Antibiotic resistance international problem
October 11, 1999
Antibiotic resistance international problem
ANTIBIOTIC resistant "superbugs" reported in three different hospitals are nothing new but clearly illustrate the problems such infections pose when they strike people with lowered immunity, the Ministry of Health says.
"Every hospital in New Zealand probably records some instances of antibiotic resistant bacteria," Ministry spokesman Dr Bob Boyd says. "The recent reports are unusual only in that media in three different locations have within days of each other focussed on what is a longstanding and well-known problem not only in New Zealand but internationally."
Dr Bob Boyd, acting Director of Public Health, said health authorities around the world had been aware of the trend for at least 10 years, and were working in a variety of ways to combat or contain the problem.
Antibiotic resistant bacteria were a fact of life throughout the Western world. "What's particularly concerning is when they migrate into hospitals, where patients are almost by definition more susceptible to infection," he said.
Concern about the Christchurch cases had prompted the Ministry of Health to contract ESR to investigate the source of the infection. All hospital laboratories are already required to report to the Ministry, via ESR, all cases of antibiotic resistant bacteria, identifying both the strain responsible and the number of infections.
Dr Boyd said some strains were now well-established. "Whatever we come up with is not going to have any effect on MRSA and the two types of acinetobacter (the bacteria identified in Wellington and Christchurch hospitals respectively.) Our surveillance gives us good information on what we have and where. What we have to do now is focus on preventing the emergence of any more antibiotic resistant bacteria."
Preventing over-use in the community was clearly critical in achieving that. The Ministry of Health, Independent Practitoner Associations, Pharmac, the Medical Association and other groups have for some time focussed on raising awareness amongst GPs and other prescribers to limit antibiotic use.
"Here in New Zealand doctors' awareness of the risk of over-prescribing antibiotics has been raised considerably over the last five years. As well as ensuring that they are prescribing only for bacterial infections which will respond to antibiotics they are also very alert to the optimum dose, and to the need to stress to patients that they should complete any prescribed course."
"The evidence suggests that it's having an effect - prescribing rates are dropping."
Dr Boyd said there was no doubt that in the past over-prescribing - for example where an infection is viral rather than bacterial - for too long a course or the wrong sort of antibiotic, had been a factor.
"But we believe most doctors have responded well to education about the risks and modified their prescribing appropriately," Dr Boyd said.
Hospitals were also well-aware of the risks. Ways of managing antibiotic-resistant bacterial infections were currently under review in a new draft standard for infection control and isolation procedures which would update existing protocols for surveillance, testing and management of any such infections to minimise the risks to other patients.
All doctors were also being urged to keep the strongest antibiotics in reserve, as a last line of defence against any resistant infections.
Dr Boyd said experts had also turned their attention to the use of antibiotics in agriculture, both in veterinary medicine and in animal feeds.
"It's not yet proven but there is a belief that animals fed antibiotics could provide a breeding colony for resistant bacteria, which could then infect humans.
"One theory is that when a member of a farming family goes to hospital, he nor she may pass on the resistant bacteria to other patients with weak immune systems. Or they might be transmitted through the food chain."
Working parties in both the health and agriculture sectors had been discussing the issues for some time, Dr Boyd said.
The Ministry of Health monitors notifiable diseases and antimicrobial resistance in the health sector. It contracts ESR to provide antimicrobial surveillance and advice to laboratories and practitioners.
Surveillance provides data on the extent of the problem and against which control procedures and policy changes can be measured. Appropriate surveillance provides the ability to advise health professionals on the appropriate antibiotics to control disease. Information in these areas is published regularly in the Public Health Report.
The Ministry, with assistance from ESR, has produced draft infection control guidelines for healthcare institutions and has facilitated meetings of the Hospital Acquired Infection working group and the Infectious Diseases Advisory Committee.
Each public hospital laboratory and some community laboratories monitor antibiotic resistance in their local area. Each Hospital and Health Service has its own infection control committee. These provide feedback to clinicians and advice on prescribing for individual patient care and may help develop antibiotic prescribing policies for the hospital - for example limiting prescribing oral vancomycin to situations where it is specifically needed to prevent the development of vancomycin resistant enterococci. Two expert committees provide specialist advice to the Ministry of Health. The Infectious Diseases Advisory Committee provides technical and scientific advice to the Director-General of Health concerning infectious diseases. This involves: providing advice on technical and scientific issues related to infectious diseases including prevention, control, surveillance and outbreak investigation providing advice on infectious diseases goals and targets and options to achieve these monitoring national and international developments in relation to infectious diseases monitoring and reviewing relevant infectious diseases standards and guidelines
The Hospital Acquired Infections working party was established last year . It provides advice to the Director-General of Health, including the advice of infectious diseases specialists and clinicians working in hospitals.
The public play an important role in preventing the emergence and spread of antimicrobial resistant organisms. Anyone prescribed antibiotics should complete the full course of the medicine. Individuals who stop taking the antibiotics once the symptoms have lessened but before they have finished their complete course of medication often have not killed all the bacteria. Surviving bacteria can cause a reinfection, often with increased resistance to the antibiotic in question.
Individuals should become more aware of the common causes of illness and accept that every visit to the doctor should not result in a prescription. Many common diseases are caused by viruses against which antibiotics, and most medicines, are ineffective. Prescribing and taking antibiotics in these instances increase the exposure of bacteria to antibiotics and can help unnecessarily increase resistance to antibiotics.
New Zealand has a low rate of antimicrobial resistance compared with many other countries.