EPIDEMIOLOGY AND TRANSMISSION PATTERNS OF Schistosoma haematobium INFECTIONS IN CENTRAL EBONYI STATE, NIGERIA.
ABSTRACT
Study on epidemiology and transmission patterns of Schistosoma haematobium infections were carried out between July, 2013 and April, 2014 in 16 out of 47 communities making up Ebonyi Central zone Ebonyi State, Nigeria. This is to determine the prevalence of Schistosoma haematobium infection and its transmission patterns among the inhabitants of Ebonyi Central senatorial zone. Centrifugation method was employed to determine intensity of Schistosoma haematobium eggs in 10ml of urine. An overall prevalence of 19.0% (n = 342) was observed among the 1800 people examined. Infection was recorded in all the communities in the study area with Enyibichiri community (32.2%) recording the highest prevalence followed by Umuoghara community (25.5%) while Oshugbu community with 6.6% had the least prevalence. Across communities, the prevalence of Schistosoma haematobium infection differed significantly . More males 225(20.3%) than females 117(16.9%) were significantly infected in all the communities with haematuria as the predominate presenting symptoms. Infection prevalence was significantly higher (27.3%) among the age group 11 – 20 years. Statistical analysis revealed that the prevalence and intensity were significantly (P< 0.05) more among 11 – 20 years age group. In the moderate infection, those 11 – 20 years had significantly high intensity when compared with those of other age groups while peak intensity was recorded among 11 – 20 age group. Intensity of light and moderate infections varied significantly (P<0.05). Intensity of heavy infection in the different age groups was not significantly different (P>0.05). Highest prevalence of haematuria (62.3%; n=86) was recorded in the age group 11 – 20 years old while the least prevalence was recorded among group 31 – 40 years. Prevalence of haematuria differed significantly among different age groupsr (P<0.05). Famers had the highest infection rate (35.4%; n=149), followed by students/pupils (21.2%; n=117), civil servants (9.7%; n=38), traders (9.1%; n=23) and artisans (8.2%, n=15). Chi-square analysis showed a very highly significant difference among the occupational groups (P<0.05). Generally, human water contact activities in the study area revealed a marked seasonal variation in both the frequency and duration of water contacts. More contacts were observed in the dry season than in the rainy season. A cross-sectional study on the sex and age-specific water contact activities among various water sites showed that the frequency and duration of contact males made with water were significantly more than females (P<0.05). Bulinus globosus was incriminated as a major snail host of Schistosoma haematobium. Snail population increased during the rainfall but snail infection was higher in the drier months. Of the 48 Bulinus globosus collected, 11(22.9%) were infected or found to shed cercaria. Report from this study showed that the school children, teenagers and young adults are the population at risk of schistosomiasis infection and it will provide a guide for the treatment of community members and help in eradicating schistosomiasis infection in the study area. There is urgent need for a decisive control intervention which should by mass chemotherapy and focal application of molluscicides in the water bodies during the dry season.