ABSTRACT
This article approaches the emergence of social subjects - associativism - and the formation of horizontal circuits of solidarity, both of which were decisive processes for saving lives in favelas and suburbs in Rio de Janeiro during the Covid-19 pandemic.The impact of the pandemic has been enormous collective trauma that accentuated the collapse of health surveillance systems and generated a catastrophe and humanitarian crisis in the city. Solidarity and local collective cooperation processes had decisive effects as a new protagonism, generating synergy with health actions and social programmes. They contributed decisively to actions that made forms of immunological protection, food security, and access to basic care possible in adverse contexts with weak policies and severe limitations for social isolation.Highlighting the importance of collective health surveillance and assistance actions from local associations, this paper discusses public health actions in the favela territories that demonstrate how communities, universities, public officials, and public health networks can develop policies and projects to confront Covid-19 in the favelas.