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The small hive beetle (SHB), Aethina tumida Murray, is a parasite of honey bee colonies and causes the fermentation of honey as well as colony collapse. Outbreaks have been confirmed in Africa, America, Europe as well as Asia, where an outbreak was reported in the Philippines and South Korea in 2014 and 2017, respectively. In South Korea, in September 2016, this honey bee parasite was first identified in apiaries in Miryang, Gyeongnam Province. However, the invasion pathway of SHB has not been identified, and honey bee pathogens harbored by SHB have not been well characterized. Therefore, phylogenetic analysis of SHB with the use of COI gene and detection of fourteen common honey bee pathogens were conducted in this study. The confirmation of the fourteen honey bee pathogens in SHB showed that this beetle carries black queen cell virus and deformed wing virus. Therefore, SHB could have a role in the spread of these viruses. The way of entry of the SHB to South Korea remains undetermined, but the phylogenetic analysis of the COI gene revealed that it was most similar to species found in the USA. There is an urgent need for national-level monitoring and quarantine measures for preventing the spread of SHB infestation in South Korea.

Background: Tick-borne diseases (TBDs) can be fatal to humans as well as to animals causing severe economic losses globally to livestock industries. Many countries conduct regular surveillance of TBDs in livestock. Serological and molecular surveillance of TBDs in livestock and humans was carried out in the Republic of Korea. However, there are not a lot of data on analyses of anaplasmosis in Korean native goats and the correlation with rearing methods and seasons. Methods: In this study, goats in Ulsan city were tested for anaplasmosis by PCR and 16S rRNA sequencing. A total of 452 goat blood samples were collected from 20 farms in 2016. The goat farms in Ulsan city had three different types of rearing methods: conventional, confined, and mixed grazing-confined. Results: Forty-nine of the 452 goats (10.8%) were anaplasmosis positive. Sequence analysis of the PCR products from these 49 goats revealed that 39 of 452 goats (8.6%) were Anaplasma bovis positive, and 10 of 452 goats (2.2%) were infected with Anaplasma capra. The highest outbreaks of anaplasmosis occurred in mixed grazing-confined type of farms (27.1%, 33/122) (χ2 = 60.72, df = 2, p < 0.05), but there was no significant difference in the occurrence of anaplasmosis between spring, summer, and fall seasons. Conclusions: This study was the first detection of A. bovis in Korean native goats and its relationship with rearing methods and seasons. These findings suggested that Korean native goats were highly exposed to Anaplasma spp. during summers when the tick population is the highest and in farms employing mixed grazing-confined rearing methods. [ABSTRACT FROM AUTHOR]

The detection of West Nile virus (WNV) in areas endemic for Japanese encephalitis virus (JEV) is complicated by the extensive serological cross-reactivity between the two viruses. A testing algorithm was developed and employed for the detection of anti-WNV antibody in areas endemic for JEV. Using this differentiation algorithm, a serological survey of poultry (2004 through 2009) and horses (2007 through 2009) was performed. Among 2681 poultry sera, 125 samples were interpreted as being positive for antibodies against JEV, and 14 were suspected to be positive for antibodies against undetermined flaviviruses other than WNV and JEV. Of the 2601 horse sera tested, a total of 1914 (73.6%) were positive to the initial screening test. Of these positive sera, 132 sera (5.1%) had been collected from horses that had been imported from the United States, where WNV is endemic. These horses had WNV vaccination records, and no significant pattern of increasing titer was observed in paired sera tests. Of the remaining 1782 positive sera 1468 sera (56.4%) were also found to contain anti-JEV antibodies, and were interpreted to be JEV-specific antibodies by the differentiation algorithm developed in this study. The remaining 314 horses (12.1%) for which a fourfold difference in neutralizing antibody titer could not be demonstrated, were determined to contain an antibody against an unknown (unidentified or undetermined) flavivirus. No evidence of WNV infections were found during the period of this study.

A novel hemorrhagic metalloprotease, halysase, isolated from the snake venom of Gloydius halys induces apoptosis in endothelial cells. The purified metalloprotease is a monomeric glycoprotein with an isoelectric point of 4.8. Analysis of the cDNA sequence encoding halysase revealed that the enzyme consists of multifunctional domains including a proprotein domain, a protease domain, a disintegrin-like domain and a cysteine-rich domain. The metalloprotease has a DECD sequence in the disintegrin-like domain instead of the typical RGD sequence. Halysase strongly inhibits proliferation of human umbilical vein endothelial cells in a dose-dependent manner as well as adhesion of the cells to extracellular matrix proteins. The enzyme specifically hydrolyzes not only extracellular matrix proteins such as fibronectin, vitronectin, and type IV collagen, but also integrins alpha1beta1 and alpha5beta1. The apoptosis of endothelial cells induced by halysase is closely associated with activation of caspase-3 and decreased level of Bcl-X(L)/Bax. Apohalysase, which lacks metalloprotease activity, is also able to induce the apoptosis. Several lines of experimental evidence suggest that the protease domain and the disintegrin-like domain of halysase cooperatively contribute to the induction of endothelial cell apoptosis.