PREVALENCE OF SCHISTOSOMA HAEMATOBIUM AMONGST CHILDREN

PREVALENCE OF SCHISTOSOMA HAEMATOBIUM AMONGST CHILDREN OF SCHOOL AGE AND ASSOCIATED URINARY ABNORMALITIES IN  EBONYI NORTH

CHAPTER ONE
INTRODUCTION 
Schistosoma haematobium is the causative agent of urinary Schistosomiasis also called Bilharziasis named after a young German parasitologist Theodor Bilharz, who first identified the parasite during autopsy in Egypt .(Roberts; 2010).
   It is an important digenetic  trematode and is found  in Middle East , India , Portugal and Africa. It afflicts the poor , rural villagers , especially school aged children , women and fishermen who lack access to safe water and sanitation , and where daily activities bring them into direct contact with infected water sources.

The adult organism are found in the venous plexuses around the urinary bladder and their released eggs traverse the wall of the bladder causing haematuria and fibrosis of the  bladder. The bladder become calcified and there is increased pressure on  Ureters and kidneys otherwise known as hydronephrosis . Inflammation  of the genital due to S. haematobuim  may contribute to the propagation of HIV (Leutscher et al ;2005).
  Studies have shown the relationship between S haematobuim and the development of squamous  cell carcinoma of the bladder (Khurana et al;2005).Schistosomiasis or Bilharziasis is generally applied to blood fluke infections caused by different species of blood  flukes namely  Schistosoma haematobuim , S. mansoni ,S. japonicum, S .intercalatum ,and  S .mekongi.(Nnochiri;1975).

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  Schistosomiasis is one of the major communicable disease of public health and socio-economic importance of the tropical and sub- tropical  region. The disease has been reported to be the second  to malaria as a source of human morbidity ( Ukoli; 1992). It is one of the major occupational hazards in  rural areas of developing countries. It is second to none in prevalence among water borne parasitic diseases(WHO;1985) and (Doumenge et al;1987).
  Schistosomiasis or Bilharziasis is not only endemic in Nigeria but  is also known to be prevalent in all countries of Africa (Wurapu et al ;1989). According to estimates of WHO,(1984), at least 200 – 300 million are infected with the disease (and another 600 million are at risk of infection) and endemic in 74 developing countries. Estimates suggest that 85% of all schistosomiasis cases are now in sub –Saharan Africa. ( Chitsulo l et al;2000).
   WHO, (2012) estimates that at least 243 million  people required treatment for schistosomiasis  in 2011 and the number of people treated in 2011 was 28.1 million. Nigeria as one of the countries known to be highly endemic  for urinary schistosomiasis with estimated 101.28 million persons at risk and 25.83 million infected (Uneke et al;  2007). The estimates for morbidity and mortality in affected populations are high with school age children.
Two forms of Schistosomiasis are recognized in humans .They are urinary schistosmiasis caused by S . haematobium .It is also known as the vesical  type of the disease characterized by passage of blood stained urine ( haematuria ).The other form is called intestinal schistosomiasis which is caused by S. mansoni, S .japonicum and  S .intercalatum .
   Some urinary   abnormalities are associated with  S haematobium  infection, The presence of blood in urine known as haematuria  and protein in urine known as proteinuria has been recorded in several studies on S . haematobium infection.
  Persons affected by S. haematobium  may develop cough , fever, skin inflammation and tenderness of the liver because the spined eggs attach to vital organs and cause tissue degeneration.  Later stages of the disease may be characterized by the swelling and damaging of the bladder , liver  and other organs .The eggs of S. haematobium can clog the bladder neck  and cause infection .Many researchers have also observed damage on other body structures . 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 Schitosoma also cause Medical problems ,Schistosoma haematobium is  the only species that affects the Human urinary system ( Basch; 1991).
    Urinary Schistosmiasis is often chronic and can cause pain, secondary infection, kidney damage as well as cancer. Painful or difficult urination (dysuria), Blood in urine ( haematuria), urethral obstruction, kidney damage from obstruction of urine ( obstructive nephropathy) ,no urination ( anuria) are all accompanied signs and symptoms. The parasite also causes chronic urinary tract bacterial infection .The bladder may also develop tubercles, polyps, ulcers, sandy patches, cystitis cystic, and or leukoplakia that are visible upon endoscopic examination.
    Late complication after years of infection includes squamous cell carcinoma
 Incidence of urinary schistosomiasis  in Nigeria and surveys reporting the prevalence in some towns and communities has been documented viz: Cowpear;(1973), Ozumba et al;(1989), Adewumi et al;(1990), Emejulu et al ;(1994), Akogun;(1996), Edungbola et al;(1998),Daniel et al;(2001), Adeyeba et al;(2002),  Nnoruka;(2000), Idris et al (2002), Ekejindu et al;(2002), Okon et al;(2002),Alozie et al (2004), Onwe ;(2005),Uneke et al;(2007), Uwaezuoke et al;(2007) Obiukwu et al ;(2008),Adeoye et al;(2008),Nmorsi et al;(2007), Mbata et al (2009), Odikamnoro et al (        ), Okwelogu et al (2012).
      But out of these studies non has incorporated the associated  urinary abnormalities in the research work.
AIMS AND  OBJECTIVES
Work has not been done on the  prevalence of  S. haematobium amongst children of school age and associated urinary abnormalities in Ebonyi North.  Hence this work therefore is aimed at
1.         Determining the prevalence of urinary schistosomiasis and associated urinary abnormalities amongst children of school age in Ebonyi North.
2.         Determining the socio- economic and environmental factors that can lead to urinary schistosomiasis amongst the children of school age and the communities at large .
3.         Developing (based on the outcome of the study) strategies to control/eradicate the disease in the community.
 
