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Importance: The World Health Organization has called for eliminating cervical cancer as a public health problem. Accurate and up-to-date estimates of population-based cervical cancer incidence are essential for monitoring progress toward elimination and informing local cancer control strategies, but these estimates are lacking for the US-Affiliated Pacific Islands (USAPI). Objective: To calculate age-standardized incidence rates for cervical cancer in the 6 USAPI and compare these rates with rates in the US (50 states and the District of Columbia). Design, Setting, and Participants: This cross-sectional study used population-based data from the Pacific Regional Central Cancer Registry for women aged 20 years or older who were diagnosed with invasive cervical cancer from January 1, 2007, to December 31, 2020. The registry comprises data on all cervical cancers from the USAPI, which include 3 US territories (American Samoa, Commonwealth of the Northern Mariana Islands, and Guam) and 3 freely associated states (Federated States of Micronesia [FSM], Republic of the Marshall Islands [RMI], and Republic of Palau). Data were analyzed from July 10, 2023, to November 28, 2023. Main Outcomes and Measures: The main outcome was age-standardized cervical cancer incidence rates, stratified by age, stage, and histologic code for the USAPI using population estimates from 3 different sources (US Census Bureau International Database, United Nations Population Division, and Pacific Data Hub). Rate ratios were calculated to compare incidence rates between the USAPI and the US. Results: From 2007 to 2020, 409 cases of cervical cancer were diagnosed in the USAPI (median age at diagnosis, 46.0 years [25th-75th percentile, 39.0-55.0 years]), with an age-standardized incidence rate ranging from 21.7 (95% CI, 19.6-23.9) to 22.1 (95% CI, 20.0-24.4) per 100 000 women, depending on the population estimate. Incidence rates were highest in RMI, ranging from 58.1 (95% CI, 48.0-69.7) to 83.4 (95% CI, 68.3-101.0) per 100 000 women, followed by FSM, ranging from 28.7 (95% CI, 23.4-34.9) to 29.8 (95% CI, 24.3-36.3) per 100 000 women. Compared with the US, incidence rates were highest in RMI (rate ratio, 5.7 [95% CI, 4.7-6.8] to 8.2 [95% CI, 6.7-9.9]) and FSM (rate ratio; 2.8; 95% CI, 2.3-3.4). Of all cases in the USAPI, 213 (68.2%) were diagnosed at a late stage. Conclusions and Relevance: In this cross-sectional study, cervical cancer remained a major public health issue in some USAPI, with RMI reporting the highest incidence rates. The findings suggest that improvements in human papillomavirus vaccination and cancer screening coverage through efforts tailored to the unique geographic, sociocultural, economic, and health care landscape of the USAPI may reduce the burden of cervical cancer.

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BACKGROUND: Breast cancer is the most common cancer diagnosed among women globally and in the United States (US); however, its incidence in the six US-Affiliated Pacific Islands (USAPI) remains less characterized. METHODS: We analyzed data from a population-based cancer registry using different population estimates to calculate incidence rates for breast cancer among women aged >20 years in the USAPI. Rate ratios and 95 % confidence intervals (CI) were calculated to compare incidence rates between the USAPI and the US (50 states and the District of Columbia). RESULTS: From 2007-2020, 1118 new cases of breast cancer were diagnosed in the USAPI, with 66.3 % (n = 741) of cases reported in Guam. Age-standardized incidence rates ranged from 66.4 to 68.7 per 100,000 women in USAPI and 101.1-110.5 per 100,000 women in Guam. Compared to the US, incidence rates were lower in USAPI, with rate ratios ranging from 0.38 (95 % CI: 0.36, 0.40) to 0.39 (95 % CI: 0.37, 0.42). The proportion of late-stage cancer was significantly higher in the USAPI (48.7 %) than in the US (34.0 %), particularly in the Federated States of Micronesia (78.7 %) and Palau (73.1 %). CONCLUSIONS: Breast cancer incidence rates were lower in the USAPI than in the US; however, late-stage diagnoses were disproportionately higher. Low incidence and late-stage cancers may signal challenges in screening, cancer surveillance, and health care access and resources. Expanding access to timely breast cancer screening, diagnosis, and treatment could reduce the proportion of late-stage cancers and improve survival in the USAPI.

