Koper tegen verspreiding griepvirus.*
Uit een recente Engelse studie blijkt dat het gebruik van
koper een verspreiding van een griepvirus kan tegengaan. Nog voordat de studie
af is zijn de resultaten al zo zeker dat ze nu al naar buiten gebracht worden.
In de studie wordt gebruikt gemaakt van het H1N1 griepvirus. Daarvan worden 2
miljoen eenheden zowel op roestvast staal als op een zuivere koperplaat
gelegd. Telkens wordt gekeken na 6 uur en 24 uur hoeveel daarvan nog in leven
zijn. Op roestvast staal (RVS oftewel inox) is dat na 6 uur 1
miljoen en na 24 uur nog steeds 500.000 . Daarentegen op een koperen plaat
is dat na 1 uur 500.000 en na 6 uur is 99,99% dood oftewel er leven er slechts
nog maar 500 van de 2 miljoen. De onderzoeker professor Keevil vermeld daarbij
nog dat het H5N1 virus nagenoeg gelijk is en dat de resultaten nauwelijks enig
verschil zullen laten zien. Het advies is dan ook op plaatsen waar virussen
zich gemakkelijk willen verspreiden het materiaal van zuiver koper of
legeringen met veel koper, zoals bijv. brons, te gebruiken.
Copper could help prevent the spread of flu infections. Recent research at the University of
Southampton shows that the Influenza A virus is virtually eradicated within
six hours on copper surfaces. Influenza A viruses cause seasonal infections
resulting in around 12,000 deaths a year in the UK1. The influenza A family of
viruses includes the avian flu strain.
Professor Bill Keevil and Dr Jonathan Noyce, microbiology researchers at the
University's School of Biological Sciences, detail the findings in a study
being prepared for submission for peer-reviewed publication later this year.
Professor Keevil, who heads up the School's Microbiology research group,
explained: ‘The findings are so pertinent to the current concerns about
containing a potential outbreak of the avian flu strain, that we felt it
important to provide some of the preliminary results at this time.'
The Southampton researchers placed 2 million plaque-forming units of Influenza
A (H1N1) on coupons of C11000 copper (common, pure copper sheet metal) and on
S30400 (common stainless steel) at room temperature and then came back
periodically to determine the survival rates of the samples. On the stainless
steel surface, the pathogen declined to 1 million after six hours and to
500,000 after 24 hours. Meanwhile, the copper surface achieved a reduction to
500,000 after only one hour and inactivated all but 500 - a 99.99% reduction -
after just six hours.
In the research, Professor Keevil notes that the H1N1 strain tested is nearly
identical to the H5N1 (avian) strain and that the effectiveness of copper's
antimicrobial properties should be nearly identical as well. He explains that,
while vaccines stimulate host antibodies to target specific exposed cell
surface structures (epitopes), copper's antimicrobial action probably attacks
the overall structure of the virus and therefore has a broad-spectrum effect.
These results are ‘consistent with the demonstrated antimicrobial effects of
copper cited in published studies on E. coli O157:H7, Methicillin-Resistant
Staphylococcus aureus (the superbug, MRSA) and Listeria,' said Professor
Keevil, adding that similar antimicrobial efficacy may be achieved by the
infusion of copper ions into fabrics, filters or other materials. However,
such applications may have diminished effectiveness over time, because the
amount of copper in such materials is much less than in solid copper alloys.
Suggesting it would be worthwhile to consider using uncoated copper or
high-copper alloys, such as many brasses and bronzes, for common-touch
surfaces to help minimise cross-contamination, Professor Keevil said: ‘Door
knobs and handles, push plates, countertops, sinks and other
frequently-touched hardware in healthcare and other public facilities are
prime candidates for use of copper alloys to help control the spread of
infection.'
The Southampton research was sponsored by the Copper Development Association
(CDA) in the USA and the International Copper Association.
1. Improving preparedness for possible flu pandemic, Department of Health
press release 0083, 2005.
2. The University of Southampton is one of the UK's top 10 research
universities, with a global reputation for excellence in both teaching and
research. With first-rate opportunities and facilities across a wide range of
subjects in science and engineering, health, arts and humanities, the
University has around 20,000 students and 5000 staff at its campuses in
Southampton and Winchester.
Its annual turnover is in the region of £274 million.
Southampton is recognised internationally for its leading-edge research in
engineering, science, computer science and medicine, and for its strong
enterprise agenda. It is home to world-leading research centres, including the
National Oceanography Centre, Southampton; the Institute of Sound and
Vibration Research; the Optoelectronics Research Centre; the Textile
Conservation Centre; the Centre for the Developmental Origins of Health and
Disease; and the Mountbatten Centre for International Studies.
3. The Copper Development Association is the information, education, market
and technical development arm of the copper, brass and bronze industries in
the USA.
(Februari 2006)