Successful Hosting of the Pest Control, Disinfection, and African Swine Fever Prevention Forum in Hefei, Anhui

(Zhou Panyi, China Animal Health Magazine) On April 13, the Forum on Insecticidal Disinfection andAfrican Swine Fever Prevention and Control was successfully held, sponsored bythe Chinese Veterinary Medical Association and hosted byAnhui Animal Disease Prevention and Control Center and Guangdong WensDahuanong Biotechnology Co., Ltd.

Xin Shengpeng, Secretary-General of theChina Veterinary Association, Liu Xiuli, Deputy Secretary-General of the ChinaVeterinary Association, Chen Hailin, Director of the Veterinary Department ofthe Anhui Provincial Department of Agriculture and Rural Affairs, ZhuLiangqiang, Director of the Anhui Provincial Animal Disease Prevention andControl Center, Ban Fuguo, Director of the Henan Provincial Animal DiseasePrevention and Control Center, Dong Yongyi, Director of the Jiangsu ProvincialAnimal Disease Prevention and Control Center, Professor Chen Ruiai from SouthChina Agricultural University and President of the DHN Division of Wens FoodGroup Co., Ltd., Professor Fang Binghu, Vice President of the DHN Division ofWens Food Group Co., Ltd., Professor Wang Jiaxin from Hebei AgriculturalUniversity, Associate Professor Weng Yabiao from South China AgriculturalUniversity, Ding Weimin, Technical Director of Anhui Antai Agricultural Group,Shi Zengbin, National Technical Service Director of the DHN Division of WensFood Group Co., Ltd., Zhan Songhe, Deputy Director of the Anhui ProvincialAnimal Disease Prevention and Control Center, and Researcher Cai Gengyuan,Deputy Director of the National Engineering Technology Research Center for PigBreeding, and more than two hundred representatives from veterinary departmentsand breeding enterprises across the country attended this meeting.

GroupPhoto of the Meeting

As of now, only Hainan, Hong Kong, Macao,and Taiwan have not reported any cases of African Swine Fever (ASF) in China.Currently, in Asia, China, Vietnam, Mongolia, and Cambodia have reportedoutbreaks of African Swine Fever, indicating that the disease is continuing tospread globally! Understanding the clinicalimmune mechanisms and control measures of the African Swine Fever Virus (ASFV)is an urgent need for pig farms under the current circumstances. In the absenceof a vaccine, improving the biosecurity level of breeding farms has become atop priority. Proper disinfection and vector control are crucial measures inthe prevention and control of African Swine Fever.

This conference combined theory withpractical experience, with several experts discussing the characteristics ofthe African Swine Fever Virus, the distribution and habits of arthropod vectorsthat transmit African Swine Fever, and enhancing the understanding of the basicknowledge of African Swine Fever control. The conference summarized thepractical experience of African Swine Fever control from both domestic andinternational sources, shared the construction of biosecurity systems in pigfarms, details of disinfectant use and disinfection details in pig farms, andexperiences in pig farm resumption. Manyparticipants expressed that the conference was "very practical, verybeneficial, took many photos of expert presentation slides, and will re-observethem, which greatly improves their own level of prevention and controltechnology."

Summarizing domestic and internationalexperience in the prevention and control of African Swine Fever, and learningfrom each other's strengths and weaknesses.

Secretary-Generalof the China Veterinary Association, Xin Shengpeng

Secretary-Generalof the China Veterinary Association, Xin Shengpeng, introduced the currentepidemic situation. China's pig farming accounts for more than 50% of theglobal total. Since the introduction of African Swine Fever (ASF) into Chinaeight months ago, there have been 122 outbreaks in 30 provinces. Currently, theepidemic is sporadically distributed and generally controllable.

The complexity of the structure, multiplegenotypes, strong resistance to physicochemical effects, long survival timeunder various environmental conditions, multiple transmission routes, and thedifficulty in on-site diagnosis of ASF have made the prevention and control ofAfrican Swine Fever challenging.

