Epidemiology of Dracunculiasis in Ikwo Local Government Area of Ebonyi State , Nigeria

^1*AMADI, ANC;   ²ANOSIKE, JC; ³IWUALA, MOE

¹Department of Biological Sciences, Michael OKpara University of Agriculture, Umudike,  P.M.B 7267,Umuahia, Abia State, NigeriaE – MAIL: an-amadi@ yahoo.com.
²Department oF Animal and Environmental Biology, Imo State University Owerri
³Federal University of Technology, Owerri Imo State, Nigeria.

Code Number: ja06027

ABSTRACT

Between April 1999 and March 2000 an epidemiological survey was conducted for prevalence and distribution of dracunculiasis in fifteen communities in Ikwo Local government area of Ebonyi State, Nigeria. A total of 4568 persons were examined out of which 640 (14.0%), had active cases of guinea worm. The disease was higher in males (15.0%) than in females (12.0%). However infection rates varied significantly among different villages, age and occupational groups (P<0.05) with fever (45%) and severe pain (35%) as their predominant symptoms. Disability associated with guinea worm infections in the area include crippling effect, lowered sexual activity and poor maternal attention (in females). Infection in the area depends on the source of water supply. Pond water users recorded more infection than the bore-hole/well users. Over 57.7% of persons examined filtered their water before drinking, while 26.13% did not supply treatment of any kind. The prevalence rate showed seasonal variations with 105 cases in the month of March (16.4%) and 6 cases in the month of August (0.94%). Endemicity of dracunculiasis was encouraged by behavioural and cultural inclinations. @JASEM

Dracunculiasis is a parasitic infection acquired by drinking water from ponds contaminated by cyclopoid copepods infected with third stage larvae of the parasite Dracunculus medinensis. Worm emergence is through the skin after a year of entering the infected person and this is usually associated with secondary bacterial infection. It has been called a neglected disease of neglected people since it strikes remote farming populations who have been passed over by national development efforts (Anosike et al 2002). Dracunculiasis is endemic in areas where the population depends for its domestic water supply on surface water especially stagnant pools and water holes, shallow unprotected wells and slow flowing streams (Kale 1977). Infection is especially likely under circumstance in which the same water source is used for drinking and bathing and in which people have to wade into to fetch water (Nwoke 1992). Various works on the disease and its vectors (Cyclops) have been extensively recorded in Nigeria and these include: Onabamiro (1954, 1956), Nwosu et al (1982), Edungbola (1983; 1984), Osisanya et al (1986), Fabiyi (1991), Nwoke (1992), Anosike et al, (2000), Amadi (2002). Ebonyi State is known endemic area in Nigeria (Hopkins 1998). Efforts towards the disease eradication and control of the vectors as well as their complication still constitute a public health problem as many elsewhile communities that were thought to be free from the disease hitherto return endemic. The present investigation was designed to assess the status of the disease and possible strategies towards the final eradication and control.

The study was carried out in fifteen communities of Ikwo Local Government Area located in Eastern Part of Ebonyi State Nigeria. The area consists of seasonal streams and ponds in which a larger portion of the population depends for water. Rainfall is seasonal, it runs between the months of May to September and measures about 200cm to 250cm, while the dry season is from October to April. A daily temperature of 30°C is recorded. The inhabitants of the area are mainly farmers while others engage in petty trading, civil service work, fishing and palm wine tapping. Due to the swampy nature of the grassland majority of the farmers engage in the cultivation of rice. Other crops cultivated are yam, cassava groundnut etc.

The natural streams and ponds serve the inhabitants throughout the year and due to the drastic reduction in volume of these water bodies during the dry season, people inevitably wade into them to bath, fetch water for drinking and other domestic uses.

Data Collection: Between April 1999 to March 2000, a total of 4568 persons resident in Ikwo L.G.A. were examined physically for the emergency of guinea worm. House to house interview of patients and case search methods as in most guinea worm studies (Belcher 1975, Udonsi 1987a&b, Anosike et al 2000; Amadi 2002) were also adopted to determine among other things the number of people with active cases and those ever infected. The data was stratified by sex, age, occupation, source of drinking water, site of infection seasonality of outbreaks and disabilities associated with the diseases were identified.

