2. Disease control strategy

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1 APPENDIX 6 REPORT ON THE SITUATION OF FMD IN TURKEY Sinan Aktas 1. Introduction Foot-and-mouth disease (FMD) is economically the most important disease causing significant losses in Turkey. FMD continued to be endemic in Turkey where 48 outbreaks have been reported in FMDV serotypes (O, A and Asia 1) have been detected in Turkey during 2002, but no Asia 1 case reported since April The geographical situation of Turkey is always a risk factor for the dissemination of the contagious diseases mainly from the eastern and south-eastern neighbours. Turkey has increased its efforts to control illegal animal movements through borders. Although very strict measures have been implemented to prevent illegal animal movements, occurrence of illegal animal movements can not be ruled out totally. Especially the war in Iraq increased the risk of spread of diseases from Iraq and strains which are currently not present in Turkey can be introduced through the intensive movement of humans and animals. Animal movements within the country are also from east to the western parts of the country, where big consumption areas are located. National veterinary services are spending great efforts to control FMD in recent years. To increase the farmer participation in disease control programs, it was decided to charge farmers for FMD vaccines in This increased the budget of FMD Institute significantly and some major investments have been realised since than. 2. Disease control strategy Active surveillance and monitoring, vaccination, quarantine, restrictions on animal and animal product movements are being applied for the control of the disease. Our aim is to reach at least 70 % vaccination coverage in large ruminants. Based on regionalisation approach Turkey will continue to apply this control programme. The list of reported FMD outbreaks for 2001 and 2002 is given in Table 1. Types O and A was responsible for most of these outbreaks. Table 1: FMD Outbreaks in 2001 and A O Asia Total A O Asia Total January February March April May June July August September October November December Total

2 Outbreaks of FMD due to serotype Asia 1 was notified by OIE with an emergency case message on September 1999 in Iran. First occurrence of FMDV type Asia 1 was on October 1999 in Turkey. The disease was gradually spread westwards from Eastern Turkey near the Iranian border, in 1999 to Western Buffer Zone, in The last case of FMDV type Asia 1 was reported in April 2002 and since than no new case was detected. In addition no FMD outbreak has been reported in Thrace since June A total of 20 virus samples were sent to Pirbright Laboratory for the confirmation of our results and further characterisation. Genetic characterisation of FMD viruses in Sap Institute showed that type A viruses were related with A Iran 96 genetic group and type O viruses were still related with O Manisa. Antigenic characterisation studies showed that the virus strains currently circulating in Turkey can be covered by the vaccine strains of Sap Institute ( O Manisa 69 and A Ankara 98) Active surveillance Due to the critical situation in Iraq and presence of virus strains which can not be covered by vaccine strains currently in use in Turkey, active surveillance and monitoring activities have been intensified in the field especially in Eastern and South-Eastern borders of Turkey (Borders with Iran, Iraq and Syria). Based on the active surveillance carried out, there was no evidence of clinical FMD in Thrace. Main components of the active surveillance can be outlined as follows: Training of the technical personnel on FMD, mainly in the provinces close to the borders with Iran and Iraq. The farmers were encouraged to slaughter their animals in local slaughterhouses in Eastern and South-Eastern Anatolia to minimise the risk of spread of disease through long distance transport to the Western parts of Anatolia. Investigation of all susceptible cases, Disinfection of all vehicles at border inspection points. All animal markets were closed and strict restrictions were applied on the movements of livestock from these provinces, More strict security and traffic controls of the trucks on the overland routes, Regular controls and disinfection of the animal markets, 2.2. Vaccine Production The vaccine production has normally continued at the FMD Institute (SAP Institute). Vaccine production figures for 2002 are given in Table 2. A total of 24,600,000 monovalent cattle doses of FMD vaccine was produced in Table 2. Vaccine production in 2002 Vaccine strain Amount of vaccine produced (cattle doses) O Manisa 69 9,400,000 A Aydın 98 (homologue Iran 96) 6,000,000 Asia ,200,000 Total 24,600,000 81

