The Human Immunodeficiency Virus, or HIV has been around for over 30 years. In that time it has caused the death of millions and infected millions more. Current estimates put total worldwide infections at around 33.1 million people. But what is it? Where did it come from? And why haven’t we been able to stop it?

History

HIV is now believed to be a descendant of Simian Immunodeficiency Virus, a virus that only affected monkeys. SIV is believed to be over 32,000 years old. Somehow, the virus managed to cross over to humans in the form of what we now know to be HIV.

There are theories of how SIV crossed over to HIV, but nothing has been proven yet. The phenomenon isn’t unknown, and isn’t restricted to HIV. The process itself is called “zoonosis.”

The first HIV cases were found in the US in 1980. A few gay men in California and New York developed illnesses that seemed immune to treatment. Each was treated in isolation, until doctors realized that there was a common theme.

The discovery prompted extensive testing, and the HIV virus was identified. It was soon after that the link between HIV and AIDS was also identified. It took a while to convince many, indeed, some “experts” still dispute that fact that HIV and AIDS are linked. However, it is commonly believed that HIV leads to AIDS.

What is it?

HIV is a lentivirus, which attacks the immune system. It is part of the retrovirus strain that attacks animals and humans alike. HIV seems unique, but shares many common factors with Simian Immunodeficiency Virus or SIV.

The HIV virus is a roughly spherical cell that can only been seen through an electron microscope. It is surrounded by a membrane with tiny spikes made up of proteins.

The core of the cell is bullet-shaped and contains the three enzymes needed to replicate the virus. There are also two copies of the RNA, essential for replication. The inclusion of this RNA is one of the reasons HIV is so difficult to treat. It is much more complicated than other viruses like influenza.

The HIV cell has nine genes. Three of the genes, called gag, pol and env, contain information needed to make structural proteins for new virus particles. The other six genes, known as tat, rev, nef, vif, vpr and vpu, code for proteins that control the ability of HIV to infect a cell, produce new copies of virus, or cause disease.

Symptoms

At first, there are no symptoms. A lentivirus literally means “slow virus.” It sits in the body and works very slowly. That’s why many of those infected have no idea they have the disease.

It’s perfectly possible to remain asymptomatic for up to 20 years, while other, rare cases can develop symptoms after a couple of years. The average period is between 8 and 10 years before symptoms develop.

Within weeks of infection, some people can develop symptoms of primary or acute infection which typically have been described as a “mononucleosis” or “influenza” like illness. This can range from minimal fever, aches, and pains to very severe symptoms.

It is important to not however, that not everyone develops these symptoms. Currently, we have no idea why that is. The primary infection then fades, and the person will become asymptomatic again.

Infected people develop a severe reduction in a type of cell in the blood (CD4 cells) that is an important part of the immune system. These cells, often referred to as T cells, help the body fight infections.

After the primary infection has passed, the CD4 cells will gradually decline, and with it the immune system. Sufferers may develop the mild symptoms of HIV such as vaginal or oral thrush, fungal infections of the nails, a white brush-like border on the sides of tongue called hairy leukoplakia, chronic rashes, diarrhea, fatigue, and weight loss.

It’s important to realize that it isn’t HIV that kills. It merely opens the door to opportunistic diseases to come in and take over. The reduction of T cells reduces the body’s capacity to fight infection, which results in failing health, and eventually death.

Treatment

For the longest time, there was no effective treatment for those infected with HIV. Drug therapies have advanced to where antiviral drugs can be used to reduce the spread, and treat some symptoms of the virus.

Initially we were only able to treat the symptoms of the disease and not the disease itself. Treatment consisted of fighting the opportunistic infections that were able to attack the body once the T cells were depleted.

Modern treatment of HIV is all about suppression. The virus still does not have a cure. Combination therapy is now available to reduce the virulence of the infection and to keep it under control. These consist of antiretroviral drugs that suppress the growth of HIV cells in the body.

The problem with this treatment is that it’s expensive. It isn’t available to poorer parts of society and it’s those parts that are most at risk. There is of course, Medicaid and Medicare, but even those resources are finite.

The Prognosis

Much work is still ongoing to find more and better treatments for the virus. Discoveries are being made all the time, which will eventually still filter down though society.

The problem is that those most at risk from HIV infection are also the ones without access to healthcare. With our health system only catering to those who can afford it, vulnerable people often have to go without treatment.

The Ryan White Program and the AIDS Drug Assistance Program are directed at those without insurance or access to drugs. As always, funding is limited so these programs have to do what they can with what they have. That often means waiting lists, and going without for some.

The continued funding for these programs is good news for HIV sufferers. The Affordable Care Act should also widen access to healthcare. However, limited funding and an ever-growing demand will put even these programs under severe pressure over the coming years.