Dengue fever, COVID-19 (SARS-CoV-2), and Antibody-Dependent Enhancement (ADE): A perspective

SARS‐CoV‐2 pandemic and recurrent dengue epidemics in tropical countries have turned into a global health threat. While both virus‐caused infections may only reveal light symptoms, they can also cause severe diseases. Here, we review the possible antibody‐dependent enhancement (ADE) occurrence, known for dengue infections, when there is a second infection with a different virus strain. Consequently, preexisting antibodies do not neutralize infection, but enhance it, possibly by triggering Fcg receptor‐mediated virus uptake. No clinical data exist indicating such mechanism for SARS‐CoV‐2, but previous coronavirus infections or infection of SARS‐CoV‐2 convalescent with different SARS‐CoV‐2 strains could promote ADE, as experimentally shown for antibodies against the MERS‐CoV or SARS‐CoV spike S protein.