Hepatitis A vaccine
Encyclopedia
Hepatitis A vaccine is a vaccine against the hepatitis A
virus. The first successful vaccine against it was invented by Maurice Hilleman
at Merck
. The vaccine protects against the virus in more than 95% of cases and provides protection from the virus for at least ten years. The vaccine contains inactivated Hepatitis A virus which stimulates active immunity against a future infection.
The vaccine was first phased in around 1996 for children living in high-risk areas. In 1999, it was spread to areas with elevating levels of infection. Today, in the U.S., the vaccine is strongly recommended for all children 12 to 23 months of age in an attempt to eradicate the virus nationwide. The original FDA license for Havrix by GlaxoSmithKline is dated in 1995, it has been in use in Europe since 1993.
According to the U.S. Centers for Disease Control and Prevention the following people should be vaccinated: all children over one year of age, people whose sexual activity puts them at risk, people with chronic liver disease, people who are being treated with clotting factor concentrates, people working within close proximity to the virus, and people who are living in communities where an outbreak is present. Hepatitis A is the most common vaccine-preventable virus acquired during travel, so people travelling to places where the virus is common like the Indian Subcontinent, Africa, Central America, South America, the far East, and Eastern Europe should also be vaccinated.
The vaccine should be given in the muscle of the upper arm and be given in two doses for the best protection. The initial dose of the vaccine should be followed up by a booster six to twelve months later. Protection against Hepatitis A begins approximately two to four weeks after the initial vaccination. Protection is proven to last at least 10 years and is estimated to last 21 to 27 years if the full course is administered.
Hepatitis A
Hepatitis A is an acute infectious disease of the liver caused by the hepatitis A virus , an RNA virus, usually spread the fecal-oral route; transmitted person-to-person by ingestion of contaminated food or water or through direct contact with an infectious person...
virus. The first successful vaccine against it was invented by Maurice Hilleman
Maurice Hilleman
Maurice Ralph Hilleman was an American microbiologist who specialized in vaccinology and developed over three dozen vaccines, more than any other scientist...
at Merck
Merck & Co.
Merck & Co., Inc. , also known as Merck Sharp & Dohme or MSD outside the United States and Canada, is one of the largest pharmaceutical companies in the world. The Merck headquarters is located in Whitehouse Station, New Jersey, an unincorporated area in Readington Township...
. The vaccine protects against the virus in more than 95% of cases and provides protection from the virus for at least ten years. The vaccine contains inactivated Hepatitis A virus which stimulates active immunity against a future infection.
The vaccine was first phased in around 1996 for children living in high-risk areas. In 1999, it was spread to areas with elevating levels of infection. Today, in the U.S., the vaccine is strongly recommended for all children 12 to 23 months of age in an attempt to eradicate the virus nationwide. The original FDA license for Havrix by GlaxoSmithKline is dated in 1995, it has been in use in Europe since 1993.
According to the U.S. Centers for Disease Control and Prevention the following people should be vaccinated: all children over one year of age, people whose sexual activity puts them at risk, people with chronic liver disease, people who are being treated with clotting factor concentrates, people working within close proximity to the virus, and people who are living in communities where an outbreak is present. Hepatitis A is the most common vaccine-preventable virus acquired during travel, so people travelling to places where the virus is common like the Indian Subcontinent, Africa, Central America, South America, the far East, and Eastern Europe should also be vaccinated.
The vaccine should be given in the muscle of the upper arm and be given in two doses for the best protection. The initial dose of the vaccine should be followed up by a booster six to twelve months later. Protection against Hepatitis A begins approximately two to four weeks after the initial vaccination. Protection is proven to last at least 10 years and is estimated to last 21 to 27 years if the full course is administered.
Commercial vaccines
This may not be a comprehensive list of all commercial Hepatitis A vaccines available. Please note that the definition of "U" (units) may vary between manufacturers depending on what test they use to measure Hepatitis A antigen in their products.- Avaxim: made by Sanofi PasteurSanofi pasteurSanofi Pasteur is the vaccines division of sanofi-aventis Group. It is the largest company in the world devoted entirely to vaccines.- History :...
. Inactivated Hepatitis A virus produced in MRC-5 cells. Each dose contains 160 U of antigen adsorbed on aluminium hydroxideAluminium hydroxideAluminium hydroxide, Al3, ATH, sometimes erroneously called Hydrate of alumina, is found in nature as the mineral gibbsite and its three, much more rare forms, polymorphs: bayerite, doyleite and nordstrandite. Closely related are aluminium oxide hydroxide, AlO, and aluminium oxide, Al2O3,...
(0.3 mg Al). - Epaxal: made by CrucellCrucellCrucell is a biotechnology company specializing in vaccines and antibodies. The firm, a subsidiary of Johnson & Johnson, is headquartered in Leiden, Netherlands...
. Also sold under the brand names HAVpur® and VIROHEP-A. This vaccine consists of virosomes, artificial particles composed of synthetic lipids and influenzaInfluenzaInfluenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...
proteins in addition to the Hepatitis A antigen. It does not contain aluminiumAluminiumAluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
. - Havrix: made by GlaxoSmithKlineGlaxoSmithKlineGlaxoSmithKline plc is a global pharmaceutical, biologics, vaccines and consumer healthcare company headquartered in London, United Kingdom...
. Inactivated Hepatitis A virus produced in MRC-5 cells. Each adult dose contains 1440 ELISAELISAEnzyme-linked immunosorbent assay , is a popular format of a "wet-lab" type analytic biochemistry assay that uses one sub-type of heterogeneous, solid-phase enzyme immunoassay to detect the presence of a substance in a liquid sample."Wet lab" analytic biochemistry assays involves detection of an...
units of viral antigen adsorbed on aluminium hydroxideAluminium hydroxideAluminium hydroxide, Al3, ATH, sometimes erroneously called Hydrate of alumina, is found in nature as the mineral gibbsite and its three, much more rare forms, polymorphs: bayerite, doyleite and nordstrandite. Closely related are aluminium oxide hydroxide, AlO, and aluminium oxide, Al2O3,...
(0.5 mg Al). The pediatric (child) doses contain half the amount of viral antigen and aluminium. - Vaqta: made by MerckMerckMerck may refer to:* Merck KGaA, , a German-based chemical and pharmaceutical company.** Merck Serono , the pharmaceutical division of Merck KGaA...
. Inactivated Hepatitis A virus produced in MRC-5 cells. An adult dose contains 50 U of antigen adsorbed onto 0.45 mg of aluminium (as aluminium hydroxyphosphate sulfate); a child dose contains half the amounts of antigen and aluminium.
See also
- TwinrixTwinrixTwinrix is a vaccine against hepatitis A and hepatitis B, manufactured by GlaxoSmithKline. Twinrix is administered over three doses.The name was created because it is a mixture of two earlier vaccines - Havrix, an inactivated-virus Hepatitis A vaccine, and ENGERIX-B, a recombinant Hepatitis B...