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Microorganisms are present on all surfaces, to which they were carried by many direct and indirect methods of transmission. Bacteria and Parasites contaminating office door handles in Nnamdi Azikiwe University were assessed between June and November, 2019. The buildings and the door handles were randomly selected. Sterile swabs moistened in sterile normal saline were used to swab the door handles in a tri-directional manner. The swabs were cultured and subcultured onto nutrient, MacConkey and Salmonella-Shigella agar plates for bacterial growth. The specimens were then examined for parasites using Zinc Sulphate floatation and formol-ether sedimentation techniques. Of the 432 door handles examined, 136 (30.8%) were contaminated. The highest number of contaminated doors were found in Medical Centre 41 (30.1%) and the least in Faculty of Social Sciences Complex 10 (7.4%). E. histolytica 52 (38.2%) was the highest parasite encountered while E. vermicularis 2 (1.5%) was the least. The proportion of infected doors as well as the distribution of different species parasites in the door handles of different complexes examined was significant (P<0.05). Of 432 office door handles examined, 263 (60.9%) yielded bacterial growth. Female hostel 72 (27.4%) had more bacterial contamination while Faculty of Social Sciences 25 (9.5%) had the least. Staphylococcus spp 54 (20.5%) was the highest bacteria isolated, followed by Escherichia 53 (20.2%) while Klebsiella 53 (20.2%) was the least. The distribution of different species of bacteria in the door handles in different complexes was significant (P<0.05). Infectious diseases from microbial contaminated door handles are a potential threat to public health and safety therefore certain measures should be taken such as aggressive and frequent cleaning methods and good hand washing to reduce the incidence of bacterial and parasite transmission and contamination.

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The effects of crude oil pollution on soil physicochemical properties, microflora, and ecotoxicity were evaluated. Soil samples were contaminated with crude oil, and the effects of contamination on the physicochemical parameters, microflora, and growth index of bean (Phaseolus vulgaris) seeds were studied over a 6-month period. The heterotrophic bacteria isolated from the uncontaminated soil were Micrococcus, Klebsiella, Flavobacterium, Bacillus, Pseudomonas, and Serratia species, and the moulds included microbes such as Aspergillus niger, Fusarium, and Mucor sp. Petroleum contamination increased the pH of the soils to alkaline values while increasing the total nitrogen, organic carbon, and phosphorus contents. Electrical conductivity, nitrogen content, and phosphorus content were significantly reduced after petroleum contamination (p ˂ 0.05). The heavy metal contents of the contaminated soils decreased with increasing remediation time. Zinc, total nitrogen, total organic carbon, and electrical conductivity contents were statistically significantly different among samples throughout the bioremediation period (p ˂ 0.05). The ability of isolates to utilise hydrocarbons was highest for Pseudomonas and Bacillus species and lowest for Klebsiella and Serratia species. After a germination period of 12 days, a germination test showed that the bioattenuated polluted soil improved germination of bean seeds. Bioattenuation methods should be used and improved as a means of remediating petroleum-polluted sites because they are cost-effective and environmentally friendly.