Celestine O. E. Onwuliri

Endemicity of schistosomiasis in some parts of Anambra State, Nigeria

Investigation on the prevalence of infections with schistosoma was carried out amongst inhabitants of two local government areas (LGAs), Nigeria between October 2007 and September 2008. A total of 2064 randomly selected subjects had their urine and stool samples examined for eggs of Schistosoma and 323 (15.7%) were excreting eggs of S. haematobium in their urine with geometric mean egg count (GMEC) of 10.1 eggs/10 ml of urine. No eggs of S. mansoni were found. Prevalence of infection varied between 12.8 and 19.8% between the LGAs, but the differences were not statistically significant (P>0.05). Prevalence also varied significantly between the age groups (P<0.05) with peak occurring among persons aged 11 to 20 years and decreased thereafter. There was a close association between haematuria and the presence of eggs of S. haematobium in the urine (P<0.05). People that tested positive for schistosomiasis were 26.4 times at greater risk (P<0.001) of haematuria as compared to those who tested negative. The result indicated 83.1% sensitivity and a specificity of 91.4%. Farmers (OR=2.31; P<0.05) were significantly at greater risk of schistosomiasis infection as compared to the artisans. The importance of these findings and their implications for control of the disease in Anambra State are discussed. Key words: Schistosomiasis, endemicity, Anambra State.

Clinical and parasitological aspects of onchocercal skin diseases in Nigeria.

An assessment of onchocercal skin disease (OSD) conducted in 38 rural communities in the Imo River Basin, Nigeria, between March 1999 and September 2000, showed that depigmentation (DPM) was the most prevalent lesion in persons with skin microfilariae (mf) (26.3%), followed by chronic papular onchodermatitis (CPOD) (18.1%) and acute papular onchodermatitis (APOD) (15.5%). There was no significant difference (P>0.05) in sex-related prevalence of OSD. While CPOD, lichenified onchodermatitis (LOD) and DPM were more prevalent in subjects over 30 years old, APOD was associated more with those aged less than 30 years. OSD occurred with concomitant itching in nearly 50% of subjects. The geometric mean intensity of infection was 13 mf/mg per skin snip.

Onchocerciasis in Imo state, Nigeria (2): the prevalence, intensity and distribution in the upper Imo river basin.

Human infection with Onchocerca volvulus was investigated in 13 rural communities in the Upper Imo River basin, Imo State, Nigeria between March 1997 and December 2000 using the skin snip method. Of the 3,311 persons examined, 889 (26.8%) had microfilariae. There were significant differences between communities in microfilariae prevalence and intensity of infection (P < 0.05). Sex infection was similar in males (26.8%) and females (26.9%); whereas farmers (46.6%) and fishermen (28.4%) were more affected than people in other occupations. The proportion of infected persons increased with age coinciding with the period when most clinical signs manifest. A significant proportion of the 889 persons with positive microfilariae skin biopsy had musculoskeletal pain (57.1%). Thirty-four (47.2%) of the 72 epileptics identified had positive skin biopsy in addition to other manifestations. The present findings show that onchocerciasis is a public health problem in the area. The use of ivermectin has reduced the incidence of the disease when compared with data from the pre-ivermectin era. This shows that Community Directed Treatment with Ivermectin (CDTI) campaign is successful and should be sustained until onchocerciasis is eliminated as a public health problem in the area.