Staphylococcal bacteria evolve resistance to antibiotics, causing outbreaks which are difficult to treat. Image / 123RF
Sixty years ago an epidemic of penicillin-resistant bacteria in hospitals killed newborn babies and left hundreds of mothers infected.
Now an infection expert is warning the lessons of that epidemic have been forgotten, with one of the main causes - overuse of antibiotics - still rife in New Zealand.
Staphylococcus aureus is a bacteria commonly found on human skin but easily develops resistance to antibiotics, with potentially fatal consequences.
Known as the "Hospital Bug" or H-bug, a penicillin-resistant strain of S. aureus first rose to prominence with the deaths of eight babies born at the private Calvary Hospital in Christchurch in 1955.
The babies' deaths "shocked the nation and undermined public trust in the maternity services", infection expert Dr Deborah Jowitt writes in today'sedition of the New Zealand Medical Journal.
"Babies developed skin lesions and serious respiratory infections while breastfeeding women developed mastitis, breast abscesses and infections of the genital tract."
In 1956, New Zealand's director-general of health Dr John Cairney had cited an "orgy of indiscriminate use" of antibiotics as being to blame for the rise of S. aureus.
But with doctors reliant on antibiotics to treat infection, health authorities did not act to change prescribing habits, instead focusing on other measures such as changing how babies were cared for, Jowitt writes.
A radical overhaul of maternity services, better infection controls and more potent antibiotics eventually ended the epidemic, which had come in the middle of the post-war baby boom.
With more than 55,000 babies born in 1955, hospitals were overwhelmed and shortstaffed and babies were crammed into crowded nurseries.
"Women were nursed under strictly imposed routines, including prolonged bed rest and 'aseptic' perineal swabbing designed to keep 'the vulva and perineum in a state of surgical cleanliness'," Jowitt writes.
"Their babies remained in communal nurseries apart from their four-hourly feeds; often arriving in closely packed 'baby wagons' at their mother's bedsides."
While midwives and nurses were portrayed as the "arbiters of aseptic practice", in fact medical staff were spreading infection as they shuttled babies back and forth.
A survey of National Women's Hospital in 1955 found 50 per cent of doctors and 27 per cent of nurses were carrying the H-bug, often in their nasal cavities. Very few newborns carried the bug but by 4 days old some 40 per cent of babies were carriers.
When health authorities realised the problem, they overhauled maternity practices to encourage the practice of babies sleeping in the same room as their mothers,
Disease surveillance was improved, and staff were swabbed and those carrying the bacteria treated, while those with infected lesions were stood down.
Better infection controls, such as handwashing, and more potent antibiotics eventually helped end the epidemic, eight years after it started.
But while rooming-in and other infection controls like handwashing became embedded in the health care system, there was no clampdown on antibiotic prescribing.
"The immediate crisis was over, restricted antibiotics returned to general use and the H-bug epidemic was largely forgotten except by those who had experienced the severity of its effects," Jowitt writes.
"The rapidly changing landscape of antimicrobial resistance", including new superbugs emerging, "reinforces the need for real change in prescribing patterns in New Zealand, which are excessive when compared with many western countries", Jowitt writes.
She is calling on the medical profession to remember the lessons of the H-bug epidemic.
"Infection surveillance, timely reporting and multidisciplinary involvement in the implementation of effective infection prevention measures still underpin efforts to prevent the spread of resistant microbes, protect patients from infection and reduce the need for antibiotic treatment."