HIV/AIDS

Most people infected with HIV in Switzerland contract the virus during unprotected sex. But the virus is also transmissible through shared drug paraphernalia and other routes. HIV infection usually progresses in several phases. The first symptoms are often similar to those of the flu: fatigue, exhaustion, night sweats, fever and swollen lymph nodes. Many interpret this as a harmless infection because the symptoms are so non-specific. In up to one third of cases, however, the infection is asymptomatic or atypical symptoms occur. An HIV infection can be reliably detected with an HIV test. Today, the disease can be treated well with medication and kept in check. It often takes many years for the disease to turn into the life-threatening immunodeficiency AIDS.

What is HIV/Aids?

HIV is the abbreviation for the “human immunodeficiency virus” or HI virus. It belongs to the group of retroviruses. The special feature is that these viruses can include their genetic material in the genetic material of their host cells. AIDS, on the other hand, refers to the disease that can result from an untreated infection with the HIV virus. However, if left untreated, it often takes many years for an infected person to develop the immune deficiency AIDS. The abbreviation AIDS means “Acquired Immune Deficiency Syndrome”. Despite good treatment options, AIDS is still a life-threatening disease.

Infection with HIV occurs through body fluids, usually during unprotected sex. But drug addicts who use shared paraphernalia can also become infected. In addition, babies can become infected during pregnancy, birth, or breastfeeding if mothers do not receive HIV therapy.

Without treatment, the infectious disease progresses in different phases – with and without symptoms. In a “fresh”, acute HIV infection, many describe the symptoms as flu-like: fever, fatigue, lassitude, night sweats and swollen lymph nodes. However, these signs are very non-specific and can occur in many diseases. In addition, the number and severity of symptoms often vary greatly from individual to individual. In up to one third of cases, however, these typical flu-like symptoms are absent or there are no symptoms at all.

The diagnosis “HIV” can be made with the help of an HIV test. We can detect antibodies and virus components in the blood of infected individuals with a high degree of certainty. A negative 4th generation HIV test, six weeks after the risk situation, rules out HIV infection. Today, effective drugs are available for the treatment of HIV and AIDS, which slow down the multiplication of the viruses and reduce the viral load in the body. They ensure that HIV does not become AIDS for as long as possible. Medication can often keep the HI viruses and the disease at bay for a long time. Those who have been infected with HIV can often lead a normal life with sufficient treatment. However, if the immunodeficiency AIDS breaks out, life is often in danger.

You can prevent an HIV infection and thus also the late consequence of AIDS by protecting yourself during sex with condoms or femidoms (safer sex). There is also HIV pre-exposure prophylaxis (PreP), which offers a very high level of protection against infection when used correctly and has been reimbursed by health insurance since July 1, 2024 if indicated. There are also safeguards for drug use, such as not sharing injecting equipment.

“To avoid drug-related side effects and the development of resistant HI viruses, it is strongly recommended that HIV pre-exposure prophylaxis with medication is carried out under medical supervision.”

HIV/AIDS – incidence and age

In Switzerland, the number of HIV diagnoses has been declining for many years. In 2018, fewer than 425 cases were reported to the Federal Office of Public Health (FOPH). By comparison, in the 1990s, the average number of cases per year was 1,300. About five out of every 100,000 residents were newly diagnosed with HIV. Since 2013, this represents a decline of around 30 percent.

Researchers see the reason for this in increased HIV testing of people who have a particularly high risk of infection. But increasingly earlier treatment of HIV patients, which reduces the risk of transmission to others, also plays a major role. The third factor for the declining numbers of new infections is probably prevention by means of medication (HIV chemoprophylaxis, PrEP). It protects HIV-negative people at high risk of infection.

In Switzerland, around 17,000 people were living with HIV in 2018. Globally, approximately 37.9 million are HIV-positive, as reported by the Joint United Nations Programme on HIV/AIDS (UNAIDS) (2019). The majority of HIV cases reported in Switzerland affect men, especially men who have sex with other men: Their share is – almost unchanged – at 79 percent. HIV and AIDS can, in principle, affect people of any age.

