HIV travels from host to host via blood.
It can be passed during vaginal, anal, and oral intercourse. However, it is not believed that kissing passes the disease. Before 1985, transfusions used by hemophiliacs were a major source of infection. Needles used to inject drugs, tattooing, and ear piercing are also ways to transfer this virus.
Pregnant women can pass it to the baby while it is still inside the uterus or by exposure to her blood during childbirth. It can also be passed through breast milk.
It can't, however, penetrate the skin or be transmitted by blood sucking insects such as mosquitoes and fleas or spread through the air, water or food.
It doesn't produce any specific symptoms. It basically just weakens your immune system and can lead to AIDS. AIDS stands for acquired immunodeficiency syndrome. (a syndrome is an occurrence of a characteristic group or pattern of symptoms.) AIDS can appear anytime from two to fifteen years to occur.
HIV constantly undergoes rapid genetic mutations in each of its victims that leaves the immune system playing constant catch up. During the late stages of the infection, the body may lose and replace two billion CD4 lymphocyte cells a day and new viruses appear at about 100 million to 680 million a day.
There are no cures, but treatments can help people live longer.
Since the virus mutates so quickly, it is very unlikely to be a vaccine available. However, 13 experimental AIDS vaccines have been given to 1,500 volunteers in the U.S. since 1988, though federal health officials reject any type of large-scale trials due to lack of confidence in the vaccine. The World Health Organization plans to test two vaccines in Thailand and Brazil in a desperate attempt.
Prevention is still the best defense.