Decreased immunity. Aids stands for acquired immune deficiency syndrome. It is caused by HIV (human immunodeficiency virus), which can be contracted through exchange of bodily fluids such as semen, vaginal secretions, blood, and breast milk. Hiv/aids causes a progressive decline in the function of the immune system, which leave the body susceptible to life-threatening infections.
Low defenses. The immune system main role is to defend us against infections. Immunodeficient patients might get very sick with an infection that is usually mild, such as a cold virus, that in normal people resolves within a week. Hiv is a virus that attacks the immune system decreasing our ability to fight infections, when the damage is significant, it is called aids.