猪繁殖与呼综合症(蓝耳病)生物安全控制

1、Biosecurity protocols for the prevention of spread of porcine reproductive and respiratory syndrome virus预防猪繁殖与呼吸综合症病毒（蓝耳病病毒）传播的生物安全条款Swine Disease Eradication Center University of Minnesota College of Veterinary Medicine明尼苏达大学兽医学院，猪病净化中心目录Introduction 前言2Virus overview 病毒概括2Routes of Spread and Pro

2、tocols of Biosecurity 传播途径和生物安全方案3Direct routes (live animals and semen) 直接途径（活体动物和精液）3Indirect routes 间接途径4Facilities 圈舍设施4Needles 针头6Transport vehicles 运输车辆6Personal 人员7Fomites 污染物9Insects 昆虫9Aerosols 空气方式 10Miscellaneous 其它方面 14Concluding remarks 结语 15Suggested reading 推荐阅读15Introduction 前言Porcin

3、e reproductive and respiratory syndrome (PRRS) is an economically significant disease of swine that has been estimated to cost the US industry approximately $560 million a year. Preventing the spread of PRRSV within and between pig populations is a critical component of a farms disease control progr

4、am. To aid in controlling the spread of this agent, this manual provides a summary of data from experiments conducted from our group at the University of Minnesota that were specifically designed to identify the routes of PRRSV transmission and to develop protocols of biosecurity to reduce this risk

5、. All protocols have been, and continue to be validated during angoing experiment that has been in process over the past 2 years at our Swine Disease Eradication Center (SDEC) production region model farm. The authors of this manual continue to practice these protocols and procedures on a daily basi

6、s; therefore, as of this writing our confidence in their ability to prevent PRRDV spread is very high. We hope that swine veterinarians can utilize this information to help their clients develop effective biosecurity programs for sustainable PRRS control.猪繁殖与呼吸综合症病是一种能够引起养猪产业重大经济损失的疾病，其在美国每年造成的经济损失被

7、认为有 5.6 亿美元。预防此病毒在种群内和种群间传播成为了猪场疾病控制 计划的重要组成部分。为了辅助这一进程的开展，明尼苏达大学特别设计了实验来研究猪繁 殖与呼吸综合症病毒的传播途径，然后得到了用生物安全这一方法来减少疾病风险的方案， 并最终把方案集合成这本手册。所有的方案在我们的猪病净化中心（SDEC）生产示范场内 在过去的 2 年中已经被验证或者正在验证是成功有效的，手册的作者们每天都在实践着这些 条款和规程；因此，我们非常有信心利用这本手册能够成功预防猪繁殖与呼吸综合症，同时， 我们期望猪兽医工作者能够利用这本书为他们服务的猪场提供行之有效的生物安全方案，进 而实现对猪繁殖与呼吸综合症

8、的掌控。Virus overview 病毒概括Prior to discussing how the virus spreads between farms and within populations of pigs, it is important to understand its host range and biochemical characteristic. Based on the excellent work of several investigators, we know that the etiologic agent of PRRS, porcine reproduc

9、tive and respiratory syndrome virus (PRRSV), is a single-stranded positive sense RNA virus classified in the order Nidovirales, family Arteriviridae and genus Arterivirus. PRRSV has also been shown to be a host-species virus, Capable of infecting only pigs. therefore, no other mammalian, insect or a

10、vian species can serve as biological vectors of the virus. In regards to its capability for survival outside of the pig, PRRSV is susceptible to high temperatures, changes in pH(<6 and >7.65), and prolonged exposure to UV light as well as chemical inactivation. While PRRSV can survive for mont

11、hs to years when frozen (-20 degrees C), as temperature increase, its survivability decreases. For example, the virus can survive for 6 days at 21 degrees C, for 24hours at 37 degrees C and for only 20 minutes at 56 degrees C. in addition, when kept moist, the virus is viable out to 11 days.在讨论病毒是怎样

