AIOIS Trends TV News Finance Sports Podcasts Music Shop Ent Local Books Movies Dash Relax Gaming Kids Radio

Reddit Science

Wed, Oct 18, 2006
EBV What now?

Mon, Jan 24, 2022

Last 6 Hours
Last 1 Day
Last 3 Days
How to search by date range:
They can be chained together

This Week In Science!  IFLScience


Fri, Jan 14, 2022 12:00 AM PT

What Is a Mono Rash?  Verywell Health

Verywell Health

Wed, Nov 10, 2021 12:00 AM PT

Can you get mono twice?  Medical News Today

Medical News Today

Tue, Nov 17, 2020 12:00 AM PT


Epstein–Barr virus

The Epstein–Barr virus (EBV), formally called Human gammaherpesvirus 4, is one of the nine known human herpesvirus types in the herpes family, and is one of the most common viruses in humans. EBV is a double-stranded DNA virus.It is best known as the cause of infectious mononucleosis ("mono" or "glandular fever"). It is also associated with various non-malignant, premalignant, and malignant Epstein–Barr virus-associated lymphoproliferative diseases such as Burkitt lymphoma, hemophagocytic lymphohistiocytosis, and Hodgkin's lymphoma; non-lymphoid malignancies such as gastric cancer and nasopharyngeal carcinoma; and conditions associated with human immunodeficiency virus such as hairy leukoplakia and central nervous system lymphomas. The virus is also associated with the childhood disorders of Alice in Wonderland syndrome and acute cerebellar ataxia and, based on some evidence, higher risks of developing certain autoimmune diseases, especially dermatomyositis, systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, and multiple sclerosis. About 200,000 cancer cases globally per year are thought to be attributable to EBV.Infection with EBV occurs by the oral transfer of saliva and genital secretions. Most people become infected with EBV and gain adaptive immunity. In the United States, about half of all five-year-old children and about 90% of adults have evidence of previous infection. Infants become susceptible to EBV as soon as maternal antibody protection disappears. Many children become infected with EBV, and these infections usually cause no symptoms or are indistinguishable from the other mild, brief illnesses of childhood. In the United States and other developed countries, many people are not infected with EBV in their childhood years.


Epstein–Barr virus-associated lymphoproliferative diseases

Epstein–Barr virus-associated lymphoproliferative diseases (also termed EBV-associated lymphoproliferative diseases or EBV+ LPD) are a group of disorders in which one or more types of lymphoid cells (a type of white blood cell), i.e. B cells, T cells, NK cells, and histiocytic-dendritic cells, are infected with the Epstein–Barr virus (EBV). This causes the infected cells to divide excessively, and is associated with the development of various non-cancerous, pre-cancerous, and cancerous lymphoproliferative disorders (LPDs). These LPDs include the well-known disorder occurring during the initial infection with the EBV, infectious mononucleosis, and the large number of subsequent disorders that may occur thereafter. The virus is usually involved in the development and/or progression of these LPDs although in some cases it may be an "innocent" bystander, i.e. present in, but not contributing to, the disease.EBV-associated LPDs are a subcategory of EBV-associated diseases. Non-LPD that have significant percentages of cases associated with EBV infection (see Epstein–Barr virus infection) include the immune disorders of multiple sclerosis and systemic lupus erythematosus; malignancies such as stomach cancers, soft tissue sarcomas, leiomyosarcoma, and undifferentiated nasopharyngeal cancer; the childhood disorders of Alice in Wonderland syndrome; and acute cerebellar ataxia.About 95% of the world's population is infected with EBV. During the initial infection, the virus may cause infectious mononucleosis, only minor non-specific symptoms, or no symptoms. Regardless of this, the virus enters a latency phase in its host and the infected individual becomes a lifetime asymptomatic carrier of EBV. Weeks, months, years, or decades thereafter, a small percentage of these carriers, particularly those with an immunodeficiency, develop an EBV+ LPD. Worldwide, EBV infection is associated with 1% to 1.5% of all cancers. The vast majority of these EBV-associated cancers are LPD. The non-malignant, premalignant, and malignant forms of EBV+ LPD have a huge impact on world health.The classification and nomenclature of the LPD reported here follow the revisions made by the World Health Organization in 2016. This classification divides EBV+ LPD into five categories: EBV-associated reactive lymphoid proliferations, EBV-associated B cell lymphoproliferative disorders, EBV-associated NK/T cell lymphoproliferative disorders, EBV-associated immunodeficiency-related lymphoproliferative disorders, and EBV-associated histiocytic-dendritic disorders.


