As the coronavirus pandemic is hitting the whole world hard, vigilance regarding viruses and bacteria appears to be growing stronger. And in Australia, it is a flesh-eating disease that is worrying scientists because each year, the number of cases increases significantly. It is the Buruli ulcer, a bacterial disease that was discovered in 1897 in Uganda.
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It has spread to several countries including Australia where the first case was recorded in 1948 near Melbourne in the State of Victoria. It is still not known how it got there and that mystery does not seem like it'll be solved any time soon. Why? Because it has been classified by the WHO as a neglected tropical disease, that is to say that the research time it was allotted is near zero, because it mainly affects disadvantaged populations.
The WHO reported nearly 1,961 cases in 2016 overall. A figure that jumped to 2,713 in 2018. This increase is also seen in Australia where cases seem to be concentrated in the Mornington Peninsula County near Melbourne. There were 65 cases in 2014, up to 299 in 2019. This particular trend worries Daniel O'Brien, infectious disease specialist and Buruli ulcer expert, who works tirelessly to discover all the specifics of this condition.
Symptoms and treatment
This disease destroys the skinand can even attack soft tissue if left untreated. Daniel O'Brien explained to the BBC:
It can really eat away at an entire limb.
To overcome this, patients are given doses of strong antibiotics that must be taken for several weeks or even months. These are rifampicin, used for tuberculosis or leprosy, and moxifloxacin, which is usually a treatment for the plague. Depending on the severity of the ulcer, doses of steroids may be given and surgery may be necessary. One of Daniel O'Brien's patients needed nearly 20 operations.
Note that while the ulcer in itself is disabling and can leave after-effects, it is also the case of its treatment. It is very uncomfortable for patients and causes side effects such as digestive problems or nausea.
How is it transmitted?
While this disease can be very dangerous for humans, we do not yet know exactly how it is transmitted. So Daniel O'Brien collaborates with other scientists to try to understand. And their hypothesis would be that of zoonosis, that is to say that it would be transmitted from animals to humans. This could be explained in particular by the growing proximity between animals and us. And the number one suspect would be the possum, a protected species in the country. Kim Blasdell, researcher at the Australian national science agency, explains:
There is a lot of development in areas where there have been a lot of human cases. […] When people clear the land to build a new house or remove natural vegetation, it means that the animals that live on this land, including opossums, are pushed back into the remaining vegetation area. This has the effect of concentrating the number of possums.
In addition, possums would acclimatize very well to urban life and they do not hesitate to live in garden trees, for example. These little animals are already monitored, but mosquitoes, whose populations have increased significantly in recent years are also drawing attention.
Thus, teams of researchers are multiplying their surveys and samples to study the environment of people who had been infected. They therefore examined the possum presence rate and analysed their faeces, which could be involved; they identified the concentrations of mosquitoes in order to gather as much information as possible. For Daniel O'Brien,
It is a disease that has a complex interaction with the environment, with animals and with people.
The influence of coronavirus
While ongoing research into Buruli ulcer was on track already, coronavirus has had a strong impact. In fact, they stopped research and the funds necessary to undergo that research have become harder to find. According to Daniel O'Brien, there is too little knowledge about the disease, especially the conditions of its transmission. If you don't get answers, controlling its expansion while it's still small-scale will soon be very difficult, possibly reaching the epidemic scale.