12、在猪场间和猪场内进行传播之前。必须首先了解该病毒的宿主范围和生物化学属性要。通过多名科研工作者的成功探索，我们知道猪繁殖与呼吸综合症的病原为 猪繁殖与呼吸综合症病毒，这种病毒是单股正链 RNA 病毒，其被归类为巢状病毒属动脉炎 病毒科中的动脉炎病毒。猪繁殖与呼吸综合症病毒是一种宿主特异性病毒，仅能感染猪，不 感染其它哺乳动物。昆虫和禽类能够作为病毒的生物传播媒介。在考虑病毒在猪体外的生存 能力时，发现这种病毒对高温、PH 值（<6 和>7.65）、紫外线和化学灭活剂非常敏感。然而， 在冷冻（-20）的条件下病毒能够存活数月甚至数年，随着温度提高，病毒成活的几率降 低。例如病毒能够在

13、 21存活 6 天，在 37存活 24 小时，在 56存活 20 分钟，另外，当病毒处在潮湿的环境中时其能够保持活力到 11 天。Routes of Spread and Protocols of Biosecurity 传播途径和生物安 全方案Direct routes (live animals and semen) 直接途径（活体动物和精液）As stated, pigs are the only animal capable of becoming infected with PRRSV. Once infection occurs, the virus can be shed fro

14、m persistently infected pigs via blood, saliva, milk and colostrum, urine and feces, as well as contaminated semen, and therefore, purchasing genetic material fromnaïve sources that are monitored on a regular basis is critica（lcrucial）. Vet-to-Vet communicationto review the current health of th

15、e herd prior to purchase is recommended, followed by quarantine and testing of animals. The following are examples of protocols to reduce the risk of PRRSV entry to farms via the introduction of genetic material:开始已经提到，猪是唯一能够感染猪繁殖与呼吸综合症病毒的动物。一旦发生感染，猪只就持续的通过血液、唾液、乳汁（初乳）、尿液和粪便进行排毒，因此，从定期进行监控 的阴性种猪场引入种

16、畜变的非常的重要。有时候，在购买之前，兽医之间的沟通以评估目前 猪群的健康状态非常必要，并且在接下来的动物隔离和检测阶段，兽医同样应当保持这样的 沟通。下面是引进种畜过程中为降低感染猪繁殖与呼吸综合症病毒风险而执行的程序实例：l Isolation 隔离ü An isolation (quarantine) facility is a critical component of a PRRSV biosecurity program.Isolation facilities should be located greater than 120 meters from the bree

17、ding herd and ideally, off-site. Incoming stock should be kept separate from resident stock for a minimum of 30 days. Animals should be monitored daily for clinical signs by farm personnel. The herd veterinarian should remain in close communication with the seedstock suppliers veterinarian during th

18、is period in case the onset of a disease is suspected in the source population or the animals in quarantine.隔离舍是猪繁殖与呼吸综合症病毒生物安全计划的重要组成部分，隔离舍应当位于种群 120 米以外，理想状态下应当在场外另一处地点，引入的种畜和原来饲养的种群至少需要隔离 30 天。期间应当每天观察种畜有无临床症状。并使引入猪场兽医 与种畜供应场兽医紧密保持沟通，以便在引种猪群和隔离猪群出现可疑疾病时采取 果断措施。l Testing 检测ü Replacement stock

19、 should be blood tested 24-48 hours after arrival to the isolation facility as well as 5-7 days prior to their entry to the breeding herd. Once infected, PRRSV RNA can be detected in the bloodstream 24 hours post-infected, PRRSV RNA can be detected in the bloodstream 24 hours post-infection; therefo

