text: HIV/AIDS can but NOT ALWAYS have flu like symptoms for 3 days to two weeks upon contracting it.  After that time period, there are none.  However, other diseases easily caught when someone's immune system is compromised are a telltale sign.  They ususally appear in advanced stages of HIV/AIDS.  Caposi's sarcoma, a skin cancer, can appear in lesions on the skin.  Thrush, or a yeast infection in the mouth can appear (looks like a thick white coating on the toungue).  Pneumonia is common.  Diarrhea for lengthy stretches is also common.  Most people have no symptoms until AIDS develops fully, which is why it's important to get tested often so that HIV can be treated with drugs early.