A Global Perspective on Oral Vaccination of Wildlife against Rabies.

The long-term mitigation of human-domestic animal-wildlife conflicts is complex and difficult. Over the last 50 yr, the primary biomedical concepts and actualized collaborative global field applications of oral rabies vaccination to wildlife serve as one dramatic example that revolutionized the field of infectious disease management of free-ranging animals. Oral vaccination of wildlife occurred in diverse locales within Africa, Eurasia, the Middle East, and North America. Although rabies is not a candidate for eradication, over a billion doses of vaccine-laden baits distributed strategically by hand, at baiting stations, or via aircraft, resulted in widespread disease prevention, control, or local disease elimination among mesocarnivores. Pure, potent, safe, and efficacious vaccines consisted of either modified-live, highly attenuated, or recombinant viruses contained within attractive, edible baits. Since the late 1970s, major free-ranging target species have included coyotes (Canis latrans), foxes (Urocyon cinereoargenteus; Vulpes vulpes), jackals (Canis aureus; Lupulella mesomelas), raccoons (Procyon lotor), raccoon dogs (Nyctereutes procyonoides), and skunks (Mephitis mephitis). Operational progress has occurred in all but the latter species. Programmatic evaluations of oral rabies vaccination success have included: demonstration of biomarkers incorporated within vaccine-laden baits in target species as representative of bait contact; serological measurement of the induction of specific rabies virus neutralizing antibodies, indicative of an immune response to vaccine; and most importantly, the decreasing detection of rabies virus antigens in the brains of collected animals via enhanced laboratory-based surveillance, as evidence of management impact. Although often conceived mistakenly as a panacea, such cost-effective technology applied to free-ranging wildlife represents a real-world, One Health application benefiting agriculture, conservation biology, and public health. Based upon lessons learned with oral rabies vaccination of mesocarnivores, opportunities for future extension to other taxa and additional diseases will have far-reaching, transdisciplinary benefits.

Digitally driven surgical guide planning.

To investigate the role of a fully digital process in the surgical treatment of mandibular fractures in children. We analyzed a complete dataset from 22 children with mandibular fractures treated with digital surgical assistance. The patient's treatment process included preoperative thin layer CT (Computed Tomography) scanning, computer-aided design (3D reconstruction, virtual reduction, and internal fixation device determination and shaping), and 3D printing (jaw model, bite plate). We used occlusal and shaping plates during surgery to assist in fracture reduction and fixation. During the follow-up, we observed the occurrence of fracture healing, occlusal relationships, opening degrees, and complications in pediatric patients after surgery. Next, we used the 3D overlay function of MIMICS software to compare the preoperative surgical design with postoperative jaw imaging data to evaluate the overall surgical effect. The postoperative imaging data showed good fracture healing, normal occlusion during follow-up, and significant improvement in opening degrees. The mean preoperative opening degree was 23.59 ± 2.89 mm, and the mean postoperative opening degree was 29.82 ± 1.79 mm; there was a significant difference between these two parameters (p < 0.05). There were no complications such as tooth germ injury, nerve injury or fracture block displacement. The postoperative mandibular imaging data was imported into MIMICS software for 3D overlay visualization, and the postoperative mandibular morphology recovery was well-matched with the preoperative design. We measured the average upper deviation (0.65 ± 0.09) mm and the average lower deviation (-0.57 ± 0.14) mm. The fully digital process has a precise, minimally invasive, and safe effect in the surgical treatment of mandibular fractures in children, and the clinical effect is satisfactory.

Evaluation of porcine intestinal organoids as an in vitro model for mammalian orthoreovirus 3 infection.

