HIV is an acronym for human immunodeficiency virus . HIV is the cause of acquired immunodeficiency syndrome or AIDS . AIDS is the final stage of HIV infection, resulting from the destruction of the immune system. HIV is a retrovirus that infects and destroys the CD4+ T cells of the immune system; The immune system is become weaker (immunodeficiency), and infected people are more vulnerable to illness caused by bacteria, viruses and other infectious agents. AIDS is a syndrome because it can have a wide variety of signs and symptoms, which depend on the effects of microorganisms against which the immune system is not able to defend itself. Under normal circumstances, many of these microorganisms would not cause disease. Therefore, the infections they give rise in people infected with HIV are called opportunistic. How is HIV transmitted? In people infected with HIV, the virus can be found in semen, vaginal secretions, blood and breast milk. Contagion occurs through contact with these products, which happens: In unprotected sexual intercourse (vaginal, anal, or oral). The virus enters the body through small wounds on the skin and mucous membranes that can happen in vaginal and anal intercourse or through mouth sores. In direct contact with blood . Sharing infected needles and syringes is one of the main sources of contagion. Sharps objects contaminated with infected blood are another potential source of infection. From mother to child , before or during childbirth and during breastfeeding. HIV / AIDS is a sexually transmitted infection because transmission is mainly through anal, vaginal and oral sex. HIV is not transmitted through the saliva, tears, sweat, feces, or urine of infected people . How can you tell if someone is infected with HIV? The diagnosis of HIV infection is made through laboratory tests that search for antibodies, antigens, or nucleic acids of the virus. Antibody tests can be done on blood or saliva samples. The body can take up to about 3 months after exposure to HIV to produce enough antibodies to be detected. Antigen tests are done on blood samples and look for parts of the virus, which are present in the blood between 11 and 30 days after infection. Virus nucleic acids can also be screened for in blood samples. After exposure to HIV, this is the fastest test to have positive results. It is also used to determine viral load. Who should have HIV diagnostic tests? Anyone who suspects to be infected or who has had a risky contact , that is, who knows that have been with someone who is infected in a situation that may have transmitted the virus, should go to a doctor as soon as possible, so that he can advise and prescribe the tests that must be done. It is usual that doctors include tests for HIV in routine laboratory tests prescriptions for health surveillance or in specific situations, namely during pregnancy or when another sexually transmitted infection is diagnosed. In this way it is possible to make a diagnosis as early as possible and to delay the progression to a serious, often fatal, disease. When someone is infected with HIV there are no symptoms? Flu-like symptoms (like fever, headache, muscle aches, malaise, among others) may occur 2 to 4 weeks after infection, but not in all cases. In addition, these symptoms can be very light and go unnoticed. Thus, it is not the occurrence of symptoms that allows someone to know if is infected. What does it mean to be HIV positive? It means that there are antibodies against this virus in the blood and therefore that the person have been infected with HIV. Who can become infected with HIV? Anyone, woman or man, regardless of sexual orientation, as well as babies during pregnancy, childbirth or breastfeeding. There are risk factors that increase the possibility of becoming infected , for example: Having unprotected sex. The risk is greatest with anal sex, followed by vaginal sex. In oral sex the risk is lower, but this is not without risk; Having multiple sexual partners; Change sexual partners frequently; Having other sexually transmitted infections, as many are associated with the formation of small sores or ulcers on the genitals, which are a possible entrance for the virus; Use of illicit drugs and sharing of needles and syringes. Who can transmit HIV? Anyone who is infected with HIV , whether or not have symptoms. Do people with HIV also have AIDS? Not necessarily . An HIV-infected person must meet additional criteria, related to opportunistic infections and the number of CD4+ T cells in the immune system, to be diagnosed with AIDS. AIDS is the final stage of HIV infection. Over time, HIV weakens the immune system and leads to the development of AIDS. When an HIV infection is identified, the objective is to delay its evolution to AIDS with drugs that counteract the multiplication of the virus (antiretroviral therapy) and of some microorganisms that cause opportunistic infections. The earlier the infection is detected, the greater the chances of delaying the process. With the early identification of HIV infection and the antiretroviral therapies currently available, many years can pass between infection and diagnosis of AIDS. There are people infected with HIV who never get AIDS. Are there treatments to eliminate HIV? No, HIV has no cure . Once someone is infected with HIV, there is no treatment that can eliminate the virus. Currently available treatments counteract the effects of the virus on the immune system ( antiretroviral therapy ) and help to prevent opportunistic diseases. With these treatments, many years can pass from HIV infection and the diagnosis of AIDS, or this diagnosis may never be reached. How is HIV / AIDS prevented, is there a vaccine? There is no vaccine against the human immunodeficiency virus (research studies are ongoing) and HIV infection has no cure. The only way to prevent infection is: Always use condoms during sexual intercourse (whether vaginal, anal or oral); Do not share or reuse needles and syringes; Not having multiple sex partners or changing sex partners frequently. Other measures: Pre-exposure prophylaxis (PrEP) is a regularly administered antiretroviral drug treatment that can be used in people with a very high risk of infection. It does not protect against other sexually transmitted infections and does not replace the aforementioned prevention measures. Post-exposure prophylaxis (PEP) is a treatment with antiretroviral drugs that can be done after a risky contact occurs, which can be occupational (in healthcare professionals) or non-occupational. It should be done as soon as possible after probable exposure and lasts for 28 days. Some data on HIV/AIDS Since it was first identified three decades ago, HIV infection has been diagnosed in more than half a million people only in the European Union / European Economic Area countries. In 2020 , these countries (not including Portugal) registered almost 15 thousand new cases , which is equivalent to about 3.7 cases per 100 thousand inhabitants. Sexual transmission between men was the main form of transmission. The ratio between cases in men and women was 3.2:1. In Portugal , between 1983-2019, 61 433 cases of HIV infection were registered, of which 22 835 were in the AIDS stage, and 15 213 deaths were reported. The infection in later stages was diagnosed mainly in heterosexual men, over 50 years old and from the central region of the country. In 2019, 778 new cases of HIV infection were diagnosed, which is equivalent to a rate of 7.6 cases per 100 thousand inhabitants. There were 172 AIDS cases and 197 deaths. Of the 2019 diagnoses, around 50% concern residents of the Lisbon Metropolitan Area (13.7 cases per 100 thousand inhabitants) and almost 70% were men, mainly in the 25-29 age group. In more than 90% of the cases, the transmission was sexual, with relationships between men representing about 57%. Author : Saraiva da Cunha Sources Direção Geral da Saúde. Infeção VIH e SIDA em Portugal 2020 . European Centre for Disease Prevention and Control. HIV infection and AIDS . World Health Organization. HIV/AIDS surveillance in Europe 2021 . The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