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Porcine circovirus (PCV) 2d is a common genotype in South Korea, and the cross-protective ability of PCV2a-based vaccines has been reported recently. In this study, a PCV2d vaccine candidate was selected, and its protective efficacy against the PCV2d isolate was evaluated. From 2016 to 2020, 234 PCV2d isolates were phylogenetically analyzed using open reading frame 2 (ORF2) sequences and classified into four subgroups: PCV2d-1, PCV2d-2, PCV2d-3, and PCV2d-4. Except for PCV2d-4, which consisted of ungrouped isolates, the three subgroups showed distinct differences at amino acid positions 53 and 169 in the ORF2. The detection rates of PCV2d-1, PCV2d-2, and PCV2d-3 were 36.5, 37.4, and 3.7%, respectively, and representative isolates were selected from each subgroup (QIA244, QIA126, and QIA169, respectively). In the neutralization assay, QIA244 showed the lowest neutralization efficiency among the three PCV2a-based vaccines, whereas the virus-like particles of QIA244 (rQIA244) provided broader protection against the three genotypes than did those of QIA126 and rQIA169. To further evaluate rQIA244 in pigs, the experimental groups were divided into rQIA244-vaccine (2dVac), commercial PCV2a-vaccine (2aVac), and no-vaccination (noVac) groups. The 2dVac effectively reduced the copy number of PCV2d in blood and tissues, as well as in tissue lesions, compared to the effect of 2aVac. Collectively, 2dVac provided by QIA244 ORF2 successfully demonstrated protective efficacy against the currently prevalent PCV2d in vitro neutralization and in vivo assays.

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This study aimed to evaluate the efficacy of a virus-like particle (VLP) vaccine containing the open reading frame 2 of porcine circovirus type 2d (PCV2d) in a farm environment where natural infections associated with porcine circovirus-associated disease are endemic. The vaccine trial was conducted on three farms (H, M, and Y) with a history of infections including porcine reproductive and respiratory syndrome virus (PRRSV), PCV, Mycoplasma, and E. coli. Farm H, as well as farms M and Y, experienced natural PCV2 infection between 4 and 8 weeks post-vaccination (wpv), and 8 and 12 wpv, respectively. Viremia levels of all farms were significantly (p < 0.05) lower in vaccinated piglets than the control group after natural infection. In all farms, serum immunoglobulin G levels peaked at 8 wpv in the vaccinated groups, surpassing those in the control groups. Furthermore, neutralizing antibody titers were significantly (p < 0.05) higher in the vaccinated groups than the control groups in farms H and Y (0-8 wpv). However, there were no significant differences between the vaccinated and control group in neutralizing antibody titers of farm M (0-20 wpv). In terms of body weight, vaccinated piglets from all three farms showed significantly increased average weights at 12 wpv compared to the control groups. In conclusion, our study revealed noteworthy differences in viremia and body weight gain between vaccinated and control animals on three farms. As a result, this field trial of PCV2d VLP vaccine was successful in protecting piglets from natural PCV2 infection.

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OBJECTIVE/HYPOTHESIS: Oral cancers in the US-affiliated Pacific Islands are poorly described despite disproportionately higher incidences in certain jurisdictions. This study attempts to better characterize the incidence, staging, and management of oral cancers in this region. STUDY DESIGN: Retrospective Epidemiological Study. METHODS: A retrospective review was conducted across the US-affiliated Pacific Islands between 2007 and 2019. Patient data were obtained for individuals with primary head and neck cancers from the Pacific Regional Central Cancer Registry database. All cohorts were age-adjusted to the 2000 US Standard Population. Further analysis was performed on oral cavity cancers due to their clear predominance within the sample. RESULTS: A total of 585 patients with primary head and neck cancers were included. The average age was 54.5 ± 12.9 years, and most patients were male (76.8%). Oral cancer subsite analysis revealed the proportional incidence of buccal mucosa was higher in 5 of 9 jurisdictions when compared with the United States (p < 0.001). Tongue and lip cancers were not found to have significantly higher incidence proportions. Patients in the Pacific Islander group were less likely to be detected at earlier stages for cancers of the cheek and other mouth (p < 0.001), tongue (p < 0.001), and lips (p < 0.001) compared with the United States. CONCLUSIONS: Many Pacific Island populations are burdened with higher incidences of oral cancer with later staging. Further investigation is recommended to evaluate oral cancer-related outcomes and mortality in this region. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:1899-1905, 2023.

