Spatio-Temporal Analysis of the Spread of ASF in the Russian Federation in 2017-2019

Abstract

<jats:title>Abstract</jats:title><jats:p>Currently, African swine fever (ASF) is one of the biggest global economic challenges in Europe and Asia. Despite all the efforts done to understand the mechanism of spread, presence and maintenance of ASF in domestic pigs and wild boar, there are still many gaps in the knowledge on its epidemiology.</jats:p><jats:p>This study aims to describe spatial and temporal patterns of ASF spread in wild boar and domestic pigs in the country during the last three years. Methods of Spatio-temporal scanning statistics of Kulldorff (SatScan) and Mann-Kendell statistics (space-time cube) were used to identify potential clusters of outbreaks and the presence of hot spots (areas of active flare clusters), respectively. The results showed that ASF in the country has a local epidemic pattern of spread (11 explicit clusters in wild boar and 16 epizootic clusters were detected in the domestic pig population: 11 in the European part and 5 in the Asian part), and only six of them are overlapped suggesting that ASF epidemics in domestic pigs and wild boar are two separate processes. In the Nizhny Novgorod, Vladimir, Ivanovo, Novgorod, Pskov, Leningrad regions, the clusters identified are characterized as sporadic epidemics clusters, while in the Ulyanovsk region, Primorsky Territory, and the Jewish Autonomous Region the clusters are consistent. Considering the low biosecurity level of pig holdings in the far east and its close economic and cultural connections with China as well as other potential risk factors, it can be expected that the epidemic will be present in the region for a long time. The disease has spread in the country since 2007, and now it is reoccurring in some of the previously affected regions. Outbreaks in the domestic pig sector can be localized easily (no pattern detected), while the presence of the virus in wildlife (several consecutive hot spots detected) hampers its complete eradication. Although the disease has different patterns of spread over the country its driving forces remain the same (human-mediated spread and wild boar domestic-pigs mutual spillover). The results indicate that despite all efforts taken since 2007, the policy of eradication of the disease needs to be reviewed, especially measures in wildlife.</jats:p>

African Swine Fever in Wild Boar in Europe—A Review

“…Spatial analysis of data from the RF obtained between 2007 and 2013 revealed clusters of ASF in wild boar, domestic pigs and overlapping clusters [82]. Similar results were obtained for the time period 2017-2019 [87]. These studies indicate that the virus was able to persist in wild boar without constant reintroduction from domestic pigs in this region.…”

Risk factors for African swine fever spread in wild boar in the Russian Federation

“…Выявленные пространственно-временные закономерности распространения вспышек АЧС в субъектах РФ дают возможность предположить, что даже при наличии низкой плотности популяции кабана (менее 0,25 особи на 1000 га площади охотничьих угодий) сохраняется возможность передачи возбудителя от инфицированных объектов восприимчивым животным и распространения вируса в окружающей среде [41,42] Неоднократно в литературных источниках охота указывается как фактор риска распространения АЧС в связи с потенциальными миграциями кабанов в результате охотхозяйственной деятельности человека. Поэтому при обнаружении инфицированного вирусом АЧС кабана и установлении карантина на территории охотничьего угодья рекомендуют прекратить все возможные виды охоты в пределах зоны наблюдения, кроме мероприятий по регулированию численности кабана специально обученными людьми с соблюдением необходимых мер по недопущению передвижения животных за периметр данной зоны [43,44].…”

Investigation of Risk Factors Associated with the African Swine Fever Outbreaks in the Nizhny Novgorod Region of Russia, 2011–2022

“…In some cases, the deaths of wild boar from ASF were registered near farms [4,16]. Spatiotemporal analysis in the Russian Federation showed that ASF outbreaks in both domestic pigs and wild boars correlated to each other [17,18]. The spread of ASF in European countries demonstrated the significance of the wild boar population density factor, although the wild boar was not the original cause of the infection.…”