Slow blood flow can occur if there is a narrowing of the blood vessel. This can obstruct the flow. One common cause is atherosclerosis. There are deposition of cholesterol or lipids in the wall of the arteries which can narrow it. Other causes can be an inflammation. In the veins there can be slow flow where there is difficulty in pumping blood from legs towards the heart. If you feel any symptom, you should get an examination you need to get it checked by doctor. Any query, please feel free to ask.
Retrovirus, any of a group of viruses that belong to the family Retroviridae and that characteristically carry their genetic blueprint in the form of ribonucleic acid (RNA).
Named after the tissues they infect. For example, Adenoviruses cause common cold found in the adenoids tissues between the back of the throat and the nasal cavity. Today viruses are given a genus name ending in the word virus and a species name. If a virus affects bacteria it is called a bacteriophage or phage. HIV - RNA virus called retrovirus. HIV in a human host affects white blood cells. People with HIV eventually will get AIDS because more white blood cells become infected and produce new viruses.