Incubation period for hepatitis A
The incubation period is the time between infection with the pathogen and the appearance of the first symptoms. This is about 2-6 weeks for the hepatitis A virus. The incubation period is followed by the prodromal stage.
The prodromal stage is the period of time in which signs or early signs of symptoms occur, which are typical but rather unspecific for the disease and may also be an indication of other diseases. This may be followed by the icteric stage, which is characterized by the yellow coloration of the sclera of the eyes and skin. The classic course of the disease (after incubation period) lasts 2-4 weeks, in rare cases it takes 3-4 months until complete healing.
After infection, the hepatitis A virus multiplies in the human body for about one to two weeks. During this still asymptomatic phase, the virus can already be excreted in the stool and transmitted to other people. The immune defence becomes active.
This can lead to the destruction of liver cell tissue and the classic picture of inflammation of the liver (hepatitis). Accompanied by an icterus (yellowing of the skin). Meanwhile, the immune system produces antibodies, which will provide lifelong immunological protection. In 25% of cases, the infection can proceed completely without symptoms. In children, the disease usually runs clinically silent.
Symptoms of Hepatitis A
The early symptoms (prodromies) of hepatitis A infection are very unspecific and can be confused with flu. Those affected feel severely weakened, get fever, diarrhea accompanied by nausea, vomiting and a feeling of fullness. After a few days, specific symptoms may occur, which may indicate that the liver is affected.
Like the yellowish/brownish discoloration of the skin and sclera of the eyes – known in technical jargon as icterus/icteric stage. The stool may change to a lighter color than usual, while the urine may be darker because the bile dyes that are normally discharged with the stool via the bile are released into the blood. Although these symptoms are typical of hepatitis A, they are not obligatory.
Pain in the right upper abdomen and sensitivity to pressure on the liver may occur. In adults, hepatitis A can be completely symptom-free in 25% of cases. The higher the age of the patient at initial infection, the more severe the symptoms.
In Germany, only 5% of people under 50 years of age are infected, while the population over 50 years of age is immunized in up to 90% of cases. The reason is the lower hygiene standards of earlier times, so that many older people became infected with the hepatitis A virus in childhood. In Germany, about 50 percent of those infected with hepatitis A are tourists from southern travel countries. The rest are infections in community facilities, such as kindergartens. But also in Germany, imported hepatitis A infections repeatedly cause minor local outbreaks (epidemics).The viruses are either brought to the kindergarten or passed on to food by infected employees in companies such as butcher shops and bakeries.
