Castro was officially succeeded by his brother, Raul, as president of the country in 2008, two years after surgery for an undisclosed intestinal illness. Since then Castro has written frequent newspaper columns, which suddenly halted in June, prompting opponents to speculate about his health, CNN reported Thursday.
"The comandante is well, following his daily routine, reading, exercising," Alex Castro, one of Castro's sons, told Cuban state media.
Castro's message, released Wednesday, congratulated doctors who recently graduated from a Cuban medical institute. He also mentioned the 50th anniversary of the Cuban missile crisis and the exodus of doctors from the country after the 1959 revolution, CNN reported.