CHAPTER TWO
LITERATURE REVIEW
Records indicates that Bloody urine was a well recognized disease symptom in Northern Africa in ancient times. About  1950 BC Egyptian Pharoahs wrote of urinary bladder disturbances that probably were Schistosoma  haematobium .
The hieroglyph used to denote the disease was a dripping penis.Atleast 50 reference to this condition have been found in surviving Egyptian papyri and calcified eggs of S. haematobium have been found in Egyptian mummies dating from about 1200BC. ( Roberts et al ;2010).
The first Europeans to record contact with S.haematobium were surgeons with Napoleon’s army in Egypt(1799-1801). They reported that hematuria was prevalent among the troops, although the was unknown. Over 50 years later precisely 1851 a young German pathologist Theodor Bilharz discovered the parasite that caused it while working at Kasr El-Eini Hospital in Cairo. It was discovered some years later that 30% to 40% of the population in Egypt bore infection of S. haematobium .
In 1858 Weinland proposed the name schistosoma but it was named Bilharzia by Cobbold after its discoverer Theodor Bilharz. This later name became widely accepted throughout the world. However, the strict rules of zoological nomenclature decree prefers Schistosoma  and is thus the current name of the parasite  today. Schistosoma  is an apt name, referring to the “split body” (gynecophoral canal)of the male.     
While information was accumulating on biology of S. haematobium some people began to doubt whether it was a single species or whether two or more species  were being confused. This problem was more confounded by the observation in some  patients of eggs with lateral  spines and others with terminal spine in both urine and feces.  
In 1905 Sir Patrick manson decided  that intestinal and vesicular(urinary bladder) schistosomiasis were distinct disease caused by distinct species of worms. He derived his conclusion after examining a man from West Indies who had never been to Africa and who passed laterally spined eggs in his urine (Robert et al ;2010).
Sambou in 1907 name the parasite producing laterally spined eggs Schistosoma mansoni .  
In 1915 Leiper an English Scientist discovered the intermediate snail host. By working in  Egypt, he discovered that cercariae emerging from the snail Bulinus spp could infect the vesicular veins of various mammals and they always produce eggs with terminal spines. Also those emerging from a different snail,Biomphalaria spp ,infected intestinal veins and produced laterally spined eggs.
GEOGRAPHICAL DISTRIBUTION
Schistosomiasis is estimated to occur world- wide , infecting 200million people and endemic  in 74 developing countries while leaving over 600 million people at risk (Chitsulo et al;2000).
The infection is most prevalent in Africa , Middle East ,South America, Caribbean,  Southern China and South east Asia (WHO;1985).Estimates suggest that 85% of all Schistosomiasis is endemic in 54 African countries and the Eastern Mediterranean. It  is found in much tropical and sub-tropical Africa and also occur in Iran ,Saudi Arabia, Syria, Arab republic, Yemen in Maharashtra state in India and in several Indian ocean islands including Mauritius, Pembina, Zanzibar and some smaller island off the East African coast(Cheesbrough;2003).
   S. mansoni,the causative agent of intestinal schistosomiasis is prevalent in 52 countries. It is wide spread in many African countries, Madagascar, and parts of Middle East, South America( especially Brazil), and the west Indies. S .mansoni occurs with S. haematobium in 41 Countries of Africa and the Eastern Mediterranean .( Cheesbrough;2003).
S. japonicum is widely distributed in mainland China, parts of the Philipines and Western Indonesia .
S. mekongi is found in Lao people’s Democratic Republic, Cambodia, and Thailand in the Mekong River Basin ( Cheesbrough;2003).
S .intercalatum is limited in its distribution mainly to West and Central Africa , that is Zaire, Gabon and Cameroon .Republic of Sao Tome (island off West Africa) recently recorded infection of S. intercalatum.
Cheesbrough,(2003) noted that the development of irrigation channel and Dams,  for hydroelectric power and flood control have altered the distribution of Schistosomiasis in several countries,example Aswan lower dam in the United Arab Republic(Egypt), Akosombo Dam in Ghana,the Senna Dam in Sudan, Kainji Dam in Nigeria ,and the Kariba Dam in Zimbabwe. Water development projects for water conservation equally contributed.                            
 In Nigeria, pocket of foci of infection have been documented in various parts of the country. In the Northern region, S .haematobium is marked particularly by heavy infection rates. These include the territory extending from Katsina, Kano, Zaria and Kaduna to the Western frontier, in the region of Birinin Kebbi ,Argungu, Kankiya area.( Nmorsi et al;2005). In these area Schistosomiasis associated with haematuria infection rate of up to 60%-95% have been recorded.(onwe;2005).
Other Northern region include Wulgo region of lake Chad basin, the riverine area along the Niger from Wawa to Pategi and Bida, Niger( Cowper;1963).
 In the western region, S. haematobium is universally distributed. The highest infection rates are found in Ibadan, Oyo, Abeokuta and Epe area. Cowper, (1963) has also reported the endemic foci in Ogoja province and around Owerri of the Eastern region .Akinkugbe,(1962) states that urinary infection due to S. haematobium is endemic all over Nigeria ,but later work by  Cowper,(1963) has narrowed the endemicity in Nigeria down to Western and Northern regions. However several works by Ekejindu et al;2002, Uneke et al;2007, Uwaezuoke et al;2008, Mbata et al ;2009. All indicate  prevalence in the Southern  parts of Nigeria.

