Tag Archives: infectious diseases

Antibiotics resistance

The danger posed by growing resistance to antibiotics should be ranked along with terrorism on a list of threats to the nation, the government’s chief medical officer for England has said.

Professor Dame Sally Davies described it as a “ticking time bomb”.

She warned that routine operations could become deadly in just 20 years if we lose the ability to fight infection.

Dame Sally urged the government to raise the issue during next month’s G8 Summit in London.

Dame Sally said: “If we don’t take action, then we may all be back in an almost 19th Century environment where infections kill us as a result of routine operations. We won’t be able to do a lot of our cancer treatments or organ transplants.”

She said pharmaceutical companies needed to be encouraged to develop new drugs, because the manufacture of antibiotics was not viewed as profitable.

“We haven’t had a new class of antibiotics since the late 80s and there are very few antibiotics in the pipeline of the big pharmaceutical companies that develop and make drugs,” she said.

“We haven’t as a society globally incentivised making antibiotics. It’s quite simple – if they make something to treat high blood pressure or diabetes and it works, we will use it on our patients every day.

“Whereas antibiotics will only be used for a week or two when they’re needed, and then they have a limited life span because of resistance developing anyway.”

Dame Sally said action was needed to overcome this “market failure” and pointed to the Innovative Medicines Initiative – an EU funded body whose aim is to promote the development of new medicines.

Dr Ibrahim Hassan, a consultant microbiologist at Wythenshawe Hospital in Manchester, said there are more cases of patients with bacterial infections resistant to antibiotics – meaning there are fewer treatment options.

“All you can hope of is a bit of holy water because you don’t have too much option in terms of treatment.

“We’re beginning to see that in some hospitals, patients coming in with this infection with no antibiotic that can be used to treat them.”

Dame Sally’s warning coincides with the publication of the second volume of her annual report which details the burden posed by infectious diseases.

Death rates for infectious diseases have declined in developed countries in recent decades due to improvements in hygiene and sanitation, widespread immunisation and effective drug treatments.

But the report says they still account for 7% of all deaths in England and account for one in five days off work.

It says in decades to come we risk “losing the war” against microbes – and standard surgical procedures such as hip replacements could become riskier, as would treatments that suppress the immune system such as chemotherapy or organ transplant.

Antibiotics

Antibiotics

Dame Sally said it was a global issue for governments, the medical profession, the pharmaceutical industry and individuals.

She also said the over-use of antibiotics was an issue in animal husbandry, agriculture and fish farming.

She urged politicians to treat the threat as seriously as the superbug meticillin (also called methicillin)-resistant Staphylococcus aureus or MRSA.


Cases have fallen by 80% since 2003 through improved hygiene measures in hospitals.

Health officials say other infections have now overtaken MRSA as major sources of healthcare-acquired infections.

In particular, cases of E.coli and Klebsiella bacteria have increased by two-thirds in recent years and are now the most frequent cause of hospital acquired infection.

Both types of bacteria – known as Gram negative – are commonly found in the gut but can cause blood infections.

In England, Wales and Northern Ireland 99,000 cases of blood stream infections were reported in 2011-12. E.coli alone accounted for 36% of cases compared with just 1.6% due to MRSA.

The report estimates that up to 5,000 patients a a year die from Gram-negative blood poisoning each year, half with an antibiotic-resistant organism.

Dame Sally said no new classes of antibiotics had been introduced since 1987 whereas new pathogens were emerging every year, and existing bugs were developing resistance to current treatments.

A five-year UK Antimicrobial Resistance Strategy will be published shortly which will advocate the responsible use of antibiotics and strengthened surveillance.

The Chief Medical Officer said antimicrobial resistance would be put on the government’s national risk register of civil emergencies – which provides guidance on potential threats such as terrorist attacks, pandemic flu and major flooding.

Dame Sally said she was shocked by the “woeful education” in antimicrobial resistance given to many medical students and doctors; she wanted to ensure fewer antibiotics were prescribed, so that they are used only when needed.

