scholarly journals Modelling the deathbed of ASF-infected wild boars in South Korea using 2019-2020 national surveillance data

2021 ◽  
Author(s):  
Jun-Sik Lim ◽  
Timothée Vergne ◽  
Son-Il Pak ◽  
Eutteum Kim

In September 2019, African swine fever (ASF) was reported in South Korea for the first time. Since then, more than 651 ASF cases in wild boars and 14 farm outbreaks have been notified in the country. The purpose of this study was to characterize the spatial distribution of ASF-positive wild boar carcasses to identify the risk factors associated with the presence of ASF and number of ASF-positive wild boar carcasses in the affected areas. To achieve this objective, we divided the study into two periods (October 2, 2019, to January 19, 2020, and January 19 to April 28, 2020) and aggregated the number of reported ASF-positive carcasses into a regular grid of hexagons. To account for imperfect detection, we adjusted spatial zero-inflated Poisson regression models to the number of ASF-positive wild boar carcasses per hexagons. During the first study period, only proximity to North Korea was identified as a risk factor for the presence of African swine fever virus (ASFV). In addition, there were more reports in the affected hexagons with a high habitat suitability for wild boar, low heat load index (HLI), and high human density. During the second study period, proximity to an ASF-positive carcass reported during the first period was the only significant risk factor for the presence of ASF-positive carcasses. Additionally, high HLI and low elevation were associated with an increased number of ASF-positive carcasses reported in the affected hexagons. Although the proportion of ASF-affected hexagons increased from 0.06 (95% credible interval [CrI]: 0.05-0.07) to 0.09 (95% CrI: 0.08-0.10), the probability of reporting ASF-affected hexagons increased substantially from 0.49 (95% CrI: 0.41-0.57) to 0.73 (95% CrI: 0.66-0.81) between the two study periods. These results can be used to further advance risk-based surveillance.

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1208
Author(s):  
Jun-Sik Lim ◽  
Timothée Vergne ◽  
Son-Il Pak ◽  
Eutteum Kim

In September 2019, African swine fever (ASF) was reported in South Korea for the first time. Since then, more than 651 ASF cases in wild boars and 14 farm outbreaks have been notified in the country. Despite the efforts to eradicate ASF among wild boar populations, the number of reported ASF-positive wild boar carcasses have increased recently. The purpose of this study was to characterize the spatial distribution of ASF-positive wild boar carcasses to identify the risk factors associated with the presence and number of ASF-positive wild boar carcasses in the affected areas. Because surveillance efforts have substantially increased in early 2020, we divided the study into two periods (2 October 2019 to 19 January 2020, and 19 January to 28 April 2020) based on the number of reported cases and aggregated the number of reported ASF-positive carcasses into a regular grid of hexagons of 3-km diameter. To account for imperfect detection of positive carcasses, we adjusted spatial zero-inflated Poisson regression models to the number of ASF-positive wild boar carcasses per hexagon. During the first study period, proximity to North Korea was identified as the major risk factor for the presence of African swine fever virus. In addition, there were more positive carcasses reported in affected hexagons with high habitat suitability for wild boars, low heat load index (HLI), and high human density. During the second study period, proximity to an ASF-positive carcass reported during the first period was the only significant risk factor for the presence of ASF-positive carcasses. Additionally, low HLI and elevation were associated with an increased number of ASF-positive carcasses reported in the affected hexagons. Although the proportion of ASF-affected hexagons increased from 0.06 (95% credible interval (CrI): 0.05–0.07) to 0.09 (95% CrI: 0.08–0.10), the probability of reporting at least one positive carcass in ASF-affected hexagons increased from 0.49 (95% CrI: 0.41–0.57) to 0.73 (95% CrI: 0.66–0.81) between the two study periods. These results can be used to further advance risk-based surveillance strategies in the Republic of Korea.


Pathogens ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 688 ◽  
Author(s):  
Antonio Rodríguez-Bertos ◽  
Estefanía Cadenas-Fernández ◽  
Agustín Rebollada-Merino ◽  
Néstor Porras-González ◽  
Francisco J. Mayoral-Alegre ◽  
...  

