The Enforcement Directorate, the central probe agency in the National Herald case, has issued fresh summons to Congress leader Rahul Gandhi. According to sources, the ED has called for his appearance on June 13-14. The Congress said on Thursday that party president Sonia Gandhi is infected with the coronavirus, though she will appear before the Enforcement Directorate (ED) on June 8 in connection with the probe into money laundering charges related to the National Herald case.