Between April 1999 and March 2000, fifteen communities of Ikwo Local Government Area were studied for dracunculiasis. Of the 4568 persons examined, 640 (14%) had active cases. Infections with guinea worm showed a significant variation (P<0.05) between communities. Dracunculiasis was recorded in all the communities sampled with Ndufu Amagu (42.0%) having the highest and Echialike (4.1%) the least (Table 1).  Of the 4568 persons examined, 2597 (56.9%) persons had ever been infected in the communities (Table 2). Of 4568 persons examined, 2093 were males while 2475 were females. In addition 231 (15.6%) and 319 (12.93%) were infected males and females respectively (Table 3).

Table 1    Prevalence of dracunculiasis in Ikwo area of EbonyiState, Nigeria

Table 2:  Distribution of those with active cases and those ever infected in Ikwo area of Ebonyi State

The distribution of dracunculiasis in relation to sex and disability in endemic area is shown in Table 4. Of the 4568 persons examined, 2767 (60.6%) were infected. This was based on both active and those ever infected in the area. Of these, 1417 (67.6%) males and 1350 (54.6%) females were infected. However, 213 (15.3%) and 109 (7.2%) of males had crippling effect and lower sexual activity respectively.  Infection is significantly higher in the 0-40 years of age (P< 0.05) than in other age groups (Table 5). Fever was the most common symptom suffered by patients in the area. This is usually prior to the emergence of the worm. Both fever and severe pain were recorded in all the age groups.

Table 3:   Prevalence of dracunculiasis in relation to sexes in the area

In all the age groups, there exist persons with active cases as well as those ever infected.  The prevalence of dracunculiasis in persons within the 0 – 40 years age group are significantly higher than in those of 41 years and above. The pattern of infection in relation to worm emergency showed that adult worms of D. medinensis could emerge from any part of the body.  Higher number of worms emerged from the foot (172) followed by the ankle (680) and the knee (62). Some worms emerged from the breast (0.9%) and buttocks (1.6%) (Table 6). Table 7 illustrated the prevalence of guinea worm infected regarding source of water supply/use in the area. These people depend mainly on streams, stagnant pond and seasonal stream. About 8.8% and 5.0% of well and borehole users respectively were infected. Observation in the field showed that due to ignorance and people’s belief, most of the villagers do mix borehole and well water together with pond water. To them they believe that pond water is natural. This could explain why some people who claim that they depend on well or borehole water have guinea worm infection.

Table 4:   Distribution of Dracunculiasis in Relation to sexes and Disability in fifteen endemic Communities in Ikwo, Ebonyi State

*Based on both active and ever infected persons.

Table 5: Prevalence and Symptoms of Guinea worm infection in the various age-groups sampled

Of the 4568 persons examined, 2643 (57.9%) agreed to have filtered their water before drinking. Also 615 (13.4%) and 116 (2.5%) of persons who treated their water boiled or sedimented theirs respectively (Table 8). In addition, 1194 (26.13%) claimed that they did not treat their drinking water. 81.1% of persons who could not treat their water were mainly farmers and students/pupils. They believed that water treatment before drinking is a mere waste of time and energy. About 70.2% of the infected persons are farmers and students/pupils (Table 9). A chi-square analysis revealed that the prevalence of dracunculiasis and occupation are related. The monthly and seasonal variation pattern of prevalence showed that March had the highest number of active cases with 105 (16.0%). During the dry season there was a gradual increase in the number of guinea worm active cases starting from 48 (7.5%) recorded by September to 105 (16.4%) recorded in March. By the month of April 40 (6.2%) active cases were recorded. There was a gradual decrease in the number of active cases running through May down to August when the least number of cases 6 (0.9%) were recorded (Table 10).

