Water quality at the source and incidence of water borne diseases in rural households of South India

Background: The relation of water quality indicators and water borne diseases (WBD) is not properly studied in tropical countries like India. Most of the studies done were cross sectional which reported only point prevalence. This tends to under-estimate and is not adequate to explain the relation. In this context to assess the incidence of water born diseases in relation to household drinking water quality, a longitudinal prospective study was conducted.Methods: The study was conducted in a South Indian state, in a rural area among the members of 300 households by weekly data collection for one year. Water samples were collected and analysis was done thrice corresponding to the climate. Bacterial quality indicators - Total coliform count (TCC), Faecal coliform count (FCC) and E. coli were estimated. The data were processed and analyzed.Results: From 300 households, total 1459 persons were enrolled. During the 12 months period, 72 episodes of WBDs were recorded with incidence rate of 49/1000 person years. Proportional morbidity due to WBD was 11.9%. The WBD reported were ADD, dysentery and hepatitis A. Up to 30% water sources contained E. coli in summer and winter samples and more than 60% in rainy samples. Faecal coliform count was >10 MPN/100 ml in all the seasons in more than 60% water sourcesConclusions: Most of the main water source wells were contaminated. Contamination was more in rainy season. Incidence of WBD has no correlation with water quality indicators in all the seasons (p≥0.05).

Groundwater Quality Evaluation in Mando and Rigasa Areas, Kaduna, Northwestern Nigeria

The quality of groundwater from twenty (20) hand-dug wells around the Mando and Rigasa areas, Northwestern Nigeria was evaluated in this study. Physico-chemical parameters like pH, EC, TDS, temperature, Na+, Ca2+, K+, Mg2+, Fe2+, Cl-, HCO3 -, NO3 -, SO4 2- and faecal coliform count were analysed. The degree of compliance of the various parameters with international guidelines for drinking water quality were determined and the groundwater classified. Comparison of the results of physico-chemical analysis with the NSDWQ and WHO guidelines revealed that most of the parameters in the groundwater had 100 % compliance except for pH, Mg2+, NO3 -, K+ and Fe2+ with percentage compliance of 80, 90, 75, 70 and 40, respectively. This indicates that some of the groundwater samples are not suitable for drinking purpose. Groundwater quality map based on the Water Quality Index values for the various groundwater sample showed that most parts of the study area have excellent groundwater quality. The faecal coliform bacteria count ranged from 0 CFU/100 ml to too numerous to count. Only two (2) groundwater samples (10%) complied with the 0 CFU/100 ml guidelines of the NSDWQ and WHO, while the rest eighteen (18) groundwater samples (90 %) have faecal coliform bacteria count above the recommended value. Most of the groundwater samples are not suitable for drinking based on the faecal coliform count. The groundwater samples are suitable for agricultural purposes based on the SAR, RSC and PI classifications. The groundwater in the study area is dominated by Na-Cl and CaHCO3- type facies water.

Bacteriological and heavy metal status of water and fish samples from Jebba Lake – Nigeria

Quantitative and qualitative analysis of bacterial isolates in water and fish samples (Oreochromis niloticus and Clarias gariepinus) from Jebba Lake were carried out using primary isolation media and microbact identification kits. The concentration of heavy metals, Lead (Pb), Copper (Cu), Cadmium (Cd), Chromium (Cr) and Arsenic (As) were determined using Atomic Absorption Spectrophotometer (AAS). Samples were collected from five (5) different stations. Station Jl.1 and Jl.2 are located at the upper course of the lake and were characterized by high human activities (washing, bathing, mining and animal husbandry operations) especially in sample station Jl.2. Sample station Jl.3 has low human activities, however it has a tributary with high mining activities. Station Jl.4 has high domestic washings but low animal husbandry operation and low mining activities. Station Jl.5 has low domestic washings, low animal husbandry operation and low mining activities. Mean faecal coliform count of sample station Jl.1 (580.83 CFU/100ml) and station Jl.2 (700.83 CFU/100ml) were above maximum permissible limit for Federal Environmental Protection Agency (FEPA). Faecal coliform count of sample stations Jl.3, Jl.4 and Jl.5 were below maximum permissible limit. Maximum faecal coliform count during the wet season was 1600.00 CFU/100ml, while the maximum count during the dry season was 920.00 CFU/100ml. Bacterial species such as Aeromonas caviae, Aeromonas hydrophila, Pseudomonas fluorescens – 25, Escherichia coli, Moraxella species, Mannheimia (pasturella) haemolytica, Pseudomonas aeruginosa, Pseudomonas fluorescens – 35, Escherichia hermannii were found in water samples and species such as Vibrio alginolyticus, Moraxella species, Escherichia hermannii, Vibrio parahaemolyticus, Aeromonas hydrophila were isolated from fish intestines and gills. Concentration of Cu, Cr and As in water was observed to be within permissible limit but the concentration of Pb and Cd were above tolerable limit. In fish organs, the concentration of heavy metals were within permissible limit except that of Pb and As in Oreochromis niloticus fish intestines (ONFI) (0.38±0.00 and 0.03±0.00 respectively) and Clarias gariepinus fish intestines (CGFI) (0.40±0.00 and 0.03±0.01 respectively) which were above maximum permissible limit by standard organizations. Key words: Jebba Lake, water, fish, Oreochromis niloticus, Clarias gariepinus, bacteria, heavy metals

