Impact of water resources development on health: Ghana Francis Anto (PhD) Navrongo Health Research Centre - GHS

Navrongo Health Research Centre- Ghana Health Service

Map of Ghana showing some water development projects Volta Lake Tono dam Proposed Bui dam

Kassena-Nankana district showing the Tono dam

Health Impact of water resources development Programmes of water resources development and the resultant population movements are known to have worsened the transmission of schistosomiasis in countries like Ghana, Nigeria, Sudan, Brazil and the Philippines (Iarotski and Davis, 1981). This has led to an increase in both prevalence and intensity of infection.

Health Impact of water resources development cont. Water resources development has become increasingly important in African countries including Ghana Although improved hydraulic infrastructure holds potential for: 1.alleviating poverty 2.promoting economic growth 3.improving food security and mitigating floods, adverse health effects may undermine these objectives (Hunter et al. 1993; Jobin 1999; Keiser et al. 2005), if the appropriate measures are not put in place

Impact of the Tono irrigation system on health The largest irrigation system in Ghana (Tono irrigation system-ICOUR) is located in the Kassena-Nankana district of the upper east region The region has about 144 small dams and 70 dug-outs These water development schemes have worsened the schistosomiasis burden of the region (Scott, 1977; Amankwa, et al., 1994; Hunter, 2003) Leading to a prevalence level of about 70% among school- age children living along the Tono irrigation canals (Amankwa, et al., 1994)

Overall infection was 48%, more males (52%) than females (41%) infected p=0.002 Overall infection in in-school children similar to those not in-school

71% swim in canals, 60% wash items in canals, More swimmers (p=0.004) than non-swimmers were infected. More workers on tomato farms (p=0.003) than non workers were infected

Table 1. Malaria transmission intensity in the Kassena-Nankana district Geographical zoneTransmission Intensity Biting rate (bite per man per night ) Irrigated36.7 Non-irrigated lowland5.9 Rocky highland5.2 EIR (Infective bite per year) Irrigated630 Non-irrigated lowland228 Rocky highland360 (Appawu et al, 2004)

Table 2. Malariometric characteristics of children (<5 yrs) surveyed in KND ( ) ParametersGeographical zone Rural irrigated Rural non- irrigated Central more urbanized P-value Overall parasite prevalence 48%56%30%<0.001 Overall bednet use80%23%34%<0.001 Severe anaemia (Hb<6.0g/dL) 1.3%3.5% >0.5 Fever (axillary temperature ≥37.5oC 8.3%9.1%13.3%>0.5 All cause mortality100.5/1000 live births 153.7/1000 live births 95.9/1000 live births <0.05 Malaria specific mortality 26.4/1000 live births 48.4/1000 live births 27.7/1000 live births >0.05

Prevalence of infection was seasonal in rural non-irrigated area (dry=37.7%; wet 72.2%, p<0.001). The prevalence of infection in the rural irrigated (dry=41.3%; wet 55.4%, p>0.05) and central more urbanized (dry=22.6%; wet 34.3%, p>0.05) areas was not seasonal

Bed net was found to protect those who used them from malaria infection (p=0.003)

All cause mortality was highest in the rural non-irrigated area where malaria infection was also highest

Impact of Akosombo dam on health When Ghana gained independence in 1957 from British colonial rule, it was envisioned that the Akosombo dam project was the most economical source of energy needed for the industrialization and modernization of the country This led to an increase in prevalence of schistosomiasis from about 3% in 1961 to about 84% by 1967 in schoolchildren [upstream: Kete Krachi, and Yeji] (Paperna, 1969) And also from about 17% in 1963 to 74.6% in 1981 [downstream: Bator](Wen and Chu 1984)

Bui dam site

Bui dam Having had problems with the supply of adequate electricity from Akosombo dam, for over a year now, the government of Ghana is embarking on building of another hydroelectric dam, the Bui dam. In addition to generating electricity, there will be an irrigation system and A modern city, the Bui city

Ecological changes with dam construction Flow of the river slow down Increased aquatic vegetation Proliferation of water snails Increased schistosomiasis Inundation of forest vegetation Reduction in tsetse Fly population Temporary reduction In incidence of trypanosomiasis Vegetative re-growth Rapid rebound of infestation Favourable habitat for mosquito breeding Increased malaria Prevalence Increased LF Prevalence Creation of ponds Proliferation of cyclops Increase in Prevalence of Guinea worm Reduction in Black Fly population Reduction in Prevalence of River blindness

Some beneficial effects 1.Reduction in incidence of onchocerciasis 2.With the irrigation scheme, there will be improvement in food production in the long term

Current situation at the Bui site I The health and nutritional status of the communities in the Bui project area have been described as poor That malnutrition is pervasive with a high prevalence of infectious diseases including schistosomiasis. There is lack of potable water and inadequate health services and facilities Poor environmental sanitation and housing (Environmental impact assessment report)

Current situation at the Bui site II Similar to the Volta basin, schistosomiasis is prevalent in the Bui project area (ERM report, 2007) There is therefore a very high likelihood that the prevalence and intensity of the disease will rise as a result of the development of the water project

Potential health problems (Bui) According to the EIA report: The creation of the dam will impact significantly on disease incidences in the local region Specifically: Bilharzia Trypanosomiasis Guinea worm Intestinal worms and onchocerciasis. Health impacts may also arise in the long term owing to: the loss of medicinal plants reduced food security arising from lower farm productivity and in-migration of people carrying communicable diseases

Conclusion There is no doubt that water resources development increases the incidence of several tropical diseases 1.Dams in Cameroon (Atangana et al. 1979) 2.Kenya (Oomen 1981; Roggeri 1985) 3.Mali (King 1996) 4.Ethiopia (Lautze et al, 2007) have resulted in an increased malaria burden 5.Ghana (Wen &Chu, 1984) schistosomiasis 6.Ghana (Ampofo and Zuta,1995) Barekese dam

Recommendations Communities closest to the reservoir appear to be the worst affected Large water impoundments in malaria endemic parts of sub-Saharan Africa are likely to increase the force of malaria transmission Appropriate measures need to be put in place to mitigate the impact through informed prevention strategies This requires an integrated approach to water resources development that substantially incorporates health parameters into development plans and encourages on- going collaboration between the water and health sectors

Recommendations 1.Malaria Promotion of ITNs Indoor residual spraying 2.Schistosomiasis Annual chemotherapy (praziquantel) Mollusciciding (baylucide) 3.Lymphatic filariasis Annual ivermectin plus albendazole 4.Guinea worm Potable water Control of cyclps (Abate) 5.Buruli uncer Effective community surveillance

Potential areas of research collaboration Malaria Schistosomiasis Guinea worm Onchocerciasis Lymphatic filariasis Buruli ulcer Socio-economic studies

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