The Human Immunodeficiency Virus (HIV) targets the immune system and weakens people’s defenses against infections and some types of cancer. As the virus destroys and impairs the function of immune cells, infected individuals gradually become immunodeficient. Immune function is typically measured by CD4 cell count.
Immunodeficiency results in increased susceptibility to a wide range of infections, cancers and other diseases that people with healthy immune systems can fight off.
The most advanced stage of HIV infection is Acquired Immunodeficiency Syndrome (AIDS), which can take from 2 to 15 years to develop depending on the individual. AIDS is defined by the development of certain cancers, infections, or other severe clinical manifestations.
Signs and symptoms
The symptoms of HIV vary depending on the stage of infection. Though people living with HIV tend to be most infectious in the first few months, many are unaware of their status until later stages. The first few weeks after initial infection, individuals may experience no symptoms or fever, headache, rash, or afternoon throat.
As the infection of the immune system, an individual can develop other signs and symptoms, such as swollen lymph nodes, weight loss, fever, diarrhea and cough. Without treatment, they could also develop severe illnesses such as tuberculosis, cryptococcal meningitis, severe bacterial infections and cancers such as lymphomas and Kaposi’s sarcoma, among others.
HIV can be transmitted via the exchange of a variety of body fluids from infected individuals, such as blood, breast milk, semen and vaginal secretions. Individuals can not be infected through ordinary day-to-day contact such as kissing, hugging, shaking hands, or sharing personal objects, food or water.
Behaviours and conditions that put individuals at greater risk of contracting HIV include:
having unprotected anal or vaginal sex;
having another sexually transmitted infection such as syphilis, herpes, chlamydia, gonorrhoea, and bacterial vaginosis;
sharing contaminated needles, syringes and other injecting equipment and drug solutions when injecting drugs;
receiving unsafe injections, blood transfusions, tissue transplantation, medical procedures that involve unsterile cutting or piercing; and
experiencing accidental needle stick injuries, including among health workers.
Serological tests, such as RDTs or enzyme immunoassays (EIAs), detect the presence or absence of antibodies to HIV-1/2 and / or HIV p24 antigen. No single HIV test can provide an HIV-positive diagnosis. It is important that these tests have been validated and are based on HIV prevalence of the population being tested. HIV infection can be detected with great accuracy, using WHO prequalified tests within a validated approach.
It is important to note that serological tests detect antibodies are produced by an individual as part of their immune system to fight off foreign pathogens, rather than direct detection of HIV itself.
Most individuals develop antibodies to HIV within 28 days of infection and therefore antibodies may not be detected early, during the so-called window period. This early period of infection represents the time of greatest infectivity; however HIV transmission can occur during all stages of the infection.
It is the best practice to also retest all people initially diagnosed as HIV-positive before they are in control and / or treatment to rule out any potential testing or reporting error. Notably, once a person diagnosed with HIV and has started treatment they should not be retested.
Testing and diagnosis of HIV-exposed infants has been a challenge. For infants and children less than 18 months of age, serological testing is not sufficient to identify HIV infection. mothers living with HIV. However, new technologies are now available to perform the test at the point of care and enable the return of the result on the same day to accelerate the appropriate linkage and treatment initiation.
HIV testing services
HIV testing should be voluntary and the right to decline testing should be recognized. Mandatory or coerced testing by a health care provider, authority, or by a partner or family member is not acceptable as it undermines good public health practice and infringes on human rights.
New technologies to help people implement HIV self-testing as an additional option to encourage HIV diagnosis. HIV self-testing is a process whereby a person performs a test. HIV self-testing does not provide a definitive HIV-positive diagnosis
Sex couples and couples who inject drugs people diagnosed with HIV infection are likely to have HIV positive. WHO recommends notification services to HIV-assisted partners as a simple and effective way to achieve HIV infection.
All HIV testing services must follow the 5 principles C recommended by WHO:
Fix the test results
Connection (links with care, maintenance and other services).
People can reduce the risk of HIV infection by limiting exposure to risk factors. The key approaches to HIV prevention, used in combination, are listed below.
Use of male and female condoms
The use of true and constant male and female condoms during vaginal or anal penetration may protect against the spread of sexually transmitted infections, including HIV. Evidence suggests that latex condoms have an 85% or more protective effect against HIV and other sexually transmitted infections (STIs).
Testing and counseling for HIV and STIs
It is strongly recommended to test HIV and other STIs for everyone exposed to any risk factors. In this way, people learn from their own state of infection and access without delaying the necessary prevention and treatment services. WHO also recommends offering tests for couples or couples. In addition, WHO recommends an approach approach of co-sited partners to people with HIV to get support for their health care providers.
Testing and counseling, links to TB treatment
Tuberculosis (TB) is the most common disease and cause of death among people with HIV. This is fatal if it is not detected and there is an HIV-related death.
Early detection of tuberculosis and its initial association with tuberculosis treatment and antiretroviral therapy can prevent this death. TB screening should be offered routinely in HIV care and treatment. Individuals diagnosed with HIV and actively treated for TB (including multidrug-level TB) and ART. TB preventive therapy should be given to all people with HIV who do not have active TB.
Voluntary Voluntary Male Circumcision (VMMC)
Male medical circumcision reduces the risk of heterosexual HIV infection in men by about 60%. This is a key prevention intervention supported in 15 countries in East and South Africa (ESA) with high HIV prevalence and low rates of male circumcision. VMMC is also considered a good approach for reaching men and adolescent boys who often do not seek health care services. Since the 2007 WHO recommendation for VMMC as an additional prevention strategy, nearly 15 million men and teenagers at ESA have provided a package of services that includes HIV testing and education on safe sex and condom use.
Use of antiretroviral drugs for prevention
Benefits of prevention of ART
The 2011 trials have confirmed that if HIV positive people adhere to effective antiretroviral regimens, the risk of transmitting the virus to an uninfected partner can be reduced by up to 96%. WHO recommendations for starting antiretroviral treatment (ART) in all people living with HIV will contribute to HIV transmission.
Pre-exposure prophylaxis (PrEP) for HIV negative partners
HIV oral PrPP is an HIV-negative person to block HIV acquisition. More than 10 randomized controlled trials have demonstrated the effectiveness of PrEP in reducing HIV transmission in various populations including serodiscordant heterosexual couples (in which one partner is infected and the other is not), who have sex with men, transgender women, high-risk heterosexual couples and people who inject drugs.
WHO recommends PrEP as a preventive option for people with substantial risk of HIV infection as part of a combination of preventive approaches. WHO has also provided this recommendation to HIV-negative women who are pregnant or breastfeeding.
Prophylaxis after exposure to HIV (PEP)
Post-exposure prophylaxis (PEP) is the use of antiretroviral drugs within 72 hours of exposure to HIV to prevent infection. PEP includes counseling, first aid, HIV testing and 28-day course of antiretroviral treatment with advanced care. WHO recommends the use of PEP for occupational and non-occupational exposures and for adults and children.