The emergence of Taenia solium cysticercosis in Eastern and Southern Africa as a serious agricultural problem and public health risk

Abstract

Pig production has increased significantly in the Eastern and Southern Africa (ESA) region during the past decade, especially in rural, resource-poor, smallholder communities. Concurrent with the increase in smallholder pig keeping and pork consumption, there have been increasing reports of porcine cysticercosis in the ESA region. This article reviews the findings concerning the presence and impact of porcine cysticercosis in seven of the ESA countries. Most of the reported findings are based on surveys utilising lingual palpation and post-mortem examination, however, some also used serological assays. In Tanzania, community-based studies on porcine cysticercosis indicate a prevalence of 17.4% in the northern highlands district of Mbulu and a prevalence range of 5.1 Á/16.9% in the southern highlands. In Kenya recent surveys in the southwestern part of the country where smallholder pig keeping is popular indicate that 10 Á/14% of pigs are positive for cysticercosis by lingual examination. Uganda has the most pigs in Eastern Africa, most of which are kept under smallholder conditions. Preliminary surveys in 1998 and 1999 at slaughterhouses in Kampala indicated a prevalence of porcine cysticercosis between 0.12 and 1.2%, however, a rural survey in northern Uganda in 1999 indicated 34 Á/45% of pigs slaughtered in selected villages were infected. Additionally, a new survey of 297 pigs slaughtered in Kampala in 2002 indicated that pigs from the central region of the country were negative for cysticercosis while 33.7% of the pigs coming from the rural Lira district in the north were positive. Interestingly, 8 piglet foetuses removed from an infected slaughtered sow coming from Lira district were all found to harbour cysts of T. solium providing evidence of congenital transmission of porcine cysticercosis. In Mozambique, abattoir records indicate that porcine cysticercosis is present in all provinces of the country. A serological survey on pigs in rural Tete Province found 15% of pigs positive. In Zimbabwe, a retrospective study in official abattoirs around the country from 1994 to 2001 reported a mean prevalence of 0.34% which is in contrast to a post-mortem survey in 1999, which showed that the prevalence of porcine cysticercosis in rural west Zimbabwe where smallholder pig keeping is popular was 28.6%. In Zambia, abattoir records reported porcine cysticercosis in six of the nine provinces. Routine meat inspection of 1316 pigs at a slaughter slab in Lusaka showed that 20.6% of the pigs had cysticercosis whereas serological testing of 874 pigs at the same abattoir indicated that 56.6% were found to have circulating antigens of Taenia solium . Field surveys based on lingual palpation in Southern and Eastern Provinces of Zambia revealed prevalences of 8.2 Á/28.4 and 5.2%, respectively. South Africa has the largest number of pigs in Southern Africa and cysticercosis has been recognised as a problem in the country for many decades. There is strong evidence supporting the high prevalence of neurocysticercosis infect...

Evaluating the Efficacy of Teaching Methods Regarding Prevention of Human Epilepsy Caused by Taenia solium Neurocysticercosis in Western Kenya

“…7 The prevalence of porcine cysticercosis in Busia and Nyanza Districts of Kenya is between 10% and 14%. [8][9][10] In 1992, cysticercosis was declared a potentially eradicable disease by the International Task Force for Disease Eradication, [11][12][13] depending on eliminating reservoirs of T. solium . Because tests on live pigs, which have very low sensitivity and inspection systems at slaughter in most developing countries, are poor, 2 it is difficult to identify reservoirs of infected pigs .…”

Taeniosis-cysticercosis complex in individuals of a peasants' settlement (Teodoro Sampaio, Pontal of Paranapanema, SP, Brazil)

“…There is strong evidence supporting the high prevalence of Taenia infection in humans from resource-poor areas, especially in rural areas with deficient sanitation, low hygienic standards, and unusual customs, such as consumption of raw pork (Phiri et al 2003).Taenia solium and Taenia saginata are two taenids of great economic and medical importance, causing bovine and porcine cysticercosis and taeniosis in humans. The encysted larva, known as cysticercus from T. saginata and T. solium are found in cattle and swine, respectively, and the adult tapeworm of T. saginata and T. solium are found in man.…”

“…There is strong evidence supporting the high prevalence of Taenia infection in humans from resource-poor areas, especially in rural areas with deficient sanitation, low hygienic standards, and unusual customs, such as consumption of raw pork (Phiri et al 2003).…”

Evidence-Based Identification of the Most Important Livestock Related Zoonotic Diseases in Kampala, Uganda

“…According to LC1 leaders, pigs were slaughtered at pen-side and distributed to trading centres by traders, or taken alive to nearby trading centres and slaughtered at butcheries in all levels of urbanicity. In Kampala, there is a single abattoir that slaughters pigs at Wambizi where a veterinarian inspects pig carcases [35]. The percentages of pig farms selling to Wambizi abattoir in urban (5.2%) and periurban areas (4.5%) were low and no rural pig farms sold to this abattoir.…”