Table 6:  Prevalence of dracunculiasis in relation to predilection sites

DISCUSSION

Ebonyi State had hitherto been known as the most endemic state for dracunculiasis in Nigeria (Hopkins 1998). The endemicity in the area could be related to the topography as well as the existence of several large ponds in the area which are not found in other local Government areas. Associated with these large water bodies is the problem of abate treatment. Unlike in other areas where smaller ponds exist, abate treatment is feasible and the water bodies are technically not easy to treat than large water bodies which are not treatable. Consequently, such large water bodies have continued to be breeding sites for Cyclops vectors in the area. The field officers working in the area could only treat the contact points in the water bodies where the people fetch water. However, this is not very effective as the entire volume of water is not well covered. This also shows that pond treatment with the chemical (abate) is a major intervention strategy in the eradication of dracunculiasis. Similar observations have been made by (Nwosu et al 1982; Nwobi et al 1996).

Table 7:  Prevalence of dracunculiasis in relation to

source of water supply

There was significant variation in the various communities. These may be attributed to two major factors. Firstly Ndufu Amagu and Ndufu Echara where highest prevalences were recorded had intercommunity clashes in the last three years. This clash disrupted all the guinea worm eradication efforts in the area. Furthermore, due to the intercommunity problems, the Village Based Health Worker (VBHWs) in the area either stopped intervention activities or backed out of the programme and this consequently led to high prevalence rates in these areas. For any meaningful attempt at control/eradication of dracunculiasis in such communities therefore, there must be Village Based Health Worker covering these communities in terms of case detection, disease management through case containment as well as systematic pond treatment every 28 days. This would eventually aid in the final fight against dracunculiasis eradication in Ebonyi State as it has been the case in other endemic areas (Udonsi, 1987 a, b; Nwoke 1992). Secondly, differences observed in the various communities could as well be related to variations and degree of exposure to the infested source of water supply. This is in line with the reports of Anosike et al (2000). They noted that in communities where the inhabitants are fully exposed to guinea worm infection due to lack of good sources of water and systematic pond treatment that endemicity levels are usually high. Kappus et al (1991) and Nwoke (1992) also subscribed to these observations.

Table 8:  Methods of water treatment in relation to various occupational groups in the communities studied

The disease pattern in the study area showed that it is a long standing infection since over 58% of the population sampled in Ikwo L.G.A had ever been infected at one point or the other. Similar observations have been made in other endemic areas in Nigeria (Onabamiro 1956; Edungbola 1983; 1984; Onwuliri et al 1988-90a & b; Nwoke 1992, Okoye et al 1995). Strikingly, most people in these communities sampled initially do not associate dracunculiasis with water (Anosike 2000). Sequel to this, effective health education talks were organized by the Nigeria guinea worm eradication programme (NIGEP) field managers in Ebonyi State to the endemic rural people, it is interesting to note that presently, most communities in the endemic areas of Ebonyi State are fully aware that dracunculiasis is caused by drinking water from infested ponds (Amadi 2002). Therefore, the provision of safe drinking water and mass mobilization of communities and the adoption of simple health education measures may be necessary to break dracunculiasis, thus eliminating its morbidity and socio-economic consequences (Suleiman and Abdullahi 1988-90 and Udonsi 1987). More males than females were affected because of hired laborers from other communities. The disabilities found to be common amongst guinea worm infected persons are crippling effects which were very high in both female and male patients, while poor maternal attention was only found among the females. Disability arising from guinea worm infection is due to swelling effect of the legs as well as painful ulcers due to re-infection and emergence of new worms several months after the first worm emergence. Dracunculiasis has serious economic implications in any guinea worm endemic area since the persons mostly affected are those young adults that belong to the productive age group. This is in agreement with those of Nwosu et al (1982), Edungbola (1983; 1984) Onwuliri et al (1998-90a & b) Anosike et al (2000). Majority of the infected persons had fever especially prior to the blisters. This is usually followed by severe pain, more so when such worm is nearer to the ankle or joints. However, several mild clinical symptoms such as fever, nausea, loss of appetite, vomiting, diarrhoea, severe pain and wounds are of epidemiological importance.

