Risk Scoring of African Swine Fever Transmission in Selected Provinces of the Philippines

Overview

Journal J Vet Sci

Specialty Veterinary Medicine

Date 2025 Jan 3

PMID 39749378

Authors

John Michael G Bernardo

Aaron Paul R Serdena

Gladys Maria V Pangga

Saubel Ezrael A Salamat

Trisha Nicole Agulto

Cherry P Fernandez-Colorado

Affiliations

Soon will be listed here.

Abstract

Importance: African swine fever (ASF) is a contagious transboundary swine disease that poses a significant threat to the swine industry. As an archipelago, the Philippines has a geographic advantage in reducing ASF transmission risk. However, control efforts remain challenging due to the disease's complex epidemiology, lack of effective treatment, and vaccine availability. ASF transmission risk evaluation currently includes positive cases, population density, and pork production volume, but the potential role of contaminated pork commodities remains unexplored.

Objective: Using semiquantitative risk scoring, this study estimated the probability of ASF transmission in 23 selected provinces.

Methods: The factors influencing ASF spread were identified; 10 through a literature review and the positivity for ASF virus (ASFv) of meat samples from an ongoing surveillance study. Secondary data from each sampled province were collected, and the provinces were scored across these factors and classified into one of three risk categories.

Results: Six out of 23 provinces were categorized as high-risk due to the high number of ASFv-positive meat samples, backyard pigs, and ASF occurrences. Conversely, four provinces were classified as low-risk due to consistently low scores across all indicators. The difference in the meat contamination level between low- and high-risk provinces emphasizes the importance of including this factor in the ASF spread assessment.

Conclusions And Relevance: Risk estimation of ASF transmission must consider meat sample contamination. Active surveillance at local borders can monitor contamination and prevent ASFv sources from entering areas. This approach allows the government to allocate resources and prioritize higher-risk areas.

References

Nurmoja I, Motus K, Kristian M, Niine T, Schulz K, Depner K . Epidemiological analysis of the 2015-2017 African swine fever outbreaks in Estonia. Prev Vet Med. 2018; 181:104556. DOI: 10.1016/j.prevetmed.2018.10.001. View

Kim H, Lee M, Lee S, Kim D, Seo S, Kang H . African Swine Fever Virus in Pork Brought into South Korea by Travelers from China, August 2018. Emerg Infect Dis. 2019; 25(6):1231-1233. PMC: 6537713. DOI: 10.3201/eid2506.181684. View

Kim Y, Park B, Kang H . Control measures to African swine fever outbreak: active response in South Korea, preparation for the future, and cooperation. J Vet Sci. 2021; 22(1):e13. PMC: 7850787. DOI: 10.4142/jvs.2021.22.e13. View

Fernandez-Colorado C, Kim W, Flores R, Min W . African Swine Fever in the Philippines: A Review on Surveillance, Prevention, and Control Strategies. Animals (Basel). 2024; 14(12). PMC: 11200829. DOI: 10.3390/ani14121816. View

Pavone S, Iscaro C, Dettori A, Feliziani F . African Swine Fever: The State of the Art in Italy. Animals (Basel). 2023; 13(19). PMC: 10571570. DOI: 10.3390/ani13192998. View

Glazunova A, Korennoy F, Sevskikh T, Lunina D, Zakharova O, Blokhin A . Risk Factors of African Swine Fever in Domestic Pigs of the Samara Region, Russian Federation. Front Vet Sci. 2021; 8:723375. PMC: 8421595. DOI: 10.3389/fvets.2021.723375. View

Chenais E, Depner K, Guberti V, Dietze K, Viltrop A, Stahl K . Epidemiological considerations on African swine fever in Europe 2014-2018. Porcine Health Manag. 2019; 5:6. PMC: 6325717. DOI: 10.1186/s40813-018-0109-2. View

Sanchez-Vizcaino J, Mur L, Gomez-Villamandos J, Carrasco L . An update on the epidemiology and pathology of African swine fever. J Comp Pathol. 2014; 152(1):9-21. DOI: 10.1016/j.jcpa.2014.09.003. View

Costard S, Wieland B, de Glanville W, Jori F, Rowlands R, Vosloo W . African swine fever: how can global spread be prevented?. Philos Trans R Soc Lond B Biol Sci. 2009; 364(1530):2683-96. PMC: 2865084. DOI: 10.1098/rstb.2009.0098. View

10.

Nuanualsuwan S, Songkasupa T, Boonpornprasert P, Suwankitwat N, Lohlamoh W, Nuengjamnong C . Persistence of African swine fever virus on porous and non-porous fomites at environmental temperatures. Porcine Health Manag. 2022; 8(1):34. PMC: 9331492. DOI: 10.1186/s40813-022-00277-8. View

11.

Aguero M, Fernandez J, Romero L, Sanchez Mascaraque C, Arias M, Sanchez-Vizcaino J . Highly sensitive PCR assay for routine diagnosis of African swine fever virus in clinical samples. J Clin Microbiol. 2003; 41(9):4431-4. PMC: 193827. DOI: 10.1128/JCM.41.9.4431-4434.2003. View

12.

Zhao D, Sun E, Huang L, Ding L, Zhu Y, Zhang J . Highly lethal genotype I and II recombinant African swine fever viruses detected in pigs. Nat Commun. 2023; 14(1):3096. PMC: 10226439. DOI: 10.1038/s41467-023-38868-w. View

13.

Horigan V, Simons R, Kavanagh K, Kelly L . A review of qualitative risk assessment in animal health: Suggestions for best practice. Front Vet Sci. 2023; 10:1102131. PMC: 9941190. DOI: 10.3389/fvets.2023.1102131. View

14.

Podgorski T, Borowik T, Lyjak M, Wozniakowski G . Spatial epidemiology of African swine fever: Host, landscape and anthropogenic drivers of disease occurrence in wild boar. Prev Vet Med. 2019; 177:104691. DOI: 10.1016/j.prevetmed.2019.104691. View

15.

Huang Z, van Langevelde F, Honer K, Naguib M, de Boer W . Regional level risk factors associated with the occurrence of African swine fever in West and East Africa. Parasit Vectors. 2017; 10(1):16. PMC: 5219763. DOI: 10.1186/s13071-016-1953-z. View

16.

Hsu C, Montenegro M, Perez A . Space-Time Dynamics of African Swine Fever Spread in the Philippines. Microorganisms. 2023; 11(6). PMC: 10301302. DOI: 10.3390/microorganisms11061492. View

17.

Bellini S, Casadei G, De Lorenzi G, Tamba M . A Review of Risk Factors of African Swine Fever Incursion in Pig Farming within the European Union Scenario. Pathogens. 2021; 10(1). PMC: 7835761. DOI: 10.3390/pathogens10010084. View

18.

Nielsen S, Alvarez J, Bicout D, Calistri P, Depner K, Drewe J . Risk assessment of African swine fever in the south-eastern countries of Europe. EFSA J. 2020; 17(11):e05861. PMC: 7008867. DOI: 10.2903/j.efsa.2019.5861. View

19.

Cheng J, Ward M . Risk factors for the spread of African Swine Fever in China: A systematic review of Chinese-language literature. Transbound Emerg Dis. 2022; 69(5):e1289-e1298. PMC: 9790558. DOI: 10.1111/tbed.14573. View

20.

Hsu C, Schambow R, Montenegro M, Miclat-Sonaco R, Perez A . Factors Affecting the Spread, Diagnosis, and Control of African Swine Fever in the Philippines. Pathogens. 2023; 12(8). PMC: 10459637. DOI: 10.3390/pathogens12081068. View