BACKGROUND: Mammalian orthoreovirus type 3 (MRV3), which is responsible for gastroenteritis in many mammalian species including pigs, has been isolated from piglets with severe diarrhea. However, the use of pig-derived cells as an infection model for swine-MRV3 has rarely been studied. OBJECTIVES: This study aims to establish porcine intestinal organoids (PIOs) and examine their susceptibility as an in vitro model for intestinal MRV3 infection. METHODS: PIOs were isolated and established from the jejunum of a miniature pig. Established PIOs were characterized using polymerase chain reaction (PCR) and immunofluorescence assays (IFAs) to confirm the expression of small intestine-specific genes and proteins, such as Lgr5, LYZI, Mucin-2, ChgA, and Villin. The monolayered PIOs and three-dimensional (3D) PIOs, obtained through their distribution to expose the apical surface, were infected with MRV3 for 2 h, washed with Dulbecco's phosphate-buffered saline, and observed. Viral infection was confirmed using PCR and IFA. We performed quantitative real-time reverse transcription-PCR to assess changes in viral copy numbers and gene expressions linked to intestinal epithelial genes and antiviral activity. RESULTS: The established PIOs have molecular characteristics of intestinal organoids. Infected PIOs showed delayed proliferation with disruption of structures. In addition, infection with MRV3 altered the gene expression linked to intestinal epithelial cells and antiviral activity, and these effects were observed in both 2D and 3D models. Furthermore, viral copy numbers in the supernatant of both models increased in a time-dependent manner. CONCLUSIONS: We suggest that PIOs can be an in vitro model to study the infection mechanism of MRV3 in detail, facilitating pharmaceutical development.

Immunomodulatory effects of canine mesenchymal stem cells in an experimental atopic dermatitis model.

Mesenchymal stem cells (MSCs) have the potential to differentiate into multi-lineage cells, suggesting their future applicability in regenerative medicine and biotechnology. The immunomodulatory properties of MSCs make them a promising replacement therapy in various fields of animal research including in canine atopic dermatitis (AD), a skin disease with 10-15% prevalence. We investigated the immunomodulatory effects of MSCs in an experimental canine AD model induced by Dermatophagoides farinae extract ointment. Canine adipose tissue-derived MSCs (cAT-MSCs) were differentiated into mesodermal cell lineages at the third passage. Alterations in immunomodulatory factors in control, AD, and MSC-treated AD groups were evaluated using flow cytometric analysis, enzyme-linked immunosorbent assay, and quantitative reverse transcription PCR. In the MSC-treated AD group, the number of eosinophils decreased, and the number of regulatory T cells (Tregs) increased compared to those in the AD group. In addition, the immunoglobulin E (IgE) and prostaglandin E2 levels were reduced in the MSC-treated AD group compared to those in the AD group. Furthermore, the filaggrin, vascular endothelial growth factor, and interleukin-5 gene expression levels were relatively higher in the MSC-treated AD group than in the AD group, however, not significantly. cAT-MSCs exerted immunomodulatory effects in an AD canine model via a rebalancing of type-1 and -2 T helper cells that correlated with increased levels of Tregs, IgE, and various cytokines.

Assessment of quality of life after soft tissue resection of head and neck carcinoma and reconstruction with double-paddle peroneal artery perforator free flap.

We aimed to assess the quality of life for head and neck carcinoma (HNC) patients who underwent soft tissue resection and reconstruction with double-paddle peroneal artery perforator (DPAP) free flap. The quality of life was assessed by means of the University of Washington quality of life (UW-QOL) and the 14-item Oral Health Impact Profile (OHIP-14) questionnaires at 12 months postoperatively. Data from 57 patients were retrospectively analysed. Out of these, 51 patients were at TNM stage III or IV. Finally, 48 patients finished and returned the two questionnaires. In the UW-QOL questionnaire, the mean (SD) higher scores were pain 76.5 (6.4), shoulder 74.3 (9.6), and activity 71.6 (6.1), whereas the lower scores were chewing 49.7 (5.2), taste 51.1 (7.7), and saliva (56.7 (7.4). In the OHIP-14 questionnaire, the higher-scoring domains were psychological discomfort (69.3 (9.6) and psychological disability 65.2 (5.8), whereas the lower-scoring domains were handicap 28.7 (4.3) and physical pain 30.4 (8.1). The DPAP free flap significantly improved appearance, activity, shoulder, mood, psychological discomfort, and handicap compared with pedicled pectoralis major myocutaneous flap reconstruction. In conclusion, DPAP free flap for reconstruction of tissue defects after soft tissue resection of HNC significantly improved the patients' QOL compared to pedicled pectoralis major myocutaneous flap reconstruction.

