Hepatitis Vaccines

Abstract

Viral hepatitis is a serious health problem all over the world. However, the reduction of the morbidity and mortality due to vaccinations against hepatitis A and hepatitis B has been a major component in the overall reduction in vaccine preventable diseases. We will discuss the epidemiology, vaccine development, and post-vaccination effects of the hepatitis A and B virus. In addition, we discuss attempts to provide hepatitis D vaccine for the 350 million individuals infected with hepatitis B globally. Given the lack of a hepatitis C vaccine, the many challenges facing the production of a hepatitis C vaccine will be shown, along with current and former vaccination trials. As there is no current FDA-approved hepatitis E vaccine, we will present vaccination data that is available in the rest of the world. Finally, we will discuss the existing challenges and questions facing future endeavors for each of the hepatitis viruses, with efforts continuing to focus on dramatically reducing the morbidity and mortality associated with these serious infections of the liver.

Antibodies against Hepatitis A and Hepatitis B Virus in Intravenous Immunoglobulin Products

“…Hepatitis A virus (HAV) infection is a self-limiting disease and asymptomatic in approximately 70% of children aged < 6 years, but it can result in a serious illness with risks of morbidity and mortality, particularly among susceptible older adults (12). HAV is transmitted primarily through person-to-person contact via the fecal-oral route or through the ingestion of contaminated food or water (23).…”

“…HAV is transmitted primarily through person-to-person contact via the fecal-oral route or through the ingestion of contaminated food or water (23). Therefore, the incidence and prevalence of HAV infection are influenced by general hygiene and the socioeconomic status of countries (345).…”

Impact of the mandatory Hepatitis A immunization program: before and after the vaccine in Ankara, Central of Turkey

“…All inactivated hepatitis A vaccines, which are approved for use in children and do not have a predominance in terms of efficacy and side effects, are also available in our country. 14,23 In Turkey, Hepatitis A seroprevelance studies have been performed in some groups and regions before, but we believe this study is important as it is the first observational-descriptive study comparing the pre-and post-vaccination period. 2,3,24 Seroprevalence studies are of vital importance, because HAV notifications may underestimate the true incidence especially in young children due to asymptomatic illness.…”

“…But ACIP expanded its recommendations in 1999, and the recommendations changed to the immunization of all children at one year of age in the United States in 2006. 14 Finally, the World Health Organization recommends that HAV vaccination should be included into the national immunization schedules for children aged ≥ 1 year on the basis of acute HAV incidence, shift in endemicity (from high to intermediate), and also consideration of cost effectiveness. 4 Following this strong recommendation, HAV vaccination programmes have been introduced and have reduced the incidence of HAV infection in many countries.…”

“Hep C, where art thou”: What are the remaining (fundable) questions in hepatitis C virus research?

“…Vaccine development is fundamental to globally eliminate HCV infection through prevention, representing a public health priority, but efforts have been repeatedly undermined by the considerable heterogeneity of the viral genome and lack of a readily available, immunocompetent small animal model . Prevention of HCV with vaccination would be most impactful in at‐risk populations not only PWID, but also from nosocomial infections (e.g., dialysis patients) . Vaccination‐induced antibody responses to HCV envelope glycoproteins E1/E2 alone are unlikely to provide sufficient protection against HCV infection .…”