24 February 2009

Bad news from Australia: MRSA in water supplies

The Brisbane Courier-Mail reports that scientists in Australia have found MRSA and VRE from hospital sewage in rivers and lakes throughout the state of Queensland, and have been trying for two years to get their provincial government to pay attention.
Secret tests on waste water discharged from 28 Queensland hospitals and clinics revealed the widespread presence of MRSA (Methicillin resistant Staphylococcus aureus) and VRE (Vancomycin resistant Enterococci).
However there was no evidence the potentially lethal organisms had made their way into drinking water.
A Central Queensland University scientist who helped carry out the research told me 97 per cent of hospital sewage discharge lines tested positive for antibiotic resistant bacteria.
He said 70 per cent of hospital discharges tested positive for both MRSA and VRE.
"We got a lot more of those bacteria than we thought possible," he said. ... "Even though they have passed through a treatment process, the bacteria are most likely getting back into natural waterways, dams and ponds used for swimming, boating, fishing and in food production." (Byline: Des Houghton)
The report was presented to the Queensland parliament by a member in 2007, ignored, and presented again last week. (Note for US readers who click through to the story, from my UK childhood: "Tabled," in parliamentary parlance, means "brought forward" or "introduced" — not "postponed" as we would interpret it.)

The wastewater was treated in a sewage plant and then tested — but the usual tests look for enteric pathogens such as E. coli, not for MRSA, so the water passed testing without MRSA's presence being detected.

There have been similar studies in Portugal, South Africa and Nigeria. In the US, MRSA and other resistant bacteria have been found in groundwater and airborne dust, but that has been due to leakage from industrial farming. I'm not aware of anyone doing this sort of study, with organisms escaping from hospitals, in this country. If anyone does know of one, and has a cite, please comment!

1 comment:

daedalus2u said...

This shouldn't be a surprise to anyone. Unless you sterilize any waste that contains antibiotic resistant organisms, some of those organisms are likely to survive.

Unless you remove antibiotics from the waste stream, antibiotic resistant organisms are going to be selected for.

This is a difficult challenge for hospitals, feed lots and waste treatment facilities. It isn’t just hospitals. All patients being treated with antibiotics are likely to shed resistant organisms. The waste has to be treated to remove the antibiotics, kill the resistant bacteria, and then inoculated with non-resistant organisms to metabolize the remaining substrates.