From 2006 to 2010, she was a correspondent in Washington for the State of São Paulo. She covered the American economic crisis, the war in Afghanistan, the elections of 2008, 2012, 2016. At the White House, she interviewed President George W Bush. She also covered the attacks of September 11, 2001. She conceived the award-winning "World of Walls" project, a multimedia special about the migration crisis made in four continents. She has been to Syria, Iraq, Turkey, Libya, Lebanon and Kenya several times reporting on refugees and the war. She was also the only Brazilian reporter who, in 2014 and 2015, covered the ebola epidemic in Sierra Leone.
She gained prominence in the context of the 2018 presidential election in Brazil when she signed a report on alleged electoral crimes in the campaign of candidate Jair Bolsonaro. She published that there was illegal funding for the Bolsonaro campaign on social networks conducted by party entrepreneurs. For her report, she was the target of persecution and hate attacks. Subsequently, in response to a questioning by the Supreme Electoral Court, statements from major social networks claimed that the Bolsonaro campaign did not buy content boost. However, these same social networks refused to provide information on the financing of content boost by entrepreneurs and companies linked to Bolsonaro, the subject of the article by Mello. In June, she published two more reports on the use of WhatsApp during the elections, this time with foreign marketing agencies. In July, nine months after the opening of investigations into the illegal use of WhatsApp shots in the 2018 election, not a single suspect had been heard by the police. In September 2019, almost a year after the election campaign, WhatsApp admitted for the first time that the 2018 Brazilian election had illegal use of massive messaging, with automated systems hired from companies.
Case Jair Bolsonaro
On February 18, 2020, during an interview with a group of sympathizers in front of the Dawn Palace, Bolsonaro insulted the journalist with a sexual innuendo: "She wanted to give the scoop at any price against me." The statement to CPMI to which the president referred was from Hans River do Rio Nascimento, who worked for Yacows, a company specializing in digital marketing, during the 2018 election campaign. Several parties and politicians and journalistic entities, who considered the speech an attack on democracy, repudiated the president's attitude.