Hepatitis A vaccines

Hepatitis A vaccine. Hepatitis A vaccine is recommended for use in selected states and regions, and for certain high-risk groups consult your local public health authority. See MMWR. l999 48(RR-l2) l-37. 

Individuals at high risk of acquiring hepatitis A (see Table 21-1) should receive either serum immune globulin or the hepatitis A vaccine, depending on their personal circumstances, as described below.1,5... 

Pre-exposure prophylaxis with IGIM is indicated for individuals at high risk of acquiring the HAV who cannot receive the hepatitis A vaccine (e.g., because of allergy to the components alum or 2-phenoxyethanol). Additionally, travelers who plan to depart for endemic areas within 2 weeks and have not yet received the hepatitis A vaccine should receive IGIM because active vaccine immunity takes several weeks to develop. 

Persons at risk of acquiring the HAV should receive the hepatitis A vaccine when appropriate. 

There is no benefit in administering the vaccine after a person has been exposed to the HAV. Two inactivated hepatitis A vaccines, Havrix and VAQTA, are available in the United States and are effective in providing active immunization. The major difference between the two vaccines is that HAVRIX contains 2-phenoxyethanol as a preservative whereas VAQTA is preservative-free.1 Either vaccine is effective in providing active pre-exposure prophylaxis when given in two injections 6 months apart (referred to as months 0 and 6). The two vaccines are considered interchangeable, and doses are dependent on age (Table 21-3). 

The hepatitis A vaccine may provide effective immunity for 8 years in adults and children. Additionally, kinetic models have theorized that immunity with the vaccine may be longer than 20 years, but this has not been confirmed in clinical trials.1... 

The most common adverse effects in adults include injection site reactions (e.g., tenderness, pain, and warmth), headaches within 5 days after vaccination, and fatigue. Local reactions may be minimized by using an appropriate needle length based on the person s age and size and by administering the injection intramuscularly in the deltoid muscle. Children may also have feeding disturbances. Hepatitis A vaccine given... 

TABLE 21-3. Recommended Intramuscular Doses of Hepatitis A Vaccines... 

Hepatitis A vaccine was licensed in the United States in 1995. It is an inactivated whole virus vaccine that is administered in a... 

Hepatitis A vaccine exemplifies vaccine preparations containing inactivated viral particles. It consists of a formaldehyde-inactivated preparation of the HM 175 strain of hepatitis A virus. Viral particles are normally propagated initially in human fibroblasts. 

In areas without existing hepatitis A vaccination programs, catch-up vaccination of children ages 2-18 years can be considered,... 

Heparitin sulfate, 4 706 Hepatitis A vaccine, 25 492-493 Hepatitis B vaccine, 25 491 from yeast, 26 487 Hepatitis B virus (HBV), 3 135 antiviral therapy, 3 154-159 infection process, 3 153-154 Hepatitis B virus detection, method for, 14 153-154... 

Examples of killed or inactivated vaccines are cholera vaccine containing dead strains of Vibrio cholerae, hepatitis A vaccine with inactivated hepatitis A virus, pertussis vaccine with killed strains of Bordetella pertussis, typhoid vaccine with killed Salmonella typhi, and influenza vaccine with various strains of inactivated influenza viruses (see Exhibit 4.2 for a discussion of influenza viruses and vaccines and Exhibit 4.3 on avian influenza H5N1). 

Immunopotentiating reconstituted influenza virosomes (IRTV) are spherical 150-nm sized particles consisting of a phospholipid bilayer in which influenza virus A/Singapore strain-derived hemagglutinin (HA) and neuraminidase (NA) are intercalated. As such, they resemble and mimic the influenza virus envelope. The difference from conventional liposome formulations lies in the inclusion of the viral envelope proteins HA and NA as well as viral phospholipids. Especially, the inclusion of influenza virus HA provides IRIV with delivery and immimogenic capacities. IRTV are licensed for human use as adjuvant in hepatitis A vaccination and as influenza subunit vaccine (1). 

IRIV adjuvance in hepatitis A vaccination has been demonstrated as enhancement of humoral responses (1). There are only few adjuvants licensed for human use and they predominantly enhance humoral immune responses (2-4). In view of chronic viral diseases, infections linked to intracellular pathogens, and cancer immunotherapy, there is a need for appropriate adjuvants that have the capability to enhance cellular immune responses, in particular cytotoxic T-cell (CTL) responses (4,5). Here, we addressed IRIV-elicited immune responses and IRIV capacity to enhance CTL responses. 

Hepatitis A vaccine (Havrix) Vaccine Inj 1 mL 1 mL IM folbwed by 1 mL IM 6-12 months later. 96% effective. For immediate protection, give immune globulin (0.02 mL/kg IM) simultaneously. 

Hepatitis A vaccine (Formaldehyde)-inactivated hepatitis A virus Active immunization against hepatitis A... 

Hepatitis A vaccination is indicated for active immunisation against hepatitis A virus (HAV) infection in subjects at risk of exposure to HAV such as travellers to high prevalence areas, armed force personnel travelling to high endemic areas, person in whom... 

Recently a new liposome-based hepatitis A vaccine (Epaxat), developed by the... 

Hepatitis A Immune globulin (intramuscular [IM]) Preexposure prophylaxis 0.02 mL/ kg IM for anticipated risk of s 3 months, 0.06 mL/kg for anticipated risk of > 3 months, repeated every 4-6 months for continued exposure. Preexposure and postexposure hepatitis A prophylaxis. The availability of hepatitis A vaccine has greatly reduced the need for preexposure prophylaxis. 

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