There are likely to be more deaths from antibiotic-resistant superbugs but a ''doomsday'' scenario is unlikely, University of Otago Webster Centre for Infectious Diseases director Prof Kurt Krause says.
Antibiotic-resistant superbugs were becoming more common overseas, Prof Krause said.
''It is a significant concern that they will continue to spread. The South Island has [traditionally] been spared large numbers of resistant organisms, compared to other countries and even the North Island.''
Methicillin-resistant Staphylococcus aureus (MRSA) was a type of superbug, but it was not resistant to all types of antibiotics.
Wellington teacher Brian Pool (68) is thought to be the first New Zealander to have contracted a superbug resilient to every antibiotic. He died in July from complications caused by a stroke, but his immune system was weakened by the superbug, Fairfax reported.
He became ill in Vietnam and was flown to Wellington Hospital, where tests found he was carrying the strain of bacterium known as KPC Oxa 48.
''It's likely that we'll see more and more [antibiotic-resistant superbugs] just because they're spreading everywhere else in the world,'' Prof Krause said.
He stressed the most resistant superbugs were not necessarily more likely to infect people.
''The problem is, if they do cause disease, they're more difficult to treat.''
Hospital infection-control measures, which were already at a high standard in New Zealand, would become more important.
Antibiotic practices had improved and these efforts should be stepped up, although it was probably ''a little bit too late'' to stem the considerable problem that had developed.
''We have not done a very good job at husbanding our antibiotics. We use antibiotics inappropriately.''
Once prescribed, antibiotic courses should be taken in full, and they should never be taken for viral illnesses.
He was critical of the practice of adding them to animal feed, which might be effective for increasing primary production yields ''but at what cost?''
Governments needed to help pharmaceutical companies fund antibiotic development. Initiatives were under way overseas but they could take years to bring new antibiotics to the market.
This year, Britain's chief medical officer, Prof Dame Sally Davies, warned that in another two decades, surgery could almost be as risky as in the 19th century, because of the antibiotic-resistance problem.
Prof Krause disagreed with that prognosis but believed it was being overstated because more measured warnings over the past 20 years or so had not been heeded.
There had been great advances in hospital care since the 19th century other than antibiotics.
''I wouldn't say we were looking at doomsday yet, but we really do need action right now to be prepared to address these bugs.''
An information sheet on antibiotic resistance and food on the Ministry of Primary Industries' website said antibiotics were used for illness, and as a preventive measure against disease.
Antibiotics were ''essential for the health and welfare of animals'' but in New Zealand, could be used to promote animal growth only if they were not implicated in antibiotic resistance.