At present, there are various speculationsabout how African Swine Fever was introduced into China, such as "theRussian border theory," "the Poland and Georgia theory,""the imported frozen meat theory," "the tourist carryingtheory," "the international swill theory," "theChina-Europe train theory," "the Middle East crossing theory,"and "the Sino-American trade friction theory." Both international anddomestic parties have conducted multiple investigations and discussions, butthere is no conclusion yet.

Xin Shengpeng compared the pig inventory,per capita GDP, veterinary management systems, and measures taken by China,Brazil, Russia, and Haiti, and analyzed the impact factors on epidemic controland control. He pointed out that there is not much correlation with the numberof breeding and the economic strength of the country; the vertical management system of veterinary medicine isa commonality of countries that have eradicated African Swine Fever, andcountries that have eradicated African Swine Fever have elevated the preventionand control of African Swine Fever to the national will. Xin Shengpengemphasized that the participation of stakeholders in the formulation ofprevention and control plans is crucial.

Xin Shengpengcarefully explained the emergency disposal procedures for African Swine Feverand shared his insights from practice to cognition and back to practice. His understanding and summary of highly contagious diseases,transmission methods, risk factors, the social role of transmission media,prominent issues in breeding farms, and problems in grassroots epidemicprevention teams are vivid and thought-provoking. Among them, he metaphoricallydescribed the social roles of the transmission media of the African Swine Feverepidemic: slaughterhouses are amplifiers, pig transport vehicles are seeders,mobile personnel are couriers, and cold storage is a time bomb, which isimpressive. He provided 10 key measures fordoing a good job in the prevention and control of African Swine Fever,emphasizing that the key to the transformation and upgrading of the breedingindustry is not the size of the breeding farm, but the upgrade of diseaseprevention and control.

ProfessorChen Ruiai, South China Agricultural University and President of DHN Division,Wens Food Group Co., Ltd.

Professor ChenRuiai from South China Agricultural University and President of the DHNDivision of Wens Food Group Co., Ltd., shared insights on the construction of abiosecurity system for pig farms. She explained thesensitivity and survival characteristics of the African Swine Fever virus and introduced key actions taken by Spain after the outbreakof African Swine Fever:

Understanding thesource of infection and susceptible animals is the premise for constructing abiosecurity system. She shared eight key measures:

1.Pig farms musthave the hardware conditions for biosecurity control. Theyshould have designated areas for showering and disinfecting supplies; isolationquarters for new stock; a clear division between clean and contaminated areas;and physical barriers such as walls or fences to isolate the farm from theoutside world, especially around production areas.

2.Strictlyimplement testing and isolation for new stock. Farmswith the capacity can adhere to self-breeding and self-raising; new stock mustbe tested before introduction; confirmed negative, then subjected to off-siteisolation and monitoring before being introduced.

3.Strictly controlthe movement of personnel in the pig farm. Prohibitunrelated external personnel from visiting the farm; farm employees shouldminimize going out, and if they return from outside, they must strictlyimplement isolation and disinfection measures.

4.Strictly controlthe movement of materials in the pig farm. Prohibit contact with andpurchase of pork, beef, mutton, and their processed products from outside thefarm; newly purchased vaccines or drugs must be disinfected on the surface;newly purchased feed must be quarantined and tested, confirmed negative beforeuse; all equipment entering the farm must be disinfected and quarantined.

5.Strictly managethe transportation vehicles for pigs. Strictlycontrol all vehicles related to the farm, dedicated vehicles only, and prohibitvehicles that have not been cleaned and disinfected from approaching the farm;establish a vehicle cleaning and disinfection system, and farms with conditionscan establish a disinfection center; vehicles must undergo two rounds ofdisinfection.

6.Strictly enforceepidemic prevention and disinfection. Cover all keypoints of epidemic prevention and disinfection in the farm, check for omissionsand fill gaps, leaving no dead corners; establish a "two-pointthree-stage" pig exit platform, and thoroughly disinfect the platform andvehicles after each pig exit; stock up on sufficient disinfectants and otheremergency supplies, and appropriately increase the frequency of routinedisinfection.

