On 13 January 2025, WHO published its first disease-agnostic guideline on contact tracing (in English) after two years of evidence retrieval and deliberations. This guideline was curated by a WHO steering group, a Guideline development group, and reviewed by an External review group under the Surveillance Systems department's leadership and with the Global Outbreak Alert and Response Network (GOARN) operational support team's collaboration, as well as the constant support from the WHO Guidelines Review Committee secretariat.
This guideline was developed to address the need for the development of evidence-based contact tracing strategies. It establishes definitions for "contact", "contact person", "contact tracing" and other associated concepts. It allows for improvement of contact tracing strategies and provides recommendations attempting to answer some, though not all, questions that arose during the 2019 coronavirus pandemic and other outbreaks. The use of this guideline begins once people have been diagnosed and the potential for transmission exists. It is not, however, intended to assist with case investigation.
The primary audience for this guideline includes WHO Member States, national public health agencies, WHO teams and other organizations which play roles in implementing or researching contact tracing efforts including NGOs, community-based groups, academic institutions, and UN agencies.
The guideline is now available in all six official languages on WHO website.
Looking ahead, to encourage the application of these concepts and definitions and the uptake of the recommendations, a practical implementation guidance is being developed. It will provide practical explanations, best practices, and standardized procedures to enhance the effectiveness of contact tracing strategies across diverse public health setting. More specifically, it will:
- identify key factors influencing decisions to start, to stop, to scale-up and to scale-down contact tracing;
- provide a systematic overview of methods used for contact person identification and to assess their applicability;
- provide a systematic overview of methods used for contact person follow-up and monitoring and to assess their applicability;
- provide a systematic overview of methods used for measuring the performance of the contact tracing strategies and assess their applicability; and
- define a minimum set of variables needed for contact tracing.