MORPHOLOGY
  Schistosoma spp. are generally similar structurally with slight differences as listed in Table 1
Comparative Morphology of the three primary species of Human Schistosomes
Characteristics                      S. haematobium           S. mansoni          S .japonicum
Tegumental papillae:  Small tubercles    Large papillae    Smooth
Size:
Male
Length                              10-15mm                 10-15 mm            12-20 mm
Width                   0.8-1.0 mm              0.8-1.0 mm         0.5-0.55mm
Female
Length                              ca.20mm                  ca.20mm              ca.26mm
Width                               ca.25mm                   ca.25mm              ca.0.3mm
Number of testes:           4-5                              6-9                           7
Position of ovary:        Near midbody            In anterior half          Posterior to                  midbody
Uterus :     With 20-100eggs at one time    Short; few eggs at one time   Long; contain 300 Eggs.
Vitellaria:  Few follicles, posterior to ovary  Few follicles, posterior to ovary  In lateral view, Posterior quarter Of body Egg:   Elliptical, with sharp terminal spine   Elliptical, with sharp lateral spine  Oval to almost spherical:
112-170 m by 40-70 m   4-175 m by 45-70 m 70-100 m by 50-70 m
                                                                                                                            
TABLE by: (Roberts et al; 2010)
They are not flat, leaf like worms like other Trematodes. They have narrow elongated bodies and have separate sexes ( Ochei et al;2000).Considerable sexual dimorphism exists in the genus, males being shorter and stouter than females.
The male worm (Fig 1) is colorless, cylindrical and measures 10mm-20mm. The males have a ventral, longitudinal groove ,the gynecophoral canal, where the female normally resides.
The mouth is surrounded by a strong oral sucker, and the acetabulum is near the anterior end.There is  no pharynx .The paired intestinal ceca converge and fuse at about the midpoint of the worm and then continue as a single gut to the posterior end.
Males possess 5-9 testes according to species, each of which has a  delicate Vas deferens. The later dilates to become a seminal vesicle, which opens ventrally through the genital pore immediately behind the ventral sucker. The integument is finely tuberculated.
 The female worm (Fig.2) is cylindrical, threadlike, often reddish black in color and longer than the male, measures 20mm in length  and 0.35mm  width and has pointed extremities.( Roberts et al;2010). The sucker of the females are smaller and not so muscular as those of the males and tegumental tubercles if  any are confined to the ends of females.The ovary is anterior or posterior to or at the middle of the  body, and the uterus is correspondly short or long   depending on species.
The eggs (Fig.3) are compact, elongated spindles, dilated in the middle and they measure about 112-170um in length by 40-70um breath.


