis catus) were collected.3 One was positive for Taenia eggs in coproscopy. Three (one of each host) were positive for Taenia by PCR analysis. Preliminary sequencing data suggests this was not Taenia crassiceps. Investigation is still in progress.
As early macroscopic diagnosis is difficult, the development of an ELISA test is under consideration by a partner laboratory, using sera and parasitic lesions of infected lemurs.
1. Combes B, Comte S, Raton V, Raoul V, Broué F, Umhang G, Favier S, Dunoyer C, Woronoff N, Giraudoux P. Expansion géographique du parasite Echinococcus multilocularis chez le renard en France. Bulletin Épidémiologique: Santé Animale, Alimentation. 2013;57:16–18.
2. Sciutto E, Fragoso G, Diaz ML, Valdez F, Montoya RM, Govezensky T, Lomeli C, Larralde C. Murine Taenia crassiceps cysticercosis: H-2 complex and sex influence on susceptibility. Parasitol Res. 1991;77:243–246.
3. Freeman RS. Studies on the biology of Taenia crassiceps (Zeder, 1800) Rudolphi, 1810 (Cestoda). Can J Zool. 1962;40:969–990.