新聞新知~超級病菌出現，抗生素無效!!!!

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瀏覽:2026/03/16-17:42:20 公告:2010/08/12-14:18:47

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Alarm over 'unbeatable' enzyme that could make all bacterial diseases resistant to antibiotics

印度超級病菌登陸英國：一種難以殺死的酵素，能使致病的細菌對抗抗生素

By Jenny Hope
Last updated at 10:29 AM on 12th August 2010

Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study

英文原文：

Gene makes bacteria resistant to almost all antibiotics
Patients brought enzyme back from India and Pakistan

The NHS is on red alert to detect a 'superbug' resistant to the most powerful antibiotics which has been imported from India by health tourists.

There are fears that without vigilance a new gene that allows any bacteria to become a superbug could become widespread in NHS hospitals.

It has infected around 50 Britons so far, many of whom returned to the UK after undergoing surgery in India or Pakistan.

Vulnerable: Young and elderly patients will be particularly susceptible to the 'superbugs', which have emerged recently and are immune to almost all antibiotics (picture posed by model)

The Health Protection Agency (HPA) yesterday stepped up its warnings about the new gene called NDM-1, or New Delhi metallo-beta-lactamose after the place where it was first identified.

Dr David Livermore, director of antibiotic resistance monitoring at HPA, said resistance to one of the major groups of antibiotics, the carbapenems, is found throughout India.

'This is important because carbapenems were often the last 'good' antibiotics active against bacteria that already were more resistant to more standard drugs,' he said.

'We have now also identified bacteria with this type of resistance - NDM - in around 50 patients in the UK.

'Most not all, had previously travelled to the Indian subcontinent and many had received hospital treatment there.

'International travel gives a great potential for spread of resistant bacteria between countries.'

Dr Livermore added: 'Few antibiotics remain active against these bacteria.Their spread underscores the need for good infection control in hospitals both in the UK and overseas, and the need for new antibiotic development.'

The HPA flagged up the problem last year but renewed its warnings after a study in journal The Lancet Infectious Diseases tracked the emergence of the 'superbug' gene in different countries.

The researchers found NDM-1 is becoming more common in Bangladesh, India and Pakistan and is starting to be imported back to Britain in patients returning from these countries.

Several of the British NDM-1 positive patients had recently travelled to the Indian subcontinent for hospital treatment including cosmetic surgery.

Timothy Walsh, professor of medical microbiology and antimicrobial resistance at Cardiff University, who led the study, said it was a 'real concern'.

'Because of medical tourism and international travel in general, resistance to these types of bacteria has the potential to tavel around the world very, very quickly.'

He said there are few drugs in development that can potentially combat the threat.

The resistant gene has also been detected in Australia, Canada, the US, the Netherlands and Sweden.

The NDM-1 gene alters bacteria, making them resistant to nearly all known antibiotics.

It has been largely found in E. coli bacteria, the most common cause of urinary tract infections, and on DNA structures that can be easily copied and passed onto other types of bacteria.

The researchers said the superbug gene appeared to be already circulating widely in India, where the health system is much less likely to identify its presence or have adequate antibiotics to treat patients.

Christopher Thomas, professor of molecular genetics at the University of Birmingham who was not linked to the study, said 'We are potentially at the beginning of another wave of antibiotic resistance, though we still have the power to stop it.'

Prof Thomas said better surveillance and infection control procedures might halt the gene's spread.

Although patients in British hospitals are unlikely to encounter the superbug gene, they should remain vigilant about standard hygiene measures like properly washing their hands, he added.

The spread of the enzyme that makes any bug 'super'

Rising levels of antibiotic resistance are a threat because there are few new drugs in the pipeline.

Infection experts are alarmed about the spread of multi-drug resistance facilitated by the gene NDM-1 that can easily jump from one strain of bacteria to another.

If it ends up in a bacterium which is already resistant to many other antibiotics then it could produce infections that are almost impossible to treat.

NDM-1-producing bacteria are resistant to many existing antibiotics including carbapenems - a class of drugs often reserved for emergency use and 'last resort' treatment.

So far two types of bacteria have been host to NDM-1 - the gut bug E.coli and another that can invade the lungs called Klebsiella pneumonia.

Both can lead to urinary tract infections and blood poisoning.

E.coli is among a group of 'gram-negative' bugs, and the proportion of antibiotic-resistant cases of E.coli infection has trebled since the turn of the century.

There are about 20,000 E.coli bloodstream infections each year in England, Wales and Northern Ireland, of which more than one in ten is resistant to antibiotics.

There are just two antibiotics in the pipeline against this group of infections.
This compares with several new medications for gram-positive infections like MRSA.

Figures suggest it costs between
£500 million to £1 billion to bring new drugs to market.

GSK, one of a handful of giant pharmaceutial firms actively investing in antibiotic research, said: 'New antibiotics that work in different ways to existing medicines are desperately needed to tackle the rising incidence of antibiotics resistance.'

'The spread of these multi-resistant bacteria merits very close monitoring' wrote Johann Pitout of the division of microbiology at the University of Calgary, Canada, in an accompanying Lancet commentary.

He called for international surveillance of the bacteria, particularly in countries that actively promote medical tourism.

'The consequences will be serious if family doctors have to treat infections caused by these multi-resistant bacteria on a daily basis' he added.

The Department of Health spokesman said 'We are working with the Health Protection Agency. The HPA alerted the NHS in January and July lst year to be vigilant about these bacteria and take appropriate action where necessary.

'Hospitals need to ensure they continue to provide good infection control to prevent any spread, consider whether patients have recently been treated abroad and send samples to the HPA for testing.'

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