Friday, 25 January 2013

Superbugs


Antibiotic-resistant diseases pose 'apocalyptic' threat, top expert says
Chief medical officer Dame Sally Davies tells MPs issue should be added to national risk register of civil emergencies


23 January, 2013

Britain's most senior medical adviser has warned MPs that the rise in drug-resistant diseases could trigger a national emergency comparable to a catastrophic terrorist attack, pandemic flu or major coastal flooding.

Dame Sally Davies, the chief medical officer, said the threat from infections that are resistant to frontline antibiotics was so serious that the issue should be added to the government's national risk register of civil emergencies.

She described what she called an "apocalyptic scenario" where people going for simple operations in 20 years' time die of routine infections "because we have run out of antibiotics".

The register was established in 2008 to advise the public and businesses on national emergencies that Britain could face in the next five years. The highest priority risks on the latest register include a deadly flu outbreak, catastrophic terrorist attacks, and major flooding on the scale of 1953, the last occasion on which a national emergency was declared in the UK.

Speaking to MPs on the Commons science and technology committee, Davies said she would ask the Cabinet Office to add antibiotic resistance to the national risk register in the light of an annual report on infectious disease she will publish in March.

Davies declined to elaborate on the report, but said its publication would coincide with a government strategy to promote more responsible use of antibiotics among doctors and the clinical professions. "We need to get our act together in this country," she told the committee.

She told the Guardian: ""There are few public health issues of potentially greater importance for society than antibiotic resistance. It means we are at increasing risk of developing infections that cannot be treated – but resistance can be managed.

"That is why we will be publishing a new cross-government strategy and action plan to tackle this issue in early spring."

The issue of drug resistance is as old as antibiotics themselves, and arises when drugs knock out susceptible infections, leaving hardier, resilient strains behind. The survivors then multiply, and over time can become unstoppable with frontline medicines. Some of the best known are so-called hospital superbugs such as MRSA that are at the root of outbreaks among patients.

"In the past, most people haven't worried because we've always had new antibiotics to turn to," said Alan Johnson, consultant clinical scientist at the Health Protection Agency. "What has changed is that the development pipeline is running dry. We don't have new antibiotics that we can rely on in the immediate future or in the longer term."

Changes in modern medicine have exacerbated the problem by making patients more susceptible to infections. For example, cancer treatments weaken the immune system, and the use of catheters increases the chances of bugs entering the bloodstream.

"We are becoming increasingly reliant on antibiotics in a whole range of areas of medicine. If we don't have new antibiotics to deal with the problems of resistance we see, we are going to be in serious trouble," Johnson added.

The supply of new antibiotics has dried up for several reasons, but a major one is that drugs companies see greater profits in medicines that treat chronic conditions, such as heart disease, which patients must take for years or even decades. "There is a broken market model for making new antibiotics," Davies told the MPs.

Davies has met senior officials at the World Health Organisation and her counterparts in other countries to develop a strategy to tackle antibiotic resistance globally.

Drug resistance is emerging in diseases across the board. Davies said 80% of gonorrhea was now resistant to the frontline antibiotic tetracycline, and infections were rising in young and middle-aged people. Multi-drug resistant TB was also a major threat, she said.

Another worrying trend is the rise in infections that are resistant to powerful antibiotics called carbapenems, which doctors rely on to tackle the most serious infections. Resistant bugs carry a gene variant that allows them to destroy the drug. What concerns some scientists is that the gene variant can spread freely between different kinds of bacteria, said Johnson.

Bacteria resistant to carbapenems were first detected in the UK in 2003, when three cases were reported. The numbers remained low until 2007, but have since leapt to 333 in 2010, with 217 cases in the first six months of 2011, according to the latest figures from the HPA.



