What is HIV/AIDS?

HIV (Human Immunodeficiency Virus) is a retrovirus that attacks the immune system, specifically CD4+ T cells, the "helper" cells that coordinate immune responses. Without treatment, HIV progressively destroys immune function, leaving the body vulnerable to opportunistic infections and cancers.

AIDS (Acquired Immunodeficiency Syndrome) is the late stage of HIV infection, defined by a CD4 count below 200 cells/mm³ or the presence of certain opportunistic infections. With modern treatment, most HIV-positive people never develop AIDS.

HIV Transmission
  • Sexual contact: Unprotected vaginal or anal sex
  • Blood exposure: Sharing needles, transfusion (now rare due to screening)
  • Mother-to-child: During pregnancy, birth, or breastfeeding
  • NOT transmitted by: Casual contact, kissing, sharing food, mosquitoes

Discovery: The Mystery Begins (1981)

On June 5, 1981, the CDC published a report describing five young gay men in Los Angeles with Pneumocystis carinii pneumonia (PCP), a rare infection seen only in severely immunocompromised patients. All five were previously healthy. Two had already died.[5]

Within weeks, reports poured in of gay men dying from PCP, Kaposi's sarcoma (a rare cancer), and other unusual infections. Doctors were baffled. The syndrome was initially called "GRID" (Gay-Related Immune Deficiency), but as cases appeared in hemophiliacs, injection drug users, and Haitian immigrants, it became clear this was something new.

In 1982, the CDC coined the term AIDS. Fear and stigma exploded. Patients were abandoned by families, fired from jobs, and evicted from homes. Blood banks refused to test donations. The Reagan administration remained largely silent.

Identifying the Virus (1983-1984)

The race to find the cause of AIDS became one of the most contentious episodes in science history.

In 1983, Luc Montagnier and Françoise Barré-Sinoussi at the Pasteur Institute in Paris isolated a retrovirus from a patient with lymphadenopathy. They called it LAV (Lymphadenopathy-Associated Virus).[2]

In 1984, Robert Gallo at the NIH announced the discovery of HTLV-III as the cause of AIDS, later shown to be the same virus as LAV. A bitter priority dispute followed, eventually resolved by acknowledging both teams. Montagnier and Barré-Sinoussi received the 2008 Nobel Prize; Gallo did not, creating lasting controversy.

The virus was officially named HIV in 1986. The discovery enabled development of blood tests, revealing the terrifying scope of the epidemic.

The Darkest Years (1985-1995)

For a decade, an AIDS diagnosis meant death, usually within two years. The virus was understood, but there was no effective treatment.

Activist groups like ACT UP (AIDS Coalition to Unleash Power) fought for research funding, faster drug approvals, and against discrimination. Their slogan "SILENCE = DEATH" galvanized action. Activists learned immunology and attended scientific conferences, fundamentally changing patient advocacy.

The Breakthrough: Combination Therapy (1996)

At the 1996 International AIDS Conference in Vancouver, researchers presented data on protease inhibitors, a new class of drugs that, combined with older antiretrovirals, could suppress HIV to undetectable levels.

HAART (Highly Active Antiretroviral Therapy) transformed HIV from a death sentence into a manageable chronic condition. Patients who had been preparing to die suddenly had futures. The death rate plummeted; in the US, AIDS deaths fell 47% from 1996 to 1997.[3]

"I had bought my burial plot. I had given away my things. Then the cocktail came, and I had to figure out how to live again."

- AIDS survivor, 1997

How HIV Works

HIV is a retrovirus: it uses reverse transcriptase to convert its RNA genome into DNA, which integrates into the host cell's chromosomes. This integration is why HIV cannot be completely eliminated from the body once established.

  1. Entry: HIV binds to CD4 and a co-receptor (CCR5 or CXCR4), fusing with the cell
  2. Reverse transcription: Viral RNA is converted to DNA
  3. Integration: Viral DNA inserts into human chromosomes (provirus)
  4. Replication: Provirus produces new viral particles
  5. Assembly and budding: New viruses released to infect more cells

Each step is a drug target. Modern antiretroviral therapy uses combinations targeting multiple steps, making resistance difficult to develop.

Modern Treatment

Today's antiretroviral therapy (ART) is simpler, safer, and more effective than ever:

The principle of U=U (Undetectable = Untransmittable) has been revolutionary: people on effective treatment cannot sexually transmit HIV. This has transformed prevention and reduced stigma.[4]

Prevention

Prevention Strategies
  • PrEP: Pre-exposure prophylaxis, a daily pill or injection that prevents infection in HIV-negative people
  • PEP: Post-exposure prophylaxis, emergency treatment within 72 hours of exposure
  • Condoms: Highly effective barrier protection
  • Treatment as prevention: People with undetectable viral load don't transmit
  • Needle exchange: Reduces transmission among people who inject drugs

The Ongoing Epidemic

Despite remarkable progress, HIV remains a global emergency:

Barriers include stigma, criminalization of key populations, healthcare access, and cost of treatment in low-income countries. The UNAIDS 95-95-95 targets aim for 95% of people with HIV to know their status, 95% of those to be on treatment, and 95% of those to be virally suppressed.

The Search for a Cure

HIV cannot currently be cured because the integrated provirus creates a "latent reservoir" in long-lived cells that persists despite treatment. Strategies under investigation include:

So far, only a handful of people have been cured, all through stem cell transplants for cancer, an approach not scalable to the broader epidemic.

Legacy

The HIV/AIDS epidemic fundamentally transformed medicine, drug development, and patient advocacy. Lessons from AIDS activism accelerated COVID-19 vaccine development. The infrastructure built for HIV response now addresses other diseases.

From the first terrifying reports in 1981 to today's effective treatment and prevention, the HIV story is one of tragedy, activism, science, and hope. It's not over, but the end of AIDS as a public health threat is within reach.

Sources

  1. UNAIDS. (2023). Global HIV & AIDS statistics: Fact sheet. unaids.org
  2. Barré-Sinoussi, F., et al. (1983). Isolation of a T-lymphotropic retrovirus from a patient at risk for AIDS. Science, 220(4599), 868-871.
  3. Fauci, A. S., & Lane, H. C. (2020). Four decades of HIV/AIDS: much accomplished, much to do. NEJM, 383(1), 1-4.
  4. Cohen, M. S., et al. (2016). Antiretroviral therapy for the prevention of HIV-1 transmission. NEJM, 375(9), 830-839.
  5. CDC. (1981). Pneumocystis pneumonia, Los Angeles. MMWR, 30(21), 1-3.
  6. Shilts, R. (1987). And the Band Played On: Politics, People, and the AIDS Epidemic. St. Martin's Press.