Number of seasonal exposures to Japanese cedar pollen increases the risk of sensitization: Observational study in Korean adults.

Sensitization to seasonal allergens usually requires repeated exposure to them. However, research on the extent of exposure that increases the risk of sensitization to specific allergens is lacking. Therefore, we investigated the levels of exposure to Japanese cedar pollen that increased the risk of sensitization to it. A cross-sectional study was conducted with 857 college students living in Jeju, South Korea, as it is the only province in Korea where Japanese cedar pollen levels are high. Questionnaires about demographic characteristics were distributed and skin prick tests for allergic sensitization were performed. Sensitization rates of groups divided by residence period were 3.8% (less than 1 year), 1.8% (1-2 years), 8.5% (2-3 years), 10.3% (3-4 years), 14.8% (4-10 years), and 19.1% (over 10 years). Residence period was an influencing factor of sensitization rate to Japanese cedar pollen, and the cut-off value of the residence period that increased the risk of sensitization to Japanese cedar pollen was found to be 25 months. Repeated exposure to seasonal allergens was related to an increased sensitization rate in young adults. Our results suggested that exposure to Japanese cedar pollen for over two seasons could increase the risk in Korean adults.

Clinical Characteristics of Macrolide-Resistant Mycoplasma pneumoniae from Children in Jeju.

Mycoplasma pneumoniae is the major pathogen of community-acquired pneumonia in children. The prevalence of macrolide-resistant M. pneumoniae (MRMP) is important owing to the limited alternative therapies for children. We analyzed 111 M. pneumoniae obtained from 107 children admitted for lower respiratory tract infection at Jeju National University Hospital between 2010 and 2015. Macrolide resistance of M. pneumoniae was searched for using polymerase chain reaction (PCR) and sequencing. Of 107 clinical M. pneumoniae, 11 (10.3%) carried macrolide resistance mutations in the 23S rRNA gene. All macrolide resistance mutations were A2063G transitions. We found an acquired A2063G mutation of M. pneumoniae from a patient during macrolide treatment. Patients' characteristics and clinical severity did not differ between those with MRMP and macrolide-sensitive M. pneumoniae, with the exception of frequent pleural effusion in the MRMP group. The prevalence of MRMP (10.3%) in Jeju Island was relatively lower than those of surrounding countries in East Asia. Previous antimicrobial usage and timing of diagnostic test should be considered when determining of macrolide resistance of M. pneumoniae.

Foodborne outbreak of human brucellosis caused by ingested raw materials of fetal calf on Jeju Island.

Since the first reported case of human brucellosis in 2002 in South Korea, its incidence has been increasing nationally. However, bovine brucellosis has not been present from 2005 to date on Jeju Island. Despite Jeju Island being considered a clean area for bovine brucellosis, we experienced an outbreak of human brucellosis between 2012 and 2013. Herein, we report cases with human brucellosis after ingestion of raw materials of fetal calf at a restaurant. Patients were identified by isolation of the Brucella abortus in their blood and joint tissue. Because all patients developed zoonosis by a faulty folk remedy, we emphasize the importance of educational programs to increase the awareness of zoonosis, and the need for active surveillance and detection of illegal distribution channels of the infected animal. After the outbreak, we took control of the involved restaurant and its illegal distribution channel, and there have been no further outbreaks.

Differentiation of Streptomyces spp. which cause potato scab disease on the basis of partial rpoB gene sequences.

In a previous study, we found that the phylogenetic analysis of partial rpoB sequences can be used effectively to phylogenetically differentiate Streptomyces spp. [B.J. Kim, C.J. Kim, J. Chun, Y.H. Koh, S.H. Lee, J.W. Hyun, C.Y. Cha, Y.H. Kook, Phylogenetic analysis of the genera Streptomyces and Kitasatospora based on partial RNA polymerase beta-subunit gene (rpoB) sequences, Int. J. Syst. Evol. Microbiol. 54 (2004) 593-598]. In the present study, we analyzed the partial rpoB gene sequences of 19 reference Streptomyces strains associated with potato scab. Furthermore, to empirically confirm the usefulness of rpoB gene analysis for the phylogenetic differentiation of Streptomyces spp., we applied the proposed system to 27 potato scab isolates obtained from the Korean provinces of Jeju-do and Kangwon-do. Phylogenetic relationships among these isolates using the devised rpoB gene-based methods were generally similar to those reported for 16S rRNA gene-based analysis. Isolates from potato scab lesion in Korea were also clearly differentiated into their phylogenetic groups by this method. In addition, the deduced RpoB amino acid sequences were also found to be useful for differentiating these strains. Our data demonstrate that the rpoB gene-based method can be used as a means of complementing other genetic methods such as 16S rRNA gene analysis or DNA-DNA hybridization to phylogenetically differentiate potato scab related Streptomyces spp.