Leading scientists condemn decision to continue controversial research into deadly H5N1 bird-flu virus
Research has already led to the creation of a mutated form of avian flu that can spread easily between mammals – including humans



23 January, 2013


Leading scientists have condemned a decision by flu researchers to continue their controversial research into the deadly H5N1 bird-flu virus, which has already led to the creation of a mutated form of avian flu that can spread easily between mammals – including humans.

Forty of the world’s most prominent flu researchers have decided to lift their voluntary moratorium on studies into the airborne transmission of the H5N1 strain of bird-flu, which they imposed upon themselves last January following public outrage over the work.

They said that the benefits of the research in preventing and dealing with a future flu pandemic outweigh the risks of an accidental leak of the mutant virus from a laboratory or the deliberate attempt to create deadly strains of flu by terrorists or rogue governments.

However, other leading scientists vehemently denounced the decision on the grounds that it would be more dangerous to proceed with the research than to continue with the moratorium, claiming that there has been little discussion of the decision outside the flu-research community.

Professor Lord May, a former government chief scientist and past president of the Royal Society, said the moratorium should be continued because there are two possible downsides to research that deliberately aims at making the H5N1 bird-flu virus more infectious to humans.

As this research becomes more widely known and disseminated, there is the opportunity for evil people to pervert it. My other concern is the statistics of containment are not what they ought to be,” Lord May told The Independent.

The dangers of going ahead with the research outweigh the benefits of what may emerge. As I look at it, on the balance of probabilities, going ahead and lifting the moratorium is more dangerous than not going ahead,” he said.

Sir Richard Roberts, who won the Nobel Prize in medicine in 1993 and is an expert in genetic engineering, said there has not been enough public consultation about the work. “The decision to lift the moratorium, which seems to have been made a small group of self-interested scientists, makes a mockery of the concept of informed consent,” Sir Richard said.

The ending of the voluntary moratorium was announced last night in the form of a letter signed by 40 flu scientists to the journals Science and Nature, which published the original H5N1 transmissions studies by Ron Fouchier of the Erasmus Medical Centre in Rotterdam and Yoshihiro Kawaoka of the University of Wisconsin-Madison.

The scientists independently discovered that they could mutate the H5N1 strain of bird-flu so that it could be transmitted through the air between laboratory ferrets, the standard animal model used to study influenza in humans.

Although H5N1 can pass from infected poultry to people, it is not easily transmitted from one person to another – unlike ordinary flu. However, scientists fear that if airborne transmission became possible it would lead to a deadly flu pandemic killing millions of people because most of the individuals who are known to have been infected with H5N1 die from the virus.

Dr Fouchier said that it was important to re-start the transmissions studies because it will help to identify the precise genetic mutations that make the H5N1 virus capable of passing from one person to another through the air.

We really need to understand how these viruses become airborne. With the knowledge of these mutations we can do better surveillance to identify where these mutations are popping up in nature,” Dr Fouchier said.

Dr Kawaoka said: “We want the world to be better prepared than we are. We understand the risk and consider the H5N1 research safe. There can never be zero risk, but the risk can be managed and we believe the benefits of H5N1 research outweigh the risks.”

However, other virus experts disagreed. Simon Wain-Hobson, professor of virology at the Pasteur Institute in Paris, said he was taken by surprise by the suddenness of the announcement to end the moratorium.

There has been no consultation with any virologist outside the flu community on this and, as a virologist, I’m not convinced of the benefits of this research,” Professor Wain-Hobson said.

The risks are clear for all to see and the benefits are qualitative, and that’s rather weak. Civil scientists are not here to increase the risk from microbes. We are not here to make the microbial world more dangerous,” he said.

Although the flu researchers have now abandoned their one-year moratorium, the transmissions studies with live H5N1 are not likely to start soon. The US Government has yet to decide on guidelines for research that it funds, and both Dr Fouchier and Dr Kawaoka are funded by the US National Institutes of Health.

However, Dr Fouchier said that it may start the work again with research funds he receives from the EU and the work could begin within the coming weeks.



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