Maria Odette Santos Ferreira (4 June 1925 – 7 October 2018) was a Portuguese professor of microbiology who played an important role in research on HIV, through the identification of the HIV-2 virus in association with the Pasteur Institute of Paris. She was also the coordinator of the Portuguese programme to fight AIDS, overseeing the "Say no to a second-hand syringe" project, which resulted in the collection and exchange by pharmacies of 43 million used syringes between 1993 and 2008.