TRANSMISSION  AND LIFE CYCLE
This occurs in Fresh water when intermediate snail host release infective form (cercaria) of the parasite into wter. People become infected by direct physical contact with water containing infective cercaria( while swimming, washingcloth ,bathing in water and during agricultural work). Bulinus snails are mainly the intermediate hosts for S. haematobium while Biomphalaria is for S. mansoni and amphibious Oncomelania snails is for S. japonicum.
 When released from the snail host, the infective cercariae swim, penetrate the skin of the human host, and at the same time shed their forked tails (bifurcated) becoming Schistosomulae. The schistosomule
Migrate through the tissue and finally enters a blood vessel. Through the blood it is carried to the heart, the lung and then to the liver. The worm begin to grow and mature into an adult within the liver sinusoids. Eventually they migrate against the portal blood flow into the mesenteric, vesical or pelvic venules.
The delicate adult worms reside in the venules in pairs ,the female lying in the gynecophoric canal of male. Depending on the species, eggs are passed daily into the venules (e.g about 200 by S. haematobium, 300 by S. mansoni and 3500 by S. japonicum). Egg deposition occurs in the venules of the bladder ( for S. haematobium ) or small venules of the intestine and the rectum( for S.mansoni and urethra or into the intestine and are ultimately released from the body in the urine or feaces . The eggs are immature when first laid and contain a mature miracidium by the time they are released in the urine and feces.
When the egg comes in contact with water the mature miracidium is liberated. It swims actively in the water  till it finds a suitable snail host which varies from species to species. The Miracidium penetrates the snail intermediate host and develops through the  stages of a mother sporocyst  which produces daughter sporocyst that finally develop into cercariae with a forked tail .These cercarae are released by snail into water to infect man through skin penetration ( Ochei et al;2000).
EPIDEMIOLOGY
Urinary Schistosomiasis  caused by S. haematobium is reportedly endemic in 53 Countries  in the Middle East and most of the African countries ( Chitsulo et al;2000). Nigeria is one of the countries known to be highly endemic for urinary schistosomiasis with estimated 101.28 million persons  at risk and 25.83million people infected (Uneke et al ;2007).
Human waste in water containing intermediate hosts is the single most important epidemiological factor in schistosomiasis and availability of suitable snail species (Roberts et al;2010).Survival of these parasites depends on human habits of polluting water with their own feces.
Human are apparently the only important host in most area of high endemicity,( Markel et al;1996).In Africa non human primates insectivores and wild rodents are found to harbor the schistosmes where as in Brazil several species of marsupials and rodents carry the infection. The importance of these reservoir hosts in maintaining and spreading the disease to human probably varies from one area to the next.
Extension of the disease into new areas still occurs with the migration of infected people and the Agricultural Development of virgin land where the snail host is present. Irrigation and the establishment of artificial bodies of water combined with unsanitary practices may quickly result in new foci of high endemicity. Since the snail intermediate host is entirely  aquatic, the aqueous environment (water flow, vegetation, water temperature, and PH ) determines snail density and distribution.( Markel et al ;1996).
  As far as it is known, human remains the most important  host for S. haematobium. The snail intermediate host apparently has less stringent requirement for water temperature than snail host of S. mansoni. This may partly explain the relatively  wide distribution of S. haematobium on the African continent (Markel et al;1996).
 In some areas of high endemicity in East Africa ,the snail lives in relatively small bodies of water that may dry up during part of the year. The snail the estivate  while buried in the mud but retain the infection  and resume shedding of cercariae when the rain season begins.   
Other factors relating to snail intermediate host include presence of right species for transmission, the reproductive capacity of these snails,  the number of cercariae  shed at a given time and seasonal variation in snail infection  rate ( Anosike et al ;2003).
 Immigration and population movement has introduced the infection to new areas and many people from non endemic areas have moved to areas where transmission occurs. Other factors that influence the amount of Schistosoma haematobium   infe ction  in an area include those related to human behavior, local custom , tradition, religion and the pattern of water used for economic and recreational activities such as swimming, fishing, irrigation, and washing( Onwe;2005).
Clearly, economic and education level of population will influence transmission of the disease, and age and sex are important factors as well. Males usually show the highest rates  of infection and the most intense infections.The most hazardous age is the second decade of life( Roberts et al;2010).           
Nmorsi et al, (2007) in a study assessing  the ova of Schistosoma haematobium in  the  urine of 138 volunteers  Ihieve ogben Edo state Nigeria revealed 43 positive result (31.2%)  with children having higher prevalence of urinary Schistosomiasis 30 (41.1%) than their adult counter parts. This was attributed to high exposure factor among the children as had been previously reported by Nmorsi et al,(2005) and Egwunyenga et al ,(1994).
Also in a study of the prevalence of urinary Schistosomiasis in ogbadibo Local Government Area of Benue state Nigeria , out of 657 urine samples examined ,300(46.6%) showed  the presence of S haematobium .Of the 300 positive samples 152(23.13%) were from males and 148(22.52%) were from females. In addition Uneke et al,(2007) in a survey of S. haematobium conducted among school children in Ohaukwu and Onicha local Government area of Ebonyi state Nigeria indicates that out of a total of 876 pupil examined 235(26.8%) were infected with S .haematobium a total of 129(27.01%) were males while 106(26.6%) were females of those infected supporting the fact that males are more infected than the female counter part . This was equally supported by the study conducted by Okwelogu et al, (2012) .This may be attributed to high exposure of the males who are mostly involved in recreational activities of Swimming and Agricultural endeavours.
 In a study of the prevalence and intensity of infection with S. haematobium amongst primary school children of Taga Tanzania in East Africa ,the analysis of S. haematobium infection in four urban and four rural primary schools in the area . Out of the 2270 children examined 38.4% were infected.
In urban school 23.1% of 1411 children were infected compared to 63.6% of 859 children in rural school. Prevalence was higher in rural school children than urban school children. This   probably is due to the level of exposure  of urban and rural children. The urban children were not very much exposed to fetching water from streams like the rural children except in situation where the tap water is not available (Bailey et al;1970).
