HIV

Human Immunodeficiency Virus (HIV) is a virus that attacks the body’s immune system, specifically the CD4 cells (T cells), which help the immune system fight off infections. If left untreated, HIV can lead to the disease AIDS (Acquired Immunodeficiency Syndrome), a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Unlike some other viruses, the human body cannot completely get rid of HIV, meaning that once a person has HIV, they have it for life. However, with proper medical care, HIV can be controlled. The global effort to combat HIV has been significant, with substantial progress in diagnosis, treatment, and preventive measures, but it remains a major public health challenge worldwide.

Causes

HIV is transmitted through contact with infected bodily fluids, including:

1. Blood: Sharing needles or syringes with someone who is infected, or exposure through needlestick injuries in healthcare settings.
2. Sexual Contact: Through anal, vaginal, or oral sex with an HIV-positive individual without using a condom or taking pre-exposure prophylaxis (PrEP).
3. Mother-to-Child Transmission: An HIV-positive mother can transmit the virus to her child during pregnancy, childbirth, or breastfeeding.
4. Contaminated Transfusions: Through blood transfusions or organ and tissue transplants from an HIV-infected donor (very rare in countries where blood is tested for HIV).

It’s important to note that HIV cannot be transmitted through casual contact such as hugging, shaking hands, or sharing dishes with someone who is HIV-positive.

Symptoms

HIV symptoms vary depending on the stage of infection:

Acute HIV Infection

Within 2 to 4 weeks after infection with HIV, some people may experience an illness similar to the flu, often described as the «worst flu ever.» Symptoms can include:

1. Fever
2. Chills
3. Rash
4. Night sweats
5. Muscle aches
6. Sore throat
7. Fatigue
8. Swollen lymph nodes
9. Mouth ulcers

Not everyone will experience these symptoms, but they can be the first sign of HIV infection.

Chronic HIV Infection

As the infection progresses to this stage, HIV continues to multiply at low levels, and symptoms may not be noticeable for years. Without treatment, HIV can weaken the immune system, leading to AIDS.

AIDS

This is the most severe phase of HIV infection, where the immune system is badly damaged, and individuals become susceptible to opportunistic infections. Symptoms can include:

1. Rapid weight loss
2. Recurring fever or profuse night sweats
3. Extreme and unexplained tiredness
4. Prolonged swelling of the lymph glands
5. Prolonged diarrhea
6. Sores of the mouth, anus, or genitals
7. Pneumonia
8. Memory loss, depression, and other neurologic disorders

Early diagnosis and treatment with antiretroviral therapy (ART) can significantly slow the disease’s progression, improve quality of life, and extend lifespan for those living with HIV.

Diagnostics

The diagnosis of HIV involves a series of tests that detect the presence of the virus or antibodies produced in response to HIV infection:

1. Antibody/Antigen Tests: The most common initial screening tests, which can detect both HIV antibodies and the p24 antigen, part of the virus itself. These tests can identify HIV within 2 to 6 weeks after exposure.
2. Antibody Tests: These tests solely look for antibodies to HIV in the blood or oral fluid and are typically used for rapid tests that can give results in 30 minutes or less. However, they may not detect HIV until 3 to 12 weeks after infection.
3. Nucleic Acid Test (NAT): This test looks for the virus itself in the blood and can detect HIV 7 to 28 days after infection. It’s more expensive and used less often than antibody or antigen/antibody tests but can be useful in specific clinical situations.

If an initial test is positive, a follow-up test is necessary to confirm the diagnosis. Once diagnosed, additional tests are used to monitor the disease’s progression and the immune system’s health, such as CD4 T-cell counts and the viral load test, which measures the amount of virus in the blood.

