Effect of zinc and vitamin A supplementation on antibody responses to a pneumococcal conjugate vaccine in HIV-positive injection drug users: A randomized trial

HIV-infected individuals have impaired immune responses to vaccines and high rates of pneumococcal disease. The effect of vitamin A and zinc supplementation on the immunogenicity of a 7-valent pneumococcal CRM-197 conjugate vaccine (PC-7) was evaluated in 118 HIV+ injection drug users. Subjects were randomized to oral 400,000 IU vitamin A, 300 mg zinc, vitamin A + zinc, or placebo, then immunized. Geometric mean titer increased 1.3–3.3-fold for all pneumococcal serotypes. PC-7 elicited an immune response in HIV-infected adults but neither vitamin A nor zinc altered the immunogenicity of the evaluated vaccines.