Tamaš Petrović1, Milanko Šekler2, Zoran Debeljak2, Vladimir Polaček1, Dejan Vidanović2, Ljubiša Veljović3, Sava Lazić1, Dejan Bugarski1, Gospava Lazić1, Diana Lupulović1, Budimir Plavšić4, Nenad Petrović4
1 Naučni institut za veterinarstvo „Novi Sad“, Novi Sad, 2 Veterinarski specijalistički institut Kraljevo, Kraljevo, 3 Naučni institut za veterinarstvo Srbije, Beograd, 4 Uprava za veterinu, Ministarstvo poljoprivede i zaštite životine sredine, Beograd
E-mail: tomy@niv.ns.ac.rs
dr. Tamaš Petrović
Naučni institut za veterinarstvo “Novi Sad”
Nakon pojave BKK u Bugarskoj i Makedoniji, na temelju rizika ulaska BKK u Srbiju, Uprava za veterinu je povećala aktivni nadzor zdravstvenog statusa goveda na području južne Srbije. Nakon prve kliničke sumnje na BKK 4. lipnja 2016. godine u selu Ljiljance, općina Bujanovac, prvi slučaj bio je laboratorijski potvrđen u Veterinarskom specijalističkom institutu Kraljevo 7. lipnja 2016. godine. Prva odluka o označavanju inficirane zone općine Bujanovac i okruga Pčinjski kao zone nadzora donešena je 8. lipnja 2016. godine.
Temeljeno na postojećim pravilima procedure u kriznim situacijama, utvrđen je hijerarhijski sustav u procesu donošenja odluka i provođenju mjera prevencije, ranog otkrivanja, praćenja i eradikacije bolesti. Nacionalni krizni centar smješten u Upravi za veterinu, regionalni krizni centar u Veterinarskom specijalističkom institutu Niš, te lokalni krizni centri u pet okruga na jugu Srbije, uspostavljeni su prije prve pojave bolesti u Srbiji, 1. lipnja 2016. godine. Dodatno, odmah nakon prve kliničke sumnje na BKK, 7. lipnja je na nacionalnoj razini formiran ekspertni tim u kojemu su bili veterinarski epidemiolozi, laboratorijski dijagnostičari i članovi Uprave za veterinu. Ekspertni tim, kao i nacionalni i regionalni krizni centri, bili su u trajnoj komunikaciji, počevši od prvog slučaja izbijanja bolesti, bilo kroz konvencionalne dnevne sastanke ili online kroz internetsku komunikaciju zahvaljujući kojoj su svi članovi tima u svakom trenutku bili upoznati sa najsvježijim informacijama i gdje su dokumentacija i mišljenja eksperata komunicirani u realnom vremenu, 24 sada dnevno. Kasnije, kako se bolest širila, uspostavljani su novi regionalni i lokalni krizni centri. Zbog brzog širenja bolesti, utjecaja na čitavu društvenu zajednicu i potrebe za uključivanjem više ljudi posebice državnih snaga i resursa, kao dio Vlade Republike Srbije, osnovano je Operativno zapovjedništvo za koordinaciju provedba mjera za prevenciju, kontrolu i iskorjenjivanje BKK. Operativno zapovjedništvo sastajalo se tjedno, a bilo je odgovorno za koordinaciju nabavke vakcine i koordinaciju aktivnosti veterinarske službe sa aktivnostima lokalnih zajednica, policije i vojske koji su također, kroz svoje zapovjedništvo, bili uključeni u kontrolu bolesti.
