Hepatitis A

What is it?

Hepatitis A is an acute inflammatory disease of the liver. In most cases the patient recovers in weeks or months. Each year more than one million cases of hepatitis A virus infection are recorded worldwide. Hepatitis A does not cause chronic disease and is rarely fatal but can cause fulminant hepatitis (acute liver failure).

Causes of Hepatitis A

It is caused by infection with hepatitis A virus (VAH), which is a positive and uncovered single-stranded RNA virus of the genus Hepatovirus within the Picornaviridae family. There are several genotypes (from I to III) and subtypes (A and B) of the VAH in humans with a characteristic geographical distribution: in Europe type IA predominates.

The rate of VAH infection is different depending on the socio-economic level of the country: the high level of infection is typical of developing countries with poor hygienic conditions; the intermediate level occurs in countries where the infection affects adolescents and adults and large epidemic outbreaks may occur; the low level of VAH infection occurs in developed countries, usually in people traveling to areas of high infection rate, as well as in isolated communities and closed institutions (prisons, boarding schools, etc.).

Each year more than one million cases of hepatitis A virus infection are recorded worldwide.
Dr. Vicente Carreño

Pathways of Hepatitis A infection

Hepatitis A is transmitted mainly through the faecal-oral route, by ingesting contaminated wastewater and contaminated food such as vegetables, seafood, etc. VAH can also be transmitted by physical contact with an infected person, by transfusion of infected blood products and rarely from a pregnant woman to the fetus (vertical transmission).

Diagnosis of Hepatitis A

It can be diagnosed by analyzing liver enzymes (transaminases) and detecting antibodies to type A IgM and IgG, or RNA in faeces or blood. The majority of patients at the onset of symptoms present intense fatigue and jaundice (yellow coloration of the conjunctiva).

Prevention

VAH infection can be prevented by a very effective specific vaccine, which generates antibodies that protect against infection up to 100% of the people who receive it. The protection lasts at least 5-8 years and is likely to protect in the longer term. People traveling to countries with a high level of VAH infection should be vaccinated before traveling.

Treatment of Hepatitis A

There is no specific treatment for acute hepatitis A. There are dietary measures that must be applied, especially if there is jaundice.

If you are traveling to a country at risk, contact us beforehand because you may need to be vaccinated with Hepatitis A.

References

Carreño V, Castillo I (eds.). Hepatitis víricas: Biología, clínica y tratamiento. 1ª ed. Barcelona: Springer Verlag Ibérica. Parte II: Virus A de la hepatitis. 2001; p 89.
Reiss G, Keeffe EB. Review article: hepatitis vaccination in patients with chronic liver disease. Aliment Pharmacol Ther 2004;19:715-27.
Leung AK, et al. Hepatitis A: a preventable threat. Adv Ther 2005;22:578-86.
Vaughan G, et al. Hepatitis A virus: host interactions, molecular epidemiology and evolution. Infect Genet Evol 2014;21:227-43.
Liang TJ, Ghany MG. Therapy of hepatitis C-back to the future. N Engl J Med 2014;370:2043-7.
Carreño V. Review article: management of chronic hepatitis C in patients with contraindications to anti-viral therapy. Aliment Pharmacol Ther 2014;39:148-62.
Gane E, et al. Strategies to manage hepatitis C virus (HCV) infection disease burden – volume 2. J Viral Hepat 2015;22(Suppl.1):46-73.