Jude C. Anosike

Cysticercosis of Slaughter Cattle in Southeastern Nigeria

Abstract:  The incidence of cysticercosis due to Taenia saginata in both local and exotic breeds of cattle slaughtered for meat in southeastern Nigeria between November 1999 and April 2002 is reported. The examination of various organs of 25,800 cattle in 10 major abattoirs of this region showed that 6750 (26.2%) were infected with Cysticercus (C.) bovis. The prevalence rates varied from one abattoir to another while the rates of cysticercosis in local and exotic breeds varied significantly (P > 0.05). Sixty percent of all the infected animals had cysts. The tongue, cardiac, and masseter muscles were the main predilection sites of the cysts. Out of 11,720 male cattle, examined, 3215 (27.4%) had cysts of C. bovis while 160 (13.6%) of the 1180 female animals investigated were infected. There was an inverse relationship between the ages of the animals and prevalence of infection with C. bovis (r=−0.8743, P < 0.05). Monthly occurrence of the cysts in the animals revealed an upsurge of infected animals during the dry season. The epidemiology and epizootiology of Taenia saginata and C. bovis in relation to the veterinary service agencies and public health planners in southeastern Nigeria are highlighted.

Endemicity of vesical schistosomiasis in the Ebonyi Benue River valley, South Eastern Nigeria

The investigation on the prevalence of patent and clinically severe infections with Schistosoma haematobium was carried out amongst inhabitants of Ebonyi Benue river valley, South Eastern Nigeria between August 2000 and June 2001. The inhabitants are predominantly farmers. Of the 3296 subjects examined from 15 randomly selected villages in the valley, 776 (23.5%) were excreting the eggs of S. haematobium in their urine. Infection rates varied between 18.9% and 30.6%. The severity of infection calculated by arithmetic mean egg counts (AMEC) and geometric mean egg counts (GMEC) varied significantly between the age groups and the villages (P < 0.05). The prevalence and severity of infection increased with age from 0 to 25 years and decreased thereafter. Symptoms associated with the disease include visible hematuria (63.1%), suprapubic pain (10.3%) and stranguary (9.9%). While 65 positive persons had more than one symptom, 64 of the positive persons had no noticeable symptoms. Visible hematuria showed moderate sensitivity and high specificity for the disease. Female genital schistosomiasis (FGS) of the lower reproductive tract was recorded in 19 females of child bearing age that complained of severe suprapubic pain. Eight snail species were recorded in the stagnant ponds and both Bulinus globosus and B. truncatus were infected with schistosome cercariae. The factors contributing to these observations and feasible control measures are discussed.

Dracunculiasis in the north eastern border of Ebonyi State, south eastern Nigeria

Between January and August 2000, a house-to-house survey of dracunculiasis was conducted in 15 communities along the north eastern border of Ebonyi State, south eastern Nigeria. Of the 3,777 subjects examined, 192 (5.1%) had active cases of guinea worm comprising 109 males (5.5%) and 83 females (4.6%). Infections were observed in all age groups. Of the 3,777 persons examined, 2,092 (55.4%) had ever been infected in the area. Protruding adult female Dracunculus medinensis worms were found predominantly on the lower limbs (80.2%), but also on the scrotum (9.4%), umbilicus (3.1%) groin (2.6%), buttocks (20.8%) and chest (1.6%). Prevalence of dracunculiasis had no significant sex, age and occupation related differences (P > 0.1). All the 47 stagnant ponds in the area were infested with cyclops while the 6 streams and 13 newly constructed community wells were free of cyclops. Of the five species of cyclopoid copepods found in the stagnant ponds, only Thermocyclops oblongatus nigerianus and Mesocyclops aequatorialis harboured guinea worm larvae. The efforts of the endemic communities, government and international organizations in guinea worm eradication in these areas are discussed.

The varied beneficial effects of ivermectin (Mectizan) treatment, as observed within onchocerciasis foci in south–eastern Nigeria

Abstract In the treatment of humans, ivermectin (Mectizan®), a semi-synthetic macrocyclic lactone, is now primarily used as a rapid microfilaricide. The drug has several other benefits, however, and these have recently been investigated in five states in south–eastern Nigeria, where there have been mass treatments with ivermectin, for the control of Onchocerca volvulus, for more than 10 years. Between the January and December of 2005, 3125 adult onchocerciasis patients (each aged ≥20 years and known to have at least one clinical sign of onchocerciasis) were enlisted, clinically examined and interviewed. Relevant data were collected in the interviews, using a structured, pre-tested questionnaire, and in personal and focus-group discussions. Overall, 612 (19.6%) of the subjects reported that they had had nodules that had disappeared following repeated doses of ivermectin, although only 83.8% of the 612 attributed their nodule clearance to ivermectin (the other 16.2% being unsure of the cause). A larger percentage of the subjects (24.6%) reported that they had expelled intestinal helminths following the last round of ivermectin treatment (i.e. been dewormed). Other side-benefits reported in the study were improved vision (11.7% of subjects), reversal of secondary amenorrhea (4.5%), increased appetite (22.3%), reduction in arthritic or other musculo–skeletal pain (7.9%), reductions in the severity of body itching (18.5%) and skin rash (17.3%), darkening of leopard skin (6.6%), improved libido in men (6.6%), and clearance of head lice (4.5%). If, via health education, the local communities could be made more aware of the side-benefits of ivermectin treatment, the sustainability of the on-going programme of community-directed treatment with ivermectin (CDTI) in south–eastern Nigeria would probably be improved.

Control of endemic dracunculiasis in Ebonyi state, south-eastern Nigeria.