Bacteriological Quality of Beef and Hygiene Practices of Food Handlers in Butcheries in Kasama District, Zambia

The most common health risk associated with consumption of beef is microbial contamination, therefore the study was aimed to assess the level of bacterial contamination of beef and evaluate the hygienic practices in butcheries in Kasama district. Beef samples were collected from participating butcheries and a structured questionnaire was also administered to the food handlers.Microbiological quality of the beef samples was determined by Aerobic Plate Count (APC), Faecal Coliform Count (FCC) and bacterial isolation such as Salmonella spp and Staphylococcus aureus. The APC results revealed 40.7% of the butcheries sold meat in good bacterial condition (<4 Log10 cfu/g) while 40.7% and 18.5% were critical (4-5 Log10 cfu/g) and non-acceptable conditions (>5 Log10 cfu/g), respectively. The FCC revealed that 74.1% of the butcheries sold meat in good bacterial conditions (<2 Log10 cfu/g), while 14.8% and 11.1% were critical (2-3 Log10 cfu/g) and non-acceptable conditions (>3 Log10 cfu/g), respectively. Staphylococcus aureus was isolated from 37% of the butcheries, none of the outlets recorded Salmonella spp.Overall, the microbial quality of most (74.1%) of the market ready beef in Kasama district was acceptable for human consumption. Therefore, regular bacteriological monitoring and maintaining hygiene in the sales outlets and distribution chain is mandatory.

Bacteriological Examination of Drinking Water from Different Sources in Sokoto State Nigeria

A total of 50 water samples comprising; 20 well water, 15 sachet water, 10 borehole water and 5 river water samples, were obtained from Wamakko, Dange-shuni and Wurno local government areas in Sokoto Central, Sokoto West and Sokoto East, Nigeria respectively between March and May 2015. They were analyzed using membrane filtration and pour plate techniques for faecal coliforms count and total coliform count respectively. The total coliform count for all the sources ranged between 0 and 3.28 × 102 with a total mean of 1.11 × 10,2 that of faecal coliform count was found to range between 0 and 92 with a mean total count of 12.58. Among the bacteria isolated and identified, Escherichia coli had the highest total prevalence of 233 (40.31%) and occurring in all the water samples. Klebsiella spp had 99 (17.13%) occurring in all the sources, Salmonella spp 43 (7.44%) occurring in all the sources except for borehole, Pseudomonas species 88 (15.22%) occurring in all the sources, Staphylococcus aureus with 115 (19.90%) occurring in all the sources except for borehole. However, the pHs for all the samples were found to be within the range of 6.51 to 8.0 which are within WHO acceptable range of 6.0 to 8.5. From this study, it is obvious that the water sources from the areas under study are bacteriologically unfit for drinking purposes. These samples with high total coliform count are of concern and calls for urgent and stringent measures aimed at ensuring a safer drinking water for the populace.

Spatial Assessment of Public Water Supplies in Densely Populated Areas of Ilorin Metropolis, Kwara State, Nigeri

Water samples collected from public tap supplies at densely populated areas within Ilorin metropolis were analyzed for potability and safety. The study covered a period of twenty-four months. Physicochemical parameters such as pH, turbidity, residual chlorine, colour, suspended solids and total hardness were determined. The pH of the samples ranged from 7.0 - 7.90 while the range for residual chlorine was 0.5 - 10 mg/l. The suspended solids and total hardness ranged from 0.79 - 46.0 mg/l and 7.0 - 34mg/l respectively. Turbidity of the samples ranged from 0 – 5 NTU, while the colour range was 0 - 5 HU and temperature range was 21 - 300C. The results show that only four (20%) of the twenty samples were potable and free from pathogens while Escherichia coli, Klebsiella sp. , Salmonella sp. , Pseudomonas aeruginosa, Shigellla sp. and Enterobacter aerogenes were detected in sixteen (80%) of the samples. The viable total bacterial count ranged between 0.00 – 2.6 x 102 cfu/ml, total coliform count ranged from 0 – 75 MPN/100ml while faecal coliform count ranged from 0.00 – 2.3 x 102 cfu/ml. The presence of coliforms in the samples is indicative of faecal and non-faecal contamination along the supply network, which in some cases could be due to leaching from contaminated environment into corroded pipes along the distribution network used for conveying the treated water that passed through drainage system.

Comparison of methods to analyse imprecise faecal coliform count data from environmental samples

Imprecise values arise when bacterial colonies are too numerous to be counted or when no colonies grow at a specific dilution. Our objective was to show the usefulness of multiple imputation in analysing data containing imprecise values. We also indicate that interval censored regression, which is faster computationally in situations where it applies, can be used, providing similar estimates to imputation. We used bacteriological data from a large epidemiological study in daycare centres to illustrate this method and compared it to a standard method which uses single exact values for the imprecise data. The data consisted of numbers of FC on children's and educators' hands, from sandboxes and from playareas. In general, we found that multiple imputation and interval censored regression provided more conservative intervals than the standard method. The discrepancy in the results highlights both the importance of using a method that best captures the uncertainty in the data and how different conclusions might be drawn. This can be crucial for both researchers and those who are involved in formulating and regulating standards for bacteriological contamination.