[Analysis of the effect of free posterior lateral peroneal artery perforator flap of lower leg in repairing oropharyngeal cancer].

Objective:To analyze the clinical effect of free posterior lateral peroneal artery perforator flap of lower leg in repairing postoperative defect of oropharyngeal carcinoma. Methods:Thirty-six patients with oropharyngeal carcinoma admitted to the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Bengbu Medical College from June 2016 to June 2019 were analyzed and followed up, eighteen patients were treated with free posterior lateral peroneal artery perforator flap of the lower leg to repair the postoperative defects（experimental group）, and eighteen patients were treated with free forearm flap（control group）. The survival rate of the transplanted flap, the wound stageⅠhealing rate and average hospitalization time were compared between the two groups. Kaplan-Meier method was used to calculate the 1-year and 3-year survival rates of patients after operation, and log-rank test was used to compare the difference between the survival curves of the two groups; The recovery of swallowing and palatopharyngeal closure function of patients in the two groups at 3, 6, 12 and 18 months after operation was calculated and statistically analyzed through the water swallow test and the air blowing method. Results:There was one case of skin flap necrosis in both the experimental group and the control group, and the survival rate was 94.4%. The wound stageⅠhealing rate in the surgical area was 94.4% in both groups. The wound healing rates of the donor area in the experimental group and the control group were 100.0% and 94.4% respectively. The average hospitalization time of the experimental group and the control group was 16.9 days and 17.2 days, respectively, with no significant difference （P>0.05）. The overall survival rates of all patients at 1-year and 3-year were 91.2% and 66.5% respectively; The 1-year and 3-year survival rates of the experimental group and the control group were 94.1%, 69.3% and 88.2%, 63.7%, respectively, and there was no significant difference between the two groups （P>0.05）. The 1-year and 3-year survival rates of P16+ and P16 - patients were 100.0%, 80.0% and 85.7%, 64.3%, respectively, and there was no significant difference between the two groups （P>0.05）. There was no significant difference in the evaluation of swallowing and velopharyngeal closure function between the two groups at 3 and 6 months after operation （P>0.05）, but there was a significant difference at 12 and 18 months after operation （P<0.05）. Conclusion:The anatomic position of the perforating vessels of the free posterior lateral peroneal artery perforator flap of the lower leg is constant, and it can be prepared into single leaf, multi leaf, chimeric and other flaps according to the tissue defect space. And the concealed supply area can be directly drawn to suture. At the same time, the skin flap has strong plasticity. Therefore, the skin flap can be used as a common skin flap to repair the defects after the operation of oropharyngeal carcinoma.

[Application of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma].