7.Improve thelevel of breeding management. Prohibit feedingswill or kitchen waste; prohibit the use of contaminated pig feed preparations;strengthen the immunization and prevention of diseases such as porcinereproductive and respiratory syndrome (PRRS) and classical swine fever, improvedisease monitoring, and enhance the health level of the pig herd; farmpersonnel avoid moving between pens and do not use needles interchangeably;achieve all-in, all-out management.

8.Strengthen pestcontrol around the pig farm. Regularly disinfectthe farm and surrounding environment; establish a buffer isolation zone,prohibit contact between wild boars and the farm; regularly monitor whether thewater source is contaminated; eliminate soft ticks, flies, mosquitoes, rats,and prevent birds.

In addition, she also detailed material management and warehouse management.

Director Chen Hailin of the VeterinaryDepartment of the Anhui Provincial Department of Agriculture and Rural Affairs Director Chen Hailin ofthe Veterinary Department of the Anhui Provincial Department of Agriculture andRural Affairs, Director Ban Fuguo of the Henan Provincial Animal DiseasePrevention and Control Center, and Director Dong Yongyi of the Jiangsu ProvincialAnimal Disease Prevention and Control Center, respectively, introduced theexperiences of Anhui, Henan, and Jiangsu in the prevention and control ofAfrican Swine Fever.

After the outbreak of the epidemic, allprovinces quickly took epidemic control measures. The leadership paid highattention, implemented measures effectively, strengthened emergency management,strictly controlled the epidemic source, cut off the transmission routes, andprotected susceptible animals, thus stabilizing pig production.

Director Chen Hailin mentioned that pig farming enterprises in Anhui Province spontaneouslyorganized joint prevention and control against illegal transfers from otherprovinces, which played a positive role in the prevention and control of theepidemic within the province. The Veterinary Department has solicited andpromoted the practical methods of enterprises that have implemented epidemicprevention and control measures in the province, providing technical guidancefor other pig farms.

DirectorBan Fuguo of the Henan Provincial Animal Disease Prevention and Control Center

Director Ban Fuguo of the Henan ProvincialAnimal Disease Prevention and Control Center introduced the key measures forthe prevention and control of African Swine Fever implemented in HenanProvince, including "seven clearexplanations," "six strict prohibitions and six musts,""strict control of the irrelevant," and "seven preventions andfive controls."

DirectorDong Yongyi of the Jiangsu Provincial Animal Disease Prevention and ControlCenter

Director Dong Yongyi analyzed the cases of epidemics in Jiangsu Province andsummarized and reflected on them:

1.Advocatingmoderate scale is timely. The larger the scale, themore potential loopholes there may be; the higher the quality and managementrequirements for people in breeding farms; one should not blindly pursue largescale, with a maximum of 20,000 heads in stock.

2.Joint preventionand control is very important. It is necessary toprevent and control both domestically and internationally, to coordinatebetween departments, to address the disposal of kitchen waste (construction),to crack down on illegal online transactions (public security), to carry andsmuggle in passenger transport (transportation), and to eliminate panic(propaganda).

3.Controllingpeople and guarding the door is the most critical. Peopleare the most active factor. For breeding farms, the entry and exit and movementof personnel are the greatest risks, and it is necessary to strictly controlthe entrance and focus on controlling personnel, vehicles, and items.

4.Regionalprevention and control should avoid the shortcomings of production and salesareas. Production areas should improve slaughteringcapacity, and sales areas should moderately subsidize production areas.

5.Changingconsumption habits is a long-term task. Thetransition from consuming hot fresh meat to cold fresh meat, and fromtransporting live pigs to transporting pork, reducing long-distancetransportation of live pigs, etc., needs to be adapted to.

6.The core is torefine and implement measures. There are thousandsof measures, but implementation is the first. Feeding with swill is forbidden,and testing in the slaughtering process must be implemented in place.

Understanding the basic knowledge ofASFV and disinfectants, and doing a good job in the three-dimensionalprevention and control of African Swine Fever.

