Article history: Received: 19-06-2017, Accepted: 08-09-2017, Published online: 04-10-2017
Corresponding author: Fayssal Bouchemla
E-mail: email@example.comCitation: Bouchemla F, Popova OM, Agoltsov VA (2017) Analysis of spatial dynamic of epizootic process of bluetongue and its risk factors, Veterinary World, 10(10): 1173-1183.
Aim: The study was undertaken to find out the spatial dynamic occurrence and patterns of the global spread of bluetongue (BT) disease for the period from 1996 to 2016, as well as the assessment of the risk of occurrence and its spread in 2017-2018.
Materials and Methods: Outbreaks (serum samples were collected from clinically healthy as well as suspected animals in infected points) were confirmed and reported officially by veterinary departments which represent different geographical regions in the world to World Organization for Animal Health. These reports explained that ELISA and polymerase chain reaction were used to identify the BT disease, taking in the account number of infected, dead animals, and focus of BT infection in all susceptible animals from 1996 to 2016. Once conventional statistical population was defined (an observational study), we had classified data as well as possible to answer to our aim, using descriptive statistics methods, including the test of the relationship between different epizootiological indicators.
Results: The spatial dynamic study of BT's occurrence and its spread in the world over the two past decades was presented by different epizootic indicators. The given analysis includes assessment and measurement of risk factors. It was built too, regression models, and allowed to put different forecasts on the different epizootic indicators in the years 2017-2018 by the extrapolation method. We had also determined that, in 2017, BT continues to spread with the total expectancy of 3.4 focus of infection (number of diseased animals in a single unfavorable point) and mortality of about 26 %; these rates tend to decrease in 2018. At abused points by BT, up to 78.4% of animals are mixed (more than one type) and in 21.6% - uniform. By this way, the relative risk of the incidence of appearance-abused points in mixed households has 3.64, which might be considered higher for the BT dissemination. Moreover, between the enzootic index and other epizootiological indicators had revealed an inverse correlation, i.e., to an increase in the level of enzootic index among the cattle population would be formed population less sensitive to BT. Cluster analysis was done, which had demonstrated the zoning of risk levels in the world and the occurrence of the disease intensity in the period 1996-2016 years. Then, assess connection degree of the dynamic of BT tension with geographical and socioeconomic conditions background 0.66 and 0.68, respectively.
Conclusion: It is important to define a variety of BT risk factors and assess their influence on BT occurrence. However, the most important is to define the overlapping coinfluence between them that cause serious losses. To have an out of BT territory needs to make an emphasis of co-influence of risk factors on this zone. Was predicted a continue hits of disease in the next year with weight moderation through one year. Far from statists, to assess the given forecast may have a serious variety, taken in account problems of actual climate change in the world.
Keywords: bluetongue, extrapolation, outbreaks, regression model, risk factors.
1. Bouchemla, F. (2016) Features of the epizootic process of bluetongue in various geographical areas. Author's abstract of can. Dis. Vet. Sci. Kazan., 190: 5-12.
2. Guichard, S., Guis, H., Tran, A., Garros, C., Balenghien, T. and Darren, J. (2014), Worldwide niche and future potential distribution of Culicoides imicola, a major vector of bluetongue and African horse sickness viruses. PLoS One, 9: e112491. [Crossref]
3. Kononov, A.V., Sprygin, A.V., Fiodorova, O.A., Babin, Y.Y., Elatkin, N.P., Mathieu, B. and England, M.E. (2014) Culicoides bitings midges (Diptera: Ceretopogonidae) in various climatic zones in Russia and adjacent lands. J. Vector Ecol., 39: 306-315. [Crossref] [PubMed]
4. Mahmoud, M.A. and Khafagi, M.H. (2014) Seroprevalence of bluetongue in sheep and goats in Egypt. Vet. World, 7(4): 205-208. [Crossref]
5. Pany, S.S., Biswas, S.K., Chand, K., Mohanty, N.N., Sarangi, L.N., Mondal, B. and Panda, H.K. (2016) Antigenic evidence of bluetongue virus from small ruminant population of two different geographical regions of Odisha, India. Vet. World, 9(3): 304-307. [Crossref] [PubMed] [PMC]
6. Bouchemla, F. and Agoltsov, V.A. (2015) Retrospective analysis and assessment of the bluetongue epizootic situation. Naytch. Jizn., 1: 139-142.
7. Bouchemla, F. and Agoltsov, V.A. (2014) Analysis of the epizootic situation bluetongue in the Mediterranean countries. Ucheniye Zap. KGAVM, 219: 62-69.
8. Tabachnick, W.J. (1996) The genetics of Culicoides variipennis and the epidemiology of bluetongue disease in North America. Annu. Rev. Entomol., 45: 20-40.