OBJECTIVE: To investigate the effectiveness of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma (PGC). METHODS: Between June 2010 and June 2020, 32 patients with advanced local lesions of PGC were treated with extended radical resection. After that, 17 patients were repaired with the free peroneal artery chimeric perforator flaps (trial group) and another 15 patients were repaired with the pedicled pectoralis major myocutaneous flaps (control group). There was no significant difference in gender, age, disease type, histopathological classification, clinical stage, and pathological stage between groups ( P>0.05). The size of skin flap in trial group ranged from 7 cm×6 cm to 12 cm×8 cm and the size of soleus muscle flap ranged from 5 cm×3 cm to 6 cm×4 cm. The donor sites were repaired with skin grafting. The size of the pedicled pectoralis major myocutaneous flaps in control group ranged from 9 cm×6 cm to 14 cm×7 cm. The donor sites were sutured directly. The operation time, survival rate of flap, and postoperative survival of patients were recorded and compared between groups. At 1 year after operation, the University of Washington quality of life (UW-QOL) questionnaire was used to evaluate the quality of life of patients in the two groups, including appearance, shoulder movement, sociability, masticatory function, speech function, and mood. RESULTS: The operations completed successfully. The operation time was (6.19±0.72) hours in trial group and (6.41±0.71) hours in control group, showing no significant difference between groups ( t=-0.863, P=0.395). The survival rate of flap in trial group was 94.1% (16/17); and 1 patient suffered from vascular crisis after operation and was replaced with the pedicled pectoralis major myocutaneous flap. The survival rate of flap in control group was 100%. All grafts survived and the incisions healed by first intention in the two groups. All patients were followed up. The follow-up time was 6-60 months (median, 60 months) in trial group and 7-60 months (median, 60 months) in control group. Cumulative survival rates of patients at 1, 3, and 5 years after operation were 94.1%, 64.7%, and 58.8% in trial group, respectively; 86.7%, 66.7%, and 53.3% in control group, respectively. There was no significant difference in the cumulative survival rate between groups ( χ 2=0.090, P=0.762). According to the UW-QOL questionnaire at 1 year after operation, the scores of appearance, shoulder movement, sociability, and mood in trial group were significantly higher than those in control group ( P<0.05); and there was no significant difference in masticatory function and speech function scores between groups ( P>0.05). CONCLUSION: The peroneal artery perforator has an invariable anatomical relationship. Each perforator emits the muscular branch that nourishes the soleus muscle. Therefore, personalized free peroneal artery chimeric perforator flap can be designed according to the tissue defect, and used to repair the defect after advanced local lesions resection in PGC.

Immunogenicity of an inactivated rabies vaccine for animals derived from the recombinant ERAGS strain.

PURPOSE: The aims of the present study were to evaluate the immunogenicity of an inactivated rabies vaccine based on the ERAGS strain. MATERIALS AND METHODS: The ERAGS virus propagated in Vero cells was inactivated with 3 mM binary ethylenimine for 8 hours. Three types of inactivated rabies vaccines were prepared to determine the minimum vaccine virus titers. Four further types of inactivated rabies vaccines were prepared by blending inactivated ERAGS with four different adjuvants; each vaccine was injected into mice, guinea pigs, and dogs to identify the optimal adjuvant. The immunogenicity of a Montanide (IMS) gel-adjuvanted vaccine was evaluated in cats, dogs, and cattle. Humoral immune responses were measured via a fluorescent antibody virus neutralization method and a blocking enzyme-linked immunosorbent assay. RESULTS: The minimum virus titer of the inactivated rabies vaccine was over 107.0 50% tissue culture infectious doses (TCID50 values)/mL. Of the four kinds of adjuvants, the IMS gel-adjuvanted vaccine induced the highest mean viral neutralizing antibody (VNA) titers of 6.24 and 2.36 IU/mL in guinea pigs and dogs, respectively, and was thus selected as the vaccine for the target animals. Cats, dogs, and cattle inoculated with the IMS gel-adjuvanted vaccine developed protective VNA titers ranging from 3.5 to 1.2 IU/mL at 4 weeks post-inoculation (WPI). CONCLUSION: Our data indicate that cats, dogs, and cattle inoculated with an inactivated rabies vaccine derived from the ERAGS strain developed protective immune responses that were maintained to 12 WPI.

THE PRESENCE OF ANTIBODIES AGAINST PSEUDORABIES VIRUS IN WILD BOARS (SUS SCROFA) IN KOREA.