ProfessorWang Jiaxin of Hebei Agricultural University

Professor WangJiaxin from Hebei Agricultural University explained the biologicalcharacteristics of the African Swine Fever virus (ASFV) and the immunemechanisms of African Swine Fever. He noted thatthe tonsils are the gateway for ASFV invasion, and ASFV may spread throughoutthe body with lymphatic fluid and blood. The tonsil lymphatic vessels should bethe battlefield for vaccine efficacy, and he suggested that special attentionshould be paid to this area.

Why do sows have ahigher incidence and mortality rate of African Swine Fever? This issue has sparked heated discussions online. Professor WangJiaxin explained the genomic transcriptional and non-transcriptional pathwaysby which estrogen causes damage to endothelial cells. He believes that estrogen promotes the formation ofneutrophil extracellular traps (NETs) in sows, and NETs can cause thrombosisand endothelial cell damage in blood vessels, thereby exacerbating thecondition of African Swine Fever.

He gavesuggestions for African Swine Fever control strategies:

1.Based on the existing understanding,strictly follow statistical requirements to carry out clinical epidemiologicalresearch, especially immunological epidemiological research, to obtain clinicalevidence for scientific decision-making.

2.Conduct systematic vaccine research andestablish multi-level high-throughput technical standards.

3.Conduct structural biology research tofind disinfectant targets that act on the viral envelope, viral capsid, andnucleic acids.

AssociateProfessor Weng Yabiao of South China Agricultural University

AssociateProfessor Weng Yabiao from South China Agricultural University introduced themodes of transmission and infection of African Swine Fever. He believes thatthe role of vector-borne transmission in future African Swine Fever epidemicsshould not be overlooked. The soft tick is thebiological vector of African Swine Fever. In daily life, hard ticks arecommonly seen on cattle and sheep, and the habits of soft ticks are verydifferent: they usually live in burrows, hide in holes during the day, suckblood at night, and the blood-sucking time is short, which can be completed in5 minutes to half an hour; they have strong hunger resistance and can survivefor 5-10 years. Their special habits bring greater hidden dangers. Althoughticks are not currently the source of African Swine Fever infection in domesticpigs, with the expansion of pollution, apig-tick-pig infection chain may be formed. Once African Swine Fever infectsticks, it is particularly difficult to eliminate, and can be passed on throughmating, from generation to generation. If one tick is infected, its mate andoffspring will all carry it.

Experts such as Liu Jian have analyzed theadaptability of soft ticks in China and showed that some areas in China havehigh adaptability. Weng Yabiao learned thatsomeone has already found the traces of soft ticks in Guangdong, and he remindspig farms to be vigilant and suggests strengthening pest control in theenvironment.

In addition to ticks, other pests need tobe controlled because many common pests can cause the spread of the epidemic,such as flies. With the rise in temperature, flies and mosquitoes become moreactive, and pig farms with swarms of flies flying around will face a very highrisk of the epidemic.

Teacher WengYabiao proposed a three-dimensional prevention and control measure for pigfarms: physical means can include installingmosquito nets and adding fly-killing lamps in the pigsty; various chemicaldrugs can control flies, adult fly insecticides include contact insecticides:Shiman Jing (phoxim), etc., attractant insecticides: Yingzhang Ke (methylpyridyl phosphorothioate), and larvicidal insecticides include Chongying Jing(cyromazine), etc.

Fly and Mosquito Adult Spray KillingPlan

Usage location:pigsty and surrounding environment

1.Chongwu Jing, diluted 1:200 without deadcorners (i.e., 1 bottle diluted with 50 kg of water), sprayed 2-3 times a week,used continuously for a month, then switch to other insecticides;

2.Shiman Jing: diluted 1:500 with waterwithout dead corners (i.e., 1 bottle diluted with 125 kg of water), sprayed 2-3times a week, used continuously for a month, then switch.

3.Under the strictimplementation of this plan, other insects in the pig farm, such as mosquitoes,spiders, ticks, lice, and mites in the environment, will also be killed.

ProfessorFang Binghu, South China Agricultural University and Vice President of DHNDivision, Wens Food Group Co., Ltd.

