It has nothing to do with the theory of  autogenesis. The autogenic hypothesis postulates that the  organelles in eukaryotic cells were formed from the enfolding of  the cell membrane in prokaryotes.
How long does the flu last? For most healthy people, the flu is an uncomfortable but short-term illness that resolves itself as the immune system fights it off. Symptoms usually appear from one to four days after exposure to the virus, and they last five to seven days. For people who've had a flu shot, the symptoms may last a shorter amount of time, or be less severe. For other people, the symptoms may last longer. Even when symptoms resolve, you may continue to feel fatigued.
An otherwise healthy person who gets the flu will usually improve over two to five days. In some people that tired feeling may last for one week or more and very rarely the symptoms can last for several weeks (post influenza asthenia). A major concern when you get the flu is that complications can arise. This is not strictly a relapse, but the development of another illness. The risk is highest for those with diabetes; heart, lung, or kidney disease; and other chronic diseases that lower the body's resistance to infection. Persons over age 65 are also at greater risk of developing complications from the flu. A very serious complication associated with the flu is pneumonia. Shortness of breath, sharp chest pain on deep breathing, or fever lasting beyond five days are symptoms that may indicate pneumonia.