As a public health emergency of international concern, the novel coronavirus disease (COVID-19) pandemic has drawn worldwide attention and a global response. All countries and areas have initiated measures to contain and mitigate transmission and reduce the impact of the outbreak on health-care systems, including shifting health-care resources to the COVID-19 response. During an epidemic, even a temporary interruption of basic health-care delivery such as routine immunization services may lead to secondary health crises such as measles outbreaks during or after the recovery phase, amplifying the economic damage of the epidemic and exacerbating morbidity and mortality. Immunization delivery strategies may need to be adapted and should be conducted under safe conditions, without undue harm to health workers, caregivers and the community. This document provides guidance to Member States on how to prioritize and adapt immunization services during the Covid-19 pandemic, and steps to mitigate the impact of the pandemic on vaccine-preventable diseases.