Dame Sally is not the first chief medical officer to warn of the dangers of antibiotic overuse.

In 2008 her predecessor, Liam Donaldson, urged doctors not to use antibiotics to treat colds and coughs as these are caused by viruses and do not respond to antibiotics.

In 1999, Sir Kenneth Calman made a similar plea, saying the public had a responsibility not to demand antibiotics.

MRSA strain USA300 in the UK

A flesh-eating form of pneumonia that is easily passed between healthy people on public transport is spreading across the UK, experts have warned.

The deadly strain of MRSA called USA300 passes easily through skin-to-skin contact. It can also survive on surfaces and so has the potential to be picked up on crowded buses and tubes.

It was first seen in the U.S but cases are now being reported in the community and not just hospitals in Britain.

Dr Ruth Massey, from the Department of Biology and Biochemistry at the University of Bath, said extra vigilance was required around this and similar MRSA bugs known as PVL-positive community acquired strains.

USA300 is resistant to treatment by several front-line antibiotics and can cause large boils on the skin. In severe cases, USA300 can lead to fatal blood poisoning or a form of pneumonia that can eat away at lung tissue.

Dr Massey said there were 1,000 cases of PVL-positive community acquired MRSA in England in the last year, of which 200 were USA300 strains.

‘These community-acquired strains seem to be good at affecting healthy people – they seem to be much better than the hospital ones at causing disease.

‘They don’t rely on healthcare workers moving them around, which the hospital ones seem to.’

Dr Massey said USA300 is ‘a really big issue in the U.S. and it’s starting to emerge here.

‘But hopefully because we are aware of it and are working to understand it, it won’t become as big of a problem (in the UK).’

In a new research paper published in the Journal of Infectious Diseases, Dr Massey and colleagues analyse the way community-acquired MRSAs are able to adapt and fine tune themselves to spread outside of hospitals.

MRSA bacteria in hospitals has not been able to migrate into the community in the same way.

Dr Massey said: ‘Our research found that the composition of the cell wall of the bacteria is critical to the community-acquired bacteria being more toxic.

‘The ability of the MRSA bacteria to secrete toxins is one of the main ways it causes disease.

‘Using a sensing system, it carefully controls when it switches on its ability to do this, so as not to cause disease until it is firmly established within the human.

MRSA

MRSA

‘Many antibiotics target the cell walls of harmful bacteria, and to resist this, the bacteria have to make changes to their cell wall.’

Community-acquired MRSA strains have cell walls that are different to those seen in hospitals, allowing them to sense their environment and switch toxin expression on at the right time.

Justine Rudkin, a PhD student working on the project, said: ‘The community-acquired bacteria has evolved further, and is able to maintain a higher level of toxicity while also resisting treatment from antibiotics, making it a much larger problem.’


She added: ‘While we are constantly learning more about MRSA, there is a serious threat posed by this newer strain of bacteria capable of causing disease and even death in perfectly healthy people.

‘We need to respond seriously to this threat as it reaches Britain from the United States.’

Chris Thomas, professor of molecular genetics at the University of Birmingham, said: ‘The key message is that strains of MRSA that are spreading in the community are better able to infect the young and healthy, precisely because they are not actually trying so hard to be resistant as the bugs that have been encountered in hospitals for many years.’

He said there was now a ‘need to worry about community super bugs that are fine tuned to spreading outside of hospitals and we all need to be extra vigilant about hygiene and unnecessary use of antibiotics.’

A spokeswoman for the Health Protection Agency (HPA) said: ‘The paper highlights some important observations which helps us understand at the molecular level why hospital strains of MRSA are less virulent than the so-called community MRSA strains.

‘We have known about community MRSA for over a decade and, whilst they are responsible for a high burden of disease in North America, this is not the case in the rest of the world.

‘In England we have seen sporadic cases of this type of MRSA most often causing boils and abscesses, but it has not emerged as a major public health issue in this country.

‘The HPA are carrying out active surveillance of this type of bacteria and advise healthcare professionals on correct infection control procedures to reduce the likelihood of spread.’