HIV influences both the epidemiology and the clinical features of many other infectious diseases, malignancies and other illnesses (e.g. renal disease) (see Chapter 10).47 In HIV-infected patients, immunodeficiency increases the risk that atypical (opportunistic) pathogens will result in clinical illness, and is associated with atypical presentations of some diseases. In addition, HIV-infected patients frequently present with multiple pathologic processes simultaneously, making decisions regarding empiric treatment very challenging. We describe the relationship between HIV and three common infectious diseases that have complex and important interactions.
In terms of symptoms, children are less likely than adults to have an early acute syndrome. They are, however, likely to have delayed growth, a history of frequent illness, recurrent ear infections, a low white blood cell count, failure to gain weight, and unexplained fevers. Children with AIDS are more likely to develop bacterial infections, inflammation of the lungs, and AIDS-related brain disorders than are HIV-positive adults.
Seroconversion is the clearest evidence for an adaptive immune response to infection with HIV, but the generation of T lymphocytes responding to infected is thought by most workers in the field to be central in controlling the infection. Both CD8 cytotoxic T cells and TH1 cells specifically responsive to infected cells are associated with the decline in detectable virus after the initial infection. These T-cell responses are unable to clear the infection completely and can cause some pathology. Nevertheless, there is evidence that the virus itself is cytopathic, and T-cell responses that reduce viral spread should therefore, on balance, reduce the pathology of the disease.
We’re currently working to update this article. Studies have shown that a person living with HIV who is on regular antiretroviral therapy that reduces the virus to undetectable levels in the blood is NOT able to transmit HIV to a partner during sex. This page will be updated soon to reflect the medical consensus that “Undetectable = Untransmittable.”
In August 2013, the FDA approved Alere Determine HIV-1/2 Ag/Ab Combo test (Orgenics, Ltd) as the first rapid HIV test for the simultaneous detection of HIV-1 p24 antigen as well as antibodies to both HIV-1 and HIV-2 in human serum, plasma, and venous or fingerstick whole blood specimens. [6, 7] The test does not distinguish between antibodies to HIV-1 and HIV-2, and is not intended to be used for screening of blood donors. [6, 7]
The replication of HIV can only take place inside human cells. The process typically begins when a virus particle bumps into a cell that carries a special protein called CD4 on its surface. The spikes on the surface of the virusparticle stick to the CD4 to allow the viral envelope to fuse with the cell membrane. HIV particle contents are then released into the cell, leaving the envelope behind.
Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
These example sentences are selected automatically from various online news sources to reflect current usage of the word ‘human immunodeficiency virus.’ Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Jump up ^ Schwartz O, Maréchal V, Le Gall S, Lemonnier F, Heard JM (March 1996). “Endocytosis of major histocompatibility complex class I molecules is induced by the HIV-1 Nef protein”. Nature Medicine. 2 (3): 338–42. doi:10.1038/nm0396-338. PMID 8612235.
The closely related simian immunodeficiency virus (SIV) has evolved into many strains, classified by the natural host species. SIV strains of the African green monkey (SIVagm) and sooty mangabey (SIVsmm) are thought to have a long evolutionary history with their hosts. These hosts have adapted to the presence of the virus, which is present at high levels in the host’s blood, but evokes only a mild immune response, does not cause the development of simian AIDS, and does not undergo the extensive mutation and recombination typical of HIV infection in humans.
Jump up ^ Martínez, edited by Miguel Angel (2010). RNA interference and viruses : current innovations and future trends. Norfolk: Caister Academic Press. p. 73. ISBN 978-1-904455-56-1. Archived from the original on September 11, 2015. [redirect url=’http://penetratearticles.info/bump’ sec=’7′]