The control and elimination of pseudorabies (PR) is one of the most important goals in the pig industry. After the first PR outbreak in Korea in 1986, all pigs infected with PR virus (PRV) were removed, and a vaccination program for pigs was implemented. No PR has occurred in Korea since 2010, and vaccination was discontinued after 2013. Information on the seroprevalence of PRV in pigs, including wild boars (Sus scrofa), is important for evaluating the PR status in a country. In this study, 2.65% (28/1057) of the wild boars tested had antibodies against PRV in 2018, indicating that PRV has been circulating continuously in the wild boar population in Korea. Effective means should be implemented to prevent the transmission of PRV between wild and domestic pigs, because the wild boar is a potential reservoir host for PRV.

Role of Oral Rabies Vaccines in the Elimination of Dog-Mediated Human Rabies Deaths.

Domestic dogs are responsible for nearly all the ¼59,000 global human rabies deaths that occur annually. Numerous control measures have been successful at eliminating dog-mediated human rabies deaths in upper-income countries, including dog population management, parenteral dog vaccination programs, access to human rabies vaccines, and education programs for bite prevention and wound treatment. Implementing these techniques in resource-poor settings can be challenging; perhaps the greatest challenge is maintaining adequate herd immunity in free-roaming dog populations. Oral rabies vaccines have been a cornerstone in rabies virus elimination from wildlife populations; however, oral vaccines have never been effectively used to control dog-mediated rabies. Here, we convey the perspectives of the World Organisation for Animal Health Rabies Reference Laboratory Directors, the World Organisation for Animal Health expert committee on dog rabies control, and World Health Organization regarding the role of oral vaccines for dogs. We also issue recommendations for overcoming hesitations to expedited field use of appropriate oral vaccines.

Genotype-specific neutralizing antibody titers against Japanese encephalitis virus genotypes 1 and 3 in horses immunized with a genotype 3 vaccine.

PURPOSE: Japanese encephalitis is one of the most important mosquito-borne and zoonotic diseases in Asia and the Pacific region. Although the dominant Japanese encephalitis virus (JEV) genotype has shifted from G3 to G1 in Korea since 1990, a G3 strain (Anyang 300) has been used in vaccines for horses for almost 40 years. This study aimed to investigate the seroconversion rates and geometric mean titers (GMTs) of virus-neutralizing antibodies (VNAs) against JEV G1 and G3 in horses immunized with the G3 vaccine. MATERIALS AND METHODS: Serum samples of 1,231 horses immunized with the Anyang 300 vaccine were collected in 2018. VNA titers against JEV KV1899 (G1) and Anyang 300 (G3) were measured in all serum samples using the virus neutralization test. Titers were analyzed according to blood sampling time (prior to and following annual revaccination), age, and region. RESULTS: Rates of VNA titer >10 were 45.1% and 77.8% for G1, and 49.1% and 82.9% for G3 in samples taken before and after revaccination, respectively. GMTs of genotype-specific VNAs against JEV G1 and G3 were 8.3 and 11.6 before revaccination and rose to 27.2 and 65.4 following revaccination. Overall sero-positivity did not significantly differ between genotypes, but GMTs significantly differed among genotypes and sampling times. No significant difference was found in GMTs among age groups or regions. CONCLUSION: Genotype-specific neutralizing antibody titers against JEV G1 and G3 differed significantly in horses immunized with the G3 vaccine. Antigenic differences between genotypes could reduce the vaccine's efficacy, requiring the development of a new vaccine.

[Effect of double-leaf perforator free flap posterolateral calf peroneal artery on reconstruction of oropharyngeal anatomy after ablation of advanced oropharyngeal carcinoma].