African swine fever (ASF) is a notifiable disease that in recent years has spread remarkably in Europe and Asia. Eurasian wild boar (Sus scrofa) plays a key role in the maintenance and spread of the pathogen. Here we examined gross pathology of infection in wild boar with a highly virulent, hemadsorbing genotype II ASF virus (ASFV) strain. To this end, six wild boars were intramuscularly inoculated with the 10 HAD50 Arm07 ASFV strain, and 11 wild boars were allowed to come into direct contact with the inoculated animals. No animals survived the infection. Clinical course, gross pathological findings and viral genome quantification by PCR in tissues did not differ between intramuscularly inoculated or contact-infected animals. Postmortem analysis showed enlargement of liver and spleen; serosanguinous effusion in body cavities; and multiple hemorrhages in lungs, endocardium, brain, kidneys, urinary bladder, pancreas, and alimentary system. These results provide detailed insights into the gross pathology of wild boar infected with a highly virulent genotype II ASFV strain. From a didactic point of view, this detailed clinical course and macroscopic description may be essential for early postmortem detection of outbreaks in wild boar in the field and contribute to disease surveillance and prevention efforts.


2020 ◽  
Vol 9 (1) ◽  
pp. 628-630 ◽  
Author(s):  
Seon-Hee Kim ◽  
Jisoo Kim ◽  
Kidong Son ◽  
Yongjun Choi ◽  
Hye-Sung Jeong ◽  
...  

Agriculture ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 45
Author(s):  
Maciej Frant ◽  
Anna Gal ◽  
Łukasz Bocian ◽  
Anna Ziętek-Barszcz ◽  
Krzysztof Niemczuk ◽  
...  

African swine fever (ASF) was introduced to Poland in 2014. Despite the implementation of preventive actions focused on the reduction of wild boar populations and the introduction of biosecurity rules in domestic pig farms, the disease has been continuously spreading to new areas. The aim of this paper was to analyze the dynamics of ASFV spread in wild boar populations in Poland and to summarize the 2019 epidemiological situation. Using a logistic regression model, it has been shown that there is a significant correlation between the month, ASF affected area and ASF prevalence among wild boars. According to EU definitions, Part II and Part III zones had a total of 3065 (65.2%) ASF-positive death wild boars. In addition, there were 36 post-accident (road-killed) wild boars (2.6%) and 612 hunted animals (1.5%) in this area. These results showed the importance of passive surveillance and its advantages overactive surveillance in ASF control and prevention. The data indicated a greater chance of a positive result in the winter months (January, February, March) than in reference September, where the ASF prevalence was the lowest. This observation confirms the preliminary theory about the seasonality of the disease in wild boar populations and its connection with winter.


2020 ◽  
Vol 65 (No. 4) ◽  
pp. 143-158 ◽  
Author(s):  
MP Frant ◽  
M Lyjak ◽  
L Bocian ◽  
A Barszcz ◽  
K Niemczuk ◽  
...  

African swine fever (ASF) was first described in 1921 in Kenya. The latest epidemic of ASF started in 2007 in Georgia. The virus was introduced to Poland in 2014. Since the beginning of the epidemics, the National Veterinary Research Institute in Pulawy (NVRI) has been testing wild boar samples from restricted areas and other parts of Poland to conduct passive and active surveillance for ASFV in these groups of animals. The aim of this study was to summarise the last two years of the ASF epidemiological status in Poland and the attempt to find disease patterns in the wild boar population. The period between 2017 and 2018 brought a massive number of new ASF cases in Poland. The number of ASF-positive wild boars jumped from 91 in 2016 to 1 140 in 2017 (approximately a 12 × increase), and 2018 was even worse, with the disease affecting 4 083 animals (2 435 cases; one case could even be 10 animals or more if they are found in one place next to each other). The percentage of positive wild boars found dead (passive surveillance) in the restricted area increased in 2018 to 73.1% from 70.8% in 2017. The chance of obtaining positive results in this group was six times higher in December and 4.5 times higher in January than in August and September. The percentage of positive wild boars detected through active surveillance reached 1.5% in 2018. The data suggested that, not only in Poland, but also in other ASF-affected countries, during the epizootic stage of the disease spread the most important measure is an effective passive surveillance of dead wild boars especially, in the winter season rather than in the summer.


