An asymptomatic 35-year-old man comes to the clinic because he was found to be HBsAg positive. Additional tests show: anti-HBc positive, IgM anti-HBc negative, HBeAg negative, anti-HBe positive, ALT 65 IU/L, AST 32 IU/L, HBV DNA 2850 IU/mL.

Among available additional tests, when should testing for antibodies against HDV (anti-HDV) be ordered?