20、re, testing of samples by PCR is recommended to enhance detection of peracute infections. Samples collected late in the isolation period can also be tested by ELISA for the presence of PRRSV antibodies.引入的种畜应当在到达隔离舍 24-48 小时后进行采血检测，同样，在转移至配种舍前 5-7 天也需要采血检测。猪只一旦感染猪繁殖与呼吸综合症病毒，病毒 RNA 就 能够在感染 24 小时后的猪只血

21、液中检测到；因此，多聚酶链式反应（PCR）方法 在快速检测急性感染方面非常有用。隔离期间，后续采集的样品同样能够运用酶联 免疫吸附试验（ELISA）检测样本中是否存在猪繁殖与呼吸综合症病毒抗体。ü With the advent of the blood swab technique, AI centers can proactively monitor their status via PCR. With the ability of diagnostic labs to provide “one day turnaround” of PCR results, producers

22、and veterinarians can receive semen validated as PRRS-negative in real-time and safely introduce it to their herds.运用最近的血液棉签采样方法，人工授精中心能够利用 PCR 来提前监测公猪（精液）的健康状态。既然实验室能够在一天内通过 PCR 的方法得到检测结果，猪场 主和兽医能够实时接收经过验证猪繁殖与呼吸病毒阴性的精液到猪场，并运用到猪 群之中。Blood testing isowean gilts in quarantine血样检测隔离期的早期断奶后备母猪Indirect r

23、outes 间接途径PRRSV can be mechanically transmitted in a number of ways. The following section will review routes of transmission and outline the biosecurity protocols designed to help prevent spread via these routes.猪繁殖与呼吸综合症病毒能够通过各种方式进行传播，在下面的部分将会概述病毒传播的途径并列出为防止病毒通过这些途径进行传播的生物安全规程。Facilities 圈舍设施Swine

24、 facilities should be managed using all-in, all-out (AIAO) pig flow, thereby reducing the spread of PRRSV from older, infected pigs to younger, naïve animals. In conjunction with AIAO flow, it is important to properly sanitize the facilities before introducing susceptible animals. Examples of t

25、he steps required to sanitize facilities that housed PRRSV-positive animals are as follows:猪场应当采用全进全出的饲养模式来减少猪繁殖与呼吸综合症病毒从成年猪群传播到幼龄猪或仔猪，通过这种方式，可以在引入易感动物之前把所有设施进行彻底的消毒。下面 给出了曾经饲养过猪繁殖与呼吸综合症病毒阳性猪的圈舍所需要的消毒程序：l All organic material (feces, urine feed, bedding and body fluids) should be completely removed

26、and the surfaces power washed. Special attention should be paid to the gating, feeders, waterers, slats in the floors and any other “cracks or crevices” where such material could be harbored and missed.所有有机物质（粪便，尿液，饲料，垫草和体液）都应当全部移走并用高压水枪进行冲洗，特别注意门控，料槽，饮水器，漏缝地板和其它有裂缝及缝隙而常常被忽略并能窝 藏病原的地方。Removal of deb

27、ris is critical for proper sanitation of facilities移走多余的碎屑对合理消毒圈舍至关重要l Once clean, an efficacious disinfectant should be applied throughout the pen area. Some examples of products proven to be efficacious against PRRSV are quaternary ammonium + glutaraldehyde mixtures (Synergize) and modified potass

28、ium monopersulfate (Virkon). These products should be applied at a 0.8% and 1% concentration, respectively for a minimum of 2 hours. The application of disinfectants via of foamer allows for better visualization of where product has been applied and also prolongs the contact between the chemicals an

29、d the surfaces.清洗之后，需要应用有效的消毒药物对圈舍进行消毒。一些产品被认为对猪繁殖与呼吸综合症病毒有效，例如季铵+戊二醛混合成分（增效作用）和单过硫酸氢钾（卫可），这 些产品应当在有效浓度为 0.8%-1%应用，且至少需要作用 2 个小时。消毒剂通过泡沫喷 雾的形式使用，这样能够更清晰的看到哪些部分应用了消毒剂，而哪些部分没有，同时， 通过这种方法能够延长消毒剂有效成分与需要消毒的表面的接触时间。Application of disinfectants via a foamer enhances their effectiveness通过泡沫的形式应用消毒剂能够增强消毒效果l

