1.0 Introduction
Schistosomiasis is also known as bilharzia or “snail fever”. It is a parasitic disease carried by fresh water snail infected with one of the five varities of the parasite schistosoma. Found predominantly in tropics and sub-tropical climates. (Chitsulo, 2000), schistosoma ranks second only to malaria as the most occurring parasitic disease in the tropics (chitsulo, 2000).
1.1 Background of the Study
The schistosomes or blood flukes belong to the class trematoda of the phylum platyhelmintes. They are parasites of the blood stream of warm blooded vertebrates. The species which infect man are schistosoma haematobium, s mansoni, s intercalum and s japonicum. They cause the disease known as schistosomiasis or bilharziasis (uyaeme, 2011).
Urinary schistosomiasis caused by fluke worm s haematobium is one of the most common tropical olisease which poses serious health hazard due to its associated morbidities. Globally, over 153 million people are infected with this parasitic infection (WHO1999). In Nigeria, a good number of foci infections have been documented in various parts of the country (Egwunyenga et al, 1994).
In developing countries, the true epidemiological picture appears difficult because of inadequate researches in this direction despite its relevance in planning and control in any locality. This problem is compounded by the poor habits of people in developing countries in visiting hospital, for treatment. Also, self medication is still practiced as manifested by anti-helmintic abuse. This act is worsened by presence of inadequate health facilities. One of the consequences of the self-medication of the anti-helminthics abuse includes the suppression of the egg laying capacity of the worms. The net effect is erroneous diagnosis using ova in urine in any locality. This may also become evident in sub clinical cases and period of immaturity of the worms when they are yet to commence egg laying. Another obvious difficulty occurs during the early stages of infections. Although the uses of serological diagnosis are available, poverty poses a serious impediment to the applications of serology in the epidemiological work in these countries.
The spined eggs are laid in water, the eggs hatch into ciliated miracidia which bore into the tissues of certain fresh water snails, the intermediate host. Within the snail, each miracidium forms a sporocyst which reproduces asexually to give rise to cercariae (Raven and Johnson, 1996 cercariae production may continue for several weeks, over 300 being produced each day from a single sporocyst. The cercariae leaves the snail and swim in the water. They gain entry into man, the final host, by penetrating the skin. once in the body system, the cercariae develop into the adult fluke where they cause schistosomiasis.
Characteristic / features
- They are dioecions i.e sexes are separate and there is sexual dimorphism
- The male and female always occur together and the larger male carries the slender female in it's ventral groove or gynaecophoral canal.
- They live in the blood stream of vertebrates.
- The eggs are not operculate and are usually armed with a spine.
- The furcocerous cercariae penetrates directly through the skin into the definitive host
- It is a water-borne disease with water snails as the intermediate host.
- There are two suckers, an oral and a ventral sucker (acetabulum).
- The alimentary canal consists only of intestinal caeca without an anus. (Uyaeme, 2011).
Habitat
Schistosoma haematobium occurs in the veins of the vessical plexus surrounding the urinary bladder of man. it is found throughout Africa, middle East and India. The skin or integument is spined. The snail hosts are members of the genius Bulinus which are fresh water snail. it is the agent of haematuria and in renal schistosomiasis, the eggs are voided via urine (Uyaeme, 2011).
Raven and Johnson (1996) stated that the wide spread, introduction of irrigation in the tropic has contributed greatly to the spread of this serious disease, by spreading habitats for the snails that carry the worms. The disease is an occupational hazard because people are infected due to the type of occupation (job they do). It is water borne, people that frequent stagnant water bodies like lakes, streams, ponds, dams e.t.c are at risk of being infected. The presence of the appropriate snail host in a habitat is also important in the disease transmission. Pollution of water with human faeces and urine due to bad sanitary habits or disposition of human wastes in water bodies is also important.
Economic importance
Schistosoma haematobium causes schistosomiasis also known as Bilharzia. Hosts of the parasites are humans and affect about 200 million people worldwide and is considered one of the most serious pathogenic infections today (chitsulo, 2000).
S haematobium is pathogenic to humans and causes spot of blood in the urine and sometimes in the stool, this leads to haematuria (Uyaeme, 2011).
S haematobium causes cough, fever, skin inflammation and tenderness of the liver because the spined eggs attach to vital organs and cause tissue degeneration. Later stages may cause swelling and damaging of the liver and other organs. The eggs of S haematobium can clog the bladder neck and cause infection chronic schistosomiasis raises the incidence of bladder cancer in many middle eastern countries (Roberts et al, 2000).
Calcified eggs embedded in the bladder wall increase the chances of blockage of the vessels. Although other species of schistosoma are also of medical importance.
S haematobium is the only species that affects human urinary system (Baschi, 1991).
Considering the high morbidity and mortality associated with Schistosoma infection in man, it is important that before any control measures can be attempted, a thorough knowledge of the disease pathogen, the epidemiology, the life cycle and the economic importance as well as the egg shape must be well understood.
1.2 Statement of Problem
There are reports of urinary schistosomiasis all over Nigeria, which constitute a public health problem particularly among children. (Sulyman et al, 2009). The distribution of the disease is focal, aggregated and usually related to water resources and development schemes such as irrigation projects, rice/fish farming and dams.(mafe et al, 2000). This disease is predominant in Agulu owing to the fact that this town is surrounded by a lake and the inhabitants frequents the lake, while some always get in contact with water because farming is their major occupation.
1.3 Significance of the study
The significance of this study is to determine the incidence of urinary schistomiasis among the inhabitants of Agulu. The importance of this study extends to revealing the contributory risk factors of the disease in Agulu and to suggest ways to control or prevent the disease.
1.4 Objectives of the study
- Determining the incidence of urinary schistosomiasis among the inhabitants of Agulu.
- Determining the socio-economic and environmental factors that can lead to urinary schistomiasis among the inhabitants of Agulu.
- Developing strategies to control the disease in the town.
1.5 Scope of the Study
This research work has been limited within Agulu and its environs. There are many school but only three primary school has been used. With this perspective, the analysis of the incidence of urinary schistomiasis among both male and females of different ages in Agulu must not be neglected for a better result.
1.6 Limitations of the Study
As a result of inadequate information, coupled with time and financial constraints, the study was not an easy one. Most of the inhabitants had the expression that giving out their urine should be seen as exposing themselves to danger hence their refusal to give out the sample, few refused as a result of ignorance and formal education.
…
