Buruli ulcer in Australia (BU)
Mycobacterium ulcerans infection
Flesh Easting Bug
(October 29, 2017) Short URL: goo.gl/h3a0b4
Outbreak ALERT: Victoria is experiencing a marked increase in new diagnoses of Buruli ulcer. Click here for weekly updates on case numbers.
How to protect your family and yourself
· Check latest endemic areas (maps below).
· Wear shoes, long sleeves and trousers when outside. (choose loose fitting, light coloured close weaved materials to maximize mosquito protection).
· Avoid insect bites (cover up, use repellents)
· Control mosquitoes and use fine mesh insect screens
· Wash and cover wounds sustained outside while working, playing or gardening
· See your doctor if concerned, ask your doctor to consider Buruli ulcer.
Pictures (confirmed BU cases, Victoria)
Leg, adult female, early diagnosis
Lower back ulcer - 12 year-old boy. The markings show the area of palpable induration (swelling) that is more extensive than the ulcer itself.
Buruli over the Achilles tendon on a 24-year-old before and after treatment with rifampicin plus clarithromycin
Buruli over the right forearm of a 30-year-old woman with delayed diagnosis.
Figure: Overlaid Google Earth image, likely place of infection, confirmed cases Victoria, 2015-2016
(WHO Meeting on Buruli ulcer, March 2017, Geneva).
What is Buruli ulcer? Buruli ulcer, Bairnsdale ulcer, Mossman ulcer and Daintree ulcer are all local names given to the same disease that is caused by Mycobacterium ulcerans--a mycobacterium related to those that cause TB and leprosy. “Buruli ulcer” or just “Buruli” is the official name preferred by WHO. Mycobacterium ulcerans produces a toxin called mycolactone that damages skin and subcutaneous fat tissue.
Which areas in Australia and New Zealand are endemic? Buruli is a geographically restricted infection, which means it only occurs following contact with specific “endemic” areas. In Australia these include coastal Victoria, north Queensland north of Mossman, the Capricorn Coast of Queensland near Yeppoon and the tropical north coast near Darwin (see map). So far no cases have been linked to Tasmania, South Australia, southern Western Australia or the ACT. There have been a handful of cases in southern New South Wales near the border with Victoria. Buruli has not been reported in New Zealand.
How do you get infected? Travel to an endemic area for as little as one hour is enough to acquire the infection. The median incubation period [time until you notice something is wrong] is approximately 5 months with a range of 3 weeks to almost a year. In Victoria there is emerging evidence that biting insects may transmit the infection and that they in turn may pick it up from infected possums or the local environment.
How common? In the years 2013-2016 combined there were at least 452 confirmed cases of Buruli in Australia, giving an approximate annual national incidence of 0.5 per 100,000 population. However, because Buruli occurs in small endemic regions the incidence in local populations can be many times higher than the national rate. Overseas there have been thousands of cases of Buruli, predominantly in rural areas in west and central Africa.
Map: Confirmed cases Australia since 1939
Graph: Confirmed cases in Victoria by year 1937-2016 [Acknowledgement: A/Prof John Hayman, cases prior to 1993].
When to suspect Buruli ulcer? Buruli usually starts as a small spot (lesion) on or under the skin that enlarges over days to weeks. Lesions typically occur on exposed areas but especially around the ankles, backs of calves or elbows. However, they can be anywhere. Buruli is often painless, and fever or other symptoms are usually absent. Eventually the spot breaks down and a slowly enlarging undermined ulcer appears but appearances can be variable and Buruli is difficult to diagnose if your doctor is not familiar with it. Diagnosis is easy once Buruli is considered in the differential diagnosis as a rapid accurate test is available (PCR).
Some patients present with a raised reddish plaque rather than an ulcer, cellulitis that does not respond to standard antibiotics or develop swelling of the whole limb or whole abdominal wall without an identifiable nodule, plaque or ulcer. Buruli progresses over days to weeks (not hours).
Do you think you have a Buruli ulcer? There is information to guide your doctor below. Buruli is always curable but treatment is simpler if diagnosis is made early. “Buruli” may be a better term than Buruli ulcer, as not all cases start as ulcers and this can confuse patients and their doctors.
How is Buruli ulcer treated? A 2-month course of antibiotics (e.g. rifampicin plus clarithromycin used together) reliably kills Mycobacterium ulcerans. Confusingly, lesions may paradoxically worsen during antibiotic treatment but this does not indicate treatment failure. Small lesions can be cured with surgical excision or heal well with antibiotics alone, but larger ones may require conservative surgical debridement and skin grafting to achieve the best result. Treatment guidelines for Australian clinicians are available here.
About this website
short URL: http://goo.gl/h3a0b4
This is a privately funded website provided as a community service. The information is intended as a guide only and should not replace medical advice from your doctor. Latest update November 2017. If you have questions/concerns about the contents or accuracy of this website please contact me by email: Paul.JohnsonATaustin.org.au
Paul Johnson (Austin Health Link)
Professor Paul Johnson
Austin Health & University of Melbourne
Director, WHO Collaborating Centre for Mycobacterium ulcerans (located at VIDRL, Doherty Institute for Infection and Immunity)
Notes on diagnosis for clinicians
RAPID DIAGNOSIS FROM A SWAB...PCR can be performed straight from the swab; make sure you can see biological material on the swab (see picture). Moisten and rub with saline if necessary. Specify “Mycobacterium ulcerans” or “Bairnsdale/Buruli ulcer” and “PCR” clearly in clinical notes on the request slip.
(Note: BU cannot by confirmed with routine “M,C,S” )
Microscopy: Acid-fast bacilli (Mycobacterium ulcerans) in a smear taken directly from a swab of an ulcer. The bacteria can be seen as red clumps on a blue background. PCR confirmed this is M. ulcerans
PLAQUE, SWELLING or CELLULITIS BUT NO ULCER, fresh tissue from an incisional biopsy, punch biopsy, fine needle aspirate or excisional biopsy will be needed. Remember to ask for Mycobacterium ulcerans PCR microscopy and culture. Histology is also very helpful.
Ankle - 23 year-old woman, plaque lesion (no ulcer apparent; diagnosed by histology and PCR on a incisional biopsy)
Links to guidelines, articles and useful sites
Department of Health (Victorian State Government)
Mornington Peninsula Shire
Buruli ulcer in Victoria, Australia
Buruli ulcer in Far North Queensland
Buruli ulcer in coastal central Queensland
World Health Organization
Public Library of Science (Journal)
Medical Journal of Australia
Proceedings of the National Academy of Science (Journal)
Genome Research (Journal)
HTML Snippet for Google Analysis