| [aggravation of snake bite in france and their treatment]. | vipers at the origin of envenoming: out of the 4 species of vipers found in france, only two can be responsible for severe envenoming: the aspic viper (vipera aspis) and the addetr (vipera berus). clinical grading: since 1992, a grading table published by the institut pasteur in paris helps to assess the severity of the clinical and biological picture. a grade 2 (extensive oedema +/- accompanied by moderate general signs) or notably a grade 3 (giant oedema + severe general signs + biological sig ... | 2003 | 12947747 |