3 Turkey has been investing significant amounts of money to increase the quantity and the quality of FMD vaccines which will in turn, contribute for the control of FMD in Turkey. The activities that can be mentioned in this context are as follows: Construction of a Class II clean room for the vaccine bottling area. Refurbishment of Control Department. Reduction of vaccine dose for cattle from 5 ml to 3 ml and for sheep from 2 ml to 1 ml. Introduction of 60 ml PET bottles. Turkey will continue to invest in FMD Institute to improve the conditions further. These investments will be: Refurbishment of Diagnosis Department. Installation of air filtration and air conditioning system for Control and Diagnosis Departments. Improvement of animal isolation unit. Installation of ultrafiltration and concentration system for the production of oil adjuvanted FMD vaccines. Repair of liquid waste treatment system Vaccination Program Spring Vaccination Programme The spring 2002 vaccination programme in Turkey was applied as follows: Thrace and Marmara Region Vaccination of all ruminants with a trivalent vaccine containing serotypes O, A and Asia 1 supplied by EU in Thrace region (Edirne, Tekirdag, Kırklareli, Istanbul and Canakkale) and with a trivalent vaccine produced by Sap Institute in provinces surrounding the Marmara Sea (Balıkesir, Bursa, Yalova, Kocaeli, Sakarya, Bilecik, Bolu, Anatolian parts of Istanbul and Canakkale) Black Sea Region Strategic vaccination of large ruminants with a trivalent vaccine in the coastal areas of Black Sea region. (Artvin, Giresun, Gumushane, Kastamonu, Ordu, Rize, Samsun, Sinop, Trabzon, Zonguldak and Bartin Provinces). Disease has not been reported for many years in this region In the other regions Vaccination of all large ruminants with a trivalent vaccine in the remaining parts of Anatolia. Spring vaccination campaign was completed within two months, March and April, in all Provinces. Spring vaccination figures are given in Table 3. Table 3. Results of spring vaccination campaign in Turkey in 2002 Provinces Programme Vaccination Percentage % Large Rum. Small Rum. Large Rum. Small Rum. Large Rum. Small Rum. EDIRNE 94, , ,856 97, KIRKLARELI 66, ,850 64, , TEKIRDAG 88, ,100 86,682 92, CANAKKALE 81, ,720 74, , ISTANBUL 64,080 66,200 55,426 38,

4 TOTAL 394, , , , ANATOLIA 7,509,556 5,255, Autumn Vaccination Program Thrace Region and Marmara Region In Thrace and Marmara Region vaccination of large ruminants with a trivalent vaccine Other regions Same as Spring 2002 vaccination campaign. Table 4. FMD vaccination figures for Autumn 2002 campaign Provinces Programme Vaccination Percentage % EDIRNE 94, KIRKLARELI 66,320 62, TEKIRDAG 88,500 78, CANAKKALE 81,378 62, ISTANBUL 64,080 58, TOTAL 394, , ANATOLIA 6,983,370 4,521, Vaccination strategy in The vaccination strategy for 2003 will be as follows: Application of routine mass vaccination using trivalent vaccine to all ruminants in the Thrace and Marmara regions, Application of routine mass vaccination using trivalent vaccine to all large ruminants in other regions, Application of strategic vaccination using trivalent vaccine to large ruminants in the Black Sea region, The vaccination campaign for Spring 2003 campaign has started at the beginning of March and will be completed at the end of April, the Autumn campaign will be carried out between September and October Five hundred thousand doses of trivalent FMD vaccine (Aftowax pur) to be used in Thrace was supplied by EU and was received on and was distributed to the provinces as follows: Table.5. Distribution of vaccine for Spring 2003 campaign in Thrace Province Vaccine Dose Tekirdağ Aftowax pur Aftowax Kırklareli Aftowax pur Canakkale Aftowax pur Istanbul Aftowax pur Edirne Aftowax pur Aftowax Total

5 3.2. Serosurveillance programme for 2003 Following the Spring 2003 vaccination campaign serosurveillance will be conducted both in Thrace and Anatolia. The serosurveillance plan for Thrace was discussed and agreed during the Research Group meeting in September 2002 in Izmir. According to this programme a total of 4800 sera will be collected and tested both by LPB-ELISA and 3ABC-ELISA as follows: One hundred villages were selected randomly from Thrace and from each village 24 cattle (8 animals <1 year of age, 8 animals between 1 and 2 years of age, 8 animals >2 years of age) and 24 small ruminants(8 animals <1 year of age, 8 animals between 1 and 2 years of age, 8 animals >2 years of age) will be bled 60 days post vaccination. These sera will be tested for the for the presence of antibodies following vaccination and infection. In order to carry out this serosurveillance reagents and some equipment are required and will probably be supplied by EUFMD. A serosurveillance was also planned for Anatolia and 200 hundred villages were selected randomly and from each village 24 cattle sera will be collected 28 days post vaccination (8 animals <1 year of age, 8 animals between 1 and 2 years of age, 8 animals >2 years of age) sera will be collected and tested both by LPB-ELISA and 3ABC-ELISA Vaccine quality control Tubingen QC results A trivalent FMD vaccine produced in Sap Institute was initially controlled at Pirbright Laboratory, UK. The vaccine was sterile and safe but in potency testing found to be negative for all three serotypes. Following this result a retesting was decided and Tubingen Laboratory, Germany, conducted this testing. The vaccine was safe and no toxicity due to the vaccine was detected. The result of potency testing was as follows; Type O: about 3 PD 50 Type Asia 1: about 1.5 PD 50 Type A: following challenge 3 out of 10 animals were protected. The control procedures and the summary results obtained in Sap Institute for the same vaccine were as follows: Routine in-process and final product controls applied in Sap Institute: Antigenic (CFT and/or ELISA) and infectivity (plaque test) titers of viruses used for vaccine preparation. Before clarification (dicalite filtration) After clarification Determination of 146S amount. Determination of inactivation kinetics. Sterility test. Safety test 84