OBJECTIVE: To evaluate the effect of using free double- leaf perforator flap posterolateral calf peroneal artery in anatomical reconstruction of the oropharyngeal structure after ablation of advanced oropharyngeal carcinoma. METHODS: Twenty-six patients with oropharyngeal defects after ablation of oropharyngeal malignancies were recruited, including 12 with carcinoma in the tongue base, 5 in the latenral pharyngeal wall and 9 in the soft palate. Between July, 2016 and July, 2018, the patients underwent surgeries for reconstruction of the oropharyngeal defects using flaps. The areas of tissue defects repaired by double-leaf perforator flaps ranged from 40.5 to 72.5 cm2. Reconstruction was performed for oropharyngeal defects in the soft palate, pterygopalate, parapharyngeal, pterygo- mandibular, and tongue base tissues. The patients' outcomes including mouth opening, functions of deglutition, linguistic function, restoration of palatopharyngeal anatomical structure and postoperative survival were evaluated, and their quality of life was assessed using FACT-H&N scale (Chinese Edition). RESULTS: All the 26 patients with transplantation of the free flaps survived. Six months after the operation, the oropharyngeal function and anatomical structure of the patients were basically restored. The questionnaire survey showed that the patients' physical, social/family, emotional and functional conditions, the total score of the core scale, items scores for the head and neck, and the total score of the scale all improved significantly after the operation compared with those before the operation (P < 0.05). CONCLUSIONS: The free peroneal artery bilobate perforator flap in the posterolateral crus, which seldom has anatomical variations of the blood vessels, allows flexible design and contains rich tissue volume to facilitate defect repair with different approaches and ranges. The application of this flap, which is an ideal perforator flap for reconstruction of the oropharyngeal structure and function, can improve the quality of life of patients following operations for advanced oropharyngeal cancer.

[The clinical application of free skin flap transplantation in the one-stage repair and reconstruction after total glossectomy].

Objective:To investigate the clinical application of free skin flap in the one-stage repair and reconstruction after total glossectomy in patients with advanced tongue cancer. Method:Twenty-eight patients who underwent total glossectomy for advanced tongue cancer and treated with the one-stage repair and reconstruction with free skin flap ranged from January 2008 to July 2018 were recruited in this study. Among them, there were 12 cases of squamous cell carcinoma, 8 cases of adenocarcinoma, and 8 cases of adenoid cystic carcinoma. The free radical forearm flap and perforator flap of posterolateral peroneal calf peroneal artery were used in 16 and 12 cases, respectively. All patients were treated with outpatient functional rehabilitation sequence and postoperative radiotherapy within 6 months, and were followed up regularly for 1, 3 and 5 years to understand their living conditions, and Washington University students' quality questionnaire 4 was used to investigate the functional factors of the healthy patients in different periods of time after surgery. Result:The survival rate of the free skin flap was 94%. The radical forearm flap was immediately changed to perforator flap posterolateral peroneal calf peroneal artery in 2 cases due to the necrosis of the artery. The hospitalization time of the patients was 10-14 days, with an average of 12.5 days. The wounds inside and outside of the mouth were healed by first intention at the time of discharge. All nasogastric tube and tracheal tube were removed safely within 45 days after the surgery and the functions of swallowing, breathing, language and chewing were gradually restored. According to the questionnaire survey, patients' attention to quality of life gradually shifted from function to feeling. With the direct calculation method, the 1-,3-, and 5-year survival rate was 96.40%, 64.71%, 55.60%, respectively, while tumor-free survival rate was 85.70%, 58.82%, 55.60%, respectively. Conclusion:The comprehensive treatment based on free tissue flap repair and reconstruction of tissue defects can significantly improve the radical cure rate of patients with advanced tongue cancer, and can effectively restore the functions of swallowing, breathing, language, chewing and so on. It is a kind of treatment method worthy of promotion.

The Presence of Rabies Virus-Neutralizing Antibody in Wild Boars (Sus scrofa), a Non-Target Bait Vaccine Animal in Korea.

Oral vaccination with bait is an effective method to prevent rabies in wildlife, but non-target wild animals may also ingest the bait vaccine. In Korea, the target animal of the rabies bait vaccine is the raccoon dog (Nyctereutes procyonoides). Bait vaccines have been distributed in Korea for 20 years; although wild raccoon dogs have been tested for antibodies, rabies antibodies have never been investigated in non-target wild animals. Therefore, this study investigated rabies antibody formation in wild boars (Sus scrofa), which is likely the main competitor for the bait vaccine in Korea. In bait areas, 20 of 109 wild boars (18.3%) were seropositive, and 39 of 470 wild boars (8.3%) in non-bait areas were also seropositive. These results provide insights regarding bait uptake or vaccination in non-target wild boars.

