細菌学および寄生虫学ジャーナル

概要

Water Contact Activities and Prevalence of Schistosomiasis Infection among School-age Children in Communities along an Irrigation Scheme in Rural Northern Ghana

Francis Anto, Victor Asoala, Martin Adjuik, Thomas Anyorigiya, Abraham Oduro, James Akazili, Patricia Akweongo, Philip Ayivor, Langbong Bimi and Abraham Hodgson

Of the various trematodes that infect humans, schistosomes remain among the most prevalent, and the various forms of schistosomiasis still pose significant public health problems. The prevalence of schistosomiasis infection among in-school and not-in-school children resident in communities along the Tono irrigation canals in northern Ghana was determined. Stool and urine samples from random representative samples were parasitologically examined using the Kato-Katz and 10 ml urine filtration methods respectively. A total of 920 children (mean age: 11.0 yrs; range: 6-15 yrs; STD Dev: 4.6 yrs), 573 (62.3%) males and 347 (37.7%) females with 473 in-school and 447 not-in-school participated in the study. The prevalence of Schistosoma haematobium infection was 33.2% (305/920) whilst that of S. mansoni was 19.8% (95% CI: 17.3-22.5; 182/920). The overall prevalence of infection (S. haematobium plus S. mansoni) was 47.7% (439/920). Many more males (51.7%; 95% CI: 47.5-55.8) than females (41.2%; 95% CI: 36.0-46.6) were infected. Forty-six (5.0%, 46/920) children were infected with both S. haematobium and S. mansoni. There was no difference in the prevalence of infection (S. haematobium plus S. mansoni) among children in-school (48.4%; 95% CI: 43.8-53.0) and those not-in-school (46.5%; 95% CI: 41.8-51.3). There was a statistically significant difference in prevalence of infection among communities (P=0.0002); with the lowest level of infection in residents of Korania (29.9%; CI: 20.0- 41.4) and the highest among those resident in Kajelo (64.9%; CI: 51.1-77.1), with significant differences in levels of water contact activities (χ2 =6.69; P=0.04). The highest intensity of S. mansoni infection (115.6 epg) was in Bonia where the highest prevalence of blood stained stools was collected (5.5%). Overall, 2.8% (26/920; 95% CI: 1.9-4.2) of stool samples were blood stained, whilst 10% (92/920; 95% CI: 8.2-12.2) of children had haematuria. S. haematobium ova were detected in 98.9% (91/92) of blood stained urine samples. Children infected by S. mansoni were more likely to have blood stained stool (χ2 =32.7; P<0.0001). The prevalence of schistosomiasis infection in the irrigation project site is high, adding praziquantel to albendazole and ivermectin for distribution during the annual mass drug administration for filariasis and onchocerciasis control will be an effective way of reaching all at risk groups in the Kassena-Nankana district for the control of schistosomiasis.