6 In vivo (cattle) In vitro (elution test) Protection test. Challenge test: Full dose of every monovalent vaccine is applied to three FMD antibody negative cattle and challenged with homologous infective virus particles 21 days pv. Animals are bled at days 14 and 21 and tested for antibody levels by ELISA and/or VNT. Herd immunity test: At least 20 cattle vaccinated with trivalent vaccine and the antibody levels are determined at days 0 and 21 dpv Results of the tests applied to the vaccine that was sent to Tubingen : Type O: Batch No: Amount: cattle doses Sterility test result: sterile. Safety test result: safe. Challenge test: No Animal No Serum titer Day 14 Day 21 SNT ELISA SNT ELISA /128 1/3096 1/256 1/ /32 1/362 1/64 1/ /32 1/192 1/128 1/192 Virus Cont 8574 Neg. Neg. Neg. Neg. All three vaccinated animals were protected. Herd immunity test: 157 cattle vaccinated % protection level detected by ELISA (>1/100). Type A: Batch No: Amount: cattle doses Sterility test result: sterile. Safety test result: safe. Challenge test: No Animal No Serum titer Day 14 Day 21 SNT ELISA SNT ELISA /64 1/96 1/128 1/ /96 1/192 1/128 1/ /128 1/192 1/256 1/362 Virus Cont 8790 Neg. Neg. Neg. Neg. 85

7 All three vaccinated animals were protected. Herd immunity test: 193 cattle vaccinated % protection level detected by ELISA (>1/100). Type Asia1: Batch No: Amount: cattle doses Sterility test result: sterile. Safety test result: safe. Challenge test: No Animal No Serum titer Day 14 Day 21 SNT ELISA SNT ELISA /192 1/512 1/64 1/ /128 1/712 1/128 1/ /32 1/362 1/32 1/1024 Virus Cont. 602 Neg. Neg. Neg. Neg. All three vaccinated animals were protected. Herd immunity test: 20 cattle vaccinated 94.7 % protection level detected by ELISA (>1/100). FMD vaccine which was produced in Sap Institute was initially tested in Pirbright and because of the negative results obtained against all three serotypes, it was decided to repeat the test in Tubingen. Although the results obtained in Tubingen were better, when compared with the results obtained in Sap Institute, which were presented here in detail, there are still significant differences. The results obtained in Tubingen showed that only Type O component of the vaccine had a value of 3 PD 50. The results of Type A and Type Asia 1 were below 3 PD 50 and type A was the lowest. When we compare these results with our results it was a great surprise for us, because over the years our main problem was lower protection values which were obtained against type O vaccines. When we look at the results of the vaccines which were produced in 2002, it was clear that types A and Asia 1 vaccines performed better when compared with type O vaccines. Therefore we were expecting better results for types A and Asia 1. In addition there were no type Asia 1 outbreaks reported since April Tubingen is a very experienced institute and we believe that the results obtained in this institute are reliable. But following the results obtained in Sap Institute and the performance of the vaccine in the field on one hand and the results of Tubingen on the other hand, we are ready to work together closely with EUFMD for the control methods applied in Sap Institute and conduct another test together either in Turkey or in a European Laboratory for the vaccines to be produced for Autumn 2003 vaccination campaign. Turkey has been trying to continue to have a close relationship with EUFMD and be transparent and open as much as possible. Sap Institute gave all control results and we 86

8 believe that there is nothing to worry provided that current virus strains continue to circulate in Turkey. But we will definitely need assistance if exotic virus strains are introduced into Turkey due to the war in Iraq. Following the increase in the number of type A outbreaks in Turkey in 2002 Sap Institute has decided, to increase the amount of type A antigen in FMD vaccines, before the result of Tubingen was available. The amount of type A antigen has been increased 20-25% compared to those included in We are also trying to obtain virus purification and concentration system this year and therefore by the end 2003 we are hoping to store concentrated antigens and therefore overcome the problems of vaccine storage and also to produce oil-adjuvanted vaccine to prolong the duration of immunity. EUFMD can provide assistance to Turkey for the improvement of vaccine quality control in Turkey: Training for two personnel (one from Sap Institute and one from Bornova Institute) on the quality control of FMD vaccines in a well known laboratory. Conduct another vaccine control either in Turkey or in a European Laboratory with the participation of Turkish experts as soon as possible Bornova Vaccine Control Institute The construction of the laboratory in Bornova is almost completed and will be fully functioning in The laboratory in Bornova can now perform sterility tests. The experts of Bornova Institute and Sap Institute have currently been working to adopt the control methods for safety and potency. Initial studies will start for the vaccines to be produced for Autumn 2003 vaccination campaign. Bornova Institute will start routine controls of FMD vaccines in Contingency plans for the control of FMD in South-Eastern Turkey Turkey took the following measures to control all animal diseases, including FMD, which might be introduced to Turkey due to the increased movements because of the war in Iraq: A crises center has been established at the Ministry to follow all developments closely and take necessary measures for the control of animal diseases. The Provincial Directorates on the border areas were informed for the risks of disease spread. The Provincial Directorates on the border areas were supported by additional staff and vehicles for active surveillance. Turkey will try to stop the animal movements on the buffer zone in Iraq and if possible to control these animals for the presence of diseases. Samples will be taken for diagnosis. The animals will be slaughtered on the border area for human consumption. The infected animals will be destroyed. The vaccination programme has been started in March and will be completed as quickly as possible. 87