on of ROS are essential in the first phase of the viral replication, most probably inducing the arrest of the viral DNA polymerases, which is active in the first 1–3 h of viral contamination.117,118 This specific mechanism of action restricts ZnO NPs to an application only at the early stage of infections. However, the same approach with other metals able to induce Fenton or Fenton-like reactions (e.g., Fe, Cu, and Mn) has not be