HIV and AIDS: Symptoms, Treatment & Prevention Guide

What Is HIV and How Does It Affect the Body?

HIV (Human Immunodeficiency Virus) is a virus that attacks and weakens the immune system by destroying CD4 cells (T-helper cells), which are crucial white blood cells that help the body fight infections. Without treatment, HIV progressively damages the immune system, potentially leading to AIDS. With modern treatment, the virus can be suppressed to undetectable levels, preventing immune system damage and transmission.

HIV stands for Human Immunodeficiency Virus. It is a retrovirus, meaning it uses RNA as its genetic material and reverse transcribes it into DNA to integrate into the host cell's genome. This unique characteristic is what makes HIV particularly challenging to eliminate from the body, as the viral DNA becomes permanently embedded in infected cells.

The primary target of HIV is the CD4+ T lymphocyte, commonly known as the T-helper cell. These cells play a crucial role in coordinating the immune response against pathogens. CD4 cells essentially act as the "conductors" of the immune system orchestra, signaling other immune cells when and how to respond to threats. When HIV infects and destroys these cells, the body's ability to fight off infections and certain cancers becomes progressively impaired.

The natural course of untreated HIV infection typically progresses through several stages over many years. After initial infection, the virus replicates rapidly, causing a spike in viral load and a temporary drop in CD4 cells. The immune system then mounts a response, partially controlling viral replication and entering a chronic phase that can last for years or even decades. However, without treatment, the virus continues to slowly deplete CD4 cells until the immune system is severely compromised.

How HIV Replicates

Understanding HIV replication helps explain why antiretroviral therapy is so effective. The HIV lifecycle involves several key steps, each of which can be targeted by different classes of antiretroviral drugs:

1. Attachment and Entry: HIV binds to CD4 receptors and co-receptors (CCR5 or CXCR4) on the cell surface, then fuses with the cell membrane to enter.
2. Reverse Transcription: The viral enzyme reverse transcriptase converts HIV RNA into DNA.
3. Integration: The enzyme integrase inserts viral DNA into the host cell's chromosome.
4. Transcription and Translation: The infected cell produces new viral RNA and proteins.
5. Assembly and Budding: New virus particles are assembled and released from the cell to infect other cells.

The Difference Between HIV and AIDS

HIV and AIDS are not the same thing, though the terms are sometimes incorrectly used interchangeably. HIV is the virus that causes infection, while AIDS (Acquired Immunodeficiency Syndrome) is the most advanced stage of HIV disease. A person can live with HIV for many years—often indefinitely with treatment—without ever developing AIDS.

AIDS is clinically defined when the CD4 cell count falls below 200 cells per cubic millimeter of blood (normal range is 500-1,500), or when certain opportunistic infections or cancers develop. With modern antiretroviral therapy, the vast majority of people living with HIV never progress to AIDS. Early diagnosis and consistent treatment are the keys to preventing this progression.

What Are the Symptoms of HIV Infection?

HIV symptoms vary by stage. Early symptoms (2-4 weeks after infection) may include fever, sore throat, swollen lymph nodes, rash, muscle aches, and fatigue—often mistaken for flu. Many people experience no symptoms initially. Without treatment, late-stage symptoms develop years later as the immune system weakens, including weight loss, recurring infections, and opportunistic diseases. The only way to know your HIV status is through testing.

One of the most important things to understand about HIV is that symptoms alone cannot diagnose the infection. Many people with HIV look and feel completely healthy for years. Conversely, the symptoms that do occur can easily be mistaken for other common illnesses. This is why testing is so critical—waiting for symptoms is not a reliable way to detect HIV.

Acute HIV Infection (Primary Infection)

Approximately 40-90% of people who acquire HIV will experience symptoms within 2-4 weeks of infection, during a phase called acute HIV infection or acute retroviral syndrome. This occurs when the virus is rapidly replicating and the immune system is mounting its initial response. During this period, the viral load is extremely high, making the person highly infectious.