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(1) Background: Ultrasound (US) elastography is an imaging technology that reveals tissue stiffness. This study aimed to investigate whether fibrotic focus (FF) affects elastographic findings in breast cancer, and to evaluate the clinical significance of US elastography and FF in breast cancer. (2) Methods: In this study, 151 patients with breast cancer who underwent surgery were included. Strain elastography was performed and an elasticity scoring system was used to assess the findings. The elasticity scores were classified as negative, equivocal, or positive. FF was evaluated in the surgical specimens. Medical records were reviewed for all patients. (3) Results: Elastographic findings were equivocal in 30 patients (19.9%) and positive in 121 patients (80.1%). FF was present in 68 patients (46.9%). There was no correlation between elastographic findings and FF. Older age, larger tumor size, lymph node metastasis, and higher tumor stage were associated with positive elastographic results. FF showed a positive correlation with age, postmenopausal status, tumor size, lymphovascular invasion, lymph node metastasis, tumor stage, and intratumoral and peritumoral inflammation. (4) Conclusions: Our study showed that positive elastographic results and FF were associated with poor prognostic factors for breast cancer. FF did not affect the elastographic findings of this study.

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For the development of an optimized Egyptian H9N2 vaccine candidate virus for poultry, various recombinant Egyptian H9N2 viruses generated by a PR8-based reverse genetics system were compared in terms of their productivity and biosafety since Egyptian H9N2 avian influenza viruses already possess mammalian pathogenicity-related mutations in the hemagglutinin (HA), neuraminidase (NA), and PB2 genes. The Egyptian HA and NA genes were more compatible with PR8 than with H9N2 AIV (01310) internal genes, and the 01310-derived recombinant H9N2 strains acquired the L226Q reverse mutation in HA after passages in eggs. Additionally, the introduction of a strong promoter at the 3'-ends of PB2 and PB1 genes induced an additional mutation of P221S. When recombinant Egyptian H9N2 viruses with intact or reverse mutated HA (L226Q and P221S) and NA (prototypic 2SBS) were compared, the virus with HA and NA mutations had high productivity in ECES but was lower in antigenicity when used as an inactivated vaccine due to its high binding affinity into non-specific inhibitors in eggs. Finally, we substituted the PB2 gene of PR8 with 01310 to remove the replication ability in mammalian hosts and successfully generated the best recombinant vaccine candidate in terms of immunogenicity, antigenicity, and biosafety.

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CD73 is a lymphocyte differentiation antigen and highly expressed in many human solid tumors. CD73 is known to be associated with tumor progression, but its role in human breast cancer is still under investigation. The aims of this study were to evaluate the expression of CD73 in human breast cancer and to analyze its prognostic significance in breast cancer. A total of 198 patients who underwent surgery for the treatment of primary breast cancer were enrolled. Tissue microarrays (TMA) were constructed with breast cancer tissues and immunohistochemical staining for CD73 was performed on TMA tissue sections. The clinicopathologic characteristics were evaluated from the patient's medical records and pathologic reports. The average age of the patients was 51.7 ± 10.7. Positive expression rate of CD73 for all breast cancer was 25.4%. Positive rate of CD73 expression in invasive breast cancer was 30.9%, which was significantly higher than that of 5.4% of ductal carcinoma in situ. CD73 expression was significantly associated with higher T-stage, node metastasis, positive progesterone receptor status and presence of intratumoral inflammation. There was no significant association between molecular subtypes and CD73 expression. The disease-free survival (DFS) and overall survival (OS) rate at 5 years were 90.1% and 96.6%, respectively. There was no difference in DFS and OS according to CD73 expression. In conclusion, this study showed that CD73 expression is associated with tumor progression and inflammation in breast cancer. Our results suggest that CD73 has a potential as a prognostic marker and a therapeutic target of breast cancer.

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As PCV2d infection has been continuously reported in swine farms in which pigs were vaccinated with PCV2a- or 2d-based vaccines, we attempted to develop a novel vaccine using a PCV2d-based capsid to enhance its protective efficacy. In this study, recombinant virus-like particles (VLPs) of rPCV2a, rPCV2b and rPCV2d were synthesized from the capsid proteins of PCV2a, PCV2b and PCV2d field isolates, respectively. A cross-neutralization assay between the VLPs induced antisera and the field isolates demonstrated the broad cross-neutralizing activities of the rPCV2d-induced antisera. Then, the protective efficacy of rPCV2d as a vaccine candidate was investigated in commercial pigs by rPCV2d vaccination and a single- or dual-challenge infection using a PCV2d strain and a type 1 PRRSV strain. High levels of anti-PCV2d IgG and neutralizing antibodies were induced 3 weeks after vaccination. After the challenge infection, the average ADWG values of the vaccinated group were higher than those of the unvaccinated group. None or a significantly low amount of (p < 0.05) reduced PCV2 genomic DNA was found in the blood, saliva and tissues of the vaccinated pigs, when compared to the unvaccinated group. Moreover, macroscopic and microscopic lesions in the tissues were significantly (p < 0.05) reduced in the vaccinated groups. This study therefore suggests that rPCV2d may be highly useful for the control of diverse field genotypes.

