Clinical characteristics of stonefish “Oni‐daruma‐okoze” envenomation in Japan

Abstract

Aim: Stonefish, known in Japan as "Oni-daruma-okoze" (Synanceia verrucosa Block et Schneider), inhabit the waters surrounding the Okinawa/Amami districts. By far, habubites have been limited to these areas mainly due to climatic conditions. Due to changes promoted by global warming and increasing tourism, concerns regarding the potential for stonefish envenomation as well as jellyfish stings on the main island of Japan are increasing. However, few studies of stonefish envenomation have been reported in Japan. The current study aimed to comprehensively examine for the first time the clinical characteristics of stonefish envenomation in Japan. Methods: We administered retrospective questionnaire surveys between January 2013 and December 2017 to determine patient characteristics, treatment, and clinical outcomes of stonefish envenomation. We compared patient characteristics between tourists and non-tourists. Results: Over the 5-year study period, 15 patients were identified from four hospitals. More than 70% of stonefish envenomation cases occurred in the northern part of Okinawa Main Island. All patients recovered well, including four patients with severe stonefish envenomation. In two severe cases, the length of hospitalization was more than 1 week (8-9 days). Antivenom was not given. There were no significant differences between tourists and non-tourists with regard to baseline characteristics. Conclusions: During a 5-year period, 15 cases of stonefish envenomation occurred in Japan. The patients recovered well without treatment with antivenom.

Marine Envenomation in Okinawa: Overview and Treatment Concept

“…In Okinawa, 26% of reported envenomations resulted in severe symptoms. 50 Fortunately, deaths from stonefish are rare in Okinawa, with the most recent reported deaths occurring in 2010 and 1983. 51 Clinical treatment typically involves initial first aid and local wound care, including spine removal if necessary.…”

The Geographic Distribution, Venom Components, Pathology and Treatments of Stonefish (Synanceia spp.) Venom

“…Statistics from independent retrospective clinical studies of stonefish stings from hospitals in the Indo-Pacific region showed that most envenomations occurred in young adult males with occupational or recreational exposure to stonefish habitat [ 4 , 5 , 6 , 7 ]. Stonefish were the second most common fish involved in human envenomations in Hong Kong [ 5 ] and were responsible for one-third of all fish envenomations in Australia in 2008 [ 7 ].…”

“…A recent report by the Australian Institute of Health and Welfare stated that of all hospitalizations due to injury from contact with venomous marine plants and animals from 2017–2018, 81% were caused by stinging fish, where 30 out of 320 cases (9.3%) were due to stonefish envenomation [ 8 ]. Additionally, stonefish have been responsible for a high number of stings in Singapore [ 9 , 10 ], and there are concerns that the number of stings will grow in Japan due to warmer ocean temperatures and increasing tourism [ 6 ]. These studies also report that victims usually sought medical assistance within 2 h of being stung due to intense pain [ 4 , 6 ].…”

“…Additionally, stonefish have been responsible for a high number of stings in Singapore [ 9 , 10 ], and there are concerns that the number of stings will grow in Japan due to warmer ocean temperatures and increasing tourism [ 6 ]. These studies also report that victims usually sought medical assistance within 2 h of being stung due to intense pain [ 4 , 6 ]. The majority of the cases were regarded as mild envenomation, with average hospital stays ranging from hours [ 4 ] to days [ 11 ].…”

“…The majority of the cases were regarded as mild envenomation, with average hospital stays ranging from hours [ 4 ] to days [ 11 ]. In more severe cases, hospitalizations can last for over a week [ 6 ], and surgical interventions may be necessary in some instances [ 4 , 9 , 11 ].…”