* Report finds antibiotic resistance rife across world
* WHO expert says "world is headed for post-antibiotic era"
* Bacteria evolve to evade even the most powerful drugs
* In some countries half of patients can't be treated
By Kate Kelland, Health and Science Correspondent
LONDON, April 30 (Reuters) - The spread of deadly superbugs that evade even the most powerful antibiotics is no longer a prediction but is happening right now across the world, United Nations officials said on Wednesday.
Antibiotic resistance has the potential to affect anyone, of any age, in any country, the U.N.'s World Health Organisation (WHO) said in a report. It is now a major threat to public health, of which "the implications will be devastating".
"The world is headed for a post-antibiotic era, in which common infections and minor injuries which have been treatable for decades can once again kill," said Keiji Fukuda, the WHO's assistant director-general for health security.
In its first global report on antibiotic resistance, with data from 114 countries, the WHO said superbugs able to evade event the hardest-hitting antibiotics - a class of drugs called carbapenems - has now been found in all regions of the world.
Drug resistance is driven by the misuse and overuse of antibiotics, which encourages bacteria to develop new ways of overcoming them.
Only a handful of new antibiotics have been developed and brought to market in the past few decades, and it is a race against time to find more as bacterial infections increasingly evolve into "superbugs" resistant to even the most powerful last-resort medicines reserved for extreme cases.
One of the best known superbugs, MRSA, is alone estimated to kill around 19,000 people every year in the United States - far more than HIV and AIDS - and a similar number in Europe.
THE DRUGS DON'T WORK
The WHO said in some countries, because of resistance, carbapenems now do not work in more than half of people with common hospital-acquired infections caused by a bacteria called K. pneumoniae, such as pneumonia, blood infections, and infections in newborn babies and intensive-care patients.
Resistance to one of the most widely used antibiotics for treating urinary tract infections caused by E. coli -medicines called fluoroquinolones - is also very widespread, it said.
In the 1980s, when these drugs were first introduced, resistance was virtually zero, according to the WHO report. But now there are countries in many parts of the world where the drugs are ineffective in more than half of patients.
"Unless we take significant actions to improve efforts to prevent infections and also change how we produce, prescribe and use antibiotics, the world will lose more and more of these global public health goods and the implications will be devastating, "Fukuda said in a statement.
Laura Piddock, director of Antibiotic Action campaign group and a professor of microbiology at Britain's Birmingham University, said the world needed to respond as it did to the AIDS crisis of the 1980s.
"Defeating drug resistance will require political will, commitment from all stakeholders and considerable investment in research, surveillance and stewardship programmes," she said.
Jennifer Cohn of the international medical charity Médecins Sans Frontières agreed with the WHO's assessment and confirmed the problem had spread to many corners of the world.
"We see horrendous rates of antibiotic resistance wherever we look in our field operations, including children admitted to nutritional centres in Niger, and people in our surgical and trauma units in Syria," she said.
(Editing by Angus MacSwan)