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Triptolide is a diterpenoid epoxide that is endogenously produced by the thunder god vine, Tripterygium wilfordii Hook F. Triptolide has demonstrated a variety of biological activities, including anticancer activities, in previous studies. Invasion and metastasis are the leading causes of mortality for patients with breast cancer, and the increased expression of matrix metalloproteinase-9 (MMP-9) has been shown to be associated with breast cancer invasion. Therefore, the aim of the present study was to investigate the effect of triptolide on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced cell invasion and MMP-9 expression in breast cancer cells. The expression of signal molecules was examined by western blotting, zymography and quantitative polymerase chain reaction; an electrophoretic mobility gel shift assay was also used, and cell invasiveness was measured by an in vitro Matrigel invasion assay. The MCF-7 human breast cancer cell line was treated with triptolide at the highest concentrations at which no marked cytotoxicity was evident. The results demonstrated that triptolide decreased the expression of MMP-9 through inhibition of the TPA-induced phosphorylation of extracellular signal-regulated kinase (ERK) and the downregulation of nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) activity. In addition, a Transwell assay revealed that triptolide reduced the ability of MCF-7 cells to invade Matrigel. These data demonstrate that the anti-invasive effect of triptolide is associated with the inhibition of ERK signaling and NF-κB and AP-1 activation, and suggest that triptolide may be a promising drug for breast cancer.

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Background: The costs of cancer registration have previously been estimated for registries in the continental United States and many international registries; however, to date, there has been no economic assessment of population-based registries in the US-Affiliated Pacific Islands. This study estimates the costs and factors affecting the operations of US-Affiliated Pacific Island population-based cancer registries. Methods: The web-based International Registry Costing Tool1 was used to collect costs, resources used, cancer cases processed, and other registry characteristics from the Pacific Regional Central Cancer Registry (PRCCR), Federated States of Micronesia National Cancer Registry, and nine satellite jurisdictional registries within the US Pacific Islands. The registries provided data on costs for June 30, 2016-June 29, 2017, and cases processed during 2014. Results: Local host institutions provided a vital source of support for US-Affiliated Pacific Islands registries, covering substantial fixed costs, such as management and overhead. The cost per cancer case processed had an almost tenfold variation across registries, with the average total cost per case of about $1,413. The average cost per inhabitant in the US-Affiliated Pacific Islands was about $1.77 per person. Discussion: The challenges of collecting data from dispersed populations spread across multiple islands of the US-Affiliated Pacific Islands are likely leading factors driving the magnitude of the registries' cost per case. The economic information from this study provides a valuable source of activity-based cost data that can both help guide cancer control initiatives and help registries improve operations and efficiency.

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Inexpensive near-infrared microscopy (NIRM) was developed as a convenient technique to detect the medulla loss of scalp hair while reducing analytical time with easy sample preparation, leading to a field screening tool for breast cancer. NIRM has been evaluated as an alternative to synchrotron-based nanoscopy and to the relatively expensive method of conventional infrared microscopy to determine the degree and pattern of medulla loss of scalp hairs of patients with breast cancer and benign diseases, as well as normal healthy individuals. NIR imaging showed a strong, scattering-based hyperintense contrast of the medulla compared to the fully attenuated cortex in medullated healthy hair. Complete medulla loss (CML) per hair strand was more extensively (60.9 ± 10.2 %) (p < 0.001) detected in the hair of all cancer patients than in the hair of either healthy individuals (less than 3.7 ± 7.5%) or those with benign disease (30.6 ± 5.9 % ), suggesting a potential biomarker for breast cancer diagnosis. The medulla structure was retained mostly in the hair of age-matched healthy individuals, but discontinuous medulla loss was observed concomitantly with less CML in fibroadenoma patients. Potentially, compact NIRM modules can be integrated into a mobile platform as point-of-care technology for breast cancer screening.

