Bed net use and associated factors in a rice farming community in Central Kenya.

BACKGROUND: Use of insecticide-treated nets (ITNs) continues to offer potential strategy for malaria prevention in endemic areas. However their effectiveness, sustainability and massive scale up remain a factor of socio-economic and cultural variables of the local community which are indispensable during design and implementation stages. METHODS: An ethnographic household survey was conducted in four study villages which were purposefully selected to represent socio-economic and geographical diversity. In total, 400 households were randomly selected from the four study villages. Quantitative and qualitative information of the respondents were collected by use of semi-structured questionnaires and focus group discussions. RESULTS: Malaria was reported the most frequently occurring disease in the area (93%) and its aetiology was attributed to other non-biomedical causes like stagnant water (16%), and long rains (13%). Factors which significantly caused variation in bed net use were occupant relationship to household head (chi2 = 105.705; df 14; P = 0.000), Age (chi2 = 74.483; df 14; P = 0.000), village (chi2 = 150.325; df 6; P = 0.000), occupation (chi2 = 7.955; df 3; P = 0.047), gender (chi2 = 4.254; df 1; P = 0.039) and education levels of the household head or spouse (chi2 = 33.622; df 6; P = 0.000). The same variables determined access and conditions of bed nets at household level. Protection against mosquito bite (95%) was the main reason cited for using bed nets in most households while protection against malaria came second (54%). Colour, shape and affordability were some of the key potential factors which determined choice, use and acceptance of bed nets in the study area. CONCLUSION: The study highlights potential social and economic variables important for effective and sustainable implementation of bed nets-related programmes in Sub-Saharan Africa.

Malaria vector control practices in an irrigated rice agro-ecosystem in central Kenya and implications for malaria control.

BACKGROUND: Malaria transmission in most agricultural ecosystems is complex and hence the need for developing a holistic malaria control strategy with adequate consideration of socio-economic factors driving transmission at community level. A cross-sectional household survey was conducted in an irrigated ecosystem with the aim of investigating vector control practices applied and factors affecting their application both at household and community level. METHODS: Four villages representing the socio-economic, demographic and geographical diversity within the study area were purposefully selected. A total of 400 households were randomly sampled from the four study villages. Both semi-structured questionnaires and focus group discussions were used to gather both qualitative and quantitative data. RESULTS: The results showed that malaria was perceived to be a major public health problem in the area and the role of the vector Anopheles mosquitoes in malaria transmission was generally recognized. More than 80% of respondents were aware of the major breeding sites of the vector. Reported personal protection methods applied to prevent mosquito bites included; use of treated bed nets (57%), untreated bed nets (35%), insecticide coils (21%), traditional methods such as burning of cow dung (8%), insecticide sprays (6%), and use of skin repellents (2%). However, 39% of respondents could not apply some of the known vector control methods due to unaffordability (50.5%), side effects (19.9%), perceived lack of effectiveness (16%), and lack of time to apply (2.6%). Lack of time was the main reason (56.3%) reported for non-application of environmental management practices, such as draining of stagnant water (77%) and clearing of vegetations along water canals (67%). CONCLUSION: The study provides relevant information necessary for the management, prevention and control of malaria in irrigated agro-ecosystems, where vectors of malaria are abundant and disease transmission is stable.

Effect of chlorination of drinking-water on water quality and childhood diarrhoea in a village in Pakistan.

To evaluate the importance of public-domain transmission of pathogens in drinking-water, an intervention study was carried out by chlorinating the public water-supply system in a village in Pakistan. The water quality improved and reached a geometric mean of 3 Escherichia coli per 100 mL at the last standpipe of the water-supply system. Drinking-water source used and the occurrence of diarrhoea were monitored on a weekly basis over a six-month period among 144 children aged less than five years in the village. In this group, the children using chlorinated water from the water-supply scheme had a higher risk of diarrhoea than children using groundwater sources, controlled for confounding by season and availability of a toilet and a water-storage facility. The incidence of diarrhoea in the village (7.3 episodes per 10(3) person-days) was not statistically different from that in a neighbouring village where most children used water from a non-chlorinated water-supply system with very poor water quality. In this study area, under non-epidemic conditions, the reduction of faecal bacteria in the public drinking-water supply by chlorination does not seem to be a priority intervention to reduce childhood diarrhoea. However, the study was of limited size and cannot provide conclusive evidence.

Domestic transmission routes of pathogens: the problem of in-house contamination of drinking water during storage in developing countries.

Even if drinking water of poor rural communities is obtained from a 'safe' source, it can become contaminated during storage in the house. To investigate the relative importance of this domestic domain contamination, a 5-week intervention study was conducted. Sixty-seven households in Punjab, Pakistan, were provided with new water storage containers (pitchers): 33 received a traditional wide-necked pitcher normally used in the area and the remaining 34 households received a narrow-necked water storage pitcher, preventing direct hand contact with the water. Results showed that the domestic domain contamination with indicator bacteria is important only when the water source is relatively clean, i.e. contains less than 100 Escherichia coli per 100 ml of water. When the number of E. coli in the water source is above this value, interventions to prevent the domestic contamination would have a minor impact on water quality compared with public domain interventions. Although the bacteriological water quality improved, elimination of direct hand contact with the stored water inside the household could not prevent the occasional occurrence of extreme pollution of the drinking water at its source. This shows that extreme contamination values that are often thought to originate within the domestic domain have to be attributed to the public domain transmission, i.e. filling and washing of the water pitchers. This finding has implications for interventions that aim at the elimination of these extreme contaminations.