非洲猪瘟的流行现状

非洲猪瘟是由非洲猪瘟病毒引起的猪烈性传染病,严重危害养猪业的健康发展,一旦暴发疫情,不但会对本国造成重大经济损失,甚至影响国际贸易。本文从非洲猪瘟的流行现状入手,阐述非洲猪瘟在世界各国的流行情况,以期为该病的监测防控工作提供借鉴。     

载体介导的猪瘟病毒囊膜蛋白疫苗的研制现状

猪瘟病毒(CSFV)是一种常见的猪场感染病毒,常引起猪瘟,其防治疫苗研制备受关注。囊膜蛋白是一种有效的疫苗候选分子,本文综述伪狂犬病毒(rPRV-E2)、鸡痘病毒(rFPV-E0/E2)、Semliki森林病毒(rSFV-E2)、水疱性口炎病毒(rVSV-E2)、猪痘病毒(rSPV-E2)、腺病毒(rAdV-E2)、牛痘病毒(rVV-E2)、猪繁殖和呼吸综合征病毒(rPRRSV-E2)、杆状病毒(rBuV-E2)、猪霍乱沙门氏菌(rSc-E2)、鼠伤寒沙门氏菌(rSt-E2)、干酪乳杆菌(rLc-VP2-E290/E2-Tα1)、根癌农杆菌(rAt-E2)和酵母(rPP-E2)等载体介导的CSFV囊膜蛋白疫苗的构建及其免疫机制等方面研制现状。     

拉沙热疫苗研究进展

拉沙热是由拉沙病毒(Lassa virus, LASV)引起的一种急性传染病,主要由啮齿类动物传给人. 西非是拉沙热最主要的流行区,该地区每年有几十万人患病,数千例死亡.由于LASV的高致病性,被列为潜在生物战剂,当前无获批的拉沙热疫苗.研究表明传统的灭活疫苗免疫保护效果不理想,LASV基因重组的复制增殖型病毒载体疫苗、复制缺陷型病毒载体疫苗和DNA疫苗等新型疫苗显示较好的发展前景. 但是这几种新型疫苗仍处于临床预试验阶段或临床试验阶段.     

艾滋病疫苗的研究进展

人类免疫缺陷病毒(Human immunodeficiency virus，HIV)仍然以每天感染15000人的速度快速扩散传播，95％以上的HIV感染者系发生在发展中国家，迄今为止，宣传教育及对高危行为的干预仅起到减缓传播速度，而无法止其流行，高效抗病毒疗法对大多数感染者来说价格昂贵并且过于复杂，此外，还不能达到清除体内病毒的目的。在这种情况     

HIV疫苗临床试验研究进展

近年来虽然艾滋病防治取得了巨大进展,HIV疫苗依然是人类彻底战胜艾滋病的重要"武器".HIV疫苗的研发历程坎坷,多种技术路线的疫苗进入临床试验阶段,但尚未获得成功.本文通过查阅US Clinical Trials数据库(clinicaltrials.gov)和中国药物临床试验登记与信息公示平台数据库,根据疫苗的技术路线...     

脑膜炎球菌共轭疫苗在非洲人群中的应用

该研究纳入1500例儿童及青年人,分别注射了脑膜炎球菌共轭疫苗及多聚糖四价脑炎球菌疫苗,结果显示,脑膜炎球菌共轭疫苗引出的抗体滴度为78％-96％,明显高于应用多聚糖四价脑炎球菌疫苗受试者（The New England Journal of Medicine 2011,6月16日）。     

狂犬病毒分子生物学和各类疫苗的研究进展

<正> 狂犬病是由狂犬病毒引起的世界性人兽共患性疾病。我国发病率高,一旦发病,100％死亡。目前控制该病只有依赖疫苗。由于该病潜伏期长,疫苗既可用于预防,亦可用于被带狂犬病毒的动物(中国以犬为主)咬伤后的防制发病。 一、狂犬病毒的分子生物学 (一)病毒的形态、结构和基因:狂犬病毒(RabiesVirus,RV)属弹状病毒科(Rbaldo Viridae),LyssaVirus 属。病毒形态似子弹,长约 180nm,直径为75nm,其头端为半球形,末端为平行。病毒外壳为一紧密完整的脂蛋白双层包膜,表面嵌有 1000多个     

日本脑炎DNA疫苗研究进展

由于传统的灭活和减毒活疫苗在预防日本脑炎病毒(JEV)感染中的广泛应用,部分JEV感染的发生和流行得到了有效控制.但是病毒灭活疫苗制备起来费用较高、不能诱导长期的免疫力、更重要的是容易带来超敏反应的风险,同时病毒减毒活疫苗相对不稳定、毒力有可能回升[1].     

