Therapy could stop superbugs on farms, by Pallab Ghosh, BBC News website.
Researchers at Leicester University have identified a range of viruses, called bacteriophages, that can be used to kill common pig infections. The aim is to reduce the risk of antibiotic resistant bacteria emerging on farms that could also infect humans. In the UK, 40% of all antibiotics are used to treat animals - they are the same as those used to treat people.
Phages occur in nature and are the natural enemy of many infectious agents. Each of the many phages is specific to different infectious bugs, homing in on them and injecting the phage's DNA into the bug, thus rendering it harmless. Like all viruses, phages reproduce inside the infectious bug and these new phages then hunt other infections.
Attempts to develop phage treatments have been carried out for more than a century but have mostly proved unreliable. However, researchers have now found more precise ways of isolating phages and assessing their effectiveness.
The research team has identified a range of disease-killing phages, and more importantly, have developed a powdered form of the phage which remains active. This would enable researchers to add the powdered phage to pig feed and see if it works in practice.
If trials in pigs work, other phage treatments could be developed for a range of animal diseases, and would speed the development of phage treatments for people.
Source: Therapy could stop superbugs on farms by Pallab Ghosh, Science Correspondent, BBC News 8 June 2017
Showing posts with label Bacteriophages. Show all posts
Showing posts with label Bacteriophages. Show all posts
Monday, 11 September 2017
Wednesday, 23 November 2016
Bacteriophages
Growing
numbers of bacteria are becoming resistant to our most powerful drugs,
evolving into new strains – often called ‘superbugs’ – that we can no
longer kill. Already drug resistance kills over 700,000 people globally
every year and could cause an extra
10 million deaths a year by 2050. A completely different approach
to killing bacteria is to use viruses.
Naturally occurring viruses called bacteriophages (from the Greek meaning ‘bacteria-eaters’) are harmless to people but lethal to bacteria. When a phage encounters its prey, it latches onto the outside and injects its own DNA inside the cell. This reproduces inside the bacterium and then the ‘daughter phages’ burst through the cell walls, before latching onto more bacteria and repeating the cycle until all the bacteria have been killed – and the infection has been dealt with.
First discovered by two different scientists – the Briton Frederick Twort in 1915 and the French-Canadian Felix d’Herelle in 1917, but it was d’Herelle who pioneered phage therapy. Abandoned in the west when antibiotics were discovered and came into common use in the 1940s. In Stalin’s Soviet Republic however, access to antibiotics was limited, so phage therapy continued and a phage therapy centre founded in Tbilisi, Georgia, became a leading centre for phage research.
Unlike antibiotics, which target a broad range of bacteria, each phage kills only one type or strain, so scientists begin by taking bacterial samples from patients and finding a phage from the lab that can kill that particular bacteria. It is much harder for bacteria to develop resistance to phages due to their diversity, their ability to evolve and their sheer abundance. Bacteriophages are actually the most abundant life form on earth – there are far more phages than there are stars in the visible universe. So if bacteria evolve to resist a particular phage, the scientists simply turn to their extensive phage library, or to nature, to find another. They also create what are known as ‘phage cocktails’ – mixtures of different phages that attack bacteria from different angles and make it much more difficult for them to develop resistance.
Currently phage therapy is not approved or regulated in the west and this is the next big challenge. The good news is that the first large scale, western standard clinical trials have now begun, so hopefully in future we see this incredible 100 year old therapy returning to Europe to help us beat the superbugs.
Related links
Could viruses called bacteriophages be the answer to the antibiotic crisis? BBC 2 Trust me, I'm a Doctor, Series 5, Episode 1 (1 Sep. 2016).
Naturally occurring viruses called bacteriophages (from the Greek meaning ‘bacteria-eaters’) are harmless to people but lethal to bacteria. When a phage encounters its prey, it latches onto the outside and injects its own DNA inside the cell. This reproduces inside the bacterium and then the ‘daughter phages’ burst through the cell walls, before latching onto more bacteria and repeating the cycle until all the bacteria have been killed – and the infection has been dealt with.
First discovered by two different scientists – the Briton Frederick Twort in 1915 and the French-Canadian Felix d’Herelle in 1917, but it was d’Herelle who pioneered phage therapy. Abandoned in the west when antibiotics were discovered and came into common use in the 1940s. In Stalin’s Soviet Republic however, access to antibiotics was limited, so phage therapy continued and a phage therapy centre founded in Tbilisi, Georgia, became a leading centre for phage research.
Unlike antibiotics, which target a broad range of bacteria, each phage kills only one type or strain, so scientists begin by taking bacterial samples from patients and finding a phage from the lab that can kill that particular bacteria. It is much harder for bacteria to develop resistance to phages due to their diversity, their ability to evolve and their sheer abundance. Bacteriophages are actually the most abundant life form on earth – there are far more phages than there are stars in the visible universe. So if bacteria evolve to resist a particular phage, the scientists simply turn to their extensive phage library, or to nature, to find another. They also create what are known as ‘phage cocktails’ – mixtures of different phages that attack bacteria from different angles and make it much more difficult for them to develop resistance.
Currently phage therapy is not approved or regulated in the west and this is the next big challenge. The good news is that the first large scale, western standard clinical trials have now begun, so hopefully in future we see this incredible 100 year old therapy returning to Europe to help us beat the superbugs.
Related links
Could viruses called bacteriophages be the answer to the antibiotic crisis? BBC 2 Trust me, I'm a Doctor, Series 5, Episode 1 (1 Sep. 2016).
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