HIV/AIDS: Causes and risk factors

The cause of AIDS is the HI virus. This is a so-called retrovirus. Its special feature is that it can insert its own genetic material into that of the host cell. Unlike human cells, the HI virus does not store its genetic information in the form of deoxyribonucleic acid (DNA), but as ribonucleic acid, or RNA for short. It therefore belongs to the RNA viruses. The RNA is transcribed and then incorporated into the DNA of the foreign cell.

The HI virus has a protein envelope. It is such that the virus can attach itself to human immune cells, first and foremost the T-helper cells. These play an important role in the immune defense and fight pathogens such as bacteria, viruses, fungi or parasites. The HI virus destroys the T-helper cells as well as other immune cells and thus weakens the immune system in the long term. Dangerous pathogens then have an easier time and those affected are more susceptible to infections of all kinds. In addition, the virus damages various organs.

Infection with HIV – ways of transmission of the virus

You can become infected with the HI virus in different ways. Transmission occurs via body fluids such as semen, vaginal secretions and blood.

• Unprotected sex – this is the main route of infection. The HI virus is particularly transmissible during vaginal and anal sex. In contrast, the risk of infection is very low during oral sex without ingestion of sperm fluids or menstrual blood. Men who have sex with men are particularly at risk. But heterosexuals also so often become infected with HIV. Condoms/femidoms (for women) can protect against infection with the HI virus, but also against some other pathogens that cause sexually transmitted diseases (STDs).
• Drug use if you share paraphernalia with others, such as injecting equipment or needles.
• Needlestick injuries in the hospital or doctor’s office.
• During pregnancy, childbirth, or breastfeeding if the mother is HIV positive. However, the risk can be reduced by taking preventive measures.
• Blood transfusions – this transmission route is now almost eliminated in industrialized countries because blood products are subject to strict controls. But in developing countries, where hygiene standards are less stringent, transmission by this route is possible.

There is no risk of you becoming infected with HIV in your daily interactions. Handshakes, hugs, kisses (even intense French kisses), fondling or petting are not dangerous. Even if you share cutlery, dishes, glasses, towels or toilets, there is no risk of infection. However, you should not use common razors that pose a risk of injury with bleeding. It is not possible to transmit the HI viruses by droplet infection when coughing, sneezing or talking. This route of infection plays the main role in many other infectious diseases.

The likelihood of contracting HIV depends on several factors. The number of transmitted HI viruses is important, but so is the virulence (the “disease-making potential”) of the virus and your general health. High virus concentrations are found in the blood, semen, vaginal secretions, and on the surface of mucous membranes, such as in the intestine. In saliva, on the other hand, the virus concentration is much lower, so that no infections are possible. Unprotected anal and vaginal sex carry the greatest risk of contracting HIV.

Symptoms: HIV/AIDS with and without symptoms

HIV symptoms can vary greatly from person to person. In the case of an acute infection with HI viruses, many experience symptoms similar to those of the flu. However, they are nonspecific and can occur in the context of many other diseases. Thus, most do not immediately associate their symptoms with HIV infection. In up to one third, however, the infection phase proceeds without these flu-like symptoms or even without symptoms. Without therapy, it usually progresses in four phases – with and without symptoms.

Phase 1: Acute HIV infection with symptoms

Shortly after infection, the HI virus multiplies particularly strongly in the body. Two to four weeks after infection, the following flu-like symptoms may occur:

• Tiredness, fatigue, exhaustion
• Decreased physical performance
• Feeling of discomfort
• Fever
• Night sweats
• Diarrhea
• Swollen lymph nodes
• Swollen tonsils
• Headache
• Muscle and limb pain
• Loss of appetite
• Skin rash

However, these symptoms may be completely absent, so that an HIV test should be carried out after a risk situation regardless of the occurrence of symptoms. One to two weeks later, the symptoms usually subside on their own. In this phase, the risk of infection is particularly high because there are a lot of HI viruses in body fluids such as blood and sperm, as well as on the mucous membranes in the vagina, penis and rectum. These are already beginning their destructive work: they damage the T helper cells and thus the immune system. After six weeks at the latest, the virus can usually be detected in an HIV test in the laboratory.

