Aedes notoscriptus mosquito is out in Australia…

i’Buruli ulcer (UB) has been reported in 33 countries in Africa, the Americas, Asia and the Western Pacific. With the exception of Australia and Japan, most cases occur in tropical and subtropical regions. BU is caused by a bacterium present in the environment, Mycobacterium ulcerans. Its mode of transmission is poorly understood.

In Australia in the 1990s, the epidemiology of BU changed and the number of cases began to increase around major metropolitan cities. Melbourne And Geelong In L’State of Victoria, in southeastern Australia. Since 2017, an average of 300 confirmed BU cases have been reported annually.

In Australia, opossums are the main reservoir M. ulcersBecause not only do they create purulent sores, they also exfoliate M. ulcers In their feces.

A study was recently published on the web bioRxiv He assumes that it is a mosquito Aedes notoscriptus Participates in the exchange M. ulcers in humans from an opossum reservoir in southeastern Australia. The arguments in favor of this hypothesis are as follows:

• M. ulcers 25% of the 72,000 mosquitoes sampled were searched Mornington Peninsula, part of south-east Melbourne has the disease. The search was almost positive A. notoscriptus (Positive rate 5.8/1,000), daytime biting type of mosquito.
• Analysis of captured mosquitoes shows that a small number of these insects have recently fed on both opossums and humans.
• Genetic analyzes have also revealed bacteria M. ulcers Mosquitoes, opossums and humans are alike.
• There is geographic overlap between areas with infected mosquitoes, areas with bacterially contaminated opossum waste, and areas with human detection of BU.

On the other hand, the correct transfer method M. ulcers From animals to humans A. notoscriptus is not identified. Two assumptions prevail:

• A. notoscriptus Opossums can feed on lesions and then transmit the bacteria to humans, but other types of mosquitoes analyzed by the researchers feed on opossums and do not carry the bacteria; Bacteria.
• Abundant with opossum excrement M. ulcers They can contaminate the water they lay A. notoscriptus leading to infection by developing mosquitoes.

Source: bioRxiv