17 September 2010 - African Swine Fever (ASF) is a viral infection of pigs transmitted mainly through the oro-nasal route after contact with infected pigs, through feeding on virus-containing pork products (e.g. swill and garbage waste) or through infected Ornithodoros tick bites. Domestic pigs and European wild boar are equally susceptible to ASF.
Following the first disease report in Georgia, ASF progressively spread north- and westward across the Caucasus and southern Russian Federation following trade routes infecting mainly backyard holdings, and occasionally wild boar. Outbreaks of ASF have now been reported within few kilometres of the Ukrainian border. Maintenance of this highly lethal ASF strain in pigs—in the absence of Ornithodoros ticks and animal reservoirs—is believed to largely relate to stored infected pork products that act as reservoirs, causing the disease to reappear whenever pigs are fed infected leftovers.
The critical question to ask is how ASF may find its way to non-infected countries in Eastern Europe, particularly Ukraine, but also Asia. Introduction through infected wild boar seems highly unlikely given the high lethality of the pathogen, the high fragmentation of suitable habitats, the low density of wild boars, and the absence of free-roaming pigs in eastern Ukraine.
The most probable path of introduction (and further spread) would be through the (mostly informal) movement of contaminated pork products, transported for personal consumption or smuggled for trade purposes, followed by (1) swill/scrap-feeding to pigs or (2) leftovers discarded in communal waste sites. Introduction is most likely to happen in smallholdings (i.e. backyards and small commercial farms), where awareness, biosecurity and compliance to animal regulations are usually minimal. Moreover, prevention and response at smallholding units is a most challenging task for national veterinary services. Despite the high risk posed by ASF, not enough is known about most aspects of village-level pig keeping, slaughtering, processing and trade.
Following analyses to explore some general patterns in the distribution of pigs, as well as swine production systems and wild boar in Eastern Europe, a multidisciplinary FAO team was fielded in July 2010 to Lugansk Oblast, Ukraine’s easternmost province, to gather information from pig keepers, middlemen, butchers, wild boar-related stakeholders and veterinary and public health authorities on the following: (a) the formal and informal movements and marketing of pigs and pork products and consumption patterns; (b) the pig rearing practices at smallholder level, focusing on the practice of risky behaviours, e.g. home-slaughtering, swill feeding, reporting of suspected cases; (c) the challenges for the veterinary services, e.g. border and movement control, farm registration, animal identification and traceability, and disease detection; and (d) wild boar hunting practices and management.
This improved understanding of pig-related sectors will allow:
- To identify the risky behaviours and points in the market chain that are most vulnerable to ASF, and to assess their role in the potential introduction, spread and persistence of the disease;
- To build a village-level ASF risk assessment/risk mitigation module/guidelines for the region, evaluating all aspects and actors;
- To better prepare veterinary services and local communities in ASF prevention, detection and response.
Detailed results and analysis will soon be published in the EMPRES Bulletin 36.
Figure 1. Formal market chains for live pigs and carcasses in Eastern Ukraine