संदेश
HIV AIDS
What is Hiv & Aids The human immunodeficiency virus ( HIV ) is a lentivirus (a subgroup of retrovirus ) that causes the acquired immunodeficiency syndrome (AIDS), [1][2] a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype. [3] Infection with HIV occurs by the transfer of blood, semen , vaginal fluid , pre-ejaculate , or breast milk . Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. HIV infects vital cells in the human immune system such as helper T cells (specifically CD4 + T cells), macrophages, and dendritic cells.[4] HIV infection leads to low levels of CD4 + T cells through a number of mechanisms, including apoptosis of uninfected bystander cells, [5] direct viral killing of infec...
