Regarding the source cases of OBHs, i.e. the patients involved in accidents whereserological data were collected, 2.203 (89.4%) were known; the serological marker(HBsAg) tested positive in 15 cases (0.61%); and the presence of hepatitis B coreantibody (anti-HBc), indicating current or past infection, was identified in 188(7.6%) of the patients. This evidence concerns the gene KRT88P and infection.