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PURPOSE: Peroxisome proliferator-activated receptor γ (PPARγ) is involved in the pathology of numerous diseases including atherosclerosis, diabetes, obesity, and cancer. Matrix metalloproteinases (MMPs) play a significant role in tissue remodeling related to various processes such as morphogenesis, angiogenesis, tissue repair, invasion, and metastasis. We investigated the effects of PPARγ on MMP expression and invasion in breast cancer cells. METHODS: MCF-7 cells were cultured and then cell viability was monitored in an MTT assay. Western blotting, gelatin zymography, real-time polymerase chain reaction, and luciferase assays were performed to investigate the effect of the synthetic PPARγ ligand troglitazone on MMP expression. Transcription factor DNA binding was analyzed by electrophoretic mobility shift assay. A Matrigel invasion assay was used to assess the effects of troglitazone on MCF-7 cells. RESULTS: Troglitazone did not affect MCF-7 cell viability. 12-O-tetradecanoylphorbol-13-acetate (TPA) induced MMP-9 expression and invasion in MCF-7 cell. However, these effects were decreased by troglitazone. TPA increased nuclear factor κB and activator protein-1 DNA binding, while troglitazone inhibited these effects. The selective PPARγ antagonist GW9662 reversed MMP-9 inhibition by troglitazone in TPA-treated MCF-7 cells. CONCLUSION: Troglitazone inhibited nuclear factor κB and activator protein-1-mediated MMP-9 expression and invasion of MCF-7 cells through a PPARγ-dependent mechanism.

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Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia, resulting in considerable economic losses in the swine industry. A few genome sequences of M. hyopneumoniae have been reported to date, implying that additional genome data are needed for further genetic studies. Here, we present the annotated genome sequence of M. hyopneumoniae strain KM014.

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Actinobacillus pleuropneumoniae is a bacterial pathogen causing highly contagious porcine pleuropneumonia. Due to limited information on this species, it is difficult to study the biology of A. pleuropneumoniae at the genome level. Here, we report the fully annotated genome sequence of A. pleuropneumoniae strain KL 16.

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BACKGROUND: Fruits of Morus alba L. (mulberry) have various bioactive compounds such as polyphenols and anthocyanins and used as a herbal medicine. However, the anti-cancer effects and molecular basis have not been elucidated. METHODS: We isolated the cyanidin-3-glucoside in various cultivar of mulberry by acidified-methanol extraction methods. This molecule were compared mass spectroscopic properties by LC-MS/MS and analyzed by 1H and 13C NMR. We examined the anti-cancer effect with molecular mechanisms of the cyanidin-3-glucoside on MDA-MB-453 human breast cancer cells and xenograft animal model. RESULTS: The treatment with the mulberry cyanidin-3-glucoside decreased cell viability in a dose-dependent manner with alteration of apoptotic protein contents, and DNA fragmentation, suggesting that cells undergo apoptosis. Supporting the observations, Treatment with the cyanidin-3-glucoside showed active apoptosis by caspase-3 cleavage and DNA fragmentation through Bcl-2 and Bax pathway. Indeed, cyanidin-3-glucoside inhibits tumor growth in MDA-MB-453 cells-inoculated nude mice. Tumor growth of xenograft nude mouse was significantly reduced compared to the control group by the cyanidin-3-glucoside. CONCLUSION: The data demonstrate that cyanidin-3-glucoside isolated from mulberry induced apoptosis in breast cancer (MDA-MB-453) cells, and therefore, has a potential as an anti-cancer agent. These results show that mulberry cyanidin-3-glucoside inhibit the proliferation and growth in vitro and in vivo model and, indicating the inhibition of tumor progression.

