Human Immunodeficiency Virus – or widely known as HIV – is a retrovirus that keeps on constantly changing, and this is why it still seems impossible to find a vaccine against it. Yet, scientists have already found substances that can make a patient's life longer in spite of his or her immunodeficiency.
One must know that HIV and AIDS are not the same. While the former is the virus, the disease might stay latent for years, or even decades before Acquired Immunodeficiency Syndrome breaks out. In the beginning, it might occur as a cold with fatigue, headaches and even fever, but it passes without taking any medications. It stays latent for a long time, while it is penetrating more and more CD4 white blood cells, which are responsible for recognizing germs, so by defeating them, HIV practically makes human body blind to every virus, thus they can invisibly reproduce themselves until they have infected so many cells that they even lead to symptoms.
And these are a lot more severe than the ones near the entry into the body. That is why we talk about AIDS itself from then on. Opportunistic infections – like fungal pneumonia – occur more and more often, since the first and foremost defensive line in the patient's body has fallen, and it cannot even fight against germs on the most basic level. Usually these banal infections lead to the patient's death within a couple of years.
The latent period can take longer with the right medications, so the patients might live several decades longer nowadays.