Treatment

HIV treatment involves the use of antiretroviral therapy (ART), a combination of medicines that work to control the virus. The goals of ART are to reduce the viral load to undetectable levels, maintain or increase CD4 T-cell counts (thereby strengthening the immune system), reduce the risk of HIV transmission, and improve overall quality of life. Treatment specifics can vary based on individual health needs, but the core approaches are as follows:

1. Combination Therapy: ART usually combines three or more antiretroviral (ARV) drugs from at least two different drug classes to prevent the virus from multiplying. This is important to reduce the risk of drug resistance.
2. Drug Classes: ARVs are categorized into several classes based on how they fight HIV. These include nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), integrase strand transfer inhibitors (INSTIs), and others.
3. Starting ART: Current guidelines recommend that everyone diagnosed with HIV begin ART as soon as possible after diagnosis.
4. Monitoring and Adjustments: Treatment effectiveness is monitored through regular viral load and CD4 count testing. Medications may be adjusted based on these test results and any side effects experienced.
5. Preventing Transmission: Effective ART not only benefits the individual’s health but also significantly reduces the risk of HIV transmission to others. People on ART with an undetectable viral load («undetectable = untransmittable» or U=U) do not transmit HIV through sex.
6. Adherence: Consistent adherence to ART is crucial for its success. Missing doses can lead to drug resistance, making the virus harder to treat.
7. Support Services: Counseling, support groups, and other services can help people living with HIV adhere to their treatment plans and manage both the physical and emotional challenges of the disease.

HIV treatment has evolved dramatically since the early days of the epidemic, and with proper treatment, individuals with HIV can lead long, healthy lives. Ongoing research continues to develop new drugs and treatment strategies, including efforts towards an HIV cure and vaccine.

Prevention

Preventing HIV transmission is critical in controlling the spread of the virus. Effective prevention strategies include:

1. Use of Condoms: Consistently using condoms during sexual intercourse reduces the risk of transmitting or acquiring HIV.
2. Pre-exposure Prophylaxis (PrEP): A daily medication for people who do not have HIV but are at high risk of getting infected. When taken as prescribed, PrEP is highly effective at preventing HIV.
3. Post-exposure Prophylaxis (PEP): Taking antiretroviral medicines within 72 hours after a possible exposure to HIV can prevent the virus from establishing an infection.
4. Safe Injection Practices: Using sterile needles and syringes for each injection and not sharing injection equipment.
5. Testing and Treatment of Pregnant Women: HIV testing and treatment for pregnant women can significantly reduce the risk of mother-to-child transmission during pregnancy, childbirth, or breastfeeding.
6. Regular HIV Testing: Knowing one’s HIV status is essential for prevention. Regular testing allows individuals to make informed decisions about their health and prevention strategies.

Complications

Without treatment, HIV can lead to AIDS, where the immune system is severely damaged, leading to complications such as:

1. Opportunistic Infections: These are infections that occur more frequently or are more severe in individuals with weakened immune systems, including certain types of pneumonia, tuberculosis, and fungal infections.
2. Cancers: People with HIV are at increased risk for certain cancers, such as Kaposi’s sarcoma, non-Hodgkin lymphoma, and cervical cancer.
3. Neurological Complications: HIV can affect the nervous system, leading to conditions like HIV-associated neurocognitive disorders (HAND), peripheral neuropathy, and progressive multifocal leukoencephalopathy (PML).
4. Wasting Syndrome: Involuntary weight loss of more than 10% of body weight, accompanied by diarrhea, weakness, or fever.
5. Cardiovascular Disease: HIV increases the risk of cardiovascular diseases, including heart disease and stroke.

Conclusion

HIV remains a significant public health challenge, but advancements in prevention, diagnosis, and treatment have transformed the outlook for those living with the virus. Early and consistent treatment with antiretroviral therapy can control HIV, prevent transmission, and allow individuals to lead long, healthy lives. Preventive measures, including PrEP, condom use, and safe injection practices, are crucial in reducing new infections. Ongoing education, testing, and access to care are key components in the global fight against HIV, aiming not only to reduce the incidence of new cases but also to eliminate the stigma associated with the virus. The progress made in HIV research and care underscores the importance of continued investment in public health initiatives and research to further reduce the impact of HIV/AIDS worldwide.