Professor FangBinghu from South China Agricultural University and Vice President of the DHNDivision of Wens Food Group Co., Ltd., introduced the basic knowledge ofdisinfectants and explained the disinfectants recommended by the Ministry ofAgriculture and Rural Affairs for African Swine Fever and their usage methods.He reminded breeders to make good use of isolation zones. He gave suggestionson specific measures for disinfection and isolation in pig farms under thesituation of African Swine Fever. Among them, thefocus is on environmental disinfection. He reminded pig farms to pay attentionto the decontamination and disinfection of feed, disinfection of drinkingwater, and improving the immune system of pigs.

SpecificMeasures for African Swine Fever in Enterprises and Successful Resumption ofProduction Experience

DingWeimin, Technical Director of Anhui Antai Agricultural Group

Ding Weimin, theTechnical Director of Anhui Antai Agricultural Group, shared the methods forthe prevention and control of African Swine Fever (ASF) in Antai Agriculture:

1.The company established an African SwineFever prevention and control team.

2.Signed a commitment letter for theprevention and control of African Swine Fever.

3.The business division issued documentsfor the prevention and control of African Swine Fever.

4.The pig farm established an ASFprevention and control team led by the farm director.

5.Set up responsible persons for differentareas and farms, and all employees signed a commitment letter.

6.The urgent construction and support ofbiosecurity prevention and control facilities and equipment.

7.Publicize and implement the documents ofthe Ministry of Agriculture and Rural Affairs at all levels.

8.Supervise at all levels, seize typicalcases, and spread positive energy.

9.The company and the pig farm set upspecial assessments for African Swine Fever.

10.Set up a special fund of 2 million forthe prevention and control of African Swine Fever, and implement phasedrewards.

11.Amoeba management and subjectiveinitiative (virtual equity, participate in profit distribution according toproportion).

12.Antai culture: family culture, executionculture, and achievement culture (with pigs, home, and Antai).

He stated that the approach of AntaiAgriculture is mainly very meticulous and wellimplemented. There are detailed regulations and special supervision forpersonnel shower and disinfection centers, vehicle disinfection, and othermeasures. He also focused on explaining the disinfection details of high-riskmarket pig pulling vehicles and feed vehicles. In summary: there are millions of ASF prevention measures, but thefirst is to implement and execute. Cut off, cut off, and cut off again, andexecute, execute, and execute again!

ShiZengbin, National Technical Service Director of DHN Division, Wens Food GroupCo., Ltd.

Shi Zengbin, theNational Technical Service Director of the DHN Division at Wens Food Group Co.,Ltd., shared the experience of successfully resuming production in pig farmsafter an outbreak of African Swine Fever.

Each pig farm must seriously reflect on thesource of its own epidemic, identify any past vulnerabilities, and takemeasures to fill the gaps, upgrade hardware, and improve management. Theoverall environment is very important! Before restocking, the terminaldisinfection of the pig houses must be comprehensive, involving thoroughcleaning, disinfection, fumigation, and drying, and even repeating theoperations 2 or 3 times. It is crucial to use scientific testing methods toevaluate the effectiveness of the disinfection. For frontline operational staff and technical personnelfighting against the severe epidemic of African Swine Fever, the currentpractices and knowledge are far from sufficient. They must undergo systematictraining and strict assessment. Both the software and hardware of the pig farmmust be robust.

During an interview with "China AnimalHealth Care," Shi Zengbin mentioned that some pig farms in China that haveexperienced African Swine Fever are attempting to resume production. According to his understanding, about one-third of thepig farms that are trying to resume production have been successful, and theseare all farms with a scale of more than a thousand pigs.

ZhanSonghe, Deputy Director of the Anhui Provincial Animal Disease Prevention andControl Center, gave a report titled "Main Methods and Precautions forAfrican Swine Fever Detection".

ResearcherCai Gengyuan, Deputy Director of the National Engineering Technology ResearchCenter for Pig Breeding, gave a report titled "Key Areas to Focus on inPig Breeding under the African Swine Fever Epidemic."

LiuXiuli, Deputy Secretary-General of the China Veterinary Association, presidedover the meeting.

ZhuLiangqiang, Director of the Anhui Provincial Animal Disease Prevention andControl Center, presided over the meeting.