Na početku izbijanja bolesti, u kontroli bolesti primjenjivano je samo rano otkrivanje i ‘stamping-out‘ metoda. U toj najranijoj fazi kontrole bolesti, primjenjivana je politika necijepljenja. Zbog dugog inkubacijskog perioda infekcije i prenošenja virusa vektorima, u tom je periodu provođena čak i brza laboratorijska dijagnostika i ‘stamping-out‘ procedura za čitava stada sa utvrđenom inficiranom životinjom – unutar vremenskog okvira od samo 48 do 72 sata. Restriktivne mjere u transportu životinja nisu bile dovoljne za zaustavljanje prijenosa virusa. Nakon prvih 7 dana izbijanja bolesti, kada se broj slučajeva brzo povećavao u inficiranim okruzima te zbog iskustava kontrole BKK u Bugarskoj, ekspertni tim je odlučio uključiti strategiju vakcinacije za kontrolu BKK. Vladino Operativno zapovjedništvo prihvatilo je odluku ekspertnog tima, pa je OBP LSD vakcina uvedena u zemlju. Čitava zemlja bila je podijeljena na tri dijela:
- dio A (prva dva inficirana okruga čija je vakcinacija planirana sa 50.000 doza dobivenih od EU za hitnu vakcinaciju)
- dio B (ugroženi okruzi u blizini bugarske granice i oko Kosova i do otprilike 100-200 km od inficiranih okruga kao i najveće farme goveda u čitavoj zemlji – planirano za vakcinaciju sa 400.000 doza vakcine nabavljene od strane Uprave za veterinu do kraja lipnja 2016. godine) i
- dio C (regija oko Beograda, dijelovi središnjeg i sjeveroistočog dijela Srbije, sjeverni dijelovi Srbije – planirano za vakcinaciju sa dodatnih 600.00 doza vakcine nabavljene od strane Uprave za veterinu, tijekom srpnja i kolovoza 2016. godine).
Mjere za kontrolu bolesti su uključivale: ‘stamping-out‘ proceduru za sva goveda u stadu sa potvrđenim slučajem BKK, neovisno o kategoriji, dobi i zdravstvenom statusu životinja, uništavanje proizvoda životinjskog podrijetla, neškodljivo uklanjanje lešina, nusproizvoda i otpada, dezinfekciju i dezinsekciju, kontrolu vektora, zabranu transporta životinja i intenzivni aktivni nadzor u inificiranoj i zaštićenoj zoni. Kako je donešena odluka o vakcinaciji goveda u čitavoj Republici Srbiji vakcinom temeljnoj na Neethling soju, mjere za borbu protiv bolesti su redefinirane. U slučaju pojave bolesti u nevakciniranom stadu, provođena je eutanazija i neškodljivo uklanjanje svih goveda, neovisno o kategoriji, dobi i zdravstvenom statusu životinja. Nakon provođenja vakcinacije, u slučajevima ako su se klinička manifestacija i laboratorijske potvrde bolesti povećavale u prethodno vakciniranom stadu i ako je prošlo više od 28 dana nakon vakcinacije, samo klinički bolesne životinje su eutanazirane i neškodljivo uklonjene (djelomična eutanazija). Ostale životinje iz takvog stada bile su pod aktivnim nadzorom veterinarske službe.
Nakon pojave BKK u Srbiji, tri veterinarska instituta – VSI Kraljevo u Kraljevu, NIVS u Beogradu i NIV-NS u Novom Sadu – određeni su za laboratorijsku dijagnostiku BKK. Protokol za uzorkovanje i transport uzoraka, kojeg je napravio ekspertni tim, izdan je u prvom tjednu nakon pojave bolesti. Laboratorijska dijagnostika slučajeva BKK bila je temeljena na otkrivanju virusa u uzorcima biopsata kožnih čvorića i EDTA uzorcima krvi (obavezni uzorci) te u nekim slučajevima iz brisa nosa (dodatni uzorci). Za laboratorijsku dijagnostiku BKK, u laboratorije je uvedena real-time PCR metodologija (protokol Bowden i sur., 2008.) kao i konvencionalna PCR metodologija (protokol Ireland i Binepal, 1998.) nešto prije prve pojave bolesti. Obje ove metode su capripoxvirus specifične, ali kako u Srbiji nema boginja ovaca i goveda, nije bilo potrebe za uvođenjem capripoxvirus diferencirajućih metoda. Većinom, spomenuta real-time PCR metoda, kao visokoosjetljiva, brza i robusna metoda primijenjena je za detekciju svih slučajeva BKK.
Zbog mogućnosti blagih ili sustavnih post-vakcinalnih reakcija u vakciniranih životinja, nakon uvođenja vakcinacije goveda protiv BKK, primjena novih dijagnostičkih procedura bila je neophodna za diferencijaciju terenskog od vakcinalnog (Neetling) virusnog soja. Za tu namjenu, u laboratorije je uveden tzv. nested PCR protokol sa RFLP analizom (opisao Menasherow i sur., 2014.). Kako je ovaj (nested PCR / RFLP) protokol dugotrajan i sklon unakrižnoj kontaminaciji, razvijen je te u laboratorije kao ‘in-house‘ metoda uveden real-time PCR DIVA protokol radi razlikovanja terenskog i vakcinalnog soja.