Immunogenicity of a new, inactivated canine adenovirus type 2 vaccine for dogs.

PURPOSE: We constructed a new canine adenovirus type 2 (CAV-2) vaccine candidate using the recently isolated Korean CAV-2 strain; we termed the vaccine APQA1701-40P and evaluated its safety and immunogenicity in dogs. MATERIALS AND METHODS: To generate the anti-CAV-2 vaccine, APQA1701 was passaged 40 times in MDCK cells growing in medium containing 5 mM urea and the virus was inactivated using 0.05% (volume per volume) formaldehyde. Two vaccines were prepared by blending inactivated APQA1701-40P with two different adjuvants; both were intramuscularly injected (twice) into guinea pigs. The safety and immunogenicity of the Cabopol-adjuvanted vaccine were evaluated in seronegative dogs. The humoral responses elicited were measured using an indirect enzyme-linked immunosorbent assay (I-ELISA), and via a virus neutralization assay (VNA). RESULTS: The new, inactivated CAV-2 vaccine strain, APQA1701-40P, lacked six amino acids of the E1b-19K protein. In guinea pigs, the Cabopol-adjuvanted vaccine afforded a slightly higher VNA titer and I-ELISA absorbance than an IMS gel-adjuvanted vaccine 4 weeks post-vaccination (p>0.05). Dogs inoculated with the former vaccine developed a significantly higher immune titer than non-vaccinated dogs. CONCLUSION: The Cabopol-adjuvanted, inactivated CAV-2 vaccine was safe and induced a high VNA titer in dogs.

Rabies immune status of raccoon dogs residing in areas where rabies bait vaccine has been distributed.

Since 2000, large amounts of rabies bait vaccine have been distributed in two provinces where raccoon dog-mediated rabies has occurred. A total of 146 raccoon dogs were caught in Gangwon and Gyeonggi Provinces from January 2017 to June 2018, and raccoon dog blood samples were collected. Of the 146 raccoon dogs, 13.7% (20/146) had rabies antibodies. In Gyeonggi and Gangwon provinces, the rate of rabies antibody was 8.5% (5/59) and 17.2% (15/87), respectively. Considering these results, it would be desirable to improve the distribution method or use a new bait vaccine to prevent animal rabies in South Korea.

Strategies to maintain Korea's animal rabies non-occurrence status.

Endemic animal rabies causes >99% of all human rabies cases; elimination of animal rabies reduces the rate of human infections. The most recent animal rabies cases in the Gangwon and Gyeonggi provinces of Korea occurred in November 2012 and February 2013, respectively. Here we explore ways to ensure that Korea remains animal rabies non-occurrence. The government must prevent rabies recurrence by vaccinating dogs, distributing bait vaccine in regions with a high rabies risk, performing laboratory-based surveillance, preventing the flow of rabies-suspect animals from neighboring countries, and enhancing border quarantine. As has already been shown in several developed countries, careful and ongoing rabies control will allow Korea to remain animal rabies-free.

Serosurvey of rabies virus, canine distemper virus, parvovirus, and influenza virus in military working dogs in Korea.

