AP BIOLOGY

Detailed explanation-1: -HIV cannot survive for long outside the human body, which means that the risk of contracting HIV from dried blood or semen is low. If a person suspects that they have come into contact with HIV in the last 72 hours, they can use an emergency prevention method called post-exposure prophylaxis (PEP).

Detailed explanation-2: -Scientists and medical authorities agree that HIV does not survive well outside the body, making the possibility of environmental transmission remote. HIV is found in varying concentrations or amounts in blood, semen, vaginal fluid, breast milk, saliva, and tears.

Detailed explanation-3: -HIV passes between people through blood and certain other body fluids, including semen, pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk.

Detailed explanation-4: -HIV can live outside of the body for as long as a few weeks, depending on the conditions. In most cases, though, the virus is inactive and unable to cause an infection within hours of being outside the body.

Detailed explanation-5: -The virus resides in brain macrophages or microglial cells and astrocytes which may be some of the longest living cells in the body. Here the virus can escape the immune system and antiretrovirals. The persistence of HIV in the brain has important consequences.