9. Chand, K., Biswas, S.K., Pandey, A.B., Muthuchelvan, D. and Mondal, B. (2015) Bluetongue in India: A review. Adv. Anim. Vet. Sci., 5: 605-612. [Crossref]
10. OIE. Available from: http://www.oie.int/wahis_2/public/wahid.php/Countryinformation/Reporting. Accessed on 20-05-2017.
11. Velthuis, A.G.J., Saatkamp, H.W., Mourits, M.C.M., de Koeijer, A.A. and Elbers, A.R.W. (2010) Financial consequences of the Dutch bluetongue serotype 8 epidemics of 2006 and 2007. Prev. Vet. Med., 93: 294-304. [Crossref] [PubMed]
12. Zientara, S., Sailleau, C., Viarouge, C., Hoper, D., Beer, M., Jenckel, M., Bernd, H., Aurore, R., Labib, B.K., Aurore, F., Damien, V. and Emmanuel, B. (2014) Novel bluetongue virus in goats, Corsica, France, 2014. Emerg. Infect. Dis., 20(12): 2123-2125. [Crossref] [PubMed] [PMC]
13. Bluetongue in the Russian Federation, Rosselkhoznadzor. (Electronic Resource) Available from: http://www.fsvps.ru/fsvps-docs/ru/iac/2011/files/asf_2011-12-27.pdf. Accessed on 28-09-2016.
14. Bakulov, I.A., Knieze, A.V., Strizhakov, A.A., Dmitrenko, N.V. and Filomatova, V.A. (2007) Methodological recommendations on the management of epizootological monitoring of exotic especially dangerous and little known animal diseases. Raashn Gnu VNIIVVIM, Pokrov. p79.
15. OIE. (2014) Bluetongue, Manual of Diagnostic Tests and Vaccines for Terrestrial Animals, Part 2. Vol. 1. Ch. 2.1.3. OIE, Paris.
16. Ganter, M. (2016) Bluetongue disease-global overview and future risks. Small Rumin. Res., 118: 79-85.
17. Johnson, D.J. (2011) Identification of new United States bluetongue types. Proc. Am. Anim. Health A., 111: 209-210.
18. Kirkland, P.D. (2002) Bluetongue virus, vectors and surveillance in Australia-the current situation and unique features. Vet. Ital., 40(3): 47-50.
19. Rossi, S., Gibert, P., Breard, E., Moinet, M., Hars, J., Maillard, D., Wanner, M., Klein, F., Mastain, O., Mathevet, P. and Bost, F. (2010) Circulation et impact des virus de la fievre catarrhale ovine (FCO) chez les ruminants sauvages en France. Bull. Epidemiol., 35: 27-32.
20. Arenas-Montes, A.J., Arenas, A., Garcia-Bocanegra, I., Mertens, P., Batten, C. and Nomikou, K. (2013) Serosurveillance of orbiviruses in wild cervids from Spain. Vet. Rec., 172: 508-509. [Crossref] [PubMed]
21. Bouchemla, F. and Agoltsov, V.A. (2015) Guidelines guide to diagnostics, prevention and control measures against the bluetongue. Vet. Dep. Saratov Region, 58: 33.
22. Casaubon, J., Chaignat, V., Vogt, H.R., Michel, A.O. and Thuer, B. (2013) Survey of bluetongue virus infection in free-ranging wild ruminants in Switzerland. BMC Vet. Res., 9: 166. [Crossref] [PubMed] [PMC]
23. FAO Statistical Yearbook. Available from: http://www.fao.org/economic/ess/ess-publications/lannuaire-statistique/fr/#.WT0vmvnyjIU. Accessed on 01-02-2017.
24. Lorca-Oro, C., Lopez-Olvera, J.R., Ruiz-Fons, F., Acevedo, P., Garcia-Bocanegra, I., Oleaga, A., Gortazar, C. and Pujols, J. (2014) Long-term dynamics of bluetongue virus in wild ruminants: Relationship without breaks in livestock in Spain, 2006-2011. PLoS One, 8: e100027. [Crossref]
25. Miller, R.S., Farnsworth, M.L. and Malmberg, J.L. (2013) Diseases at the livestock-wildlife interface: Status, challenges, and opportunities in the United States. Prev. Vet. Med., 110: 119-132. [Crossref] [PubMed]
26. Pudupakam, R.S., Raghunath, S., Pudupakam, M. and Daggupati, S. (2017) Genetic characterization of the non-structural protein-3 gene of bluetongue virus serotype-2 isolate from India. Vet. World., 10(3): 348-352. [Crossref] [PubMed] [PMC]
27. Ruiz-Fons, F., Sanchez-Matamoros, A., Gortazar, C. and Sanchez-Vizcaino, J.M. (2014) The role of wildlife in bluetongue virus maintenance in Europe: Lessons learned after the natural infection in Spain. Virus Res., 182: 50-58. [Crossref]28. Zientara, S. (2010) Historique des introductions successives de la FCO en Europe. Bull. Epidemiol., 35: 1-4.