According to Anosike et al,(2003) in the investigation on the prevalence and severity of infection with S. haematobium amongst inhabitants of Ebonyi/Benue river Valley, South eastern Nigeria between August 2000  and June 2001 showed that of 3296 subjects examined 776(23.5%) were excreting the eggs of S. haematobium in their urine . The prevalence and severity of infection increased with age from 6 to 25 years. This was attributed to the presence of infected snail host in the stagnant ponds of which many snail species were recorded including Bulinus globosus  and Bulinus truncates.
Cowper,(1963) stated that infection is rare in infants below 4 to 5 years. The highest egg output occurs between 12 and 20 years. The infection rate is generally highest among children of 6 to 8 years by (Malataway et al; 1984) , 10 to 14years by (Bruce;1990). The reason according to Malataway et al is that at 6 to 8years the only hobby of children is swimming and that at age of 9-11 years they start other activities like reading, footballing and  TV watching. This confirms with the work of Cowper,(1963) who in school surveys in the western region in Nigeria  recorded an infection rate of up to 20% in children under 14years.
SYMPTOMS  AND PATHOGENICITY
Following penetration of the skin by cercariae of Schistosome that infects humans a transient reaction may be seen .Petechial hemorrhages occur at the site of penetration with some localized edema and pruritus which reach a maximum in 24 to 36 hours and disappear in 4 days or less.(Markell et al; 1996). During the succeeding 3 weeks there may be transient toxic and allergic manifestations. These may be very mild and may pass unnoticed or there may be generalized malaise, fever, giant urticaria, vague intestinal complaints and so forth, partly depending on the intensity of infection.                                                                            
Migration of the worms throughout the lungs may cause cough or hemoptysis, soon the developing Schistosome reach the liver , acute hepatitis may develop. When the fluke reach the mesenteric or vesical venules and egg laying commences ,the acute stage of the disease is seen. The unset of this stage may occur 1 to 3 months after infection (Markell et al;1996).
Symptom of the acute stage may range from mild to severe, and the degree of reaction is not necessarily proportional to the number of parasites involved. Clinical disease at this stage is usually seen only in relatively heavy infection or in persons recently arrived in an endemic area. With the extrusion of eggs through the wall of the intestine or bladder , there may once again be generalized malaise, fever, urticaria, abdominal pain, and liver tenderness.
 In S. haematobium infections , there is often hematuria at the end of micturition. While in S .mansoni or S. japonicum infections there may be diarrhea or dysentery at this stage . The eggs are responsible for much of the pathology associated with the disease. Some of the eggs are trapped in body tissues. Immune reactions to eggs logged in tissues are the cause of the disease (Ogbeide et al;2004).
As soon as the eggs are produced, initially they are trapped in the fine venules. The eggs liberate a number of enzymes which facilitates their passage to the lumen of the bladder or intestine. In S. haematobium infections, the spine on the egg may cause haematuria  (Ochei et al;2000). Urination become painful and is accompanied by progressive damage to the bladder, ureters and then the kidneys. Bladder cancer is common in advanced cases (WHO;1985).
IMMUNOLOGICAL   RESPONSE:As the eggs are deposited in tissues  their antigens invoke an immune response in the host leading to the formation of granulomas around the eggs in tissues. The wall of the intestine or bladder become inflamed and thickened causing mechanical obstruction. Some eggs are swept into blood circulation and deposited in the liver and other organs in the body .Cerebral symptoms are commonly seen in S. japonicum infection while pulmonary involvement is more common with S. haematobium infections.(Ochei et al;2000)
URINARY  ABNORMALITIES:  Urinary abnormalities are often associated with S. haematobium infections. Light infections are usually asymptomatic. Dysuria, urinary frequency and haematuria are early symptoms and signs, but in endemic areas  they are so frequent as to be in large measure. Nmorsi et al, (2005) found a close association between eosinophiluria, proteinuria, haematuria specific gravity and turbidity in the urine with the presence of S. haematobium ova in urine. Ramsay, (1952) in his survey of Schistosomiasis in Northern Nigeria found that in sokoto area practically everybody suffers from gross hematuria at some point in early life. Terminal hematuria is usually the first sign of infection. Eosinophiluria is a constant finding in urinary Schistosomiasis. Chronic bacteriauria  is common with numerous pus cells in urine. Obstructive uropathy occurs primarily in persons with high total egg burden. Bladder cancer usually  a squamous cell carcinoma,is seen much more frequently in patients with heavy S. haematobium infections than in the general population. (Markell et al;1996). The cancer occurs primarily in areas of the bladder where there has been heavy egg deposition. It is thought that these heavy egg concentrations promote urothelial carcinogenesis. A nephrotic syndrome is occasionally seen in both S. mansoni and S. haematobium infections.
LABORATORY DIAGNOSIS
Microscopic identification of eggs in urine or stool remains the most practical method for diagnosis of Schistosomiasis . According to Ochei et al, (2000) there are two methods in use for the detection of Schistosoma eggs in urine.
1.         The sedimendation/centrifugation technique which is less sensitive but cheaper and simpler to perform.
1.      The filtration technique which is used when quantitative information is required.
2.      Detecting eggs in a rectal biopsy or bladder mucosal biopsy is also another method of diagnosis when urine examination is negative or unreliable due to egg encapsulation in the tissues (Cheesbrough;2003). The biopsy tissue can be crushed between two slides and examined microscopically to identify the species. If the preparation is too thick, add a drop of 4% KOH to clear the tissue. Digest the tissue in 4% KOH at 370c for 6 to 18hours. Centrifuge and examine the sediment for ova.
3.      Serodiagnosis is not very useful because of cross reactions with other helminthes, slow immunological response of the host and persistent elevated titres even after successful treatment (Ocheiet al;2000) and (Roberts et al;2010). Though a diagnostic technique taking advantage of the polymerase chain reaction (PCR) to detect a parasite DNA may offer a significant improvement.
Other techniques like intradermal test , flocculation test can be adopted for field use. However these methods are used only as complement to the urine microscopic examination method.

