Australian doctors claim they have solved the 80-year mystery of how Buruli ulcer spreads from possums to humans after finding “irrefutable evidence” to implicate mosquitoes as the principal vector.

The Doherty Institute–led team in Melbourne — who collected 74,000 mosquitoes across a 350km² area in Victoria endemic for the necrotising skin disease — says its three-pronged study finally confirms the missing zoonotic link.

Australia is the only developed country where significant transmission of Buruli ulcer has been reported, with cases surging in Victoria from 12 cases in 2003 to 363 last year.

Infectious diseases physician and study co-author Professor Paul Johnson said they had long suspected the insect was a vector for transmitting the disease-causing Mycobacterium ulcerans to humans.