Phase 2: Latent phase without symptoms

The acute phase is followed by a period of no or mild symptoms. The HI viruses can only multiply a little because the immune system fends off the pathogens and can keep them in check to a certain extent. This balance can be maintained for several years. Nevertheless, the HI viruses continue to damage the immune defenses and attack organs, such as the kidneys.

Phase 3: Chronic HIV stage with symptoms

Without treatment, the immune system is weakened further and further. And that has consequences. For example, these symptoms and diseases may occur at this stage:

• Night sweats
• Prolonged swollen lymph nodes
• Fever above 38.5 degrees Celsius for which no other reason can be found
• Diarrhea for more than four weeks
• White coatings on the edge of the tongue that cannot be wiped off (oral hairy leukoplakia)
• Shingles: It is caused by the varicella zoster virus, which is also responsible for chickenpox. An extremely painful skin rash in the area of the back or chest is typical.
• Fungal disease in the mouth, throat, or vagina that lasts longer than four weeks
• Listeriosis – infection with listeria (bacteria)
• Nerve damage to the extremities – pain, tingling, numbness

Phase 4: AIDS

At this stage, the HI virus is no longer under control and the immune deficiency AIDS breaks out. How many years pass from infection to the onset of the disease cannot be generally predicted. The time span varies from individual to individual and can range from a few months to many years. Various factors have an influence on this, for example the use of HIV medication, lifestyle or existing underlying diseases.

Doctors speak of AIDS when less than 200 T-helper cells are detectable per microliter of blood or an AIDS-defining illness occurs. Those who receive timely and adequate treatment for HIV infection can avoid this stage.

AIDS is associated with serious diseases, for example:

• Wasting syndrome: severe weight loss, fever, fatigue, prolonged diarrhea
• Pneumocystis pneumonia – a special form of pneumonia. The causative agent is the tubular fungus Pneumocystis jirovecii.
• Fungal diseases of the trachea, esophagus, bronchi and lungs
• Other infections, e.g. herpes, tuberculosis, toxoplasmosis, salmonellosis
• HIV-associated encephalopathy – a dangerous brain inflammation in which the HI virus attacks the nerve cells. Brain functions suffer – even to the point of dementia.
• Certain cancers, such as Kaposi’s sarcoma – a rare type of skin cancer that also affects the mucous membranes and internal organs. Non-Hodgkin’s lymphoma, CNS lymphoma, or cervical cancer may also develop.

HIV/Aids: Diagnosis with us

At the beginning of the diagnosis of HIV there is always a discussion between the patient and us about the medical history (anamnesis). The following questions are of interest to us:

• What are your symptoms?
• How long have they existed and to what extent are they pronounced?
• In which areas of the body do the complaints show themselves?
• Were there periods when the symptoms improved again?
• How would you describe your sex life?
• Have you had sexual contact with someone infected with HIV?
• Do you use drugs?
• Do you have any known underlying diseases?
• Are you taking any medications? If yes: Which and since when?
• What about your lifestyle?

Based on your answers, we can already make an initial assessment. This is usually followed by a physical examination, during which we palpate the lymph nodes, listen to the heart and lungs, or examine the skin, among other things.

HIV/AIDS: prevention, early detection, prognosis

The most important transmission route for HIV is unprotected sex – whether homosexual or heterosexual is irrelevant. This is where you can start yourself and prevent HIV infection by protecting yourself and others from becoming infected. The buzzword is “safer sex.”