Sources of water supply and use in Ikwo L.G.A include seasonal streams, wells, seasonal stagnant ponds and few peremial ponds as well as some borehole which could not serve the whole communities. All the people depending on these several types of water supply had guinea worm infections. A few subjects that depend on boreholes had infections. Actually, these people did not contact such infections from the boreholes but rather confirmed that they drank from untreated pond water the previous year before the boreholes were installed. A greater proportion of persons who depended on pond water had infections. This observation is expected. Infected Cyclopes are found in the ponds and when taken without filtering or boiling results in guinea worm infection. A few others who depended on streams were also infected. During the dry season months, such seasonal streams stop flowing thereby creating stagnant ponds along the water courses. Communities around such areas depend on these water bodies for drinking, washing and other domestic chores. This could explain why 14% of the persons who depend on these water sources were infected.

Boreholes and wells had no infected Cyclops while ponds harbour infected Cyclops. Conversely, observations in the field showed that due to mixing of borehole water and well water together with the untreated pond water mainly to have pond water taste. They believe that pond water is cool and thick in the mouth. To some others, they still depend on pond water regardless of the presence of boreholes in their communities. This could explain why those who claim to depend on boreholes/wells water still have guinea worm disease. This therefore, calls for constant health education of these rural population to wipe out this belief and ignorance. Currently, the staff of Nigeria Guinea worm Eradication Programme (NIGEP), have mounted a campaign towards erasing these local beliefs as was done in parts of Western Nigeria (Brieger et al 1991; Nwoke 1992). Therefore, the prevalence of guinea worm infection in relation to source of drinking water supply showed that the disease in the study area depends on the sources of water supply. This actually agrees with the earlier report by Bourne (1986) that guinea worm is the only disease exclusively transmitted by drinking contaminated water therefore can be eradicated simply by providing safe water sources. Different methods of water treatment exist in the rural communities of Ebonyi State and these were related to various occupations of the endemic communities. They are aware that the only way to prevent guinea worm infection is by water treatment. Therefore, they boil, sediment or filter their water. However, there are still some others who find it very difficult to use any of these method to treat their water. They generally believe that treatment of water by boiling for example is waste of time, energy and financial resources. In this study, 26.1% of the total sampled population agreed that they did not treat their water before drinking. These were mainly farmers and traders. The farmers after farming drink untreated pond water due to thirst while traders who move from one market to another buying and selling food stuff rarely treat their drinking water. They buy pond water sold in the market places and drink them without proper treatment. Infection is more on people who find it very difficult to treat their water before use even when filters are given free of charge courtesy of Global 2000, Carter Center and NIGEP staff working in the area. However, with proper health education talks, there could be behavioural change by the people. Nwoke (1992) has proposed the use of consistent and persistent health education to solve this cultural and behavioural inclinations.

Table 10: Monthly and Seasonal Variation patterns of Guinea worm cases in Ikwo LGA

There is seasonal variation in the prevalence of dracunculiasis in the area. The transmission period in that area was found to be the months of dry season. During the dry season periods the volume of water in the ponds is reduced and the Cyclops density in the water bodies are more. Consequently, the villagers depend more on the ponds for domestic water use. Furthermore, this period is farming season in the area and farmers depend on pond water while working in their farms. For eradication purposes, intervention activities must be instituted in the area before the beginning of dry season. This would help in forecasting the period when materials should be taken to the field.

Finally, guinea worm disease is endemic in Ikwo area of Ebonyi State Nigeria and the goal of control and final eradication of the disease in the entire state is especially important now the almost all West African countries and the entire world at large are calling for the complete eradication of the disease. The Federal, state and local government authorities in collaboration with other NGOs have launched a final war against the neglected and ancient disease. There is a greater urgency to identify those communities that need filters and abate for the control of infected Cyclops and break in transmission. Provision of clean water in addition to health education will aid in the complete and final eradication of the disease in Ebonyi State Nigeria.

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