Prevalence and diversity of cystic echinococcosis in livestock in Maasailand, Kenya

Abstract

Cystic echinococcosis (CE) is a zoonotic disease caused by several members of the Echinococcus granulosus species complex. In East Africa, several species/strains are known to occur in livestock and humans, but host preferences, relative frequencies and spatial distribution of these taxa are poorly known. Here, we contribute livestock data for Maasailand of southern Kenya. Total CE prevalence was 25.8 % in cattle (151/587), 16.5 % in sheep (71/430) and 10.8 % in goats (21/194), which is a significant increase compared to surveys done about three decades ago. The majority of cysts occurred in the liver (56 % in cattle, 70 % in sheep and 65 % in goats). Molecular characterization by PCR-RFLP and sequencing of parts of the mitochondrial nad-1 gene was done for a subsample of 285 cysts. E. granulosus G1 was dominant in all host species (200 of 201 cysts from cattle, 68 of 69 from sheep and 11 of 15 from goats); the remaining taxa were Echinococcus canadensis G6 (one cyst from sheep, four from goats) and Echinococcus ortleppi (one cyst from cattle). Considering cyst fertility, sheep appear to be the most important hosts for E. granulosus G1, while goats were found to be suitable hosts for E. canadensis G6 (three of four cysts were fertile). For the first time, E. ortleppi was found in cattle from southern Kenya. Our data show an intense and possibly increasing level of CE transmission in southern Kenya, and the predominance of E. granulosus G1, which appears to be particularly pathogenic to humans, calls for urgent control measures.

Basic and applied problems in developmental biology and immunobiology of cestode infections: Hymenolepis,Taenia and Echinococcus

“… indicated that brain CE caused by E. canadensis (G6) was due to primary infection of the brain without hepatic lesions. This is in contrast to all other reports of E. canadensis , which indicated hepatic lesions with metastasis to the brain . It remains unclear whether this difference is due to unique genetic characteristics of the parasite, the host, or both, with genetic background postulated to be important in Iranian cases of Echinococcus .…”

A Cross-sectional Serological Study of Cysticercosis, Schistosomiasis, Toxocariasis and Echinococcosis in HIV-1 Infected People in Beira, Mozambique

“…A recent epidemiological study in Kenya looking at the prevalence of hydatidosis in cattle, sheep and goats shows a significant increase compared with data about three decades ago [17]. Even the introduction of livestock from other countries after the civil war could be a factor involved in echinococcosis in a country like Mozambique, with such an abundant canine population in its rural environment.…”

Taxonomy and molecular epidemiology of Echinococcus granulosus sensu lato

“…Other than this, the host range (including human pathogenicity) is unknown; it had not been found in 353 wildebeest (Connochaetes mearnsi) in the Masai Mara conservation area of Kenya, although it is widespread there in carnivores. Likewise, it was not present among 279 genotyped Echinococcus cysts recovered from livestock from the vicinity of Kenyan national parks (Addy et al, 2012). While E. felidis has not yet been found in any canid, the susceptibility of lions as definitive hosts is not a distinguishing feature for this taxon.…”

“…Given the ubiquitous presence of cattle and dogs as suitable hosts, the rarity of this parasite is perplexing. It may be explained by the fact, that, even in traditional pastoral societies, cattle are mostly sold alive and slaughtered in distant locations, so transmission to the local dog population is inhibited (Addy et al, 2012).…”