A field study was carried out in Ozibo and the Ebonyi local government area of Ebonyi state, south-eastern Nigeria to determine the effectiveness of several intervention strategies in the control of endemic dracunculiasis in that area. During the initial study prior to the application of such measures, 14,421 subjects were examined. A total of 8,688 (60.2%) persons had either Dracunculus ulcers or emergent worms. Sex-related prevalence rates were 56.1% and 63.9% for males and females respectively. Age specific prevalence rates increased with age in males, whereas highest infection rates were found in females younger than 20 years. Twenty-eight months after the introduction of intervention strategies the prevalence rate fell by 85.1% to 9% (males: by 88.2% to 6.6%, females: by 83.0% to 10.8%). Reduction rates of more than 90% were observed in males aged 10 to 19 and in females aged 0 to 9 years. Intervention measures included systematic pond treatment, distribution or replacement of filters, intensive health education, provision of hand-dug wells, regular bore-hole installation/rehabilitation as well as active case detection, containment, management, and prompt reporting. Active involvement of the endemic communities, governments and the Global 2000 staff regarding the control efforts is a necessity towards the final eradication of the disease in the near future. The relationship between some of these intervention strategies and community development are highlighted.

Human infections with Moniliformis moniliformis (Bremser 1811) Travassos 1915 in South-Eastern Nigeria

To control human infections with intestinal helminths, the residents of parts of Imo state, Nigeria, have recently been subjected to yearly, community-based, mass treatment with ivermectin (Mectizan®; Merck & Co.). Young children (aged < 5 years) and pregnant women are excluded but most other subjects are each given a single, oral dose of the drug (2, 6 or 12 mg for those who are 95.5-125.5, 125.6-149.9 or at least 150 em tall, respectively). To investigate the effect and usefulness of this treatment, each treated individual is asked to provide a stool sample to the drugdistribution team at least 36 h post-treatment. For the collection of stools, a coded, 2-litre container, with a wide opening and screw cap, is quarter-filled with 4% formalin solution and given to each treated person who agrees to provide a sample. The stool specimens are collected, taken to a central laboratory and checked for helminths, using either formolether concentration (King, 1973) or Kato smears (Martin and Beaver, 1968). Any adult worms encountered are removed, counted and identified. During the processing of stools from approximately 24 000 treated subjects, 19 of the samples were found to be contain the eggs and/ or adults of the acanthocephalan Moniliformis moniliformis (Bremser 1811) Travassos 1915. The eggs were identified as those of Mo. moniliformis on the basis of their small size (70-120 X 30-60 pm), their characteristic ovoid shape, and the triple-layered envelope (Ikeh et al., 1992). Of the 19 subjects found to be infected, each of whom had received only one treatment with ivermectin, two were aged < 10 years, eight were between 11 and 20 years and the other nine were older ( > 20 years). Most (11) were male, and all were either hired palm-wine tappers (nine) or farmers (10). Seven of the cases were symptomatic, with tinnitus/ dizziness (three cases), general stomach pains (two cases), watery stools (one case), or (unexplained) abdominal discomfort around the umbilicus (one case). All 19 infections were treated, apparently successfully, with further doses of ivermectin. Moniliformis moniliformis has a cosmopolitan distribution, rodents being the usual definitive hosts and cockroaches and beetles the (proven) intermediate hosts (Miyazaki, 1991). Human infection with this parasite appears to be rare. However, the possible epidemiological significance of such infection was recognised more than a century ago. It was then that S. Calandruccio experienced diarrhoea, acute abdominal pain, exhaustion, somnolence and violent ringing in his ears and head 19 days after he infected himself experimentally with the acanthocephalan (Grassi and Calandruccio, 1888). About 15% of the coprolites, from a grain-eating prehistoric man, found in a cave in Utah (U.S.A.) contained Moniliformis eggs (Moore et a/., 1969). In Iran, Moayedi et a/. (1971) found a 4-month-old boy, who had had repeated episodes of watery stool, accompanied by irritability, coughing and sweating, to be infected with Mo. moniliformis. Al-Rawas et a/. (1977) documented the first recognised case of infection with this parasite in an Iraqi child. However, it was another 25 years before the first report of human infection with Mo. moniliformis in Nigeria. This infection was in a 45-year-old man who presented at the health clinic of the University of Jos, in northern Nigeria, complaining of general body weakness, occasional giddiness and (curiously, given the similar observation in the present study) intermittent burning sensations around the umbilicus (Ikeh et a/., 1992). This case was treated, again apparently successfully, with four tablets of niclosamide (Yomesan®; Bayer) given as a single dose, although no adult Mo. moniliformis were ever recovered. In south-eastern Nigeria (in households and range lands in the rural communities of

Mansonelliasis amongst nomadic Fulani herdsmen of south-eastern Nigeria

This study was undertaken to investigate the prevalence of Mansonella perstans infection amongst the nomadic Fulani herdsmen of south-eastern Nigeria. Physical examination of 709 consenting nomads for clinical manifestations of M. perstans infection was carried out between September 2004 and August 2005. This was followed by parasitological examination of blood samples collected by finger prick method to identify microfilariae (mf). Data collected was stratified by bush encampment in various states, age and sex and analyzed using the chi-square test. Overall, 43 (6.1%) of 709 nomads were infected. Ebonyi State bush encampments have the highest prevalence (9.5%), followed by Imo State encampments (6.5%) with Enugu State as the least (4.5%). There was slight significant variation amongst various bush encampments (p Keywords : Mansonella perstans, nomadic Fulani herdsmen, south-eastern Nigeria. Nigerian Journal of Parasitology Vol. 28 (2) 2007: pp. 83-86