Soil-Transmitted Helminth Infection In School Children In South-Eastern Nigeria: The Public Health Implication

摘要

The prevalence of STH infections was assessed among schoolchildren in Onicha, south-eastern Nigeria, using standard parasitological technique. Of the 510 children examined, 86 (16.9%, 95% CI, 9.38-24.34%) had helminth infections. The males were more infected than the females (18.3% vs 15.5%). Individuals aged 4-6 years old had the highest prevalence of STH infection (27.0%, 95% CI, 16. 62-37.38%). The helminths identified were Ascaris lumbricoides (10.8%),hookworm (4.3%), Trichuris trichiura, (1.2%) and Strongyloides stercoralis (0.6%). The prevalence of STH infections increased with increase in the number of persons in the household and the difference was statistically significant (χ 2 = 21.02, df = 3, P<0.05). Stunted growth by 1.6m and 0.04kg weight loss were recorded among the infected children. Treatment of STH infections in school-age children may improve growth but health education can be an effective and safe substitute for repeated deworming and reducing the opportunity for the emergence of drug-resistant helminthes. Introduction Soil-transmitted helminth (STH) infections represent a major public health problem in poor and developing countries and have constituted a universal burden which does not only depend on regional ecological condition but also on local standard of social and economic development of the people [1]. More than one dozen different species of soil-transmitted helminths infect humans, especially in the tropical and subtropical parts of the developing world. However, four nematodes in particular stand out because of their widespread prevalence and distribution that result in hundreds of millions of human infections. These include the large roundworm, Ascaris lumbricoides, the whipworm Trichuris trichiura, and two species of hookworm, Necator americanus and Ancylostoma duodenale [2]. It is estimates that almost 2 billion people are infected with one or more of these soil-ransmitted helminths, accounting for up to 40% of the global morbidity from infectious diseases, exclusive of malaria [3]. The greatest numbers of soil-transmitted helminth infections occur in tropical and subtropical regions of Asia, especially China, India and Southeast Asia, as well as Subsaharan Africa. Of the 1-2 billion soil-transmitted helminth infections worldwide, approximately 300 million infections result in severe morbidity, which are associated with the heaviest worm burdens [2]. The public health importance of STH infections ranked highest in morbidity rate among school aged children who often present much heavy worms infections because of their vulnerability to nutritional deficiency [4]. These infections have been shown to impact negatively on the physical fitness and cognitive performance of the pupils. Intestinal obstruction, anaemia, malnutrition, dysentery syndrome, fever, dehydration, vomiting and colitis are the major complications associated with STH infections [5]. STH infections affect most frequently children in developing countries and are associated with poor growth, reduced physical activity and impaired learning ability[6,7,8,9,10]. It is well established that indiscriminate disposal of human and animal faeces, poor personal hygiene, and inadequate water supply contribute to high levels of STH infections [11]. Soil-transmitted helminths are some of the most common and infective agents of mankind and are responsible for high morbidity and mortality throughout the developing world. This is of great importance in health of many populations in third world countries where illiteracy, poverty, and associated poor environmental sanitation practices have been implicated in the heavy burden of helminthiasis among children [11,12,13]. The relative contribution of environmental climatic and behavioural factors in the transmission of intestinal helminthic infections has been evaluated [14]. However, even more significant are the physical growth retardation, cognitive and educational impairments caused by heavy chronic