Identification of main biting midge species and detection of arboviruses from those, Korea

Culicoides biting midges are known to transmit several diseases caused by viruses. Bluetongue virus and African house sickness virus are transmitted to ruminants and equids, respectively. It is essential for control and prevention of arboviral diseases to identify the principal vectors in specific countries and regions. We undertook this study to identify main biting midges and to detect the arboviruses from those.

Culicoides biting midges transmitting arboviruses in three cattle farms were collected in Tongyeong city in Gyeongnam province and Gangjin city in Jeongnam province and Goyang city in Gyeonggi province, from May to October, 2010. Adult Culicoides biting midges were collected once a week by using a light trap. The trap was set between 4:00 and 5:00 p.m. and collected the next morning in 9:00. Collected samples were sent to National Veterinary Research and Quarantine Service (NVRQS) and were sorted into species based on the identification keys of Kitaoka (1984) and were stored at -80Ž until virus detection. Samples were pooled based on collection date and species. Arboviruses in Culicoides biting midges were detected by RT-PCR.

A total of 21,297 Culicoides biting mideges were collected. Culicoides punctatus, Culicoides arakawae, Culicoides oxystoma, Culicoides maculatus, Culicoides japonicus were 87.9%, 7.7%, 3.9%, 2.5%, 0.8%, rerspectively. Culicoides punctatus was most frequently collected all three provinces and proved to be the most abundant Culicoides spp. in Korea. Identified midges were used for detecting arboviruses. Akabane virus, Aino virus, Chuzan virus and bovine ephemeral fever virus were detected from only Culicoides punctatus and Culicoides arakawae by RT-PCR