2021 ◽  
Vol 77 (02) ◽  
pp. 6501-2021
Author(s):  
KAZIMIERZ TARASIUK ◽  
ZYGMUNT GIŻEJEWSKI

Recent years (since 2013) have witnessed an increasing interest in wild boars in Europe because this animal species has become the most important reservoir of the African swine fever virus (ASFV). In all countries affected by ASF since 2013, the virus originated in wild boar populations, and the disease was directly or indirectly transmitted from wild boars to domestic pigs. In Poland, the first known case of ASF was detected in February 2014, and nearly 10 300 cases were reported by the end of April 2020. A correlation was found between the density of wild boar populations and the number of ASF cases. The global population of wild boars has increased considerably, and their natural range has expanded, particularly northward and westward. The mean annual growth rate in the wild boar population in Europe is around 100%. Milder winters and agricultural transformations that involve growing a single crop (in particular, maize) over large areas are the key factors contributing to the increase in the number of wild boars. In the opinion of most experts, recreational hunting is not sufficient to control the expansion of wild boar populations in Europe. Undoubtedly, wild boar populations will continue to be the main reservoir of the ASFV for many years to come, and wild boars will remain the major risk factor for ASF spread in commercial pig herds. Therefore, a new long-term approach to wild boar population management is needed


2021 ◽  
Vol 22 ◽  
Author(s):  
Kyung-Lak Lee ◽  
Yongjun Choi ◽  
Jongchan Yoo ◽  
Jusun Hwang ◽  
Hyun-Gi Jeong ◽  
...  

Crisis ◽  
2014 ◽  
Vol 35 (5) ◽  
pp. 330-337 ◽  
Author(s):  
Cun-Xian Jia ◽  
Lin-Lin Wang ◽  
Ai-Qiang Xu ◽  
Ai-Ying Dai ◽  
Ping Qin

Background: Physical illness is linked with an increased risk of suicide; however, evidence from China is limited. Aims: To assess the influence of physical illness on risk of suicide among rural residents of China, and to examine the differences in the characteristics of people completing suicide with physical illness from those without physical illness. Method: In all, 200 suicide cases and 200 control subjects, 1:1 pair-matched on sex and age, were included from 25 townships of three randomly selected counties in Shandong Province, China. One informant for each suicide or control subject was interviewed to collect data on the physical health condition and psychological and sociodemographic status. Results: The prevalence of physical illness in suicide cases (63.0%) was significantly higher than that in paired controls (41.0%; χ2 = 19.39, p < .001). Compared with suicide cases without physical illness, people who were physically ill and completed suicide were generally older, less educated, had lower family income, and reported a mental disorder less often. Physical illness denoted a significant risk factor for suicide with an associated odds ratio of 3.23 (95% CI: 1.85–5.62) after adjusted for important covariates. The elevated risk of suicide increased progressively with the number of comorbid illnesses. Cancer, stroke, and a group of illnesses comprising dementia, hemiplegia, and encephalatrophy had a particularly strong effect among the commonly reported diagnoses in this study population. Conclusion: Physical illness is an important risk factor for suicide in rural residents of China. Efforts for suicide prevention are needed and should be integrated with national strategies of health care in rural China.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ting-Chun Huang ◽  
Po-Tseng Lee ◽  
Mu-Shiang Huang ◽  
Pei-Fang Su ◽  
Ping-Yen Liu

AbstractPremature atrial complexes (PACs) have been suggested to increase the risk of adverse events. The distribution of PAC burden and its dose–response effects on all-cause mortality and cardiovascular death had not been elucidated clearly. We analyzed 15,893 patients in a medical referral center from July 1st, 2011, to December 31st, 2018. Multivariate regression driven by ln PAC (beats per 24 h plus 1) or quartiles of PAC burden were examined. Older group had higher PAC burden than younger group (p for trend < 0.001), and both genders shared similar PACs distribution. In Cox model, ln PAC remained an independent risk factor for all-cause mortality (hazard ratio (HR) = 1.09 per ln PAC increase, 95% CI = 1.06‒1.12, p < 0.001). PACs were a significant risk factor in cause-specific model (HR = 1.13, 95% CI = 1.05‒1.22, p = 0.001) or sub-distribution model (HR = 1.12, 95% CI = 1.04‒1.21, p = 0.004). In ordinal PAC model, 4th quartile group had significantly higher risk of all-cause mortality than those in 1st quartile group (HR = 1.47, 95% CI = 1.13‒1.94, p = 0.005), but no difference in cardiovascular death were found in competing risk analysis. In subgroup analysis, the risk of high PAC burden was consistently higher than in low-burden group across pre-specified subgroups. In conclusion, PAC burden has a dose response effect on all-cause mortality and cardiovascular death.


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