The ECDC Communicable Disease Threats Report (CDTR) is a weekly bulletin for epidemiologists and health professionals on active public health threats. This issue of the ECDC Communicable Disease Threats Report (CDTR) covers the period 28 March – 3 April 2026, and includes updates on SARS-CoV-2 variant classification, Middle East respiratory syndrome coronavirus (MERS-CoV), cholera, HIV, and avian influenza.