She is a Takemi Fellow at Harvard University in Boston, where for 10 years she has been a visiting scientist and a
Fulbright Fellow. She has been since 1976 a professor at
FIOCRUZ in
Rio de Janeiro, Brazil.
Whilst working at FIOCRUZ she has also spent time as a
Fulbright Fellow and Takemi Fellow in International Health at
Harvard University from 1990 to 1994 before becoming a visiting scientist with the New Diseases Group at
Harvard School of Public Health from 1994 to 2002. Possas also served as National Executive Secretary, National Technical Biosafety Commission (CTNBio), Ministry of Science and Technology, Brazil from 2001 to 2002 and Head, Research and Technological Development Unit, National AIDS Program,
Ministry of Health, Brazil, 2002–2011.
Possas, C. 1989. Epidemiologia e Sociedade: Heterogeneidade Estrutural e Saúde no Brasil [Epidemiology and Society: Structural Heterogeneity and Health in Brazil. Hucitec, São Paulo.
Possas, C. 1980. Saúde e Trabalho: a Crise da Previdência Social [Health and Labour: the crisis of Social Welfare in Brazil], [2nd edition in 1989]. Hucitec. [Winner award of honors from the Brazilian Society of Social Welfare Rights in 1981 for the best book on Social Welfare].