lancet-header

Preprints with The Lancet is part of SSRN´s First Look, a place where journals identify content of interest prior to publication. Authors have opted in at submission to The Lancet family of journals to post their preprints on Preprints with The Lancet. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early stage research papers that have not been peer-reviewed. The findings should not be used for clinical or public health decision making and should not be presented to a lay audience without highlighting that they are preliminary and have not been peer-reviewed. For more information on this collaboration, see the comments published in The Lancet about the trial period, and our decision to make this a permanent offering, or visit The Lancet´s FAQ page, and for any feedback please contact preprints@lancet.com.

International Trades of Pigs and Pork Products Accelerate the Global Spread of African Swine Fever

57 Pages Posted: 14 Aug 2019

See all articles by Bo Xu

Bo Xu

Tsinghua University - Department of Earth System Science

Chutian Zhang

Northwest Agricultural and Forestry University

Heyuan Qi

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

Rongliang Hu

Academy of Military Sciences

Juncai Ma

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

George F. Gao

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

Peng Gong

Tsinghua University - Department of Earth System Science

Wenjun Liu

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

Lei Xu

Tsinghua University - Department of Earth System Science; Joint Center for Global Change Studies

Jing Li

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology; Chinese Academy of Sciences (CAS)

Bing Xu

Tsinghua University - Department of Earth System Science; Joint Center for Global Change Studies

More...

Abstract

Background: The global spread of African swine fever (ASF) has affected nearly half of the world pork market and caused great economic loss. Current studies have identified fairly complex transmission routes of this infectious disease. However, some evidences indicate that international trade of domestic pigs and their products may be another important factor facilitating the spatial spread of ASFV, but studies targeting the impact of international trade worldwide are limited.

Methods: To investigate the possible global spreading routes of ASF, the nearest neighbor approach (NNA) was applied. Phylogenetic analyses based on all the publicly available ASFV DNA sequences were further conducted to estimate the genetic homology of sequences isolated in different countries. To evaluate the impacts of environmental conditions and human activities on ASF epidemics and to identify high-risk regions, we used ecological niche model (ENM). To simulate the global diffusion of AFSV facilitated by the international trade of domestic pigs and products, we constructed Susceptible-Infectious (S-I) epidemiological metapopulation models.

Findings: We identified 24 genotypes and estimated the global spreading patterns of ASFV using NNA method. ASFV spread from Southern Africa to Eastern Europe and then most likely spread from Russia to China and Mongolia. According to the results of ENMs, the spreading cycle of ASFV could be divided into spreading via human transportation, such as trading of domestic pigs or pork, and spreading via natural processes, such as in wild boar populations. Furthermore, the established epidemiological metapopulation models showed that some countries, regardless of their geographic distance, shared similar changing patterns of yearly transmission rate over time, indicated that the international transportation and trades of live pigs and products may synchronize the ASF epidemics in countries with trade exchanges.

Interpretation: The international trades of pigs and products probably accelerated the global spread of ASFV among domestic pigs. In dealing with ongoing and future epidemics, an understanding of both the conditions favorable for ASFV and the mechanism of its transmission dynamics will help policy-makers to take effective prevention and control measures.

Funding Statement: This work was supported by Grants from the National Key R&D Program of China5 (No: 2018YFC0840402, 2016YFA0600104), Research Project of African Swine Fever of Chinese Academy of Sciences (No: KJZD-SW-L06-02), and donations from Delos Living LLC and the Cyrus Tang Foundation to Tsinghua University. Bo Xu was also partially supported by Scholarship of China Scholarship Council. W.L. is the principal investigator of the Innovative Research Group of the National Natural Science Foundation of China (Grant No. 81621091). J.L. is supported by Youth Innovation Promotion Association of CAS (2019091).

Declaration of Interests: All authors declare that they have no conflict of interest.

Ethics Approval Statement: Not required.

Keywords: African swine fever, ecological niche model, metapopulation epidemiological model, international trade, domestic pigs

Suggested Citation

Xu, Bo and Zhang, Chutian and Qi, Heyuan and Hu, Rongliang and Ma, Juncai and Gao, George F. and Gong, Peng and Liu, Wenjun and Xu, Lei and Li, Jing and Xu, Bing, International Trades of Pigs and Pork Products Accelerate the Global Spread of African Swine Fever (August 7, 2019). Available at SSRN: https://ssrn.com/abstract=3433899 or http://dx.doi.org/10.2139/ssrn.3433899

Bo Xu

Tsinghua University - Department of Earth System Science

China

Chutian Zhang

Northwest Agricultural and Forestry University

Yangling, Shaanxi 712100
China

Heyuan Qi

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

52 Sanlihe Rd.
Datun Road, Anwai
Beijing, Xicheng District 100864
China

Rongliang Hu

Academy of Military Sciences

China

Juncai Ma

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

52 Sanlihe Rd.
Datun Road, Anwai
Beijing, Xicheng District 100864
China

George F. Gao

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

52 Sanlihe Rd.
Datun Road, Anwai
Beijing, Xicheng District 100864
China

Peng Gong

Tsinghua University - Department of Earth System Science

China

Wenjun Liu

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology

52 Sanlihe Rd.
Datun Road, Anwai
Beijing, Xicheng District 100864
China

Lei Xu

Tsinghua University - Department of Earth System Science ( email )

China

Joint Center for Global Change Studies ( email )

China

Jing Li (Contact Author)

Chinese Academy of Sciences (CAS) - CAS Key Laboratory of Pathogenic Microbiology and Immunology ( email )

52 Sanlihe Rd.
Datun Road, Anwai
Beijing, Xicheng District 100864
China

Chinese Academy of Sciences (CAS) ( email )

Building 7, NO. 80 Zhongguancun Road
Beijing, Beijing 100190
China

Bing Xu

Tsinghua University - Department of Earth System Science ( email )

China

Joint Center for Global Change Studies ( email )

China