Epstein–Barr virus infection

There are several forms of Epstein–Barr virus (EBV) infection. These include asymptomatic infections, the primary infection, infectious mononucleosis, and the progression of asymptomatic or primary infections to: 1) any one of various Epstein–Barr virus-associated lymphoproliferative diseases such as chronic active EBV infection, EBV+ hemophagocytic lymphohistiocytosis, Burkitt's lymphoma, and Epstein–Barr virus positive diffuse large B-cell lymphoma, not otherwise specified); 2) non-lymphoid cancers such as Epstein–Barr virus associated gastric cancer, soft tissue sarcomas, leiomyosarcoma, and nasopharyngeal cancers; and 3) Epstein–Barr virus-associated non-lymphoproliferative diseases such as some cases of the immune disorders of multiple sclerosis and systemic lupus erythematosis and the childhood disorders of Alice in Wonderland Syndrome and acute cerebellar ataxia.


Epstein–Barr virus nuclear antigen 1

Epstein–Barr nuclear antigen 1 (EBNA1) is a multifunctional, dimeric viral protein associated with Epstein–Barr virus (EBV). It is the only EBV protein found in all EBV-related malignancies. It is important in establishing and maintaining the altered state that cells take when infected with EBV. EBNA1 has a glycine–alanine repeat sequence that separates the protein into amino- and carboxy-terminal domains. This sequence also seems to stabilize the protein, preventing proteasomal breakdown, as well as impairing antigen processing and MHC class I-restricted antigen presentation. This thereby inhibits the CD8-restricted cytotoxic T cell response against virus-infected cells. EBNA1 is expressed from the Qp promoter during all latency programs.


Epstein–Barr virus vaccine

As of 2021, a vaccine against Epstein–Barr virus was not yet available. The virus establishes latent infection and causes infectious mononucleosis. There is growing evidence that EBV is a trigger for Multiple Sclerosis. It is a dual-tropic virus, meaning that it infects two different host cell types — in this case, both B cells and epithelial cells. One challenge is that the Epstein–Barr virus expresses very different proteins during its lytic and its latent phases. Antiviral agents act by inhibiting viral DNA replication, but as of 2016 there was little evidence that they are effective against Epstein–Barr virus, they are expensive, they risk causing resistance to antiviral agents, and (in 1% to 10% of cases) can cause unpleasant side effects.Several clinical trials for a vaccine were conducted in 2006–2008. The viral proteins Gp350/220 are a primary target, but this would only block infection of B cells, not epithelial cells. A vaccine called MVA-EL has been also proposed as a target for EBV-positive cancers, but this would only be effective in combating EBV-related cancers, not the EBV infection itself. VLP (virus-like particle)-based EBV vaccines are also the subject of intensive research.In April 2018, the first human antibody that blocks Epstein-Barr Virus was discovered, called AMMO1. It blocks glycoproteins gH and gL. This discovery defines new sites of vulnerability on Epstein-Barr Virus, and neutralizes the dual-tropic infection (stopping both infection of B cells and epithelial cells).


History of virology

The history of virology – the scientific study of viruses and the infections they cause – began in the closing years of the 19th century. Although Louis Pasteur and Edward Jenner developed the first vaccines to protect against viral infections, they did not know that viruses existed. The first evidence of the existence of viruses came from experiments with filters that had pores small enough to retain bacteria. In 1892, Dmitri Ivanovsky used one of these filters to show that sap from a diseased tobacco plant remained infectious to healthy tobacco plants despite having been filtered. Martinus Beijerinck called the filtered, infectious substance a "virus" and this discovery is considered to be the beginning of virology. The subsequent discovery and partial characterization of bacteriophages by Frederick Twort and Félix d'Herelle further catalyzed the field, and by the early 20th century many viruses had been discovered. In 1926, Thomas Milton Rivers defined viruses as obligate parasites. Viruses were demonstrated to be particles, rather than a fluid, by Wendell Meredith Stanley, and the invention of the electron microscope in 1931 allowed their complex structures to be visualised.


Infectious mononucleosis

Infectious mononucleosis (IM, mono), also known as glandular fever, is an infection usually caused by the Epstein–Barr virus (EBV). Most people are infected by the virus as children, when the disease produces few or no symptoms. In young adults, the disease often results in fever, sore throat, enlarged lymph nodes in the neck, and tiredness. Most people recover in two to four weeks; however, feeling tired may last for months. The liver or spleen may also become swollen, and in less than one percent of cases splenic rupture may occur.While usually caused by Epstein–Barr virus, also known as human herpesvirus 4, which is a member of the herpesvirus family, a few other viruses may also cause the disease. It is primarily spread through saliva but can rarely be spread through semen or blood. Spread may occur by objects such as drinking glasses or toothbrushes or through a cough or sneeze. Those who are infected can spread the disease weeks before symptoms develop. Mono is primarily diagnosed based on the symptoms and can be confirmed with blood tests for specific antibodies. Another typical finding is increased blood lymphocytes of which more than 10% are atypical.


All rights reserved.
© 2022 All-in-one Internet Search.