ASFV-G-∆I177L as an Effective Oral Nasal Vaccine against the Eurasia Strain of Africa Swine Fever

The African swine fever virus (ASFV) is currently causing a pandemic affecting wild and domestic swine from Western Europe to Asia. No commercial vaccines are available to prevent African swine fever (ASF), resulting in overwhelming economic losses to the swine industry. We recently developed a recombinant vaccine candidate, ASFVG-ΔI177L, by deleting the I177L gene from the genome of the highly virulent ASFV strain Georgia (ASFV-G). ASFV-G-ΔI177L has been proven safe and highly efficacious in challenge studies using parental ASFV-G. Here, we present data demonstrating that ASFV-G-ΔI177L can be administered by the oronasal (ON) route to achieve a similar efficacy to that of intramuscular (IM) administration. Animals receiving ON ASFV-G-ΔI177L were completely protected against virulent ASFV-G challenge. As previously described, similar results were obtained when ASFV-G-ΔI177L was given intramuscularly. Interestingly, viremias induced in animals inoculated oronasally were lower than those measured in IM-inoculated animals. ASFV-specific antibody responses, mediated by IgG1, IgG2 and IgM, do not differ in animals inoculated by the ON route from that had IM inoculations. Therefore, the ASFV-G-ΔI177L vaccine candidate can be administered oronasally, a critical attribute for potential vaccination of wild swine populations.     

Deletion of an African Swine Fever Virus ATP-Dependent RNA Helicase QP509L from the Highly Virulent Georgia 2010 Strain Does Not Affect Replication or Virulence

African swine fever virus (ASFV) produces a lethal disease (ASF) in domestic pigs, which is currently causing a pandemic deteriorating pig production across Eurasia. ASFV is a large and structurally complex virus with a large genome harboring more than 150 genes. ASFV gene QP509L has been shown to encode for an ATP-dependent RNA helicase, which appears to be important for efficient virus replication. Here, we report the development of a recombinant virus, ASFV-G-∆QP509L, having deleted the QP509L gene in the highly virulent field isolate ASFV Georgia 2010 (ASFV-G). It is shown that ASFV-G-∆QP509L replicates in primary swine macrophage cultures as efficiently as the parental virus ASFV-G. In addition, the experimental inoculation of pigs with 10² HAD₅₀ by the intramuscular route produced a slightly protracted but lethal clinical disease when compared to that of animals inoculated with virulent parental ASFV-G. Viremia titers in animals infected with ASFV-G-∆QP509L also had slightly protracted kinetics of presentation. Therefore, ASFV gene QP509L is not critical for the processes of virus replication in swine macrophages, nor is it clearly involved in virus replication and virulence in domestic pigs.     

猪沙门菌疫苗研究进展

沙门菌病是一种重要的人兽共患病,我国是猪肉消费大国,受污染的猪肉是沙门菌病的主要来源,目前国内外有许多猪沙门菌疫苗在被使用。在欧洲现流行的猪沙门菌疫苗为减毒活疫苗,能减少沙门菌在猪体内的定殖,并能在二次免疫后诱导高效的抗体免疫应答。接种疫苗并非万无一失,问题就在于,当沙门菌的血清型与疫苗的抗原不相同时,对沙门菌的防控效果就较差,现阶段对猪疫苗交叉保护研究较少。本文就猪沙门菌疫苗的研究进展进行了综述。     

Development and In Vivo Evaluation of a MGF110-1L Deletion Mutant in African Swine Fever Strain Georgia

African swine fever (ASF) is currently causing an epizootic, affecting pigs throughout Eurasia, and causing significant economic losses in the swine industry. ASF is caused by African swine fever virus (ASFV) that consists of a large dsDNA genome that encodes for more than 160 genes; few of these genes have been studied in detail. ASFV contains four multi-gene family (MGF) groups of genes that have been implicated in regulating the immune response and host specificity; however, the individual roles of most of these genes have not been well studied. Here, we describe the evaluation of the previously uncharacterized ASFV MGF110-1L open reading frame (ORF) using a deletion mutant of the ASFV currently circulating throughout Eurasia. The recombinant ASFV lacking the MGF110-1L gene (ASFV-G-ΔMGF110-1L) demonstrated in vitro that the MGF110-1L gene is non-essential, since ASFV-G-ΔMGF110-1L had similar replication kinetics in primary swine macrophage cell cultures when compared to parental highly virulent field isolate Georgia2007 (ASFV-G). Experimental infection of domestic pigs with ASFV-G-ΔMGF110-1L produced a clinical disease similar to that caused by the parental ASFV-G, confirming that deletion of the MGF110-1L gene from the ASFV genome does not affect viral virulence.     

