Case Report: Management of an Uncommon Crotaline Snakebite (Ovophis makazayazaya)

Ovophis makazayazaya bite is an uncommon cause of snakebite that humans may sustain as a result of the continuous overexploitation of forest habitats and excessive development in Taiwan. Although the Taiwanese government has produced four antivenoms against medically important snakebite accidents, O. makazayazaya is not among the snakes for which an antivenom has been produced. A case of O. makazayazaya snakebite on a patient's right foot, which later swelled into the hip, is reported. In vitro studies have reported that monovalent antivenoms for Gloydius brevicaudus and Trimeresurus albolabris, and polyvalent antivenom for Calloselasma rhodostoma, Daboia siamensis, and T. albolabris show reactivity toward Ovophis venoms. However, these antivenoms are unavailable in Taiwan. Thus, bivalent antivenom for Trimeresurus stejnegeri stejnegeri and Protobothrops mucrosquamatus was used, assuming similar immunoreactivity and a possible para-specific effect of green pit viper antivenom against this Ovophis venom. A favorable outcome was observed, without significant extension in prothrombin time and activated partial thromboplastin time. In addition, no systemic bleeding occurred. Nonetheless, further venom and antivenom evaluations should ascertain the efficacy of this para-specific antivenoms against this crotaline snakebite.