Genetic characteristics of spring viraemia of carp virus strains Kirov/08 and Orenburg/14.

The paper presents the genetic characteristics of two strains of spring viraemia of carp virus (SVCV), Kirov/08 and Orenburg/14, isolated in the Kirov and Orenburg oblasts of the Russian Federation, respectively. Nucleotide sequence analysis of a 516-bp fragment of the G genes of Kirov/08 and Orenburg/14 showed 9.5% divergence. Phylogenetic analysis demonstrated a close relationship of these strains to SVCV isolates recovered in Russia, Ukraine, and the Republic of Moldova.

Rabies surveillance in the Russian Federation.

Rabies is endemic to the Russian Federation. The disease incidence ranges between 2,000 and 4,000 cases annually. Between two and six cases in humans are also reported each year. Wild animals are the basic reservoir and vector of the virus, and the incidence of rabies in foxes and raccoon dogs amounts to 50% of the total number of disease cases. When outbreaks occur, the disease is also reported in domestic animals. To prevent the further spread of rabies, vaccination of domestic animals and oral immunisation of wildlife are practised. Unfortunately, vaccine coverage and disease prevention measures have not been sufficient to achieve a notable improvement in the rabies situation in the country.

La rage est présente à l'état endémique dans la Fédération de Russie. Son incidence varie de 2 000 à 4 000 cas par an. Deux à six cas de rage humaine sont également enregistrés chaque année. Les animaux sauvages constituent le principal réservoir et vecteur du virus, l'incidence de la rage chez le renard et le chien viverrin représentant 50 % du nombre total de cas. En cas de foyer, la maladie affecte également les animaux domestiques. La vaccination des animaux domestiques et l'immunisation orale de la faune sauvage sont les deux mesures appliquées pour empêcher la rage de se propager davantage. Malheureusement, la couverture vaccinale obtenue et les mesures de prévention appliquées n'ont pas suffi à améliorer significativement la situation de la rage.

La rabia es endémica en la Federación de Rusia, con una incidencia que va de los 2 000 a los 4 000 casos anuales. Cada año se notifican entre dos y seis casos en el ser humano. Los animales silvestres son el principal reservorio y vector del virus: la incidencia de la rabia en zorros y mapaches supone el 50% de la totalidad de los casos. Cuando estallan brotes también se registran casos en animales domésticos. Para impedir que la enfermedad se siga propagando se procede a la vacunación de los animales domésticos y a la inmunización oral de la fauna silvestre. Lamentablemente, la cobertura de vacunación y las medidas de prevención no han bastado para lograr una mejora sustancial de la situación de la rabia.

Spatiotemporal analysis of foot-and-mouth disease outbreaks in the Republic of Kazakhstan, 1955 - 2013.

Foot-and-mouth disease (FMD) poses a significant obstacle to international trade and economic development, and for that reason, FMD prevention, control and eradication are major goals guiding animal health policy in most countries. The purpose of this study was to conduct a retrospective spatiotemporal analysis of FMD outbreaks among livestock in the Republic of Kazakhstan (RK) from 1955 to 2013. During that time, several FMD control strategies were implemented in RK, which culminated with the World Organization for Animal Health (OIE) recognition of RK as a country that is FMD-free with partial vaccination (2015). Here, we describe and analyse the changes in spatial and temporal dynamics of FMD under different control strategies that were utilized as the country progressively moved towards eradication of the disease. A total number of 5,260 FMD outbreaks of serotype O and A (including the A22 lineage) were recorded in the cattle, pig and small ruminant populations of RK during that period. We found that outbreaks occurred in spatiotemporal clusters only prior to 1970, which is before ring vaccination around outbreaks was first employed. This finding suggests that ring vaccination substantially reduced local spread and prevented large FMD epidemics in the country. Disease incidence steadily decreased after the implementation of ring vaccination and culling of infected animals, with spatiotemporal clusters only occurring as a result of an introduction of an antigenically distinct variant of serotype A. From 1955 to 1984, FMD outbreaks demonstrated two seasonal peaks of incidence in the spring and fall. In contrast, only the peak in spring was observed between 1984 and 2013. Quantitative knowledge on how different policy and alternative control strategies contributed to RK achieving FMD-free status could improve prospects for continued control in RK and inform control strategies in other FMD-endemic regions.

Estimating the Basic Reproductive Number for African Swine Fever Using the Ukrainian Historical Epidemic of 1977.

In 1977, Ukraine experienced a local epidemic of African swine fever (ASF) in the Odessa region. A total of 20 settlements were affected during the course of the epidemic, including both large farms and backyard households. Thanks to timely interventions, the virus circulation was successfully eradicated within 6 months, leading to no additional outbreaks. Detailed report of the outbreak's investigation has been publically available from 2014. The report contains some quantitative data that allow studying the ASF-spread dynamics in the course of the epidemic. In our study, we used this historical epidemic to estimate the basic reproductive number of the ASF virus both within and between farms. The basic reproductive number (R0 ) represents the average number of secondary infections caused by one infectious unit during its infectious period in a susceptible population. Calculations were made under assumption of an exponential initial growth by fitting the approximating curve to the initial segments of the epidemic curves. The R0 both within farm and between farms was estimated at 7.46 (95% confidence interval: 5.68-9.21) and 1.65 (1.42-1.88), respectively. Corresponding daily transmission rates were estimated at 1.07 (0.81-1.32) and 0.09 (0.07-0.10). These estimations based on historical data are consistent with those using data generated by the recent epidemic currently affecting eastern Europe. Such results contribute to the published knowledge on the ASF transmission dynamics under natural conditions and could be used to model and predict the spread of ASF in affected and non-affected regions and to evaluate the effectiveness of different control measures.

