HIV survival conditions

Dear Ask The Doctor: If a surface were to come into contact with HIV contaminated blood, but the blood was rinsed off the surface, would HIV remain on that surface like a germ? Or can HIV only stay "alive" in blood? For example, what if an HIV positive person were to brush their teeth and spit some blood into the sink . . . would the sink need to be disinfected, or is everything okay as long as the blood is washed down the sink? In the event that disinfecting is needed, do common household antibacterial cleaners, or just plain old soap work? And what about dried blood? Thanks!

Dear Kristin: The HIV virus needs to be inside the white cells and use their internal structures to replicate and survive. No sooner the body fluid containing the HIV virus starts to dry, 90% to 99% of the virus present becomes disabled upon drying. The HIV virus is very fragile when is outside the human body, like on the floor or on an outer surface and is not likely to survive an important amount of time in outside world. The only studies on the survival of HIV outside the body have been done in the laboratory under controlled scientific conditions. These studies have shown that HIV is not affected by extreme cold, but it is destroyed by temperatures of 60 degrees centigrade and above, detergents or disinfectants (bleach). In HIV contaminated blood when store in blood banks at 4 C , the virus may live no longer than 3 weeks or until the white cells fade away, maybe in frozen state could survive for years. The virus does not spread through casual contact such as preparing food, sharing towels and bedding, or via swimming pools, telephones, or toilet seats. The virus is also unlikely to be spread by contact with saliva, unless it is contaminated with blood.