Veterinary World

Fayssal Bouchemla ¹, Olga Mikhailovna Popova ², Valerey Alexandrovich Agoltsov ¹

Affiliations
1 Department of Animal Disease, Veterinarian and Sanitarian Expertise, Saratov State Agrarian University (N.I. Vavilov), Saratov, RU
2 Department of Food Technology, Saratov State Agrarian University (N.I. Vavilov), Saratov, RU

Abstract

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 co-influence 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.

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Fayssal Bouchemla ¹, Valerey Alexandrovich Agoltsov ¹, Olga Mikhailovna Popova ², Larisa Pavlovna Padilo ³

Affiliations
1 Department of Animal Disease, Veterinarian and Sanitarian Expertise, Vavilov Saratov State Agrarian University, Saratov, RU
2 Department of Food Technology, Vavilov Saratov State Agrarian University, Saratov, RU
3 Department of Epidemiology and Risk Assessment , Saratov Research Veterinary Institute-Branch of Federal Research Center for Virology and Microbiology, Saratov, RU

Abstract

Aim: This study focuses on the spatial dynamic associated with the spreading of the peste des petits ruminants (PPR) disease for the past decade (from the year 2007 to 2017), assesses the resulting situation in the world, and has an emphasis on Russian advantages been a PPR host.

Materials and Methods: Outbreaks were confirmed and reported officially by the World Organization for Animal Health (enzyme-linked immunosorbent assay and polymerase chain reaction were used). Data contain the account number of infected, dead, and all susceptible animals in focus of infection in the period of 2007-2017. Once conventional statistical population was defined, a model was installed. Geo-information system QuickMAP was used to clear up the map disease, and through the ^@Risk program, we got our forecasting value of future situations (by Monte Carlo method).

Results: The spatial study of PPR’s occurrence and its spread was mapping according to the incidence of cases and outbreaks. Clusters demonstrated risk levels in the world in the period from 2007 to 2017 year. Based on the epizootological analysis, an assessment of PPR risk and the probability movement of infection in Russia from nearby disadvantaged countries had been carried out. A statistically significant impact of the socioeconomic system on the stationarity index was found equal to 0.63. The PPR risk of spreading could not be ignored. Nevertheless, conducting effective large-scale vaccine companies in a complex of antiepizootic activities against PPR could reduce the risk of spread of the disease up to 91.8%.

Conclusion: Despite all mentioned facts above, the PPR probability can only be reduced by coordinating work of border veterinary services, as in disadvantaged as in free from this disease country, that is, what makes an effective and complete eradication of the disease could be quite realistic.

Keywords

Forecast, Incidence, Outbreaks, Peste Des Petit Ruminants, Risk Factors.

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