Four Year Surveillance of the Vector Hard Ticks for SFTS, Ganghwa-do, Republic of Korea

Abstract

The seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus was monitored with a collection trap method every April to November during 2015-2018 and with a flagging method every July and August during 2015-2018 in Ganghwa-do (island) of Incheon Metropolitan City, Republic of Korea. This monitoring was performed in a copse, a short grass field, coniferous forest and broad-leaved forest. A total of 17,457 ticks (8,277 larvae, 4,137 nymphs, 3,389 females, and 1,654 males) of the ixodid ticks comprising 3 species (<i>Haemaphysalis</i> <i>longicornis</i>, <i>H</i>. <i>flava</i>, and <i>Ixodes</i> <i>nipponensis</i>) were collected with collection traps. Of the identified ticks, <i>H</i>. <i>longicornis</i> was the most frequently collected ticks (except larval ticks) (94.26%, 8,653/9,180 ticks (nymphs and adults)), followed by <i>H</i>. <i>flava</i> (5.71%, 524/9,180) and <i>Ix</i>. <i>nipponensis</i> (less than 0.04%, 3/9,180). The ticks collected with collecting traps were pooled and assayed for the presence of SFTS virus with negative results. In addition, for monitoring the prevalence of hard ticks, a total of 7,461 ticks (5,529 larvae, 1,272 nymphs, 469 females, and 191 males) of the ixodid ticks comprising 3 species (<i>H</i>. <i>longicornis</i>, <i>H</i>. <i>flava</i>, and <i>Ix</i>. <i>nipponensis</i>) were collected with flagging method. <i>H</i>. <i>longicornis</i> was the highest collected ticks (except larval ticks) (99.53%, 1,908/1,917 ticks (nymphs and adults)), followed by <i>H</i>. <i>flava</i> (1.15%, 22/1,917).