How Czech Republic Eradicated African Swine Fever
Elizabeth VL Hmangaihzuali1, Vanlalngilneii Ralte2, Lalrinkima3
1Assistant Professor, Department of Veterinary Anatomy, R.R. College of Veterinary and Animal Science, Deoli, Rajasthan
2Assistant Professor, Department of Veterinary Physiology & Biochemistry, R.R. College of Veterinary and Animal Science, Deoli, Rajasthan
3Assistant Professor, Department of Veterinary Pathology, Khalsa College of Veterinary and Animal Sciences, Amritsar, Punjab
African swine fever (ASF) is a viral disease of swine leading to high almost upto 100% mortality in domestic and wild pigs. The diseases has been listed into the category as “notifiable disease” by the World Organization for Animal Health (OIE). It causes important economic losses that are unavoidable in the absence of an effective vaccine and the available methods of diseases control are the quarantine of the affected area and culling of the infected animals.
India report the first outbreaks of African swine fever virus in Assam and Arunachal Pradesh states on February 2020. By June 2021, the disease has spread to other parts of Northeastern states such as Meghalaya, Mizoram, Manipur and Nagaland. Till date pig’s farmers in Mizoram are facing problems. Recently, Czech Republic declared that they are free from African swine fever.
The first ASF positive carcass was found in Príluky, Zlín district, in an inhabited area of the Czech Republic in June 2017. This epidemic focal incursion of ASFV involved a limited wild boar population and progressed slowly in space. Since its first introduction until December 2017, the disease spread slowly at a rate of 0.5 km/month, despite the high wild boar density (8– 10/km2). The infected area was located 30 km from the Slovak border and 80 km from both the Austrian and the Polish borders. From 2014 to March 2019, 4,296 wild boars found dead were tested for ASF of which 211 tested positive. The last ASF polymerase chain reaction positive case in hunted wild boar was found in February 2018 and the last two positive cases in carcasses probably dead 4–5 months before discovery were identified in April 2018.
Nationwide passive surveillance started in 2014 and was applied to all dead pigs found throughout the country. It proved to be a key factor in early detection of ASF that enabled an immediate and effective response. The strategy for successful eradication was based on the definition of different wild boar management zones according to a certain level of risk into three areas:
- An infected area divided into (1a) zone with low risk and (1b) zone with high risk defined by a polygon of 159 km² estimated on wild boars’ year-long home range. In addition, fences were built within the high-risk zone to delimit an area of 57 km² where the total depopulation with high biosecurity measures was performed by policy snipers specially trained for hunting in biosecurity
- An intensive hunting area of 8,500 km² excluding the Zlín district on the outskirt of the low risk zone and
- The rest of the country
After first confirmation of ASF in June 2017, hunting was regulated firstly through a ban within the infected area, then it was allowed only in infected area of the low risk zone, then it shifted from the trapping of wild boar in the high risk zone to individual hunting in the same zone in the infected area. The measures and approaches used after the outbreak’s confirmation differed depending on the risk of infection. The success of ASF eradication in the Czech Republic relied on the management zones’ demarcation, enhanced passive surveillance of dead wild boars through intensive and systematic searching and removal of carcasses, a ban on driven hunting, motivation for hunters through financial rewards and compensation, high biosecurity during hunting and sampling collection in the infected area, disposal of hunted wild boars from the infected area to/selected//definite rendering plants, effective hunting in the infected area by snipers and awareness training campaigns and education of hunters, veterinary services and the public.
African swine fever can be controlled and eradicated through classical surveillance and control measures as demonstrated in the experiences of Czech Republic. Classical measures are based on disease control methods, including surveillance strategies, epidemiological investigation, tracing and culling of pigs in infected holdings in combination with strict quarantine and biosecurity measures on domestic pigs, holdings and the control of animal movement.
