We examine the role of Venezuelan forced migration on the propagation of 15 infectious diseases in Colombia. For this purpose, we use rich municipal-monthly panel data. We exploit the fact that municipalities closer to the main migration entry points have a disproportionate exposure to infected migrants when the cumulative migration flows increase. We find that higher refugee inflows are associated with increments in the incidence of vaccine-preventable diseases, such as chickenpox and tuberculosis, as well as sexually transmitted diseases, namely syphilis. However, we find no significant effects of migration on the propagation of vector-borne diseases. Contact with infected migrants upon arrival seems to be the main driving mechanism.