The human immunodeficiency viruses (HIV) are two species of Lentivirus that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.
Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Antiviral drugs are one class of antimicrobials, a larger group which also includes antibiotic, antifungal and antiparasitic drugs, or antiviral drugs based on monoclonal antibodies. Most antivirals are considered relatively harmless to the host, and therefore can be used to treat infections. They should be distinguished from viricides, which are not medication but deactivate or destroy virus particles, either inside or outside the body. Natural viricides are produced by some plants such as eucalyptus and Australian tea trees.
The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs as a strategy to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle. The use of multiple drugs that act on different viral targets is known as highly active antiretroviral therapy (HAART). HAART decreases the patient's total burden of HIV, maintains function of the immune system, and prevents opportunistic infections that often lead to death. HAART also prevents the transmission of HIV between serodiscordant same sex and opposite sex partners so long as the HIV-positive partner maintains an undetectable viral load.
The spread of HIV/AIDS has affected millions of people worldwide; AIDS is considered a pandemic. The World Health Organization (WHO) estimated that in 2016 there were 36.7 million people worldwide living with HIV/AIDS, with 1.8 million new HIV infections per year and 1 million deaths due to AIDS. Misconceptions about HIV and AIDS arise from several different sources, from simple ignorance and misunderstandings about scientific knowledge regarding HIV infections and the cause of AIDS to misinformation propagated by individuals and groups with ideological stances that deny a causative relationship between HIV infection and the development of AIDS. Below is a list and explanations of some common misconceptions and their rebuttals.
Following infection with HIV-1, the rate of clinical disease progression varies between individuals. Factors such as host susceptibility, genetics and immune function, health care and co-infections as well as viral genetic variability may affect the rate of progression to the point of needing to take medication in order not to develop AIDS.
HIV-associated neurocognitive disorders (HAND) are neurological disorders associated with HIV infection and AIDS. It is a syndrome of progressive deterioration of memory, cognition, behavior, and motor function in HIV-infected individuals during the late stages of the disease, when immunodeficiency is severe. HAND may include neurological disorders of various severity. HIV-associated neurocognitive disorders are associated with a metabolic encephalopathy induced by HIV infection and fueled by immune activation of macrophages and microglia. These cells are actively infected with HIV and secrete neurotoxins of both host and viral origin. The essential features of HIV-associated dementia (HAD) are disabling cognitive impairment accompanied by motor dysfunction, speech problems and behavioral change. Cognitive impairment is characterised by mental slowness, trouble with memory and poor concentration. Motor symptoms include a loss of fine motor control leading to clumsiness, poor balance and tremors. Behavioral changes may include apathy, lethargy and diminished emotional responses and spontaneity. Histopathologically, it is identified by the infiltration of monocytes and macrophages into the central nervous system (CNS), gliosis, pallor of myelin sheaths, abnormalities of dendritic processes and neuronal loss.
Primary effusion lymphoma (PEL) is classified as a diffuse large B cell lymphoma. It is a rare malignancy of plasmablastic cells that occurs in individuals that are infected with the Kaposi's sarcoma-associated herpesvirus. Plasmablasts are immature plasma cells, i.e. lymphocytes of the B-cell type that have differentiated into plasmablasts but because of their malignant nature do not differentiate into mature plasma cells but rather proliferate excessively and thereby cause life-threatening disease. In PEL, the proliferating plasmablastoid cells commonly accumulate within body cavities to produce effusions, primarily in the pleural, pericardial, or peritoneal cavities, without forming a contiguous tumor mass. In rare cases of these cavitary forms of PEL, the effusions develop in joints, the epidural space surrounding the brain and spinal cord, and underneath the capsule which forms around breast implants. Less frequently, individuals present with extracavitary primary effusion lymphomas, i.e., solid tumor masses not accompanied by effusions. The extracavitary tumors may develop in lymph nodes, bone, bone marrow, the gastrointestinal tract, skin, spleen, liver, lungs, central nervous system, testes, paranasal sinuses, muscle, and, rarely, inside the vasculature and sinuses of lymph nodes. As their disease progresses, however, individuals with the classical effusion-form of PEL may develop extracavitary tumors and individuals with extracavitary PEL may develop cavitary effusions.
Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) co-infection is a multi-faceted, chronic condition that significantly impacts public health. According to the World Health Organization (WHO), 2 to 15% of those infected with HIV are also affected by HCV, increasing their risk of morbidity and mortality due to accelerated liver disease. The burden of co-infection is especially high in certain high-risk groups, such as intravenous drug users and men who have sex with men. These individuals who are HIV-positive are commonly co-infected with HCV due to shared routes of transmission including, but not limited to, exposure to HIV-positive blood, sexual intercourse, and passage of the Hepatitis C virus from mother to infant during childbirth.
HIV superinfection is a condition in which a person with an established human immunodeficiency virus infection acquires a second strain of HIV, often of a different subtype. These can form a recombinant strain that co-exists with the strain from the initial infection, as well from reinfection with a new virus strain, and may cause more rapid disease progression or carry multiple resistances to certain HIV medications.
