Millions of people in Europe, North America and Australia will die from superbug infections unless countries prioritise fighting the growing threat posed by bacteria immune to most known drugs, experts predicted Wednesday.

The Organisation for Economic Co-operation and Development (OECD) warned of "disastrous consequences" for public healthcare and spending unless basic hospital hygiene is boosted and unnecessary antibiotic use slashed.

Drug-resistant bacteria killed more than 33,000 people in Europe in 2015, according to new research published separately this week.

In a landmark report, the OECD said 2.4 million people could die from superbugs by 2050 and said the cost of treating such infections would balloon to an average of $3.5 billion (three billion euros) a year in each country included in its analysis.

Michele Cecchini, lead on public health at the OECD, told AFP that countries were already spending an average of 10 per cent of their healthcare budgets on treating antimicrobial-resistant (AMR) bugs.

"AMR costs more than the flu, more than HIV, more than tuberculosis.

And it will cost even more if countries don't put into place actions to tackle this problem," he said.

As humans consume ever more antibiotics -- either through prescriptions or agriculture and livestock products given medicines to stave off infection -- strains of bacteria are developing that resist the effects of drugs designed to kill them.

In low and middle-income countries, resistance is already high: in Indonesia Brazil and Russia up to 60 per cent of bacterial infections are already resistant to at least one antibiotic.

And the growth of AMR infections is predicted to be between four and seven times faster by 2030 than currently.

"Such high resistance rates in health care systems, which are already weakened by constrained budgets, will create the conditions for an enormous death toll that will be mainly borne by new-borns, very young children and the elderly," the report said.

"Even small cuts in the kitchen, minor surgery or diseases like pneumonia could become life-threatening."

Perhaps more worrying is the prediction made by the OECD that resistance to so-called 2nd- and 3rd-line antibiotics -- break-glass-in-case-of-emergency infection treatments -- will balloon by 70 per cent by 2030.

"These are antibiotics that as far as possible we don't want to use because we want these as back up," Cecchini said.

"Essentially, we are using more when we should use less and we are running out of our best options in case of emergency."

The group, which advises the World Health Organization on public health initiatives, said the only way to avert disaster was to implement immediate, sector-wide changes in behaviour.

The report called on healthcare professionals to ensure better universal hygiene standards in hospitals and clinics by insisting all staff wash their hands and conform to stricter safety regimes.

It also suggested resistance could be fought with better and quicker testing to determine if an infection is viral -- meaning antibiotics are useless -- or bacterial.

New swab tests can give a result in a matter of minutes, and Cecchini also put forward the idea of "delayed prescriptions" to dent antibiotic overuse by making patients wait three days before picking up their antibiotics -- roughly the time it takes for a viral infection to run its course.

In trials of the technique, two thirds of patients given delayed prescriptions for antibiotics never collected their medicine.

The OECD said such changes would cost as little as $2 (1.7 euros) per person per year and would save millions of lives and billions of dollars by mid-century.

"They would decrease burden of AMR in these countries by 75 per cent," said Cecchini.

"It would pay for itself in a few months and would produce substantial savings.