30、 Following cleaning, the facility must be allowed adequate downtime or drying time after disinfection. This is the most important step in the sanitation protocol for complete inactivation of the virus.消毒过后，猪舍和设施必须有充足的空置和干燥时间，这是消毒程序中完全灭活病毒的最为重要的步骤。Properly sanitized nursery room 合格消毒过的保育舍Needles 针头On

31、ce a pig is infected, the quantity of PRRSV in the blood stream typically reaches high levels. Therefore, injection of consecutive animals using a contaminated needle can result in hematogenous spread of the virus. To reduce this risk, it is recommended to change needles between sow during third tri

32、mester injections or utilize “needle-free” technology.一旦有一只猪感染，猪繁殖与呼吸综合症病毒在血液中就能够达到很高的滴度，因此，应用一个病毒污染的针头，连续对动物进行注射，病毒就能通过血液的形式进行传播，为了减少 这一风险，在为怀孕后 1/3 阶段的母猪进行注射的时候推荐更换针头，或者应用无针头的技 术/设备进行注射。Transport vehicles 运输车辆PRRSV can be spread to susceptible animals following contact with contaminated transport

33、vehicles. Therefore, as with facilities, stringent compliance with cleaning/disinfection and drying protocols is critical for sanitizing the trailers of transport vehicles. Potential risk point in the cab of the truck (pedals, floor mates, etc) can be effectively sanitized using disinfectant spray,

34、such as Lysol. In regards to trailers:通过接触污染的交通工作，猪繁殖与呼吸综合症病毒即能够使易感动物发生感染。所以，对于各种设施，严格的遵循清洁/消毒并干燥的程序对处理各种各样的车辆就相当重要，卡车 潜在风险位置驾驶室（踏板，脚垫等），应当运用有效的消毒剂进行喷洒消毒，如来苏儿。 对于拖车：l All organic material (faces, urine, feed, bedding, ect) should be removed. Special attention should be paid to “hard to reach” sites,

35、 such as corners of trailers, gate hinges/latches, etc where this material could be harbored.所有的有机物（粪便，尿液，饲料，垫草等）都应当被移除，特别注意那些不容易清理的地方，例如易残留有机物质的车辆的各个角，门的拉手等区域。Contaminated transport can serve as a source of PRRSV infection of naïve pigs污染的运输车辆能够作为猪繁殖与呼吸综合症病毒传播给阴性猪群的载体l Once clean, efficacious

36、disinfectants should be applied to the vehicle using previously described concentrations, periods of contact and method of application.此后用有效的消毒药品以合理的浓度、有效消毒时间和科学的方法对车辆进行消毒。Drying is the most important component of a transport sanitation program干燥是车辆消毒过程中最重要的步骤l Following sanitation, the vehicle must

37、 be allowed adequate drying time after disinfection. As with facilities, this is the most important step in the sanitation protocol to completely inactivate the virus. The use of high-volume warm air can decrease the amount of time needed for drying. The thermo-assisted drying and decontamination (T

38、ADD) system developed by PIC is recommended to achieve a dry trailer in the shortest amount of time. Studies have indicated that 120 minutes of high volume warm air applied via the TADD method can effectively remove PRRSV from contaminated surfaces in transport trailers.消毒过后，车辆需要足够的干燥时间，对于各种设施，干燥也是消

39、毒过程中使病毒完全灭活的重要步骤。PIC 公司研发的加热干燥和净化系统（TADD）能够在最短的时间内达 到干燥的目的。研究表明，TDD 通过在 120 分钟的高通量加热空气过程能够有效清除车 辆表面的猪繁殖与呼吸综合症病毒。Personal 人员The hands, coveralls and boots of personnel can serve as mechanical vehicles for PRRSV. Below are protocols to reduce the risk of PRRSV spread via these routes:工作人员的手，工作服和靴子能够作为

