HBV serology was considered positive (HBVab) - either acute or chronic active or past cured infection in 29.1% (95%CI: 25.5-34.7) of IDUs and 8.9% (95%CI: 0.5-17.2) in nIDUs -including 18 anti-HBc antibodies-only cases (Table 2). The gene discussed is KRT88P; the disease is infection.