URINE EXAMINATION BY SEDIMENTATION/CENTRIFUGATION TECHNIQUE:
Finding the eggs or occasionally the miracidia of S. haematobium in urine . A quantitative report can be required  and determined by the number of eggs/10ml of urine.
The excretion of S. haematobium eggs in urine is highest between eggs in urine is highest between 10.00 h and 14.ooh with a peak around midday (Cheesbrough;1998 ). Cheesbrough, (1998) noted that a heavily infected persons may sometime present no eggs in urine sample due to the irregular pattern of egg excretion. Also neither excercising before passing urine nor collecting terminal urine (that is the last few drops of urine)  increase the number of eggs present in the  specimen as was once thought (Cheesbrough;1998). And to avoid miracidia hatching from the eggs, precaution should be taken by keeping the specimen in the dark.
PROCEDURE
1. Collect 10ml of urine in a clean dry container.
2. Report the appearance of the urine
3. Transfer 10ml of well mixed urine to a conical or centrifuge tube and centrifuge at 500-1000g to sediment the Schistosme eggs ( avoiding at centrifuging at a greater force because the eggs may hatch. In the absence of a centrifuge the urine can be allowed to stand and the eggs to sediment by Gravity for 1hour.
4. Discard the supernatant fluid .Transfer all the sediment to a slide , cover with a cover glass and examine the entire sediment microscopically using the 10x objective with the condenser iris closed sufficiently to give good contrast.
5. Count the number of eggs in the preparation and report the number per 10ml of urine . If more than 50eggs are present there is need to continue counting. Such count indicates heavy infection (Cheesbrough;1998)
FILTRATION TECHNIQUE.
Filtration is the most sensitive rapid and reproducible technique for detecting and quantifying  S .haematobium eggs in urine. However, the  polycarbonate membrane filters used in filtration technique are expensive .Other types of filters like Nytrel woven filters can equally be used.

