The current epidemiological status of infectious coryza and efficacy of PoulShot Coryza in specific pathogen-free chickens

Infectious coryza (IC) is an infectious disease caused by Avibacterium (Av.) paragallinarum. IC is known to cause economic losses in the poultry industry via decreased egg production in layers. Between 2012 and 2013, Av. paragallinarum was isolated from seven chicken farms by Chungbuk National University. We identified Av. paragallinarum, the causative pathogen of IC by polymerase chain reaction (PCR) and serovar serotype A, by multiplex PCR. Antibiotic sensitivity tests indicated that a few field-isolated strains showed susceptibility to erythromycin, gentamicin, lincomycin, neomycin, oxytetracycline, spectinomycin, and tylosin. A serological survey was conducted to evaluate the number of flocks that were positive for Av. paragallinarum by utilizing a HI test to determine the existence of serovar A. Serological surveys revealed high positivity rates of 86.4% in 2009, 78.9% in 2010, 70.0% in 2011, and 69.6% in 2012. We also challenged specific pathogen-free chickens with isolated domestic strains, ADL121286 and ADL121500, according to the measured efficacy of the commercial IC vaccine, PoulShot Coryza. We confirmed the effectiveness of the vaccine based on relief of clinical signs and a decreased re-isolation rate of ADL121500 strain. Our results indicate IC is currently prevalent in Korea, and that the commercial vaccine is effective at protecting against field strains.

An unusual case of concomitant infection with chicken astrovirus and group A avian rotavirus in broilers with a history of severe clinical signs

A molecular study of intestinal samples from 21 broiler flocks with a history of enteritis revealed that 23.8% and 14.3% were positive for chicken astrovirus (CAstV) and avian rotavirus (ARV), respectively. CAstV and group A ARV were simultaneously detected in only one broiler flock. Birds in this group developed the significant intestinal lesions characterized by frothy contents, paleness, and thin intestinal walls. In this report we present an unusual case of runting stunting syndrome (RSS) with a history of high mortality and growth retardation in broiler chickens. We also make the first identification of CAstV and group A ARV in broiler chickens in Korea.

Evaluation of the Real-Q HCV Quantification Kit / 대한임상미생물학회지

BACKGROUND: Hepatitis C virus (HCV) RNA quantification is necessary for predicting the therapeutic response and assessing treatment results in patients with chronic HCV infection. Recently, real-time PCR technology for HCV RNA quantification displayed good linearity within the dynamic range. Thus, it is gradually replacing branched-DNA (bDNA) and PCR- hybridization assays. In this study, we evaluated the performance of the Real-QTM HCV quantification kit (biosewoom. Inc., Seoul, Korea) developed in Korea. METHODS: We evaluated the HCV quantification kit for detection limit, specificity, linearity, accuracy, and recovery rate of HCV RNA standard material. The results were analyzed for a correlation with those of Cobas Amplicor HCV Monitor 2.0. RESULTS: The HCV quantification kit showed a high recovery rate of HCV RNA standard material of various concentrations and amplication of HCV RNA equally in all genotypes. Hepatitis B virus and human immunodeficiency virus showed no cross-reactivity with HCV. Within-run and between-run coefficients of variation (CV) were 9.52~15.84% and 9.40~17.53%, respectively. Between-day coefficients of variation were 11.62~18.04%, and detection limit was 44 IU/mL. It showed a good correlation with Cobas Amplicor HCV Monitor 2.0 (R2=0.8954). CONCLUSION: The Real-Q HCV quantification kit showed a good specificity, sensitivity, linearity, and accuracy; therefore, we propose that it is fully adequate for monitoring antiviral therapy in patients with chronic HCV infection.