Viruses can be made to treat bacterial diseases. Ths targetted treatment will spare useful bacteria.
K.S.Parthasarathy
Public release date: 2-Sep-2007
Contact: Lucy Goodchild
l.goodchild@sgm.ac.uk
44-011-898-81843
Society for General Microbiology
New viruses to treat bacterial diseases -- 'My enemies' enemy is my friend'
Viruses found in the River Cam in Cambridge, famous as a haunt of students in their punts on long, lazy summer days, could become the next generation of antibiotics, according to scientists speaking today (Monday 3 September 2007) at the Society for General Microbiology’s 161st Meeting at the University of Edinburgh, UK, which runs from 3-6 September 2007.
With antibiotics now over-prescribed for treatments of bacterial infections, and patients failing to complete their courses of treatment properly, many bacteria are able to pick up an entire array of antibiotic resistance genes easily by swapping genetic material with each other.
MRSA – the multiple drug resistant strain of Staphylococcus aureus - and newly emerging strains of the superbug Clostridium difficile have forced medical researchers to realise that an entirely different approach is required to combat these bacteria.
“By using a virus that only attacks bacteria, called a phage – and some phages only attack specific types of bacteria – we can treat infections by targeting the exact strain of bacteria causing the disease”, says Ana Toribio from the Wellcome Trust Sanger Institute in Hinxton, Cambridgeshire, UK. “This is much more targeted than conventional antibiotic therapy”.
The scientists used a close relative of Escherichia coli, the bacterium that commonly causes food poisoning and gastrointestinal infections in humans, called Citrobacter rodentium, which has exactly the same gastrointestinal effects in mice. They were able to treat the infected mice with a cocktail of phages obtained from the River Cam that target C. rodentium. At present they are optimizing the selection of the viruses by DNA analysis to utilise phage with different profiles.
“Using phages rather than traditional broad-spectrum antibiotics, which essentially try to kill all bacteria they come across, is much better because they do not upset the normal microbial balance in the body”, says Dr Derek Pickard from the Wellcome Trust Sanger Institute. “We all need good bacteria to help us fight off infections, to digest our food and provide us with essential nutrients, and conventional antibiotics can kill these too, while they are fighting the disease-causing bacteria”
Phage based treatment has been largely ignored until recently in Western Europe and the USA. The main human clinical reports have come from Eastern Europe, particularly the Tbilisi Bacteriophage Institute in Georgia where bacteriophages are used for successful treatment of infections such as diabetic ulcers and wounds. More studies are planned along western clinical trial lines with all the standards required.
“The more we can develop the treatment and understand the obstacles encountered in using this method to treat gut infections, the more likely we are to maximise its chance of success in the long term”, says Ana Toribio. “We have found that using a variety of phages to treat one disease has many benefits over just using one phage type to attack a dangerous strain of bacteria, overcoming any potential resistance to the phage from bacterial mutations”.
“This brings us back to the problem we are trying to address in the first place. If anything, conventional antibiotic treatment has led to MRSA and other superbug infections becoming not only more prevalent but also more infectious and dangerous. Bacteriophage therapy offers an alternative that needs to be taken seriously in Western Europe”, says Derek Pickard.
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Notes to News Editors:
For further information contact Dr Derek Pickard, Wellcome Trust Genome Campus, The Wellcome Trust Sanger Institute, Cambridgeshire, tel: 01223 495391, fax: 01223 494919, email: djp@sanger.ac.uk
Ms Toribio is presenting the poster ‘Citrobacter rodentium phage: Characterization and screening for phage therapy applications’ at 1520 on Monday 03 September 2007 in the Environmental Microbiology Group session of the 161st Meeting of the Society for General Microbiology at the University of Edinburgh, 03 - 06 September 2007.
For press enquiries during the meeting please contact the SGM desk on +44 (0) 131 650 4581 or mobile telephone +44 (0) 7824 88 30 10
For enquiries prior to the meeting contact Lucy Goodchild at the SGM office, tel: +44 (0) 118 988 1843, fax: +44 (0) 118 988 5656, email: l.goodchild@sgm.ac.uk
Full programme details of this meeting can be found on the Society's website at: http://www.sgm.ac.uk/meetings/MTGPAGES/Edinburgh07.cfm. Hard copies are available on request from the SGM.
The Society for General Microbiology is the largest microbiology society in Europe, and has over 5,500 members worldwide. The Society provides a common meeting ground for scientists working in research and in fields with applications in microbiology including medicine, veterinary medicine, pharmaceuticals, industry, agriculture, food, the environment and education.
The SGM represents the science and profession of microbiology to government, the media and the general public; supporting microbiology education at all levels; and encouraging careers in microbiology.
1 comment:
While I appreciate all publicity about phage therapy, I believe that we are being seduced into reinventing the wheel - considering that there appear to be references in the scriptures of at least 3 religions, Hinduism, Islam and the old testament of the Bible, that can be explained on the basis of phage therapy it is time to start using this treatment option when antibiotics fail. The item below gives enough references for people to study the subject further:
Choosing to let patients with superbug infections die rather than phage them!!!!
It is my humble opinion that the antibiotic-resistance superbug crisis is the mother of all regulatory-scientific-environmental misadventures; however, the absurdity of the superbug crisis consists of the fact that it can be demonstrated that we had technology, namely bacteriophage therapy, long before we created the antibiotic-resistance superbug crisis through massive abuse of antibiotics and other antimicrobials. Additionally many politicians, bureaucrats, scientists and members of the public health community are or should be well informed about phage therapy which can cure many superbug infections. In spite of a voluminous literature attesting to the scientific validity, safety and medical effectiveness of phage therapy (see http://www.phage.org and find phage therapy references), there are still phage therapy deniers who would resist the careful deployment of these weapons of mass-destruction for specific pathogens in the war with superbugs.