Common symptoms of acute HIV infection include:

• Fever: Often the first symptom, typically low-grade but can be high
• Sore throat: May be painful and accompanied by difficulty swallowing
• Swollen lymph nodes: Particularly in the neck, armpits, and groin
• Rash: Light pink, irregular spots typically on the trunk, face, arms, and legs; usually not itchy
• Muscle and joint pain: Generalized body aches similar to flu
• Headache: Can range from mild to severe
• Fatigue: Persistent tiredness and weakness
• Night sweats: Drenching sweats that soak bedding
• Diarrhea: May be mild or severe
• Mouth ulcers: Painful sores in the mouth or throat

These symptoms typically last one to two weeks and resolve on their own, even without treatment. Many people dismiss them as a bad flu or mononucleosis. However, this acute phase represents a critical window for diagnosis and treatment initiation.

Chronic HIV Infection (Clinical Latency)

After the acute phase, HIV enters a prolonged period called clinical latency or chronic HIV infection. During this stage, the virus continues to replicate at low levels and slowly destroys CD4 cells, but most people experience few or no symptoms. This stage can last 10-15 years in some individuals without treatment, though it varies widely.

Some people may experience persistent generalized lymphadenopathy—chronically swollen lymph nodes in multiple areas of the body. Others remain completely asymptomatic. Without treatment, the viral load gradually increases and CD4 count decreases over time, eventually leading to symptomatic disease.

Late-Stage HIV and AIDS

Without treatment, HIV eventually weakens the immune system enough that the body becomes vulnerable to opportunistic infections and certain cancers. Signs that HIV may have progressed to a more advanced stage include:

• Rapid weight loss: Unexplained loss of more than 10% of body weight
• Recurring fever: Persistent or frequent fevers
• Chronic diarrhea: Lasting more than a month
• Persistent cough and shortness of breath: May indicate pneumonia
• Oral thrush: White patches in mouth caused by candida fungus
• Shingles (herpes zoster): Painful blistering rash
• Skin problems: Unusual rashes, lesions, or discoloration
• Night sweats: Severe, drenching sweats
• Memory problems and confusion: Cognitive changes
• Recurrent infections: Bacterial, viral, or fungal infections

How Is HIV Transmitted from Person to Person?

HIV is transmitted through contact with certain body fluids: blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk. The most common transmission routes are unprotected anal or vaginal sex, sharing needles or syringes, and mother-to-child transmission during pregnancy, birth, or breastfeeding (when untreated). HIV cannot be transmitted through casual contact, saliva, sweat, tears, or sharing food.

Understanding HIV transmission is essential for both prevention and reducing stigma. HIV is only transmitted through specific activities that involve contact with infected body fluids, and even then, transmission is not guaranteed with every exposure. Several factors influence the likelihood of transmission, including viral load, type of exposure, and presence of other sexually transmitted infections.

Sexual Transmission

Sexual contact is the most common route of HIV transmission globally. The risk varies significantly depending on the type of sexual activity:

Several factors can increase the risk of sexual transmission: having a high viral load, presence of other STIs (especially those causing genital sores or inflammation), menstruation, and lack of male circumcision. Conversely, consistent condom use reduces risk by approximately 80-90%, and having an undetectable viral load eliminates sexual transmission risk entirely.

Blood-to-Blood Transmission

HIV can be transmitted through contact with infected blood. This includes sharing needles or syringes for drug injection, which carries one of the highest transmission risks (approximately 1 in 160 per sharing incident). Needle-stick injuries in healthcare settings carry a lower risk (approximately 1 in 435). Blood transfusions and organ transplants in countries with robust screening programs pose negligible risk due to mandatory testing of all donations.

Mother-to-Child Transmission

Without intervention, the risk of mother-to-child transmission ranges from 15-45%. However, with proper prenatal care, antiretroviral treatment during pregnancy, appropriate delivery management, and avoidance of breastfeeding (or treatment during breastfeeding), the risk can be reduced to below 1%. In many developed countries, mother-to-child transmission has been virtually eliminated through these interventions.

How HIV Is NOT Transmitted

HIV cannot survive long outside the human body and is not transmitted through:

• Air or water
• Saliva, sweat, or tears
• Hugging, shaking hands, or casual contact
• Sharing food, drinks, or eating utensils
• Toilet seats, doorknobs, or other surfaces
• Mosquitoes or other insects
• Closed-mouth kissing

How Do You Get Tested for HIV?