Deletion of the ASFV dUTPase Gene E165R from the Genome of Highly Virulent African Swine Fever Virus Georgia 2010 Does Not Affect Virus Replication or Virulence in Domestic Pigs

African swine fever (ASF) is a frequently lethal disease of domestic and wild swine currently producing a pandemic affecting pig production in Eurasia. The causative agent, ASF virus (ASFV) is a structurally complex virus with a large genome harboring over 150 genes. One of them, E165R, encodes for a protein belonging to the dUTPase family. The fine structure of the purified protein has been recently analyzed and its dUTPase activity tested. In addition, it has been reported that a BA71 mutant virus, adapted to growth in Vero cells, lacking the E165R gene presented a drastic decreased replication in swine macrophages, its natural target cell. Herein, we report the development of a recombinant virus, ASFV-G-∆E165R, harboring the deletion of the E165R gene from the genome of the highly virulent field isolate ASFV Georgia 2010 (ASFV-G). Interestingly, ASFV-G-∆E165R replicates in primary swine macrophage cultures as efficiently as the parental virus ASFV-G. In addition, ASFV-G-∆E165R also replicates in experimentally inoculated domestic pigs with equal efficacy as ASFV-G and produced a lethal disease almost indistinguishable from that induced by the parental virus. Therefore, results presented here clearly demonstrated that E165R gene is not essential or important for ASFV replication in swine macrophages nor disease production in domestic pigs.     

The Efficacy of Disinfection on Modified Vaccinia Ankara and African Swine Fever Virus in Various Forest Soil Types

African swine fever (ASF) has become a global threat to the pig industry and wild suids. Within Europe, including Germany, affected wild boar populations play a major role. Fencing and carcass removal in combination with the reduction in environmental contamination are key to control further spread. The handling of the ASF virus (ASFV) is restricted to high-containment conditions in Germany. According to the regulation of the German Veterinarian Society (DVG), modified vaccinia Ankara virus (MVAV) is the virus of choice to determine the efficacy of disinfection for enveloped viruses. The aim of this study was to use the MVAV as a guide to select the best possible disinfectant solution and concentration for the inactivation of ASFV in soil. Both viruses were tested simultaneously. In this study, two layers (top and mineral soil) of soil types from six different locations in Saxony, Germany, were collected. The tenacity of ASFV and MVAV were tested at various time points (0.5 to 72 h). The capabilities of different concentrations of peracetic acid and citric acid (approx. 0.1 to 2%) to inactivate the viruses in the selected soil types with spiked high protein load were examined under appropriate containment conditions. Around 2–3 Log₁₀ (TCID₅₀) levels of reduction in the infectivity of both ASFV and MVAV were observed in all soil types starting after two hours. For MVAV, a 4 Log₁₀ loss was recorded after 72 h. A total of 0.1% of peracetic acid (5 L/m²) was sufficient to inactivate the viruses. A 4 log₁₀ reduction in the infectivity of MVAV was noticed by applying 1% citric acid, while a 2 log₁₀ decline was recorded with ASFV. In conclusion, comparing MVAV to ASFV for efficacy screening of disinfectant solutions has revealed many similarities. Peracetic acid reduced the infectivity of both viruses independently of the soil type and the existence of a high organic soiling.     

Prevention and Control Strategies of African Swine Fever and Progress on Pig Farm Repopulation in China

African swine fever (ASF) is a devastating disease in domestic and wild pigs. Since the first outbreak of ASF in August 2018 in China, the disease has spread throughout the country with an unprecedented speed, causing heavy losses to the pig and related industries. As a result, strategies for managing the disease are urgently needed. This paper summarizes the important aspects of three key elements about African swine fever virus (ASFV) transmission, including the sources of infection, transmission routes, and susceptible animals. It overviews the relevant prevention and control strategies, focusing on the research progress of ASFV vaccines, anti-ASFV drugs, ASFV-resistant pigs, efficient disinfection, and pig farm biosecurity. We then reviewed the key technical points concerning pig farm repopulation, which is critical to the pork industry. We hope to not only provide a theoretical basis but also practical strategies for effective dealing with the ASF epidemic and restoration of pig production.     

Efficacy of Liming Forest Soil in the Context of African Swine Fever Virus

Since September 2020, Germany has experienced the first ever outbreak of African swine fever (ASF). The first known cases occurred exclusively in wild boar in forest areas in Brandenburg and Saxony; in July 2021, infected domestic pigs were also confirmed for the first time. As wild boar are considered the main reservoir for the virus in the European region, an effective interruption of this infection chain is essential. In particular, the removal and safe disposal of infected carcasses and the direct disinfection of contaminated, unpaved ground are priorities in this regard. For the disinfection, highly potent as well as environmentally compatible disinfectants must be used, which are neither influenced in their effectiveness by the soil condition nor by increased organic contamination. Thus, in this study, slaked lime, milk of lime and quicklime (1% to 10% solutions) were selected for efficacy testing against the test virus recommended by the German Veterinary Society (DVG), Modified Vaccinia Ankara virus (MVAV), and ASF virus (ASFV) in conjunction with six different forest soils from Saxony in two different soil layers (top soil and mineral soil) each. In summary, 10% of any tested lime type is able to inactivate both MVAV and ASFV under conditions of high organic load and independent of the water content of the soil. At least a 4 log reduction of the virus titer in all tested forest soil types and layers and by all applied lime types was observed. In conclusion, the high efficacy and suitability of all tested lime products against both viruses and in the presence of high organic load in forest soil can be confirmed and will help to control ASF spread.