Studies on vesical schistosomiasis among rural Ezza farmers in the southwestern border of Ebonyi State, Nigeria.

Studies on vesical schistosomiasis and its snail vectors were carried out between October 2001-May 2002 among rural Ezza farmers inhabiting the southwestern border of Ebonyi State, Nigeria. The people are predominantly farmers. Of the 2,104 urine specimens examined in 10 communities, 466 (22.1%) comprising 305 (23.7%) men and 161 (19.7%) women were infected with visible haematuria as the predominant presenting symptom. Ezza people associate bloody urine with sexually transmitted diseases. There were no significant differences in the prevalence rates amongst various villages and sexes (p > 0.05). There was a gradual increase in the disease prevalence as the subjects' age increases. About 78.3% of the infected persons are aged 0-20 years. Statistical analysis revealed that the prevalence, intensity and visible haematuria were significantly more ( p < 0.05) in subjects under the age of 20 than subjects above 20. Among the infected population, 183 (39.3%) and 283 (60.7%) were excreting 50 eggs/10 ml urine and above 50 eggs/10 ml urine respectively. Lack of visible haematuria is a more valid indicator of the absence of vesical schistosomiasis. Of the various snails collected during malacological survey, mainly B. globosus were infected. Possible control measures are discussed.

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.

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.