HIV testing is simple, confidential, and widely available through healthcare providers, sexual health clinics, community organizations, and home testing kits. Tests include rapid tests (results in 20 minutes), laboratory antibody/antigen tests (most accurate), and RNA tests (earliest detection). For conclusive results, test 6 weeks after potential exposure and confirm at 3 months. Regular testing is recommended for anyone sexually active or at risk.

HIV testing is the only way to know your status. Because many people with HIV have no symptoms for years, millions of people worldwide are living with HIV without knowing it. Early diagnosis is crucial because it allows for earlier treatment initiation, better health outcomes, and prevention of transmission to others. Testing is quick, confidential, and in many places, free of charge.

Types of HIV Tests

Several types of HIV tests are available, each with different window periods (the time between infection and when a test can detect it):

Fourth-Generation Antigen/Antibody Tests (Recommended): These lab-based tests detect both HIV antibodies and p24 antigen (a protein produced during early HIV infection). They can detect HIV as early as 18-45 days after exposure, though most people will test positive by 6 weeks. This is currently the preferred testing method in most clinical settings.

Rapid Antibody Tests: These provide results in 20-30 minutes using a finger-prick blood sample or oral fluid. While convenient, they have a longer window period (23-90 days) because they only detect antibodies. A reactive rapid test requires confirmation with a laboratory test.

HIV RNA Tests (Nucleic Acid Tests): These detect the actual virus rather than antibodies and can identify HIV as early as 10-33 days after exposure. They are more expensive and typically used for confirming diagnosis, monitoring treatment, or screening blood donations.

Self-Tests (Home Tests): FDA-approved home tests allow people to test themselves in private. Oral fluid tests are most common, though finger-prick blood tests are also available. A reactive result should always be confirmed with a healthcare provider.

When to Get Tested

Testing recommendations vary based on risk factors:

• After potential exposure: Test at 6 weeks for reliable results, confirm at 3 months
• Sexually active adults: At least once in their lifetime; annually if multiple partners
• Higher-risk individuals: Every 3-6 months (men who have sex with men, people who inject drugs, sex workers, partners of people with HIV)
• Pregnancy: All pregnant people should be tested during prenatal care
• After sexual assault: Immediate testing with follow-up testing at appropriate intervals

Understanding Test Results

A negative result means no HIV antibodies or antigens were detected. If you're outside the window period, this result is reliable. If tested too soon after exposure, repeat testing may be needed.

A positive (reactive) result means HIV antibodies, antigens, or RNA were detected. All positive results require confirmation with an additional test. A confirmed positive result means you are living with HIV and should be connected to care immediately.

What Is the Treatment for HIV Infection?

HIV is treated with antiretroviral therapy (ART), a combination of medications taken daily that suppress viral replication. With consistent treatment, the viral load becomes undetectable, preventing disease progression, immune system damage, and sexual transmission (U=U). Treatment should begin as soon as possible after diagnosis. Modern ART regimens are highly effective, generally well-tolerated, and often consist of a single daily pill.

The development of antiretroviral therapy has transformed HIV from a fatal disease to a manageable chronic condition. People who start treatment early and take their medications consistently can expect to live long, healthy lives with a life expectancy approaching that of the general population. Treatment not only benefits the individual but also eliminates the risk of sexual transmission when viral suppression is achieved.

How Antiretroviral Therapy Works

ART works by interfering with different stages of the HIV lifecycle, preventing the virus from replicating. Modern treatment typically uses a combination of two or more drugs from different classes to maximize effectiveness and reduce the risk of drug resistance. The main classes of antiretroviral drugs include:

• Integrase Strand Transfer Inhibitors (INSTIs): Block the integrase enzyme that HIV uses to insert its DNA into human cells. These are typically the backbone of modern first-line regimens.
• Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs): Block reverse transcriptase, preventing HIV from converting its RNA to DNA.
• Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs): Also block reverse transcriptase but through a different mechanism.
• Protease Inhibitors (PIs): Block the protease enzyme needed to produce mature, infectious viral particles.
• Entry Inhibitors: Prevent HIV from entering CD4 cells.

