Impact/Purpose:

1. Evaluate the efficacy of QPCR technology for detecting low level microbiological contaminants in water supplies

2. Provide additional data on the range of pathogenic or potentially pathogenic species of fungi in community distribution system and hospital water samples.

Description:

The rate of systemic fungal infections in humans has shown a dramatic increase since 1980. Fungal infections are difficult to treat and fungal infection account for a significant proportion of all fatal hospital acquired (nosocomial) infections in the United States. Pathogenic species of Candida and Aspergillus are the most common agents, however, species of other groups such as Fusarium, and the Zygomycetes, to name a few, are also emerging as significant agents. It is important, especially for susceptible individuals, to prevent exposure to these species. Several of thee species are under consideration for inclusion in future Contaminant Candidate Lists.

Aspergillus fumigatus causes about 40% of fatal nosocomial infections. Research at the Arkansas Medical Center demonstrated that the source of these infections can be from the potable water coming into the patients room, especially from showers. The fatality rate from these infections is between 75 and 90% (depending on the study) because the medical community lacks adequate drugs to control systemic fungal infections. Studies on the occurrence and control of A. fumigatus in potable water are necessary, especially in facilities treating the immunocompromised, who are especially susceptible. These studies should also include three other pathogenic Aspergillus species flavus, niger, and terreus.

The incidence of candidemia is about 8 per 100,000 in the US but with infants < 1 year old, the rate is 75 per 100,000. Systemic candidemia infections have about a 50% mortality rate. About 75% of denture wearers develop oral candidiasis. Oropharyngeal candidiasis occurs in more than 80% of all patients during the course of human immunodeficiency infections. Because of the tremendous use of the azole anti-fungal drugs, resistance is developing in C. albicans and related pathogenic species of Candida. Studies are necessary to evaluate the levels of azole resistant C. albicans in the water supply and evaluate the water supplies contribution to infections.

A coordinated program would be developed to obtain and test samples of water from homes, hospitals, and schools and test these for pathogenic fungi using QPCR.

Record Details:

Record Type:PROJECT

Start Date:10/01/2000

Projected Completion Date:09/01/2006

OMB Category:Other

Record ID: 18344

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Project Information:

Progress :TaqMan specific probes and primers have been developed for pathogenic Fusarium, Candida, Aspergillus and Zygomycete species. Rapid methods have been developed for extraction of fungal DNA from surface waters and distribution system water filtrates.

Studies have been undertaken in collaboration with the Shriner's Hospital in Cincinnati to quantify fungi in the water supply.

A study has also begun in collaboration with the Veterans Administration Hospital in Pittsburgh. Approximately 25 samples from water sources in homes and hospitals have been collected and are being analyzed by QPCR.



Relevance :The CCL Microbiology Planning Committee is currently considering the inclusion of fungi on the Preliminary CCL (PCCL) list. In preparation for this inclusion, it is critical to gain a better measure of exposure by determining the range of fungal species that occur in the drinking water and distribution system waters. This study will evaluate the efficacy of QPCR technology for detecting low level microbiological contaminants in water supplies and provide additional data on the range and estimates of numbers of pathogenic or potentially pathogenic species of fungi in community distribution system and hospital water samples. This information will assist the Office of Water in deliberations over whether these organisms should be included in up-coming CCLs and whether QPCR is an acceptable technology for monitoring drinking water supplies for these and other organisms.

Clients :Office of Water

Research Component :M/DBP (MICROBIAL)

Risk Paradigm :EXPOSURE

Progress :TaqMan specific probes and primers have been developed for pathogenic Fusarium, Candida, Aspergillus and Zygomycete species. Rapid methods have been developed for extraction of fungal DNA from surface waters and distribution system water filtrates.

Studies have been undertaken in collaboration with the Shriner's Hospital in Cincinnati to quantify fungi in the water supply.

A study has also begun in collaboration with the Veterans Administration Hospital in Pittsburgh. Approximately 25 samples from water sources in homes and hospitals have been collected and are being analyzed by QPCR.



Relevance :The CCL Microbiology Planning Committee is currently considering the inclusion of fungi on the Preliminary CCL (PCCL) list. In preparation for this inclusion, it is critical to gain a better measure of exposure by determining the range of fungal species that occur in the drinking water and distribution system waters. This study will evaluate the efficacy of QPCR technology for detecting low level microbiological contaminants in water supplies and provide additional data on the range and estimates of numbers of pathogenic or potentially pathogenic species of fungi in community distribution system and hospital water samples. This information will assist the Office of Water in deliberations over whether these organisms should be included in up-coming CCLs and whether QPCR is an acceptable technology for monitoring drinking water supplies for these and other organisms.

Clients :Office of Water

Research Component :CCL (MICROBIAL)

Risk Paradigm :EXPOSURE

Project IDs:

ID Code :EX.M.21

Project type :ORD-DW Plan

ID Code :9417

Project type :OMIS