Control and Elimination of Rabies in the Baltic States

Transcription

1 Nancy laboratory for rabies and wildlife WHO Collaborating Centre for Research and Management in Zoonoses Control OIE Reference Laboratory for Rabies European Union Reference Laboratory for Rabies European Union Reference Institute for Rabies Serology Nancy Laboratory for Rabies and Wildlife Control and Elimination of Rabies in the Baltic States Emmanuelle Robardet, Evelyne Picard-Meyer, Marianna Dobroštana, Ingrida Jaceviciene, Katrin Mähar, Zita Muižniece, Gediminas Pridotkas, Marius Masiulis, Enel Niin, Edvīns Olševskis, Florence Cliquet ESTONIAN VETERINARY AND FOOD LABORATORY & ESTONIAN, LATVIAN AND LITHUANIAN, FOOD AND VETERINARY SERVICE 26 th Rabies In the Americas meeting Fort Collins, Colorado, USA 4-8 October th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 1

2 THE BALTICS AND THEIR RABIE S HISTORY Topography relatively flat max 3m 4% of temperate forest Sylvatic rabies emerged in 195s-196s (European epidemic started in 194s) 199 Two principally infected species: Nyctereutes procyonoides Vulpes vulpes 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 2

3 RABIES CONTROL IN THE BALTICS Before 25: Various manual ORV field experimentations (area, frequency, bait, etc.) in Lithuania and Latvia 26 Following accession to the European Union in 24: Regular harmonised ORV plan in the three countries 25 Estonia and Latvia half territory Biannual campaigns (Spring and Autumn) On the whole territory since 26 Aerial distribution Some variations remain, including: Bait density Bait type Use of automatic device Rabigen (Virbac) Fuchsoral (IDT) Lysvulpen (Bioveta) 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 3

4 RABIES SURVEILLANCE Sampling scheme: In the whole country during all the year Assessment of rabies incidence Indicator animals Animals suspected of having rabies Animals having contaminated human beings Rabies diagnosis (FAT, RTCIT, PCR) Rabies diagnosis High chances to detect positive cases No sample size 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 4

5 ORV MONITORING Sampling scheme: Following each ORV (autumn and spring) in all vaccinated areas Evaluation of control strategy efficiency Seroconversion (ELISA test) Hunted foxes and raccoon dogs ( Healthy animals) Bait-uptake (Biomarker detection) Analysis of rabies antibodies Analysis of biomarker occurrence Sample size recommended: 4 animals per 1 km² annually (WHO, 213; EFSA,21) 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 5

6 N positive cases N dropped baits N positive cases N dropped baits N positive cases N dropped baits TEN YEARS OF SURVEILLANCE AND CONTROL Maximum infected area: km 2 SAG % of foxes POSITIVE CASES 38% of raccoon dogs Year and semester Maximum infected area: 64 km 2 SAD B19 SAD Bern Year and semester Year and semester Maximum infected area: 63 km 2 SAD B19 SAD Bern Time needed to reduce by 9% the number of positive detected cases (based from the maximum semi-annual incidence): 2 ORV campaigns in Estonia, 4 in Lithuania, and 8 in Latvia. 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 6

7 SURVEILLANCE OF RABIES Taking into account the total number of animals tested 24,919 animals tested in 1 years Decrease of the proportion of positive samples, as soon as the whole territory of each country was vaccinated. 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 7

8 SURVEILLANCE OF RABIES Maps provided by the Rabies Bulletin Europe website Last detected case: 211 in Estonia 212 in Latvia 213 in Lithuania 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 8

9 BAIT UPTAKE RATE Influence of the country (Latvia vs Lithuania vs Estonia) on the TTC rate? species (fox VS raccoon dog) season (autumn vs spring) year age (juvenile vs adult) for Estonian and Lithuanian data only GLM formulae: glm.nb(npos~species+year+country+offset(log(ntest)) Variable Group Estimate CI (95%) P-value (Wald test) a) Baltic states SPECIES Raccoon dog ; YEAR.4.23 ;.52 <.1 COUNTRY Latvia ; COUNTRY Lithuania ; <.1 b) Estonia and Lithuania AGE Juvenile ; SPECIES Raccoon dog ; YEAR.3.19 ;.5 <.1 COUNTRY Lithuania ;.121 <.1 c) Latvia 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October YEAR.4.3 ;.48 <.1

