HIV
HIV (Human Immunodeficiency Virus) is a virus that progressively attacks the immune system, weakening it (immunodeficiency) and increasing the risk of opportunistic infections and certain cancers.
AIDS (Acquired Immunodeficiency Syndrome) represents the advanced stage of HIV infection, when the immune defenses are so compromised that even common infections can become severe and potentially life-threatening.
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Related services:
Services for the diagnosis and treatment of HIV are available at:
- IRCCS ISMETT (Palermo).
- UPMC Salvator Mundi International Hospital (Rome).
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What Is HIV?
HIV is a virus that causes a progressive weakening of the immune system (immunodeficiency), specifically attacking CD4 T lymphocytes, which are essential for the immune response against infections and oncogenic agents.
Transmission can occur mainly in two ways:
- Horizontal: through unprotected sexual contact, via body fluids (blood, semen, vaginal secretions), or through contact with contaminated blood, for example, by using infected syringes or needles.
- Vertical: from mother to fetus during pregnancy or to the newborn during breastfeeding.
HIV has a high replicative capacity, especially in the early stages of infection. To multiply, it uses white blood cells, which are progressively destroyed, compromising the body’s ability to defend itself.
Without treatment, this process can eventually progress to AIDS (Acquired Immunodeficiency Syndrome). Many years may pass from initial infection to the onset of AIDS.
What Are the Symptoms of HIV?
HIV infection progresses through different stages, each characterized by specific symptoms. Not everyone shows obvious signs, but recognizing the pattern can help enable early diagnosis and timely treatment.
Initial Stage (Primary Infection): This occurs a few weeks after infection, when the virus replicates rapidly and the risk of transmission is highest. Symptoms are similar to those of influenza or mononucleosis and may include:
- Joint and muscle pain.
- Skin rashes.
- Fever and chills.
- Headache.
- Severe fatigue.
These symptoms usually resolve on their own within a few days or weeks.
Clinical Latency Stage: After the initial symptoms, the immune system partially contains viral replication. This phase can last several years, during which most people do not experience noticeable symptoms, although the virus continues to slowly damage immune defenses.
Symptomatic Stage: When the immune system becomes weaker, the first signs of immunodeficiency appear. Common symptoms include:
- Chronic diarrhea.
- Skin rashes or shingles (herpes zoster).
- Persistent fever.
- Frequent or hard-to-treat infections.
- Swollen lymph nodes.
- Weight loss.
- Persistent fatigue.
- Night sweats.
- Recurring cough and sore throat.
- Oral ulcers.
AIDS (Acquired Immunodeficiency Syndrome): In the final stage, the immune system is severely compromised and can no longer defend the body against infections and opportunistic cancers. AIDS is not a single disease, but a collection of clinical conditions caused by pathogens or tumors that take advantage of the weakened immune system.
Conditions indicative of AIDS may include:
- Esophageal candidiasis.
- Cervical or anal carcinoma.
- Cytomegalovirus infection.
- Primary brain lymphoma.
- Pneumonia.
- Kaposi’s sarcoma.
- Cerebral toxoplasmosis.
How Do You Diagnose HIV?
HIV diagnosis is performed through a simple blood test, which can detect HIV antibodies (IgG and IgM) and the p24 antigen, produced by the virus during the early stages.
After a risky exposure, it is recommended to take the test between one and three months from the last possible exposure. If the result is positive, the patient undergoes a confirmatory test to accurately establish the diagnosis.
Identifying the infection early is crucial: thanks to modern therapies, a person with HIV can achieve a life expectancy and quality of life similar to those living with other chronic conditions, such as diabetes or hypertension. Available treatments can block viral replication and prevent progression to AIDS.
How Is HIV Transmission Prevented?
Prevention is primarily based on using condoms during sexual activity and reducing risky behaviors. Complementary strategies include:
- Regular HIV testing: recommended for people with exposures or risky behaviors, even if they show no symptoms.
- PrEP (Pre-Exposure Prophylaxis): involves the controlled use of antiviral medication before potentially risky sexual encounters. It is intended for HIV-negative individuals and requires preliminary examinations and regular monitoring, including tests for other sexually transmitted infections (STIs).
It is important to remember that PrEP protects against HIV but does not protect against other STIs such as syphilis, gonorrhea, chlamydia, genital herpes, or viral hepatitis.
How Do You Treat HIV?
Currently, there is no definitive cure or vaccine that can eliminate HIV infection. However, thanks to advances in medicine, the infection can now be effectively controlled through antiretroviral therapy (ART), which has transformed HIV into a manageable chronic condition.
Antiretroviral therapy uses a combination of drugs that prevent the virus from replicating. This reduces the viral load to undetectable levels and protects the immune system from the progressive damage caused by the virus. Starting therapy as early as possible—enabled by timely HIV testing—is essential to achieve the best clinical outcomes.
There are several classes of anti-HIV drugs, each acting on different stages of the viral replication cycle. The doctor will select the most appropriate treatment based on:
- Other health conditions.
- Age.
- Possible drug resistance.
- Concomitant therapies.
The effectiveness of therapy largely depends on adherence: taking medications exactly as prescribed is crucial to maintain viral suppression, prevent resistance, and reduce the risk of infection progression.
Although therapy does not eliminate the virus, it allows people to live full lives, with a life expectancy comparable to the general population and a very low risk of transmitting the infection to others.
Reviewed November 2025.