40、猪繁殖与呼吸综合症病毒的载体，下面几种工作方案能够减少猪繁殖与呼吸综合症病毒通过人员途径进行传播的风险。Entry protocols 进场程序l Down time 隔离时间ü Personnel should practice one night of downtime before entering a farm. Research has shown that extended periods of downtime are not necessary for this agent.在进入猪场前隔夜的隔离时间需要严格的执行。同时，研究表明多余的隔离时间没有必要。l Showe

41、r in-shower out 出入淋浴ü Shower protocols have been proven to successfully decontaminate personnel contaminated with PRRSV prior to entry. The use of such a procedure upon entry to the system each day is recommended.淋浴已经被证实是一条成功去除人身体上猪繁殖与呼吸综合症病毒的有效方案。每天进入生产区之前进行淋浴被认为相当有用，并应当严格执行。l Danish entry sys

42、tem 丹麦进入方法ü This system utilizes the changing of coveralls and boots plus the washing of hands in designated areas prior to entering the animal air space and has been demonstrated to be very effective for reducing the risk of PRRSV spread by personnel between sites and buildings.这种方法要求人们在进入动物生产

43、区域之前需要在特定的区域更换工作服、靴子并进行洗手。而且这种方法被认为能够有效的减少猪繁殖与呼吸综合症病毒在不同地 点和不同建筑物间进行传播。Hands 手l Gloves 手套ü The use of gloves can help prevent transfer of virus. Gloves should be changed regularly, I.e. between litters.戴手套能够有效预防病毒的传播，手套也需要定期更换，例如接产不同窝仔猪时。l Sanitizers and hand washing 消毒剂和洗手ü Frequent hand

44、washing and use of sanitizers that contain iodine can successfully remove virus from hands.经常的洗手，或者用含有碘的消毒剂进行洗手能够有效的清除/杀死手上的病毒。Coveralls 工作装l Coveralls 工作服ü Bran-specific coveralls should be available in all facilities and washed routinely. Disposable coveralls are also an option.不同的圈舍需要有不同的工作服

45、装，并且这些服装需要定期的进行清洗，有些时候也可以运用一次性的服装。Boots 靴子l Footbaths 消毒盆ü Use of footbaths can greatly help reduce the risk of PRRSV transfer between groups of pigs. Baths should be changed at least every day to maintain disinfectant efficacy. Chlorine bleach, quaternary ammonium + glutaraldehyde mixtures (Sy

46、nergize) andmodified potassium monopersulfate (Virkon) disinfectants are effective. 运用消毒盆能够有效减少猪繁殖与呼吸综合症病毒在不同猪群之间的传播。消毒液 至少需要每天进行更换以维持消毒剂的有效浓度。如含氯制剂（漂白粉），季铵盐+ 戊二醛混合物（协同作用）和单过硫酸氢钾（卫可）等消毒剂非常有效。l Disposable of facility-specific boots should be used. Boots should never leave the farm and should be power

47、-washed to remove feces from the soles and disinfected routinely.一次性的圈舍专用靴子应当被使用，靴子一定不要离开猪场，并且用完之后需要强力清洗以除去脚底的粪便，并且定期进行消毒。Fomites 污染物Contaminated fomites, such as farm supplies and containers can serve as mechanical vehicles for PRRSV. Therefore, all incoming supplies should be disinfected and allow

48、ed a minimum of 2 hours contact time prior introduction, “Double bagging” supplies is an acceptable method for reducing the risk of spread. A specific room should be used as a disinfection and drying room for fomites (D&D room). All incoming supplies should be placed in this room, disinfected on