Most people today take a single pill once daily that contains multiple medications. These fixed-dose combinations simplify treatment and improve adherence. First-line regimens typically include an INSTI plus two NRTIs, which are highly effective and well-tolerated.

When to Start Treatment

Current guidelines from WHO, DHHS, and other major organizations recommend starting ART as soon as possible after HIV diagnosis, regardless of CD4 count or symptoms. This approach, called "Treat All" or "Test and Start," improves outcomes and reduces transmission. Treatment should ideally begin within days to weeks of diagnosis, and same-day treatment initiation is offered in many settings.

Treatment Goals and Monitoring

The primary goals of ART are to:

1. Suppress viral load to undetectable levels (less than 200 copies/mL, often less than 50)
2. Restore and preserve immune function (CD4 count recovery)
3. Prevent HIV-related illness and death
4. Prevent HIV transmission to others

Most people achieve viral suppression within 3-6 months of starting treatment. Regular monitoring includes viral load testing (every 3-6 months initially, less frequently once stable) and periodic CD4 count measurement. Additional monitoring may include tests for kidney function, liver function, and lipid levels, depending on the specific medications used.

Importance of Medication Adherence

Consistent adherence to ART is crucial for treatment success. Missing doses can allow the virus to replicate, potentially leading to drug resistance and treatment failure. Adherence of 95% or higher is generally recommended, meaning no more than one missed dose per month for a once-daily regimen. If you're having difficulty with adherence, talk to your healthcare provider about solutions such as reminder systems, simplified regimens, or addressing side effects.

Side Effects and Drug Interactions

Modern ART is generally well-tolerated, and many people experience no side effects. When side effects occur, they are often mild and temporary, resolving within the first few weeks of treatment. Common side effects may include nausea, diarrhea, headache, fatigue, or dizziness. Serious side effects are rare but should be reported to your healthcare provider immediately.

Some antiretroviral drugs interact with other medications, supplements, or substances. Always inform your healthcare provider about all medications you take, including over-the-counter drugs and herbal supplements. Certain HIV medications interact with hormonal contraceptives, requiring alternative contraceptive methods.

How Can You Prevent HIV Infection?

HIV prevention includes multiple effective strategies: consistent condom use (80-90% effective), PrEP (pre-exposure prophylaxis, up to 99% effective), treatment as prevention (U=U), PEP after exposure (within 72 hours), not sharing needles, and male circumcision. Combining prevention methods provides the strongest protection. Regular testing allows early diagnosis and treatment initiation.

HIV prevention has advanced dramatically, and today there are more options than ever to protect against infection. The most effective approach combines multiple prevention strategies based on individual circumstances and risk factors. No single method is perfect, but used together, these strategies can virtually eliminate HIV transmission risk.

Pre-Exposure Prophylaxis (PrEP)

PrEP is medication taken by HIV-negative people to prevent HIV infection. When taken consistently as prescribed, PrEP is approximately 99% effective at preventing HIV from sex and at least 74% effective for people who inject drugs. PrEP is a game-changer in HIV prevention and is recommended for anyone at substantial risk of HIV acquisition.

Who should consider PrEP:

• Anyone with an HIV-positive sexual partner (especially if partner not on treatment or viral load unknown)
• Men who have sex with men who have multiple partners or inconsistent condom use
• Anyone who has had a recent STI
• People who inject drugs and share equipment
• Anyone who engages in transactional sex
• Anyone who requests PrEP based on their assessment of their own risk

PrEP options:

• Daily oral PrEP: Taking a pill once daily provides continuous protection
• On-demand PrEP (2-1-1): For men who have sex with men, taking pills before and after sex (not for other populations)
• Long-acting injectable PrEP: Cabotegravir injections every 2 months, shown to be even more effective than daily pills

Post-Exposure Prophylaxis (PEP)

PEP is emergency medication taken after potential HIV exposure to prevent infection. It must be started within 72 hours of exposure (the sooner the better) and involves taking antiretroviral drugs for 28 days. PEP is used for emergency situations such as condom breakage, sexual assault, or needle-stick injuries when the source is known or suspected to have HIV.