U konačnici, izbijanje BKK u Srbiji rezultiralo je sa 221 epizootijom sa 257 slučaja, 699 eutanaziranih i neškodljivo uklonjenih životinja te 1.080.398 vakciniranih životinja počevši od prve pojave bolesti 4. lipnja do 23. rujna 2016. (111 dana).
Tijekom epizootije BKK, čitava veterinarska služba pokazala se visoko kompetentnom i sposobnom rješavati emergentne situacije te uspješno kontrolirati bolest.
Ključne riječi: BKK epizootija, dijagnostika, kontrolne mjere, Srbija
Experiences of diagnosing and control of lumpy skin disease in Serbia
Tamaš Petrović1, Milanko Šekler2, Zoran Debeljak2, Vladimir Polaček1, Dejan Vidanović2, Ljubiša Veljović3, Sava Lazić1, Dejan Bugarski1, Gospava Lazić1, Diana Lupulović1, Budimir Plavšić4, Nenad Petrović4
1 Scientific Veterinary Institute „Novi Sad“, Novi Sad, Serbia
2 Veterinary Specialized Institute “Kraljevo”, Kraljevo, Serbia
3 Scientific Veterinary Institute of Serbia „Belgrade“, Belgrade, Serbia
4 Veterinary Directorate, Ministry of Agriculture and Environmental Protection, Belgrade, SerbiaE-mail: tomy@niv.ns.ac.rs
Tamaš PetrovićPhD
Scientific Veterinary Institute „Novi Sad“L umpy skin disease (LSD) is a viral disease of cattle caused by capripoxvirus, transmitted mainly by mechanical vectors, and characterised by severe losses, especially in naive animals. LSD is characterised by fever, nodules on the skin, mucous membranes and internal organs, emaciation, enlarged lymph nodes, oedema of the skin, and sometimes death. The disease mainly spread to infection-free areas by transport of infected animals and by vectors. LSD is endemic in many African and Asian countries, and Middle East including Turkey, but it is exotic in Europe. In just one year period, starting from August 2015, the disease was spread from Turkey to the territory of 6 countries on Balkan Peninsula (Greece, Bulgaria, FYR Macedonia, Serbia including Kosovo, Montenegro and Albania).After the appearance of the LSD in Bulgaria and FYR Macedonia, based on the risk of LSD introduction in Serbia, the Veterinary Directorate increased the active surveillance of the health status of cattle in the territory of southern Serbia. After the first LSD clinical suspicion on 4th of June in settlement Ljiljance, municipality Bujanovac, the first case was laboratory confirmed in VSI Kraljevo on 7th of June 2016. The first decision on designation of the infected zone of Municipality of Bujanovac, and Pčinjski District as the surveillance zone was done on 8th of June.
Based on the Rules of procedure in crisis situations, the hierarchical system within the decision-making process, and implementation of measures of prevention, early detection, monitoring and eradication of disease was established. The national crisis centre, located in the Veterinary Directorate, the regional crisis centre in Veterinary Specialized Institute “Nis”, and the local crisis centres in the five Districts of south part of Serbia, were established before first onset of disease in Serbia on 1 st of June 2016. In addition, immediately after the first clinical suspicion on LSD, on 7th of June, the expert’s team was formed at the national level from the veterinary epidemiologists, laboratory diagnosticians and members of Veterinary Directorate. The expert’s team, as well as the national and regional crisis centres, were in permanent session, starting with the first case of the outbreak of the disease, whether through conventional daily meetings, either on line through the web-based communication system, through which were all team members become familiar with up to date information at all times, and where the communication of expert opinions and documentation were performed in real time each day during 24 hours. Later on, as the disease spread, the new regional and local crisis centres were established. Due to the fast spread of disease, influence on the whole society and necessity of inclusion of more human but especially legal power and resources, as part of the Government of the Republic of Serbia the Operational Headquarters for coordinating the implementation of measures to prevent, control and to eradicate LSD was established. The Operational Headquarters meets on weekly basis, and was responsible for coordination of purchase of vaccine and coordination of activities of veterinary service with activities of local communities, police and army that were also, through this Headquarters, included in control of disease.