49、 all sides and allowed the minimum of 2 hour contract time prior to entry. This can be done using a cold fog mister to create a “fog” of disinfectant. After 5 minutes minimum contact time, the fomites should be rotated, “fogged” on their downside for a minimum of 5minutes and then allowed to remain

50、in the room for a minimum of 2 hours. Quaternary ammonium + glutaraldehyde mixtures (Synergize) and modified potassium monopersulfate (Virkon) disinfectants diluted to 0.8% and 1% respectively are recommended for use in this situation.被污染的物体，比如农场辅助材料和容器能够成为猪繁殖与呼吸综合症病毒传播的媒介，因此，所有外部物品引入猪场之前都应当进行为期至少 2

51、 小时的消毒，“双层包装”是一种减 少病毒传播风险的一种能够接受的方法。猪场内需要有一个特殊的房间作为消毒和干燥的地 方，且所有的引入物品应当放置到这个房间，然后对物品进行每一面至少为 2 小时的消毒处理。可以运用消毒设备使消毒剂呈雾状喷洒，通过 5 分钟的接触时间，物体应当被翻转，对反面再次进行 5 分钟的接触时间并且让引入物品在此房间内至少放置 2 小时。季铵盐+戊二 醛混合液（协同作用）和单硫酸二氰钾（卫可）等消毒剂分别被稀释到 0.8%和 1%被认为是 在这种情况下的有效推荐浓度。Aerosolizing disinfectants in a designated D&D ro

52、om can be useful when sanitizing incoming supplies消毒场外引入物品时雾化的消毒剂在设定的消毒/干燥房间内非常有效Insects 昆虫House flies and mosquitoes can serve as mechanical vectors of PRRSCV and can transport the virus at least 2.4km from an infected farm. The site of retention of the virus in the fly is the GI tract and the rate

53、 of viral decay over time is influenced by quantity ingested and environmentaltemperature. In order to prevent spread of PRRSV via insects the following steps are recommended:家蝇和蚊子能够作为猪繁殖与呼吸综合症病毒的机械传播载体，它们至少能够使病毒传播到感染猪场 2.4 千米以外的地方。病毒在昆虫体内降解失活的时间与昆虫摄入病毒的量和环境 的温度相关。为了减少猪繁殖与呼吸综合症病毒通过昆虫的方式进行传播，下面列出的步骤

54、非常有用。l Screens 滤网/纱窗ü All inlets, windows and areas that could be accessed by insects should be covered with screens. In order to maintain proper ventilation, screens must be cleaned regularly.所有的进口，窗户还有那些昆虫能够进入的地方都应当用安装过滤纱网。为了维持合理的通风，过滤装置需要定期进行清理。The use of insect screen on side wall inlets ha

55、s been demonstrated to significantly reduce insect entry.通过在侧墙上安装昆虫过滤网能够极大的减少昆虫进入生产系统l Insecticides 杀虫剂ü Pyrethrin-based insecticides are highly effective and are commercially available as permises sprays or washes.菊酯类的杀虫剂非常有效，可以用喷洒和清洗的方式应用，成本较低。l Insect bait 诱杀昆虫ü The use of insect bait,

56、i.e. Quik-strike strips, is an effective means to control the number of insects.运用昆虫诱杀器械，比如应用快速粘贴装置是一种有效的控制昆虫数目的方法。l Site management 场内管理ü Cutting the grass and removing weeds surrounding swine facilities as well as removal of standing water are also recommended for eliminating insect breeding

57、areas.剪草和移除场内设施周围杂草的同时处理周围的死水，因为这样清除了昆虫交配配种的区域。Aerosols 空气方式l Airborne spread of PRRSV appears to be isolate-specific. As new highly pathogenic isolates of PRRSV have emerged, such as MN-184 and 1-18-2, their ability to travel long distances via aerosols appears to have increased in contrast to earlier isolates. Recent research has demonstrated the ability of infectious PRRSV to be transmitted by aerosols over a distance of 120 meters. However, preliminary results from exp