MATERIALS REQUIRED :  includes:
--10ml  syringe.
--Syringe filter holder ( swinnex type) 13 diameter.
--Polycarbonate membrane filter of 13mm diameter and 12-14um pore size. This can be disinfected  with bleach and be reused several times.
PROCEDURE:
1.         Using blunt-ended forceps , carefully place a polycarbonate filter on the filter support of the filter holder. Re-assemble the filter holder and attach it to the end of 10ml Luer syringe.
2.         Remove the plunger from the syringe and fill the syringe to the 10ml mark with a well mixed urine .Replace the plunger. Holding the syringe over a beaker or other suitable container, slowly pass the urine through the filter.
3.         Remove the filter holder and unsecrew it. Using blunt ended forceps, carefully remove the filter and transfer it face upwards to a slide. Add a drop of physiological saline and cover with a cover glass.
4.         Using the 10x objective with the condenser iris closed sufficiently to give good contrast , examine systematically the entire filter for S. haematobium eggs and report  the number per 10ml urine .( Cheesbrough;1998).

N:B   Differentiating non-viable from viable Schistosome eggs on a filter can be done by  staining a preparation with 1% trypan blue in physiological saline. A drop of stain is added and the preparation is left for 30minutes at room temperature.
Non-viable eggs will stain blue while the viable eggs will remain unstained.

PREVENTION  AND CONTROL
According to Roberts et al, (2010), the control of Schistosomiasis as with many infectious diseases involves a multifold approach which includes;
1.         Education or public health awareness of the populace to prevent transmission.
2.         Massive  chemotherapy or curing of infected persons.
3.         Control of vectors/intermediate host propagation.
3.         Protective vaccination.
Okwelogu et al,(2012) agrees with these measures while Uneke et al ,(2007) implored the integration of methodologies and managerial tools to improve preventive strategies with emphasis on health education, information and communication.
Education of the population though potentially very effective is often exceedingly difficult due to low level of literacy, poverty, customs and traditional belief of the people involved. However, Education is the prerequisite for all control measures, since without understanding of the life cycle of the parasite attempts at its eradication are doomed to failure. With education programs brought to the people, it has been demonstrated in areas such as China that progress can be made in parasite eradication ( Markell et al;1996).
Differences in the snail hosts of the various Schistosome spp.in some cases dictate different control measures. Mollusciciding and  biological control through the use of snail eating fish or birds or even competing species of snails as has been done with some success in Puerto Rico and Brazil (Giboda et al;1997), environmental modification or various combinations of these measures.
Proper disposal of urine and feaces keeps eggs from hatching to initiate the cycle . This may be difficult to enforce in places where cultural and religious practices of people is tied to it. Also places where human excrement is of great economic importance being used as fertilizer, should be discouraged.
Other challenges of prevention is on teaching people to avoid snail infested waters when their economic livelihood depends on planting crops such as rice in these waters and where potentially snail –infested waters is the only kind available for bathing, washing cloths and so forth.
Niclosamide, a chloronitrosali-cylanilide , applied as a 1% lotion to the skin before contact with snail infested waters seem to have some value in preventing penetration of cercariae  ( Abu-Elyazeed et al 1993).
Certain plants example (Balanites aegyptica ) were cultivated for their molluscidal properties (Nigeria;1933).
In 1984, the WHO committee on the control of Schistosomiasis, recommended a strategy for morbidity control with chemotherapy as the major operational component (WHO; 1993). This was a  departure from the previous strategy of transmission control where the major aim was to eliminate the intermediate host snails. In areas of high prevalence, chemotherapy especially through school health programmes provides the most cost effective means for control.
Repeated chemotherapy ensures that levels of infection are kept below those associated with morbidity (WHO/TDR; 2004). Key elements of the control package consist of ensuring the availability of praziquantel in primary health care services and the regular treatment of high risk groups (school-age children and special occupation groups such as fishermen and irrigation  workers.
VACCINATION
The development of an effective vaccine would have great potential value in the control of schistosomiasis and this area of research is active ( Roberts et al; 2010).
Schistosomiasis has been controlled in many regions such that it is no longer a major health problem in Japan, China, Iran, Mauritius, Morocco, Saudi
Arabia etc. Thus with an adequate health infrastructure resources and political will , the available tools for the control of schistosomiasis can be used effectively (WHO;2004).

