The waning of the antibiotic age

Fifty years ago it was hailed as a miracle drug which saved millions of lives. But misuse of penicillin and other antibiotics has meant that infectious diseases once thought conquered are on the rise again.

Scientists yesterday called for stricter controls over the use of antibiotics as a World Health Organisation report spoke of a "current crisis", with the lifespans of such drugs shortening all the time.

Infectious diseases, the main cause of premature death, kill 17 million people every year. The biggest killers are pneumonia (4.4 million), diarrhoeal diseases (3.1 million) and tuberculosis (3.1 million). All have strains which are now resistant to common antibiotics.

While diseases like TB and cholera are not a big problem in this country because of tight controls, Britain has experienced one of the most serious antibiotic-resistant bacteria, MRSA - methicillin resistant staphylococcus aureus - which it is estimated affects half our hospitals.

"The resistant organisms that are being produced are a whole new generation of organisms," Ralph Henderson, WHO's assistant director-general, warned. "This resistance problem is one that I think is going to be a major plague for the coming century."

Strains of pneumococci, the most common bacteria causing acute respiratory infections in children, were once uniformly susceptible to penicillin.

Now they are resistant in up to 18 per cent of cases in the United States and 40 per cent in South Africa.

Epidemic dysentery caused by shigella dystentriae in central and southern Africa now results in the death of up to 15 per cent of those infected, because of resistance to antibiotics.

In South-East Asia, 50 per cent of the strains of salmonella typhi, the bacteria which causes typhoid fever, are already resistant to standard antibiotics.

In Britain MRSA has caused severe problems. In 1995 about 130 hospitals reported cases and the previous year 60 people in West Midlands hospitals died after infection.

Dr Alun Davies, a consultant microbiologist said: "We are increasingly seeing the problem of MRSA in hospitals. These organisms were previously treated with antibiotics, but now they are of no use."

Infections are most common on intensive-care wards and acute surgical and orthopaedic wards. They range from trivial to life-threatening conditions, such as septicaemia (blood poisoning). In the US it is estimated that antibiotic-resistant bacteria are responsible for up to 60 per cent of hospital-acquired infections.

In some areas, staphylocci, which can contribute to skin infections, food poisoning and other serious disorders, have developed resistance to all antibiotics except vancomycin.

The WHO report warns that if vancomycin-resistant strains were to emerge, some of the most prevalent hospital- acquired infections could not be treated. "Disastrously, this is happening at a time when too few new drugs are being developed to replace those that have lost their effectiveness," the report says. "In the contest for supremacy, the microbes are sprinting ahead. The gap between their ability to mutate into drug-resistant strains and man's ability to counter them is widening fast."

"In this country we do have antibiotic resistance, but in comparison to the other parts of the world it is a small problem," said a spokeswoman for the Public Health Laboratory Service in north London. "But we have to look at very careful, appropriate usage of antibiotics given out by GPs and in hospitals. Veterinary usage also needs to be looked at."

Micro-organisms are now being exposed to "an environment heavily laced with antibiotics for humans", said Mr Henderson. Even more antibiotics are being fed to beef cattle. In many developing countries, antibiotics can be bought on the open market, while some are counterfeit.

Dr Martin Wood, editor-in-chief of the Journal of Antimicrobial Chemotherapy, called for tighter controls on the way antibiotics were dispensed.

"We need to be sure that doctors and everyone else are rethinking antibiotics. For too long doctors have regarded antibiotics as harmless agents, that it's safe to give them to most people. It may not do any harm to the individual but it's putting more and more pressure on the environment. There's an overload of people just using them like aspirin."

Thirty years ago the US surgeon general said the time had come to "close the book on infectious diseases".

Dr Wood warned yesterday: "Bacteria started breaching the bulwarks over the last 20 years. Now some strains are resistant to all antibiotics. It's just a question of time."

A sick metaphor, page 14