Evaluation of the Presence of ASFV in Wolf Feces Collected from Areas in Poland with ASFV Persistence

Abstract

African swine fever (ASF), caused by a DNA virus (ASFV) belonging to genus Asfivirus of the Asfarviridae family, is one of the most threatening diseases of suids. During last few years, it has spread among populations of wild boars and pigs in countries of Eastern and Central Europe, causing huge economical losses. While local ASF occurrence is positively correlated with wild boar density, ecology of this species (social structure, movement behavior) constrains long-range disease transmission. Thus, it has been speculated that carnivores known for high daily movement and long-range dispersal ability, such as the wolf (Canis lupus), may be indirect ASFV vectors. To test this, we analyzed 62 wolf fecal samples for the presence of ASFV DNA, collected mostly in parts of Poland declared as ASF zones. This dataset included 20 samples confirmed to contain wild boar remains, 13 of which were collected near places where GPS-collared wolves fed on dead wild boars. All analyzed fecal samples were ASFV-negative. On the other hand, eight out of nine wild boar carcasses that were fed on by telemetrically studied wolves were positive. Thus, our results suggest that when wolves consume meat of ASFV-positive wild boars, the virus does not survive the passage through intestinal tract. Additionally, wolves may limit ASFV transmission by removing infectious carrion. We speculate that in areas where telemetric studies on large carnivores are performed, data from GPS collars could be used to enhance efficiency of carcass search, which is one of the main preventive measures to constrain ASF spread.

Not Just Pictures: Utility of Camera Trapping in the Context of African Swine Fever and Wild Boar Management

“…Wild boar but also wolves' movements have been described as the potential drivers of ASF spread by faces and/or mechanical transportation of the virus with mud on the paws [28,29]. Camera trap-based methodologies have been described to estimate (i) activity level (i.e., the proportion of the day that the population spend in movement) and daily distance travelled (i.e., day range) of wildlife.…”

Spatial proliferation of African swine fever virus in South Korea

“…To control the spread of ASFV, eradication programs, based on the rapid diagnosis, disposal, and slaughter of all animals in an infection zone, thorough cleaning and disinfection, surveillance, desensitization, and movement control measures, should be applied [ 9 , 10 ]. Ecologists have suggested that wild boar [ 11 ], wolves [ 12 ], ticks [ 13 ], synanthropic birds [ 14 ], feed houses [ 14 ], slaughterhouses [ 15 ], and wildlife in general [ 16 ] play a prominent role in the spread, infection, and maintenance of ASF [ 17 , 18 ]. The direction of epidemic waves can be observed and predicted based on disease vector habitats, movement range, and movement patterns [ 17 , 19 ].…”

Evaluation of the Effect of Hydrated Lime on the Scavenging of Feral Swine (Sus Scrofa) Carcasses and Implications for Managing Carcass-Based Transmission of African Swine Fever Virus

“…It is important to note that scavenging may help to reduce the pathogen burden by contributing to carcass breakdown and decomposition (Probst et al 2019; O'Neill et al 2020). For instance, scavenging of ASFV-contaminated wild boar carcasses by wolves reduces the environmental burden of the pathogen because the virus is degraded in the gastrointestinal tract (Szewczyk et al 2021). The use of hydrated lime is intended to be in addition to carcass removal, not in lieu of it.…”