Researchers are calling on GPs to be more responsible in prescribing a common topical cream containing antibiotics that could have contributed to New Zealand's soaring rate of staphylococcal skin infections.
Fusidic acid is presently recommended as a first-line treatment for skin infections such as school sores, the most common cause of which is the bacteria Staphylococcus aureus (S. aureus).
But a new study has found high levels of fusidic acid resistance in S. aureus skin infections in New Zealand, in another apparent case of antibiotic use inadvertently adding to drug resistance.
Clinical microbiologist Dr Deborah Williamson, who led the Health Research Council (HRC)-funded study, said there had been a significant increase in the number of S. aureus infections in New Zealand over the past decade, with Maori and Pacific children particularly affected.
New Zealand had a higher incidence of S. aureus infections than anywhere else in the developed world.
"The increase that we've seen in the incidence of serious skin infections in New Zealand children has happened at the same time as an increase in the dispensing of topical fusidic acid to treat skin infections."
Coupled with this increased use of topical fusidic acid had been a marked increase in fusidic acid resistance in S. aureus, both in Auckland and in a collection of S. aureus samples that were taken from around New Zealand.
"Since 1999 when we first measured this, fusidic acid resistance in New Zealand has almost doubled to approximately 30 per cent - that's one of the highest rates in the developed world."
In the face of such high levels of resistance, it was "highly questionable" whether fusidic acid should continue to be recommended as a first-line topical agent for school sores, she said.
"We'd like GPs, and patients, in fact, to try to take some more responsibility around appropriate prescribing - and that may mean for people, when they go to the doctor, that they don't walk out with an antibiotic."
Urgent regulatory interventions on the use of fusidic acid were needed, along with clinical trials to assess the effectiveness of alternative compounds, such as antiseptic agents, in treating school sores.
"Some people think that topical antibiotic creams aren't as big an issue when it comes to antibiotic resistance as antibiotics in tablet form because you apply it to the skin, but these topical antibiotics kill or inhibit bacteria in the same way as tablets," she said.
"We have extremely strong evidence now to show that New Zealand needs to take a hard line on the use of topical antibiotics."
HRC chief executive Professor Kath McPherson said the study was an example of how well-intentioned responses to a significant public health problem could have major unintended consequences.
"Antibacterial resistance threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi," McPherson said.
"The recent final ruling by the FDA in the US to ban the marketing of antibiotic hand and body wash products that contain certain specific antibacterial ingredients shows just how seriously we need to treat this very real threat to global public health."
The Ministry of Health's director of protection, regulation and assurance, Dr Stewart Jessamine, acknowledged antimicrobial resistance was a growing public health threat, which required collaborative action across government sectors and the community.
New Zealand was developing an action plan, due to be complete by May next year, which was being steered by Government-selected representatives from across the human health, animal health and agriculture sectors.
"At the community level, a focus on the importance of prevention and supporting self management is required," Jessamine said.
"Along with appropriate use of antibiotics, nurses working in primary care and in the community play a key role in promoting skin hygiene to prevent skin infections.
"A range of tools have been developed to include key messages such as the importance of cleaning and covering wounds, washing hands often, good food and nutrition, not sharing medicines and taking the full course of any prescribed medicines."