Nation-wide surveillance of tick (Acari: Ixodidae) infestations of humans in Singapore

Abstract

Summary: Ticks are an increasingly important threat to public health in Southeast Asia, due to the role of many tick species as parasites of humans and as vectors of zoonotic pathogens. Singapore is a densely populated Southeast Asian nation with a rich tick fauna and a significant mosaic of city and greenspace. However, apart from occasional case reports, the human-biting ticks in Singapore have received little attention from researchers. Based on an ongoing nationwide tick surveillance program beginning in 2018 and literature records (since 2002), we present data from 51 cases of tick infestation in humans in Singapore involving 128 individual ticks of 11 species. The genera Dermacentor, Haemaphysalis, Ixodes, and Amblyomma were all found to bite humans in Singapore. The most common species infesting humans in Singapore was Dermacentor auratus which was responsible for more than half of all infestations. The first records of Haemaphysalis papuana in Singapore are also presented, with 3 cases of human infestation by this tick species. Finally, we highlight the Singapore National Tick Reference Collection (SNTRC) as an invaluable resource for the identification and study of ticks in Singapore.

Keywords

• Otoacariasis
• Zoonosis
• Spillover
• Tick-borne disease
• Haemaphysalis papuana