Indigenous plant based coagulants/disinfectants and sand filter media for surface water treatment in Bamenda, Cameroon

An Evaluation of plant- based coagulants and disinfectant-sand filter  medium for surface water treatment in Bamenda, Cameroon using  bacterial analyses and turbidity were carried out. 100L of very turbid surface water (Turbidity approx. 500NTU) was pretreated with 100 seeds of Moringa oleifera, and further filtered through a sand filter drum (120 L carrying capacity) made of fine, coarse sand, charcoal and gravel. The mean total heterotrophic bacterial counts, Escherichia coli, coliform, pseudomonas and yeast counts, as well as turbidity of untreated surface water significantly reduced by 85 to 95%. The results suggested that the mean values of the same parameters for sand filtered pond water alone was significantly lower than the corresponding mean values obtained for plant coagulant treated surface water. The findings from this study  demonstrates strongly that a biocoagulant sand filter media (plant based coagulant-sand filter drum) could be applied to treat contaminated surface water, rendering it free from solids and pathogens.Key words: Plant, coagulants, indigenous, surface, water, treatment, microbes, Cameroon

A biocoagulant slow sand filtration for disinfection of Toxoplasma gondii oocysts from Mezam River in Bamenda, Cameroon

An integrated low-tech biocoagulant-sand filter drum for disinfection of oocysts of Toxoplasma gondii targeted for developing countries was evaluated. Dirty and turbid water (130.3 NTU) from Mezam River and leachates from dump sites and stagnant water in Bamenda, Cameroon, was analyzed microscopically after centrifugation for oocyst of T. gondii. Leachates from dump sites and stagnant water in Bamenda city had a very high concentration of oocyst of T. gondii too numerous to count per 10 ml while the major Mezam River had 50 oocysts per 10 ml. Considering that is widely used for various domestic chores; filtration disinfection of T. gondii was considered. A bench scale disinfection of oocysts of T. gondii with 0.2 g of powdered Moringa oleifera seeds per 10 ml of contaminated water from Mezam River showed a reduction of 50 oocysts per 10 ml to 10 oocysts in 15 min retention time. To optimize this, a pilot scale up was carried out using 120 L (120,000 ml) of water from Mezam River pretreated with 2400 g of powdered M. oleifera seeds for 15 min retention time and filtered through a sand filter drum made of fine sand, coarse sand, charcoal and gravel for 1 h filtration time. The total mean values of oocysts counts for 120 L of water to be filtered were 600,000 per 120,000 ml. The oocysts counts reduced to 10,000 after pretreatment with 2400 g of powdered seeds of M. oleifera and after a final filtration through a sand filter drum, no oocysts of T gondii was detected in the final treated water. The findings from this study suggests strongly that the application of  natural  coagulants and sand filtration systems could serve a simple low cost disinfection for oocysts of T gondii  from water systems in resource limited countries. Key words: Toxoplasma gondii, oocysts, disinfection, water, biocoagulant, moringa, turbidity, sand filter, drum, Cameroon

SPATIAL DISTRIBUTION AND HABITAT CHARACTERIZATION OF MOSQUITO LARVAE IN BAMENDA, CAMEROON.

Spartial distribution and habitat characteristics of mosquito larval habitats in Bamenda were determined. A cross sectional study was done in which 125 mosquito larval habitats were surveyed from August 2014 to October 2016. Spatial distribution and characteristics of larval habitats for different mosquito genera and for different area were compared. Results obtained showed a highly significant difference (p <0.05) in the distribution of the different mosquito larval genera with Culex larvae predominating (78.05%). Majority of the habitats were found in areas of high density housing (52.8%). The different mosquito types demonstrated distinct preferences for larval habitats. Culex and Aedes mosquitos had higher preference for artificial habitats with used tyres predominating (55%), while Anopheline had higher preference for natural habitats. There was a significant relationship between presence of larval habitats and distance to the nearest household, dissolved oxygen, optical density and elevation (p<0.05). Conclusively the present study brings out some significant relationship between larval habitats and some physicochemical and enviromental factors that are vital for effective larval source mangement within Bamenda