LAUSR

Primum non nocere—first do no harm—is a familiar idiom in medicine and valuable advice for those involved in planning and undertaking intensive conservation interventions in conservation emergencies such as Australia’s bushfires. The risk of introducing or amplifying infectious disease to a threatened species in such interventions is real, and effective mitigation of this risk demands its prioritization in emergency conservation responses. Southern and eastern Australia have experienced bushfires of unprecedented scale and intensity since September 2019 (Nolan et al. 2020), raising legitimate concern for survival of wildlife populations and species. Governmental and nongovernmental agencies are implementing or considering emergency conservation interventions to improve survival probability of species affected by bushfire. Although justified, some interventions can increase risk of introducing or amplifying infectious diseases in wildlife, which could have significant, long-term consequences for individuals and populations. Infectious disease has emerged as a significant threat to wildlife. Prominent examples include avian malaria in Hawaii, canine distemper in wild carnivores, and sarcoptic mange in many wild animal species. Chytridiomycosis, a fungal disease of amphibians spread globally by human activity, has caused the decline of at least 501 species and probable extinction of 90 of these (Scheele et al. 2019). White nose syndrome, a fungal disease introduced to North America, has caused the deaths of millions of insectivorous bats and catastrophic declines in at least 4 species (Blehert et al. 2009; Frick et al. 2010). Beak and feather disease virus (BFDV) has caused deaths following introduction to captive and wild populations of critically endangered orangebellied parrots (Neophema chrysogaster) (Peters et al. 2014). The iconic koala (Phascolarctos cinereus) is affected by Chlamydia, Koala retrovirus, and sarcoptic mange. Important drivers of infectious disease emergence in wildlife include exposure to novel infectious pathogens and changes in transmission dynamics in a natural host. These manifest most commonly through atypical intraspecific and interspecific contact events, including those mediated through mechanical vectors such as equipment. For instance, considerable evidence supports the global movement of living and mechanical vectors of Batrachochytrium dendrobatidis (Bd) as the cause of decline of at least 501 amphibian species (Scheele et al. 2019). Such movement fostered atypical contact between populations of amphibians in which Bd was native and populations that were evolutionary naïve. Atypical intraspecific and interspecific contact events commonly occur with intensive conservation interventions such as those conducted in an emergency (e.g., supplementary feeding, artificial refuge installations, translocations, captive breeding), because these activities can involve the aggregation of animals in time and space, enabling disease spillover and transmission through increased animal to animal contact. Some conservation interventions remove spatial and temporal barriers to infectious disease transmission between species and populations, for instance, locating captive breeding facilities far from the natural distribution of a species and where direct or indirect contact with domestic and wild animals might occur. These create an alignment of opportunity for spillover of infectious pathogens into new hosts, as seen in zoonotic disease emergence in humans (Plowright et al. 2017). While the likelihood of disease emergence for any single conservation intervention may not be high, the consequence of such an event can be severe. For example, BFDV emerged in 2 of only 3 captive breeding programs for threatened parrots in Australia following likely introduction into the captive population (Peters et al. 2014). Repeated introductions of BFDV, a listed key threatening process since 2001, have occurred in the orange-bellied parrot recovery program in the past decade (Das et al. 2020), highlighting failings in contemporary recovery programs to manage infectious disease