The Presence Of Amoeba Resistant Bacteria In Water Distribution Systems. Phase 1: Development And Validation Of Methods

D Bartie

NIOH, Tshwane University of Technology, Tennessee Technical University (USA), University of Lausanne (Switzerland)

Project Summary:

Workers in the mining and other industries are exposed to micro-organisms transmitted through water distribution systems, either through inhalation of aerosols or by direct contact or ingestion. High and/or continued exposure to these organisms increases their risk of respiratory disease, especially when immuno-compromised. This has a severe impact on their ability to work and earn an income to support themselves and their families.

Given the high incidence of TB and HIV in South Africa, with the resulting high number of immuno-compromised workers, the risk of infection with all the above ARB (Table 1), and in particular the respiratory pathogens, is very high. For example, nursing personnel, printers, miners, those working with water-based cutting oils, water treatment personnel, maintenance personnel of water distribution systems, patients in clinics and hospitals (especially those on ventilators) and workers in air-conditioned offices are at high risk.

Although some studies were done on Legionella, Chlamydia pneumoniae and environmental Mycobacteria in South Africa, their survival within FLA has not been studied yet; however there are many international publications that deal with the importance of these organisms in water distribution systems. This is a serious shortcoming as this intracellular existence impacts on the distribution of the organisms to vulnerable hosts, and on the water treatment industry, due to the resistance of amoebal cysts to biocides.

There needs to be baseline information on the prevalence of these organisms in South African water distribution systems. Methods for providing this information need to be set up and validated for future use. Collaboration with local as well as international partners will greatly assist with this process.

The aim of the proposed study is to reduce the risk of respiratory disease in workers in the mining and/or industrial settings and the risk of recontamination of water distribution systems after treatment. To achieve this, the presence of intra-amoebal bacteria of the genera Legionella, LLAP, Mycobacteria, Chlamydia and Parachlamydia in water and biofilm samples will be studied and during later phases of the study, related to antibody levels to the most prevalent ARBs in workers.

Contact Person:

Dr. D. Bartie (