What is hepatitis A?
Hepatitis A is an acute form of liver inflammation that is often referred to as travel hepatitis. This is due to the fact that many sufferers catch the infection while traveling to countries with poor hygienic conditions. These include, above all, subtropical and tropical regions such as southern and southeastern Europe, Africa, Asia, and South and Central America. Infection occurs mainly through contaminated water (also in the form of ice cubes) and contaminated food.
In the industrialized countries of Europe and North America, however, there has been a sharp decline in hepatitis A infections in recent decades due to the high standard of hygiene.
Even heat up to a maximum of 85° Celsius or cold down to minus 15° Celsius does not bother the pathogen. On top of that, the hepatitis A virus is highly variable. It is therefore quite easily able to evade the protective mechanisms of the human immune system by means of small changes and adaptations.
Caution: the hepatitis A virus also remains infectious on the hands for several hours.
What are the symptoms of hepatitis A?
Especially in children, hepatitis A infections usually proceed without symptoms. The disease usually goes unnoticed in them and heals on its own. Experts assume that about 30 percent of adults in western industrialized countries are immune to hepatitis A because they experienced an asymptomatic infection, i.e. an infection without symptoms, during childhood.
Initially, hepatitis A usually presents with nonspecific symptoms, for example:
- Slight increase in temperature to less than 38° Celsius
- Loss of appetite
- Nausea and vomiting
- Performance slump
- Pressure pain in the right upper abdomen
Doctors refer to this phase of early symptoms as the prodromal phase. It lasts about two weeks.
In about one third of those affected, the prodromal phase is followed by the so-called icteric phase. The term is derived from the medical term for jaundice (icterus). In those affected, the skin and the white part of the eyes (sclerae) turn yellow. This is due to the fact that a breakdown product of the red blood pigment (bilirubin) is released by the liver damage and is deposited in the skin and sclerae.
The jaundice phase lasts from a few days to several weeks. It is much less common in children under six than in adults.
How is hepatitis A transmitted?
Hepatitis A viruses are mainly transmitted fecal-orally through smear infections: Infected people excrete the viruses largely in their stool, as early as one to two weeks before the first symptoms appear. If people do not wash their hands thoroughly after defecating, they transfer the viruses to doorknobs, cutlery or towels, for example. From there, they get onto the hands of healthy people and enter the body through the mucous membrane when they touch the mouth.
Occasionally, hepatitis A transmission occurs via blood and blood products. In this way, drug addicts also infect each other, for example when they share injecting equipment.
In pregnant women who become infected with hepatitis A, there is a possibility that the infection will pass to the unborn child.
Duration of infectivity
Those infected with hepatitis A are contagious as long as they excrete pathogens in their stool. The highest risk of infection for healthy people is one to two weeks before as well as in the first days after jaundice or elevation of liver values (transaminases). Presumably, most affected individuals are no longer contagious about one week after symptom onset.
Caution: Infected children excrete hepatitis A viruses in their stool for a significantly longer period than adults, possibly for several weeks.
Hepatitis A: incubation period
Examinations and diagnosis
For a hepatitis A diagnosis, a blood draw is important in addition to the medical history and physical examination. Elevated liver values, including GOT, GPT, gamma-GT and AP, indicate liver inflammation.
The body also produces specific antibodies against the hepatitis A viruses (HAV), which are detectable in the blood. Depending on the stage of infection, the immune system produces different classes of antibodies. The exact type of antibodies therefore indicates how long ago the infection occurred. For example, IgM antibodies againstHAV (anti-HAV IgM) indicate a fresh infection: they are detectable as early as two weeks after infection and for about three to four months.
Obligation to report
Hepatitis A is notifiable. This means that the attending physician must report all suspected cases and proven illnesses by name to the responsible public health department. The same applies to deaths from hepatitis A. The health office forwards the data to the Robert Koch Institute, where they are recorded statistically.
Treatment
There are no specific drugs against hepatitis A viruses. Therefore, in the case of hepatitis A, only symptomatic treatment is possible. For example, symptoms such as nausea or fever can be alleviated with appropriate medication if necessary. In addition, those affected should take it easy on themselves physically and eat only light food. High-carbohydrate, low-fat foods are particularly suitable for relieving the burden on the liver.
Hepatitis A therapy is generally administered at home and does not require hospitalization. Up to two weeks after the onset of the first symptoms or one week after the onset of jaundice, affected persons should have as little or no contact with healthy persons as possible. Consistent hand hygiene and a separate toilet help to reduce the risk of infection for family members.
If necessary, it is advisable for relatives to be vaccinated against hepatitis A as a precaution. In certain cases, it makes sense to administer ready-made antibodies against hepatitis A viruses (passive immunization) at the same time. In contrast to active immunization, in which the body must first produce the antibodies itself, these take effect immediately. However, if there has been previous contact with the virus, neither immunization is able to prevent disease in all cases.
Course of the disease and prognosis
In adults, hepatitis A infection is generally more severe than in children. However, very severe courses with acute liver failure or severely impaired liver function are rare. Such fulminant hepatitis usually affects older people over the age of 50. A severe course is also favored by: alcohol consumption, pre-existing liver diseases or medication damage.
A possible complication is hepatic decay coma. This sometimes occurs when many liver cells die during a severe course of hepatitis. In response to the toxins released by the decaying liver cells, the affected person loses consciousness. In this case, treatment as quickly as possible is important; liver transplantation may be necessary.
How long sick leave is required for hepatitis A depends on the individual course and cannot be said in general terms.
Prevention
In addition to conscious handling of food and water (especially when traveling) and thorough hand hygiene when dealing with infected persons, the best protection against hepatitis A is vaccination. Vaccination against hepatitis A is generally well tolerated. Possible side effects include fatigue, headache, limb pain, or redness. They usually disappear again quickly. There are also vaccines that protect against hepatitis A and hepatitis B viruses at the same time.
Find out here for whom the vaccination against hepatitis A is useful, how many booster vaccinations are necessary at what intervals (vaccination schedule) and who bears the costs for the vaccinations.
You can read everything important about the vaccination against hepatitis A in the article Hepatitis vaccination.
