Table 2.
Cross-neutralization by paraspecific antivenoms against the lethal effect of selected sea snake venoms in mice.
| Venom | TBAV (preincubation) | NKMAV (preincubation) | NPAV (preincubation) | NPAV (challenge-rescue) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ED50 (µL) | ER50 (mg/mL) | P (mg/mL) | ED50 (µL) | ER50 (mg/mL) | P (mg/mL) | ED50 (µL) | ER50 (mg/mL) | P (mg/mL) | ED50 (µL) | ER50 (mg/mL) | P (mg/mL) | |
| Hydrophis schistosus | 141.36 | 0.027 (0.019–0.035) | 0.016 | 89.89 | 0.045 (0.032–0.058) | 0.027 | 100.00 | 0.074 (0.053–0.095) | 0.059 | 70.68 | 0.070 (0.047–0.109) | 0.042 |
| Hydrophis curtus | 200.00 | 0.032 (0.021–0.050) | 0.019 | 89.89 | 0.070 (0.045–0.109) | 0.042 | 125.00 | 0.092 (0.059–0.143) | 0.074 | 70.68 | 0.143 (0.135–0.143) | 0.086 |
| Laticauda laticaudata | - | - | - | - | - | - | 75.00 | 0.075 (0.060–0.090) | 0.045 | - | - | - |
| Laticauda semifasciata | - | - | - | - | - | - | 50.00 | 0.253 (0.173–0.391) | 0.15 | - | - | - |
TBAV: Taiwan bivalent antivenom (for Naja atra and Bungarus multicinctus); NKMAV: Thai Naja kaouthia monovalent antivenom; NPAV: Thai neuro polyvalent antivenom. ED50: median effective dose, defined as the volume of reconstituted antivenom that protects 50% of mice from death; ER50: Effective dose ratio, defined as amount of venom neutralized per mL antivenom at which 50% of envenomed mice survived; P: Potency, defined as amount of venom neutralized per mL antivenom in total (presumably 100% survival conferred) [16]. Parentheses indicate the 95% C.I.; -: not determined. All venom doses used in neutralization study = 2.5 LD50, except in pre-incubation method for NPAV where 5 LD50 of H. schistosus and H. curtus venoms were used. The venom challenge doses (2.5 or 5 LD50) were all higher than the LD100 values of the corresponding venoms (1.2–1.6 LD50).