• Use a condom during sex, both vaginal and anal. There are special condoms for women, the femidoms. This prevents blood, semen or vaginal fluid from getting onto open skin areas and the mucous membranes of the sexual partner.
• There is hardly any risk of infection during oral sex. Even if blood, semen or vaginal secretions get into the mouth, the risk of infection is very low. Only a few cases have been described worldwide in which a person has contracted HIV through oral sex.
• Avoid sex with frequently changing partners. Openly discuss a fling or one-night stand with your partner.

Other measures to prevent HIV infection include:

• Drug addicts should not share paraphernalia with others. Today, there are disposable syringes that minimize the risk of infection.
• Do not share pointed, sharp objects with other people, for example razors, razor blades or nail scissors – they can cause injuries. Contact with body fluids can infect others.
• When traveling to developing countries – if possible, do not have any medical treatments done that involve blood or the use of injections. Hygiene standards there are often less good than in industrialized countries.

HIV infection – prevent with medication

• HIV therapy: Have an existing HIV infection adequately treated. HIV therapy suppresses the multiplication of viruses in the body. In this way, you also cannot transmit HIV and do not endanger other people.
• Pre-exposure prophylaxis (PrEP)Pre-exposure prophylaxis (PrEP): People with an increased risk of infection take HIV medication as a preventative measure to protect them from contracting the HI virus. The active ingredients enter the cells of the mucous membranes. If the virus attacks the cells, however, it cannot reproduce there. PrEP is very effective. You can take the medication daily and permanently (continuous PrEP) or on demand (on-demand PrEP). However, the last option is not suitable for women because it takes some time for the protective effect to develop in the vaginal area. The medications require a prescription.
• Post-exposure prophylaxis (PEP): Drugs are used to prevent the spread of HIV in the body at an early stage. The drugs only make sense if the risk is actually very high that a person has become infected. Those affected must take the medication quickly – preferably within two hours, but no later than 48 hours after the risk situation.

HIV/AIDS in pregnancy

During pregnancy, childbirth and breastfeeding, HIV can be transmitted to the unborn child, baby or child. However, there are special measures to reduce this risk to practically zero. These include:

• HIV medications for HIV-positive expectant mothers during pregnancy (transmission prophylaxis) and subsequent drug treatment of the newborn,
• Cesarean section so that the baby does not have to pass through the birth canal and become infected there – after which the newborn receives temporary HIV medication,
• Refraining from breastfeeding.
• If you wish to have children, artificial insemination is also possible without the transmission of HIV.

Despite intensive research, there is as yet no vaccination that could protect against HIV. One reason is that the HI virus is extremely versatile and changes again and again. A large number of different subtypes of HI viruses are now known, against which a single vaccine would not be able to do much. Researchers would therefore need to develop multiple vaccines that specifically target the different types.

HIV/AIDS progression and prognosis

The course and prognosis of HIV infection cannot be generally predicted. They vary from individual to individual and depend on some additional factors. For example, existing underlying diseases, psychological factors or lifestyle play a role.

Most HIV-infected people can live a life without major limitations with sufficient treatment. The life expectancy of HIV-infected persons corresponds to that of the general population, provided that the HIV infection is detected early and treated throughout life.

Thanks to new drugs, the prognosis has improved decisively. This is because they can keep the viral load completely suppressed if taken correctly and regularly. In the early years after the discovery of HIV/AIDS, things were different: back then, many people died of HIV infection within a short period of time. Even in developing countries that lack access to HIV medications, the prognosis for affected individuals is often unfavorable.

Self-help groups

The exchange with people who are affected by the same disease can be a great support in coping with the disease. Advice on finding a suitable self-help group is available from Selbsthilfe Zürich. Self-Help Zurich and the University Hospital Zurich are cooperation partners in the national project “Health literacy thanks to self-help-friendly hospitals”.

HIV/AIDS: Treatment with drugs

To date, HIV/AIDS is not curable, but doctors can treat the disease well. The goal of HIV therapy is to keep the viral load suppressed and to strengthen the immune system on a sustained basis. Even if AIDS has broken out, there are still many treatment options, for example to fight infections.