Maximum entropy modeling risk of anthrax in the Republic of Kazakhstan.

The objective of this study was to zone the territory of the Republic of Kazakhstan (RK) into risk categories according to the probability of anthrax emergence in farm animals as stipulated by the re-activation of preserved natural foci. We used historical data on anthrax morbidity in farm animals during the period 1933 - 2014, collected by the veterinary service of the RK. The database covers the entire territory of the RK and contains 4058 anthrax outbreaks tied to 1798 unique locations. Considering the strongly pronounced natural focality of anthrax, we employed environmental niche modeling (Maxent) to reveal patterns in the outbreaks' linkages to specific combinations of environmental factors. The set of bioclimatic factors BIOCLIM, derived from remote sensing data, the altitude above sea level, the land cover type, the maximum green vegetation fraction (MGVF) and the soil type were examined as explanatory variables. The model demonstrated good predictive ability, while the MGVF, the bioclimatic variables reflecting precipitation level and humidity, and the soil type were found to contribute most significantly to the model. A continuous probability surface was obtained that reflects the suitability of the study area for the emergence of anthrax outbreaks. The surface was turned into a categorical risk map by averaging the probabilities within the administrative divisions at the 2nd level and putting them into four categories of risk, namely: low, medium, high and very high risk zones, where very high risk refers to more than 50% suitability to the disease re-emergence and low risk refers to less than 10% suitability. The map indicated increased risk of anthrax re-emergence in the districts along the northern, eastern and south-eastern borders of the country. It was recommended that the national veterinary service uses the risk map for the development of contra-epizootic measures aimed at the prevention of anthrax re-emergence in historically affected regions of the RK. The map can also be considered when developing large-scale construction projects in the areas comprising preserved soil foci of anthrax.

Spatio-temporal modeling of the African swine fever epidemic in the Russian Federation, 2007-2012.

In 2007 African swine fever (ASF) entered Georgia and in the same year the disease entered the Russian Federation. From 2007 to 2012 ASF spread throughout the southern region of the Russian Federation. At the same time several cases of ASF were detected in the central and northern regions of the Russian Federation, forming a northern cluster of outbreaks in 2011. This northern cluster is of concern because of its proximity to mainland Europe. The aim of this study was to use details of recorded ASF outbreaks and human and swine population details to estimate the spatial distribution of ASF risk in the southern region of the European part of the Russian Federation. Our model of ASF risk was comprised of two components. The first was an estimate of ASF suitability scores calculated using maximum entropy methods. The second was an estimate of ASF risk as a function of Euclidean distance from index cases. An exponential distribution fitted to a frequency histogram of the Euclidean distance between consecutive ASF cases had a mean value of 156 km, a distance greater than the surveillance zone radius of 100-150 km stated in the ASF control regulations for the Russian Federation. We show that the spatial and temporal risk of ASF expansion is related to the suitability of the area of potential expansion, which is in turn a function of socio-economic and geographic variables. We propose that the methodology presented in this paper provides a useful tool to optimize surveillance for ASF in affected areas.

African swine fever in the Russian Federation: spatio-temporal analysis and epidemiological overview.

African swine fever is viral disease of domestic and wild pigs which leads to almost total mortality and causes great economic losses due to absence of vaccine. Having been introduced into the Russian Federation in 2007 the disease has spread widely in the southern region of the country and since 2011 has demonstrated a tendency to form a secondary endemic zone in the central part of the country. In the present study spatio-temporal patterns of ASF diffusion in the populations of wild and domestic pigs are analyzed. The structure of the domestic swine population is conventionally divided into a sub-population at low biosecurity (77% of the total number of outbreaks in domestic pigs) and a population at high biosecurity (23%). The statistics of ASF cases registered in each of these sub-populations is presented. The possible causes of ASF diffusion across the country are discussed. The use of geo-information technologies (GIS) enabled confirmation of the conclusion that an epidemic center has shifted into the central part of Russia. The main conclusions of this study are that: (1) anthropogenic factors play the leading role in the spread of ASF across the territory of the RF; (2) small-scale private holdings (low biosecurity population) are more exposed to ASF virus introduction; (3) there is a high risk of diffusion of ASFV from the secondary endemic zone in the central part of the RF to neighboring regions.

Cartographical analysis of African swine fever outbreaks in the territory of the Russian Federation and computer modeling of the basic reproduction ratio.

African swine fever (ASF), have been introduced into the Russian Federation from Transcaucasia countries, has spread widely across the territory of the southern region of Russia since 2008. In this work we present an analysis of the spatial and temporal spread of the disease, determine risk factors by means of GIS tools and model the dynamics of the epidemic process both within infected premises (farms) and at the between-farm level to estimate the basic reproduction ratio R(0). The analysis allowed us to make a conclusion about the anthropogenic nature of the risk factors for disease spread. The major significant risk factors identified were: density of the road network, density of domestic swine population and density of water bodies in the study area. The basic reproduction ratio was estimated to range from 2 to 3 at the between-farm level and from 8 to 11 within the infected farms. These initial studies of the ASF epidemic provide information on which to based control and prevention programs.