What is Phage Therapy? Prior to the discovery and widespread use of antibiotics, bacterial infections were treated worldwide by the administration of bacteriophages. Bacteriophages or phages are highly specific viruses that invade bacterial cells and, in the case of lytic phages, disrupt bacterial metabolism and cause the bacterium to die. Interestingly it was the French-Canadian microbiologist, Felix d'Herelle, while working at the Institute Pasteur in Paris in 1917 who is credited with discovering and promoting phage therapy. While the use of phage therapy was discontinued in the West soon after the discovery of antibiotics they continued to be utilized in Eastern Europe and today many infections untreatable with antibiotics can be treated in clinics in Georgia (Europe) and Poland. Once one accepts the fact that it requires microscopes to see the world of bacteria and bacteriophages, phage therapy may be compared to any biological control methodology and can conceptually be described as: What a cat is to a mouse the right bacteriophage is to a specific bacterium or superbug. Phage therapy has been going on in nature as a balancing force in the evolution of microbes for a long time. Medical phage therapy is simply the intervention by humans to ensure that the balance is in favour of bacteriophages over susceptible bacterial pathogens! While there is considerable expertise on phage therapy in Canada at the research level, as can be substantiated by googling phage therapy ("pages from Canada" only), medical phage therapy is not currently approved or practised in Canada; however, according to a letter signed by the former federal health minister phage therapy can be made available legally to Canadian patients under the Special Access Program of our Food & Drugs Act! Additionally, there are moral and ethical reasons for making phage therapy available since Canada appears to be a member of The World Medical Association which states: "In the treatment of a patient, where proven prophylactic, diagnostic and
therapeutic methods do not exist or have been ineffective, the physician, with informed consent from the patient, must be free to use unproven or new prophylactic, diagnostic and therapeutic measures, if in the physician's judgement it offers hope of saving life." ( see below for quote source ).
A discussion of phage therapy is currently very timely, not only because too many patients are dying of superbug infections; but also because of the recent release of the Canadian film: Killer Cure: The Amazing Adventures of Bacteriophage and the June 2006 release of the book by Thomas Haeusler entitled, Viruses vs. Superbugs, a solution to the antibiotics crisis? ( see http://www.bacteriophagetherapy.info ) - both are available at Ottawa libraries. Additionally, the record of an excellent questions-and-answers session with Dr. Roger Johnson of the Public Health Agency of Canada can be found at http://meristem.com/topstories/ts06_08.html .
Further, the phage therapy file has dramatically changed during the last few months because the US Food and Drug Administration (FDA) has amended the US food additive regulations to provide for the safe use of a bacteriophage preparation on ready-to-eat meat and poultry products as an antimicrobial agent against Listeria monocytogenes (see http://www.fda.gov/OHRMS/DOCKETS/98fr/02f-0316-nfr0001.pdf ). This excellent submission evaluation changes the scientific validity of phage therapy from Eastern European science, which, sadly, too many of us Westerners dismiss with hubris and bias as not credible, to approved and supported by the all-knowing and all-seeing FDA at least for ready-to-eat meats. An enlightening FDA questions-and-answers document can be found at http://www.cfsan.fda.gov/~dms/opabacqa.html .
Superbugs are everybody’s business because superbugs make everybody their business and every North American should study the above references because sooner or later everybody will be faced with an infection or know a relative or friend who will be suffering or dying with one. Withholding such treatment from patients when antibiotics are failing ought to be a crime; however, those who have the money, knowledge and time to travel when faced with an infection where antibiotics are failing may be able to get phage therapy treatment in Georgia ( http://www.phagetherapycenter.com ) or Poland - http://www.aite.wroclaw.pl/phages/phages.html . A record of a trip to Georgia to get phage therapy treatment by UK citizens can be seen at http://www.relax-well.co.uk/news.html .
What is even more surprising and frustrating is that an American company, Phage International Inc., ( http://www.phageinternational.com ) would probably be willing and able to set up a phage therapy clinic in any country if the right regulatory climate existed. A recent article describing how foreigners from many countries are treated at their Phage Therapy Center in Tbilisi, Georgia can be found at http://www.phagetherapycenter.com/doc/sjbizjournal.pdf .
Since January 1, 2000 as many 87,000 Canadians may have died of superbug bacterial infections and there is not even a memorial for them, although some people are starting to wear blue ribbons in memory of superbug victims. Would it not be nice if the Canadian governments, public health officials and media got together and funded the Felix d'Herelle Center for Phage Therapy to provide the phage therapy treatment option for patients when antibiotics fail and we have nothing left to offer them?
P.S.: WORLD MEDICAL ASSOCIATION DECLARATION OF HELSINKI PARAGRAPH 32:
"In the treatment of a patient, where proven prophylactic, diagnostic and
therapeutic methods do not exist or have been ineffective, the physician,
with informed consent from the patient, must be free to use unproven or new
prophylactic, diagnostic and therapeutic measures, if in the physician's
judgement it offers hope of saving life, re-establishing health or
alleviating suffering. Where possible, these measures should be made the
object of research, designed to evaluate their safety and efficacy. In all
cases, new information should be recorded and, where appropriate, published.
The other relevant guidelines of this Declaration should be followed."
FROM: The World Medical Association:
http://www.wma.net/e/policy/b3.htm - and
http://www.aite.wroclaw.pl/phages/phages.html
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