10 N positive cases N dropped baits N positive cases N dropped baits N positive cases N dropped baits BAIT UPTAKE RATE Maximum infected area: km 2 SAG Evolution of the bait uptake per country Year and semester Maximum infected area: 64 km 2 SAD B19 SAD Bern Year and semester Maximum infected area: 63 km SAD B19 SAD Bern Year and semester 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 1

11 BAIT UPTAKE RATE Evolution of the bait uptake per species As suggested by GLM analysis: TTC level increase over time, TTC level higher in Red foxes than in Raccoon dogs. 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

12 SEROCONVERSION RATE Influence of the country (Latvia vs Lithuania vs Estonia) on the Seroconverison rate? species (red foxes vs raccoon dogs) season (autumn vs spring) year age class (juvenile vs adult) for Lithuanian data only GLM formulae: glm.nb(npos~season+offset(log(ntest)) Variable Group Estimate CI (95%) P-value(Wald test) a. Baltic states SEASON Spring ; b. Lithuania AGE Juvenile ; c. Latvia No significant factors detected YEAR.5.29 ;.71 <.1 KIT Biorad ;.689 <.1 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

13 SEROCONVERSION RATE Evolution of the seroconversion rate per country Mean = 5% No specific pattern: Reliability of the ELISA tests used? Suggested by Knoop, 21; De Benedictis 212; Wasniewski; 214, etc.. 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

14 PHYLOGENETIC STUDY Central Europe (CE) and Serbian Fox phylogroup Bourrhy et al., th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

15 PHYLOGENETIC STUDY Weastern Europe (WE) phylogroup Bourrhy et al., 1999; Lojkic at al., 21; Mc Elihnney et al., th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

16 PHYLOGENETIC STUDY Eastern Europe (EE) phylogroup Bourrhy et al., 1999; Mc Elihnney et al., 26; Lojkic at al., 21; Turcitu at al., 21; Mc Elihnney et al., 211; Picard et al., 212; 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

17 PHYLOGENETIC STUDY North Eastern Europe (NEE) phylogroup Bourrhy et al., 1999; Vanaga et al, 23; Turcitu at al., 21; Picard et al., th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

18 PHYLOGENETIC STUDY East of Russia (C) phylogroup Kuzmin et al., 24; Picard et al., th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

19 PHYLOGENETIC STUDY 158 field rabies virus collected North Eastern Europe (NEE) phylogroup 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

20 PHYLOGENETIC STUDY 5 field rabies virus collected Western Russia (C) phylogroup 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October 215 2

21 PHYLOGENETIC STUDY 2 vaccine associated cases 1st case: Marten marten 28 in Lithuania SAD B19 strain identified (N gene) but ORV using Lysvulpen 2 nd case: Badger badger 213 in Latvia SAD B19 strain identified (N and G genes) but ORV using Lysvulpen First identification in two non target species 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

22 CONCLUSION ORV effective to eliminate the disease in the three countries. Possibility to improve the ORV effectiveness by adapting the method more on the raccoon dog biology? Concern on the reliability of the serological tests, but promising new ELISA kit recently evaluated. Risk of reintroduction highlighted by sporadic cases of the C lineage: need to continue vaccination belt on border areas. Vaccine induced rabies cases reported for the first time in two non target species. 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October

23 ACKNOWLEDGEMENTS Melanie Biarnais from the French Agency for Food, Environmental and Occupational Health & Safety, Kristīne Lamberga and Mārtiņš Seržants from the Food and Veterinary Service of Latvia, Ieva Rodze from Institute of Food Safety, Animal Health and Environment "BIOR, Rita Granta and Kristīne Grāve from Institute of Food Safety, Animal Health and Environment "BIOR. THANK YOU FOR YOUR ATTENTION! 26 th Rabies In the Americas meeting Control and Elimination of Rabies in the Baltic States Fort Collins, Colorado, USA 4-8 October