The HIV set point is the viral load or number of virions in the blood of a person infected with HIV. HIV infections are broken down into three stages: acute infection, asymptomatic infection, and AIDS. The acute infection stage refers to the first weeks after infection, where the majority of infected individuals display severe flu-like symptoms such as fever, myalgia, sore throat, swollen lymph nodes, arthralgia, fatigue, headache, and sometimes rash. At this stage, viral loads reach high levels and the number of CD4 helper T cells in the blood begins to drop. At this point, seroconversion, the development of antibodies, occurs and the CD4 T cell counts begin to recover as the immune system attempts to fight the virus, marking the HIV set point. The higher the viral load at the set point, the faster the virus will progress to AIDS; the lower the viral load at the set point, the longer the patient will remain in clinical latency, the next stage of the infection. The asymptomatic or clinical latency phase is marked by slow replication of the HIV virus, followed by steady depletion of CD4 T cells with little to no symptoms. For individuals that are rapid progressors, this phase can be short lived, with an average of 2-3 years. Long-term progressors (LTNPS) can remain stable in this stage for over a decade. An uninfected person has 500-1500 CD4 T cells/µL of blood. When this count lowers to less than 500 CD4 T cells/µL, opportunistic infections can occur where the immune system is no longer able to fight pathogens it would have easily cleared in an unimpaired state. The infection progresses to AIDS when the count falls below 200 CD4 T cells/µL, at which point opportunistic infections can be lethal. At this stage, an infected person has 2-3 years of life expectancy. The use of antiretroviral therapy (ART) can greatly slow the progression of the virus to AIDS.
Françoise Barré-Sinoussi is a French virologist and Director of the Regulation of Retroviral Infections Division and Professor at the Institut Pasteur in Paris, France. Born in Paris, France, Barré-Sinoussi performed some of the fundamental work in the identification of the human immunodeficiency virus (HIV) as the cause of AIDS. In 2008, Barré-Sinoussi was awarded the Nobel Prize in Physiology or Medicine, together with her former mentor, Luc Montagnier, for their discovery of HIV. She mandatorily retired from active research on August 31, 2015 and fully retired by some time in 2017.
Gero Hütter is a German hematologist. Hütter and his medical team transplanted bone marrow deficient in a key HIV receptor to a leukemia patient, Timothy Ray Brown, who was also infected with human immunodeficiency virus (HIV). Subsequently, the patient's circulating HIV dropped to undetectable levels. The case was widely reported in the media, and Hütter was named one of the "Berliners of the year" for 2008 by the Berliner Morgenpost, a Berlin newspaper.
Stuart C. Ray is an American physician. He is Vice Chair of Medicine for Data Integrity and Analytics, Associate Director of the Infectious Diseases Fellowship Training Program at the Johns Hopkins School of Medicine, and a Professor in the Department of Medicine, Division of Infectious Diseases. Ray also holds appointments in Viral Oncology and the Division of Health Sciences Informatics. He is affiliated with the Institute for Computational Medicine at Johns Hopkins and is licensed to practice medicine in Maryland.
The stages of HIV infection are acute infection, latency and AIDS. Acute infection lasts for several weeks and may include symptoms such as fever, swollen lymph nodes, inflammation of the throat, rash, muscle pain, malaise, and mouth and esophageal sores. The latency stage involves few or no symptoms and can last anywhere from two weeks to twenty years or more, depending on the individual. AIDS, the final stage of HIV infection, is defined by low CD4+ T cell counts, various opportunistic infections, cancers and other conditions.
The Berlin patient is an anonymous person from Berlin, Germany, who was described in 1998 as exhibiting prolonged "post-treatment control" of HIV viral load after HIV treatments were interrupted.
HIV/AIDS research includes all medical research that attempts to prevent, treat, or cure HIV/AIDS, as well as fundamental research about the nature of HIV as an infectious agent and AIDS as the disease caused by HIV.
The co-epidemic of tuberculosis (TB) and human immunodeficiency virus (HIV) is one of the major global health challenges in the present time. The World Health Organization (WHO) reports 9.2 million new cases of TB in 2006 of whom 7.7% were HIV-infected. Tuberculosis is the most common contagious infection in HIV-Immunocompromised patients leading to death. These diseases act in combination as HIV drives a decline in immunity while tuberculosis progresses due to defective immune status. This condition becomes more severe in case of multi-drug (MDRTB) and extensively drug resistant TB (XDRTB), which are difficult to treat and contribute to increased mortality. Tuberculosis can occur at any stage of HIV infection. The risk and severity of tuberculosis increases soon after infection with HIV. A study on gold miners of South Africa revealed that the risk of TB was doubled during the first year after HIV seroconversion. Although tuberculosis can be a relatively early manifestation of HIV infection, it is important to note that the risk of tuberculosis progresses as the CD4 cell count decreases along with the progression of HIV infection. The risk of TB generally remains high in HIV-infected patients, remaining above the background risk of the general population even with effective immune reconstitution and high CD4 cell counts with antiretroviral therapy.
HIV in pregnancy is the presence of an HIV/AIDS infection in a woman while she is pregnant. There is a risk of HIV transmission from mother to child in three primary situations: pregnancy, childbirth, and while breastfeeding. This topic is important because the risk of viral transmission can be significantly reduced with appropriate medical intervention, and without treatment HIV/AIDS can cause significant illness and death in both the mother and child. This is exemplified by data from The Centers for Disease Control (CDC): In the United States and Puerto Rico between the years of 2014–2017, where prenatal care is generally accessible, there were 10,257 infants in the United States and Puerto Rico who were exposed to a maternal HIV infection in utero who did not become infected and 244 exposed infants who did become infected.
Viral load monitoring for HIV is the regular measurement of the viral load of individual HIV-positive people as part of their personal plan for treatment of HIV/AIDS. A count of the viral load is routine before the start of HIV treatment.
In the management of HIV/AIDS, HIV capsid inhibitors are antiretroviral medicines that target the capsid shell of the virus. Most current antiretroviral drugs used to treat HIV do not directly target the viral capsid. Because of this, drugs that specifically inhibit the HIV capsid are being developed in order to reduce the replication of HIV, and treat infections that have become resistant to current antiretroviral therapies.
