Enumeration and identification of gram negative bacteria present in soil underlying urban waste-sites in southwestern Nigeria.

Samples of soils underlying wastes were collected from four sites representing four demographic regions of a medium sized town in southwestern Nigeria. Standard methods and reference strains of isolated bacteria were employed for identification. Evaluation of the enzymatic and biochemical reactions showed that all isolated and identified microbes were non-fermenting heterotrophic (HTB). For example, Klebsiella pnemuniae may be involved in wound infections, particularly following bowel surgery. Similarly, Pseudomonas aeruginosa can produce serious nosocomial infections if it gains access to the body through wounds or intravenous lines. From the 15 culure plates, 88 colonies with various characteristics were enumerated. They differed in aspect of viscosity and color. The bacterial species were identified by percent positive reactions while oxidative and sugar fermentation tests revealed various characteristics among the isolated strains. All of the isolates were negative for citrate utilization, gelatin liquefaction, nitrate reduction, methyl red and Voges Proskaur, motility and hydrogen sulphate production. The quantity of HTB present in an area serves as an index of the general sanitary conditions of that area. The presence of a large number of HTB, in an ecological area may be considered a liability, as it can enhance the spread of diseases and on a larger scale may enable epidemics to arise. Therefore, there is need for control of waste sites by recovery and regular germicidal sanitation.

Occurrence of antibiotic resistant bacteria in waste site of Ede south west Nigeria.

Analysis of antibiotic resistant bacteria from composted waste site soil samples for two seasons were done, using prepared diagnostic test agar and direct sensitivity tests. All major isolated bacteria were subjected to various antibiotics. Concurrent positive and negative tests were simultaneously studied. Results show relatively high resistant and sensitive bacteria in both seasons. In wet seasons, the Bacillus cereus concentrations are considerably reduced than in the dry. In the dry seasons, Bacillus cereus was sensitive to Erythromycin (ERY) and Tetracycline (TET) and slightly resistant to Ampicillin (AMP), Chloramphenicol (CHL), Cloxacillin (CXC) and water (CNT). In the wet season, identified Pseudomonas aeruginosa was moderately resistant to Streptomycin (STR) and Tetracycline and remained resistant to Ampicillin, Cotrimoxazole (COT), Nitrofurantion (NIT) and water (CNT). The implications for human health are discussed.

Microbial pathogens of public health significance in waste dumps and common sites.

Microbial pathogens of public health significance found in waste and common sites were collected from four different dumping sites and assessed for pathogenic agents. The modified methods employed were based on the classical methods and basic principles of the reactions followed by biochemical enzymatic standards described for gram negative non fermenting bacteria. The results have shown presence of bacterial species including Pseudomonas, Mirococcus, Actinomyces, Neisseria, Bacillus and Klebsiella. These pathogens can infect wounds and cause sepsis and mortality and can even occur with such organisms to cause secondary infection. These groups of organisms are almost impossible to control since they are ubitiquous. Public health may be ensured from pathogenic agents at waste sites by prompt removal of waste and proper management (mechanical sorting and excavating) methods.