CHAPTER   THREE
MATERIALS AND METHODS
STUDY AREA:
Ebonyi state was created out of Enugu and Abia state  in 1996. The state is located in the south Eastern part of Nigeria. It is bound in the North by Benue state , East by Cross River state and  West by Enugu state.
The approximate population of the state is 2.093 million. There are thirteen local Government areas in the state which is divided into three senatorial district – Ebonyi North, Ebonyi Central and Ebonyi South. Ebonyi North is made up of four local Government areas—Abakaliki, ohaukwu, Ebonyi and Izzi local Government Areas respectively . But the major inhabitants are the two language spoken tribes of  Ngbo and Izzi people. While the Izzi people occupy three local Government area of Abakaliki, Izzi and Ebonyi, Ngbo people only occupy Ohaukwu LGA.
The major economic activity of these people is farming with very few people engaged in white collar jobs. The major sources of water supply to the people is from Rivers, Dams, Streams, Stagnant ponds , few shallow hand dug wells which are found in few rich families and
Bore holes provided by Government in some areas. These ponds, stream, Dams and rivers harbor most  of the snail intermediate hosts from where the effective stage of the parasite called cercariae emerge ready for transmission.
The people are equally massively engaged in Agricultural farming like Rice farming which keeps them in constant contact to water surfaces. The people are infected when  they come in contact with water from contaminated ponds and streams during farming, fetching water washing and swimming. The mode of infection is by the penetration/piercing of the skin by the cercariae .

MATERIAL AND METHOD
A total of 500 pupils were sampled from seven primary schools namely Central School Ngbo, Hill Top primary School Ngbo, Amaeffia Community primary School Ngbo, Igbeagu Central School Izzi, Junction primary School Nwezenyi, Oguzoronweya Primary School Ozibo and Okaria nkaleke community primary school.
The age range of the children were between 6-18yrs and their sex were also noted. The Teachers and pupils were enlightened on the relevance of the study especially the public health significance. The  method of urine collection was also explained to them. After this the pupil were randomly  selected. The children were given serial number and containers were distributed noting on the container their age and sex . Collection was done and immediately taken to the laboratory for immediate examination
METHOD OF SAMPLE COLLECTION
Clean universal containers labeled ( Name, sex and serial number) were distributed to the pupils randomly selected  in each primary
 School . The pupils already enlightened were re-instructed on how to collect the urine samples, particularly to include the last few drops passed (terminal urine) .Collection of urine samples started normally between 11am and 1pm.
TRANSPORTATION  OF COLLECTED SAMPLES
At the end of the collection exercise each day, the urine samples were re-checked and carefully packed into the storage box for immediate transportation to the laboratory for examination avoiding exposing the sample to light that will induce hatching of the parasite.
LABORATORY METHODS OF ANALYSING THE URINE SAMPLES
1.         Macroscopic Method: This involves noting the appearance of the urine sample. The colour of the urine sample were noted ,some smoky brown, bloody, turbid and cloudy appearance were noted.
Each urine sample were poured into clean 10ml centrifuge tube and properly labeled .
Chemical Examination of the urine was carried out on each sample using commercially prepared test-strip (Example, Combi 9 urine test-strip ) noting the various parameters like Glucose, Protein, Blood, Urobilinogen, Nitrite, Bilirubin and PH etc.
2.   Microscopic Method: This was done in line with Cheesbrough,(1998) recommendation for Sedimentation Technique for Schistosoma haematobium .Thus 10ml of urine were poured in to the centrifuge testtube. The urine samples were centrifuged at 1000g for 5minutes.After centrifugation the supernatant fluid was decanted and the sediment was mixed and a drop was placed on  a clean, grease free slide. It was covered with a cover glass and examined using x10 objective and x40 objective of the microscope in search of the S haematobium ova.

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