Condoms and Barrier Methods

When used correctly and consistently, condoms reduce HIV transmission risk by approximately 80-90%. They also protect against other STIs and pregnancy. For maximum effectiveness, use condoms with water-based or silicone-based lubricant (oil-based lubricants can damage latex condoms). Internal (female) condoms are an alternative that give the receptive partner more control over protection.

Treatment as Prevention

People living with HIV who achieve and maintain an undetectable viral load cannot transmit HIV sexually. This concept, known as "Undetectable = Untransmittable" or U=U, has been validated by multiple large studies and endorsed by every major health organization. U=U means that effective treatment is also prevention, benefiting both the individual and their partners.

Other Prevention Strategies

• Harm reduction for people who inject drugs: Access to sterile needles and syringes, opioid substitution therapy, and supervised injection facilities reduce HIV transmission among people who inject drugs.
• Male circumcision: Reduces HIV acquisition risk for heterosexual men by approximately 60% and is recommended by WHO in high-prevalence settings.
• Prevention of mother-to-child transmission: Prenatal testing, treatment during pregnancy, and appropriate infant feeding practices can reduce transmission risk to below 1%.
• Regular STI testing and treatment: Having other STIs increases susceptibility to HIV; treating STIs reduces this risk.

What Is It Like Living with HIV Today?

Living with HIV today is dramatically different from the early epidemic. With modern treatment, people with HIV can live long, healthy lives with near-normal life expectancy. They can work, travel, have relationships, and have children without transmitting the virus. While stigma remains a challenge, medical advances have transformed HIV into a manageable chronic condition requiring regular medication and healthcare visits.

The experience of living with HIV has been revolutionized by advances in treatment. Where a diagnosis once meant a shortened lifespan and significant illness, today it means managing a chronic condition much like diabetes or hypertension. Most people on effective treatment report good quality of life, with the main challenges often being stigma rather than the virus itself.

Physical Health and Longevity

People who start treatment early and maintain viral suppression have a life expectancy approaching that of the general population. The key factors for long-term health include early diagnosis, consistent treatment adherence, regular medical care, and attention to overall health through exercise, nutrition, and avoiding smoking and excessive alcohol.

Some people with HIV may face higher risks of certain conditions as they age, including cardiovascular disease, kidney disease, and some cancers. Regular health monitoring and preventive care help manage these risks. The HIV care team typically includes not just infectious disease specialists but also primary care providers who address overall health needs.

Relationships and Sexual Health

People with HIV can have fulfilling romantic and sexual relationships. With U=U (Undetectable = Untransmittable), people on effective treatment cannot transmit HIV sexually, removing barriers that once existed. Disclosure of HIV status is a personal decision that involves weighing various factors, though many find that open communication strengthens relationships.

For serodifferent couples (where one partner has HIV and the other doesn't), multiple prevention options exist: the HIV-positive partner maintaining an undetectable viral load, the HIV-negative partner taking PrEP, or using condoms. Many couples use a combination of methods for added peace of mind.

Having Children

People with HIV can have biological children without transmitting the virus. For HIV-positive people who are pregnant or planning pregnancy, proper medical care and treatment reduce mother-to-child transmission risk to below 1%. Conception can occur naturally if the HIV-positive partner has an undetectable viral load, or through assisted reproduction techniques if additional protection is desired.

Work, Travel, and Daily Life

HIV does not limit most activities of daily life. People with HIV can work in any profession, travel to most countries (though some countries have entry restrictions), participate in sports, and live without significant limitations. Modern treatment regimens are simple—often just one pill daily—and fit easily into normal routines.

Addressing Stigma

Despite medical advances, stigma remains one of the biggest challenges facing people with HIV. Discrimination, misinformation, and prejudice can affect mental health, relationships, and access to care. Support groups, counseling, and advocacy organizations can help people navigate these challenges. Education and awareness-raising continue to be important for reducing stigma in society.