WHO: Data
Provides centralized access to various WHO data sources (such as the Global Health Observatory, below). Includes access to the annual World Health Statistics report.
World Bank: Health, Nutrition and Population Portal
Includes databases and “dashboards” for health and population data, as well as a browsable index of topics and pages gathering material on individual subjects (such as COVID-19). The WHO also maintains a Data Catalog that includes many health datasets.
Organisation for Economic Co-Operation and Development
The OECD maintains multiple data portals. OECD.Stat includes data from OECD member nations and selected non-members across a variety of subjects (“themes”), including health. (The link above is prefiltered for the health theme.) The OECD Data page allows for customizable data visualizations across a range of subjects, including health, as well as links to reports and databases. (The link above is prefiltered for the health category.) The OECD also has a separate page devoted to data related to COVID-19.
Global Health Data Exchange
Huge inventory of surveys, censuses, vital statistics, and other health-related data. Note that not all data are available in full.
CDC: Health Topics A–Z
Browsable list of topics that includes definitions and subject-specific pages (see e.g. COVID-19).