Prevalence, emergence, and factors associated with a viral papillomatosis and carcinomatosis syndrome in wild, reintroduced, and captive western barred bandicoots (Perameles bougainville).

Once widespread across western and southern Australia, wild populations of the western barred bandicoot (WBB) are now only found on Bernier and Dorre Islands, Western Australia. Conservation efforts to prevent the extinction of the WBB are presently hampered by a papillomatosis and carcinomatosis syndrome identified in captive and wild bandicoots, associated with infection with the bandicoot papillomatosis carcinomatosis virus type 1 (BPCV1). This study examined the prevalence and distribution of BPCV1 and the associated syndrome in two island and four mainland (reintroduced and captive) WBB populations in Western Australia, and factors that may be associated with susceptibility to this syndrome. BPCV1 and the syndrome were found in the wild WBB population at Red Cliff on Bernier Island, and in mainland populations established from all or a proportion of founder WBBs from Red Cliff. BPCV1 and the syndrome were not found in the wild population on Dorre Island or in the mainland population founded by animals exclusively from Dorre Island. Findings suggested that BPCV1 and the syndrome were disseminated into mainland WBB populations through the introduction of affected WBBs from Red Cliff. No difference in susceptibility to the syndrome was found between Dorre Island, Bernier Island, and island-cross individuals. Severity of lesions and the number of affected animals observed in captivity was greater than that observed in wild populations. This study provided epidemiological evidence to support the pathological and molecular association between BPCV1 infection and the papillomatosis and carcinomatosis syndrome and revealed increasing age as an additional risk factor for this disease.