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BACKGROUND: Tumor hypoxia induces the expression of several genes via the hypoxia-inducible transcription factor-1 alpha (HIF-1a). It is associated with the prognosis of several cancers. We studied the immunohistochemical expression of HIF-1a in patients with invasive ductal cancer (IDC) of the breast and the possible correlation with the maximum standardized uptake value of the primary tumor (pSUVmax) as well as other biological parameters. Prognostic significance of pSUVmax and expression of HIF-1a for the prediction of progression-free survival (PFS) was also assessed. MATERIAL AND METHODS: Two-hundred seven female patients with IDC who underwent pretreatment fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) were enrolled. The pSUVmax was compared with clinicopathological parameters including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), axillary lymph node (LN) metastasis, stage and HIF-1a expression. The prognostic value of pSUVmax for PFS was assessed using the Kaplan-Meier method. RESULTS: pSUVmax was significantly higher in patients with HIF-1a expression ≥ 2 compared to patients with HIF-1a expression < 2 (5.2 ± 4.5 vs. 3.7 ± 3.1, p = 0.008). pSUVmax was also significantly higher in higher stage (p < 0.000001), ER-negative tumors (p < 0.0001), PR-negative tumors (p = 0.0011) and positive LN metastasis (p = 0.0013). pSUVmax was significantly higher in patients with progression compared to patients who were disease-free (6.8 ± 4.4 vs. 4.1 ± 3.7, p = 0.0005). A receiver-operating characteristic curve demonstrated a pSUVmax of 6.51 to be the optimal cutoff for predicting PFS (sensitivity: 53.6%, specificity: 86.0%). Patients with high pSUVmax (> 6.5) had significantly shorter PFS compared to patients with low pSUVmax (p < 0.0001). CONCLUSIONS: pSUVmax on pretreatment F-18 FDG PET/ CT reflect expression of HIF-1a and can be used as a good surrogate marker for the prediction of progression in patients with IDC. The amount of FDG uptake is determined by the presence of glucose metabolism and hypoxia in breast cancer cell.

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Nanoscopic synchrotron X-ray imaging was performed on scalp hair samples of patients with breast cancer and healthy individuals to investigate any structural differences as diagnostic tool. Hair strands were divided into 2-3 segments along the strands from root to tip, followed by imaging either in projection or in CT scanning with a monochromatic 6.78-keV X-ray using zone-plate optics with a resolving power of 60 nm. All the examined cancer hairs exhibited medulla loss with cancer stage-dependent pattern; complete loss, discontinuous or trace along the strands. In contrast, medullas were well retained without complete loss in the healthy hair. In the CT-scanned axial images, the cortical spindle compartments had no contrast in the healthy hair, but appeared hypointense in contrast to the surrounding hyperintense cortical membrane complex in the cancer hair. In conclusion, observation of medulla loss and cortical membrane enhancements in the hair strands of breast cancer patients demonstrated structural variations in the cancer hair, providing a new platform for further synchrotron X-ray imaging study of screening breast cancer patients.

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Porcine group C rotaviruses (RVCs) are considered important pathogens due to their economic impact on pig industry and may also cross the host species barrier toward humans. Unlike RVA, however, genetic and phylogenetic data on RVCs from pigs and other host species are scarce. In the present study, full-length ORF sequences of 26 VP7, 9 VP4 and 9 VP6 genes of Korean porcine RVC strains were compared with those of other known RVC strains by phylogenetic analyses and pairwise identity frequency graphs. Applying the established 85% nucleotide identity cut-off value for RVC VP7 classification, the 26 Korean porcine RVC strains belonged to the G1, G3, G6 and G7 genotypes. Although more complete RVC VP4 sequences are warranted before a definitive cut-off value could be determined, a provisional 83% nucleotide cut-off value proposed for RVC VP4 classification resulted in 7 P-genotypes, 5 of which possessed porcine RVC strains. A 90% nucleotide cut-off value for VP6 divided RVC strains into 7 I-genotypes, 5 of which had porcine RVC strains. G/P/I-genotype comparisons suggested the occurrence of rather frequent reassortment events among Korean porcine RVC strains, and strong geographical differences in the distribution of RVC G-genotypes worldwide. Our data indicate that a large genetic diversity exists among porcine RVC strains. For the final genotype determination of each gene segment, more intensified epidemiological studies on animal and human RVC strains throughout the world are needed.

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This study reports the prevalence of duck hepatitis A virus (DHAV) types 1 and 3 on Korean duck farms. By RT-nested PCR assays specific for DHAV-1 or DHAV-3, DHAV-1 was detected in 9 of 157 liver samples (5.7 %) from 2 of 30 farms (6.7 %), and DHAV-3 was positive in 104 of 157 liver samples (66.2 %) from 23 of 30 farms (76.7 %). Dual infections with DHAV-1 and DHAV-3 were detected in 23 of 157 samples (14.6 %) from 5 of 30 farms (16.7 %). The data indicate that DHAV-3 infections are prevalent and that DHAV-1 reemerged in Korea, resulting in dual infections on several farms. Our data will help to establish a vaccination policy against DHAV-1 and DHAV-3 in Korea.

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