When Alexei was ill at Spala, they only published bulletins that he was gravely ill, "from a fall", but the exact nature of the hemophilia was indeed never revealed publicly at the time. Many people close to the court knew, and so it was not a total secret,but the vast majority of Russians did not know. Yes, a death announcement was prepared for Alexei, but was not issued as he did recover after receiving the famous telegram from Rasputin.