Concern After Argentina's President Long Silence A puzzling silence has descended around Argentine President Cristina Fernandez. As of Thursday, it had been 37 days since she last spoke in public. And she hadn't posted any messages to Twitter since Dec. 13, when she fired off a typical volley of 20 tweets. That has been feeding speculation in Argentina about her health in the wake of surgery on her head in October, and questions about who is running the country. "She's decided to stay away from her duties in power," opposition Sen. Gabriela Michetti told the DyN news agency. "She's suffering from fragility and weakness," Michetti said. Maybe she's still determining the course, but for a while she's been uncomfortable in her role as president. Members of Fernandez's administration dismiss the questions, saying she's busy at work. Defense Minister Agustin Rossi said Thursday that opposition criticism makes him "laugh hard" because "the president is totally in command." But her aides have not explained why she has stayed out of the public eye, though Cabinet Chief Jorge Capitanich recently said that the president "is also a human being and needs rest" because "she still in the process of recovering her full health." Fernandez was long known for nearly daily speeches and constant tweets. But she was silenced for six weeks late last year when she underwent surgery on Oct. 8 to remove a blood clot. She returned to work on Nov. 18. Since her return, Fernandez has tried to reinvent her image, putting aside the all-black wardrobe she wore for three years as a sign of mourning for her late husband Nestor Kirchner. Economy Minister Axel Kicillof has said that Fernandez continues to have final say on all decisions and recently dismissed rumors of growing power struggles in her administration that were fed by a series of contradictory statements by Cabinet ministers. Kicillof complained of a "soap opera being created" by the media to try to destabilize the government. "They spend so much ink and they try to generate tensions, frictions," Kicillof said. Fernandez made her last public appearance on Dec. 10. Three days later, she made her last comments on Twitter criticizing a protest by police. Her last official photograph was taken on Dec. 19 at a meeting held at an Islamic center. Officials have said that she spent Christmas holidays with her family in Argentina's south and has since been meeting with her ministers at the presidential residence, although no images have been provided. She also reportedly visited her ailing mother at a Buenos Aires clinic on Wednesday, but the government has yet to confirm the information. Capitanich has said that Fernandez will travel to Cuba for a summit of the Community of Latin American and Caribbean States on Jan. 28 and to Venezuela for a meeting of the Mercosur trade bloc on Jan. 31.