In the period 2007–2018, the lowest frequency of acute hepatitis B (anti-HBc IgM+) was detected in persons subjected to EPI-HBV (from 0.06/105 in 2007 to 0.05/105 in 2019) and in vaccinated 14-year-olds (up to 0.27/105 in 2007 and 2019). The gene discussed is CD40LG; the disease is hepatitis B virus infection.