At the beginning of the outbreak, only the early detection and stamping out method was used for control of the disease. In that very early phase of disease control, non-vaccination policy was used. Due to the long incubation period of the infection and transmission of the virus by vectors, even the fast laboratory diagnostic and stamping out procedure for the whole herds with detected infected animal, in a time frame of only 48 to 72 hours, was on place during that period, the restrictive measures for animal movement were not enough to stop the virus transmission. After the first 7 days of LSD outbreak, when new cases were rapidly arisen all over the infected district, and due to the experiences of LSD control in Greece and Bulgaria, the expert group was decided to include the vaccination strategy to control LSD. The Governmental Operational Headquarters accepted the decision of the expert group and OBP LSD vaccine was introduced in the country. The whole country were divided in three parts: part A (two first infected districts planned to be vaccinated with 50,000 doses received from EU for emergent vaccination), part B (endangered districts that are near Bulgarian border and around Kosovo, and up to approximately 100 – 200 km from infected districts, as well as biggest cattle farms all over the country – planned to be vaccinated with 400,000 vaccine doses purchased by Veterinary Directorate until the end of June 2016), and part C (regions around Belgrade, parts of central and north-eastern part of Serbia, and northern part of Serbia – planned to be vaccinated with additional 600,000 vaccine doses purchased by Veterinary Directorate, during July and August 2016).
The measures for control of disease included: stamping out procedure of all cattle in herd with confirmed case of LSD, regardless of category, age and health status of animals; destruction of animals products; safe disposal of carcasses, by-products and waste; disinfection and disinfestation; control of vectors; animal movement restriction and intensive active surveillance in infected and protection zone. Since the decision was made for vaccination of cattle in the entire Republic of Serbia with vaccine based on Neethling strain, measures to combat the disease were redefined. In the case of the occurrence of the disease in unvaccinated herd, the euthanasia and safe removal of all cattle in herd was performed, regardless of category, age and health status of animals. After conducting vaccination, in case if the clinical manifestation and laboratory confirmation of the disease arose in the previously vaccinated herd, and if more than 28 days passed after the vaccination, only the clinically sick animals were euthanized and safely disposed (partial euthanasia). The rest of the animals in such a herd was under the active supervision of the veterinary service.
After the occurrence of LSD in Serbia, three veterinary institutes, VSI Kraljevo in Kraljevo, NIVS in Belgrade and NIV-NS in Novi Sad were designated for the laboratory diagnosis of LSD. Protocol of sampling and samples transportation, prepared by the expert group was issued in the first week after the disease occurrence. The laboratory diagnosis of LSD cases was based on virus detection in biopsy samples of skin nodules and EDTA blood samples (obligatory samples) and in some cases nasal swabs (additional samples). For laboratory detection of LSDV, the real-time PCR methodology (protocol of Bowden et al., 2008), as well as conventional PCR methodology (protocol of Ireland end Binepal, 1998), were introduced in the labs shortly before the first onset of disease. Both of these methods are capripox virus specific, but since Serbia is free of sheep and goat pox, there was no need to include capripox virus differential methods. Mostly, the mentioned real-time PCR methodology, as highly sensitive, fast and robust method was used for detection of all LSD cases.
Due to the possibility of mild or systemic post-vaccination reactions in vaccinated animals, after the implementation of the vaccination of cattle against LSD, application of new laboratory diagnostic procedures was necessary for differentiation of field from vaccine (Neetling) virus strain. For that purpose, the nested PCR protocol with RFLP analysis (described by Menasherow et al., 2014) was introduced in labs. Since the nested PCR / RFLP protocol is time consuming and prone to cross contamination, the real-time PCR DIVA protocol to distinguish field for vaccine LSD strain is developed and introduced in the labs as in house method.In total, LSD outbreak in Serbia in 2016 resulted with 221 outbreaks with 257 cases, 699 destroyed and safely disposed animals, and 1,080,398 vaccinated animals starting from first occurrence of disease on 4th of June until 23rd of September 2016 (111 days).
During LSD outbreak, the whole veterinary service showed that is highly competent and capable to deal with animal disease emergent situations and to successfully control the disease.
Keywords: LSD outbreak, diagnostic, control measures, Serbia
Acknowledgments: This work is supported by Veterinary Directorate, Ministry of Agriculture and Environmental protection, and partly conducted within the project TR31084 funded by the Serbian Ministry of Education, Science and Technological development.