Rabies virus (RABV), canine distemper virus (CDV), canine parvovirus type-2 (CPV-2), and canine influenza A virus (CIV) are important contagious pathogens in canine populations. To assess post-vaccination immunity against RABV, CDV and CPV-2, and serological evidence of exposure to influenza A virus in military working dogs (MWDs) in Korea, we tested blood samples of 78 MWDs by fluorescent antibody virus neutralization (FAVN) for RABV, and by commercially available enzyme-linked immunosorbent assay (ELISA) for CDV, CPV-2, and CIV. Korean MWDs had high antibody-positive rates against RABV (97.4%, ≥0.5 IU/ml), CDV (94.8%), and CPV (100%). All dogs tested seronegative (0/78; 0%) for influenza A virus. Two 1-year-old dogs stationed in known rabies outbreak areas (Gangwon and Gyeonggi) exhibited VNA titers below the protective level (0.06 and 0.29 IU/ml, respectively). The breed and sex of MWDs were not significantly associated with antibody titers for RABV, CDV, or CPV; however, age was significantly associated with CPV antibody titers, while region of residence was associated with CDV antibody titer. Taken together, the data presented here provide important insights necessary for post-vaccination management and control of infectious diseases in MWDs.

Efficacy of inactivated variant porcine epidemic diarrhea virus vaccines in growing pigs.

PURPOSE: The first aim of this study was to develop a novel inactivated porcine epidemic diarrhea virus (PEDV) vaccine using the recently isolated Korean PEDV QIAP1401 strain and to evaluate its protective efficacy in growing pigs. The second was to determine the optimum adjuvant formulation of the inactivated PEDV vaccine that induces protection against viral challenge. MATERIALS AND METHODS: To generate high titers of infectious PEDV, the QIAP1401 isolate was passaged in Vero cells. The experimental vaccines were prepared from a binary ethyleneimine-inactivated QIAP1401 strain passaged sequentially 70 times (QIAP1401-p70), formulated with four commercial adjuvants, and administered twice intramuscularly to growing pigs. Challenge studies using a virulent homologous strain of PEDV QIAP1401-p11, which was passaged 11 times after isolation, were performed to assess protection against disease progression and viral shedding during the 15-day observation period. The vaccine-induced antibody responses were measured in serum samples collected at predetermined time points by indirect enzyme-linked immunosorbent assay and virus neutralization test. RESULTS: The QIAP1401-p70 strain had 42 amino acid (aa) mutations, including a 25 aa deletion, and was selected as the inactivated PEDV vaccine candidate. Although none of the pigs that received the experimental vaccines were completely protected against subsequent viral challenge, they exhibited a significantly higher immune response than did non-vaccinated control pigs. Among the vaccine groups, the highest antibody responses were observed in the pigs that received an oil-based multiphasic water/oil/water (W/O/W) emulsion adjuvanted vaccine, which delayed the onset of clinical symptoms and viral shedding. CONCLUSION: A novel inactivated PEDV vaccine formulated with a W/O/W emulsion adjuvant was both immunogenic and protective against viral challenge.

Isolation and characterization of a new porcine epidemic diarrhea virus variant that occurred in Korea in 2014.

Outbreaks of porcine epidemic diarrhea (PED) have resulted in significant economic losses in the swine industry, and another PED outbreak occurred in 2014 in Korea. Isolating and culturing PED virus (PEDV) allow investigations into its pathogenesis and the development of vaccines and diagnostic assays. In this study, we successfully isolated two PEDV isolates (QIAP1401 and QIAP1402) from naturally infected piglets at Jeju-do, Korea. Viral propagation was confirmed in Vero cells based on cytopathic effect, immunofluorescence assay, reverse transcription-polymerase chain reaction, and electron microscopic analyses. The QIAP401 isolate propagated well in Vero cells for 70 passages, with titers of 106.5 to 107.0 50% tissue culture infectious dose/mL, which increased gradually with passaging. The nucleotide and amino acid sequences of the QIAP1401 isolate were determined and compared with those of other PEDV isolates. The QIAP1401 isolate was determined to be closely related to the USA/Minnesota271/2014 strain (> 99.9% nucleotide similarity) that was isolated in the USA in 2014. Phylogenetic analysis based on several PEDV genes suggested that a new PEDV variant is circulating in the Korean swine industry, with 93.08% similarity to the SM98 strain isolated in 1998. In addition, the QIAP1401 strain showed strong virulence in 3-day-old piglets and 11-week-old growing pigs.