Summary: This study argues that, on the basis of the system of global health governance, different networks of experts have been set up as mechanisms for disseminating ideas based on scientific evidence, which promote cooperation and the implementation of recommendations originating from the World Health Organisation (WHO). However, the Covid-19 outbreak has made the limitations of these networks visible. In the case of Mexico, two main problems have been identified: first, the existence of experts who are members of a transgovernment network who take decisions based on political interests, leaving aside the recommendations stemming from the global approach; and secondly, a divided epistemic community, with rival groups, which is detrimental to the performance of these experts in their work as givers of ideas and knowledge broadcasters.