Hepatitis A (common-source hepatitis)
Summary/Definition
Viral hepatitis A falls under the law on infectious diseases of the second level in the Republic of Korea, as it is an acute liver disease.
Chain of transmission
In most cases, the infection is transmitted orally through the consumption of contaminated food and water. There is also a risk of mass distribution by blood transfusion, drug use through infected syringes, sexually, etc. In most cases, the infection is transmitted in families and among close relatives through the patient due to the use of contaminated products. There is also a risk of mass distribution in public places, for example, in military units with a dense contingent, orphanages and other institutions.
Pre-incubation period
The period of the highest risk of infection is 2 weeks before the onset of symptoms and 1 week after the appearance of “jaundice”. The greatest risk of infection occurs in the first 1-2 weeks after the onset of symptoms.
Symptoms
Latent period
Clinical symptoms usually appear 15-50 days after infection, on average about 28-30 days during the incubation period.
Clinical features
The clinical picture of viral hepatitis A includes fever, loss of appetite, nausea, vomiting, feeling weak, upset stomach, diarrhea and other symptoms characteristic of viral infections. Jaundice signs usually appear within a week after the onset of symptoms and may include yellowing of the sclera of the eyes and skin, darkening of urine, the appearance of itchy rashes and other characteristic signs. In most children under the age of 6, the disease proceeds without symptoms (in about 70% of cases), but about 10% of children may have signs of jaundice, and in some children, the risk of worsening symptoms increases with age. In the case of the disease in an acute form, often deadly, a fatal outcome is observed in 0.1-0.3% of infected people, and in people over 50 years of age this risk increases to 1.8%. In the absence of chronic infectious diseases, recovery usually occurs within a few weeks to several months. In approximately 15% of infected patients, the duration of hepatitis A disease is up to 1 year, while there is a possibility of relapse.
Diagnostics
Reliable diagnosis is carried out using the analysis of the target gene of the hepatitis A virus, using Anti-Hav-lgM (IgM class antibodies to hepatitis A virus) and PCR (polymerase chain reaction), as well as other procedures. The analysis for immunoglobulin M can be carried out 5-10 days before the onset of symptoms and up to 6 months after possible infection. Relapses of viral hepatitis A can occur and continue throughout life.
Treatment and course of the disease
Before the manifestation of jaundice, there is an increase in the level of serum liver enzyme, in which the level of AST in the blood test significantly exceeds the level of ALT. The level of bilirubin in the blood serum, which indicates the presence of jaundice, is usually much higher than normal, and there is also an increase in other indicators of the inflammatory process.
A therapeutic agent for the treatment of viral hepatitis A still exists. In general, treatment is aimed at symptomatic therapy to alleviate the manifestations of the disease. A diet with a high protein content helps to improve the condition of the liver, which is also facilitated by the observance of a rest regime. In the case of acute painful symptoms, inpatient treatment is often required to relieve pain.
Prevention and vaccination
Public health, taking into account the principles of hygiene
Special attention should be paid to such aspects as regular hand washing, ensuring the availability of clean water for drinking and sanitation, protecting drinking water sources from pollution, compliance with hygiene standards in food processing and the work of personnel in the food industry, as well as other factors.
Vaccination against hepatitis A
After the initial vaccination, after 6-12 months, it is necessary to carry out a second vaccination to ensure immunity for more than 20 years.
– Recommended for all children aged from 1 year to 1 year and 11 months.
– The risk group with weak immunity to hepatitis A (or none at all) includes children, adolescents and adults.
Groups at increased risk of hepatitis A infection include
People who often travel to high-risk regions or live there for a long time.
Homosexuals.
Persons abusing narcotic substances.
Workers at increased risk of contracting hepatitis A in the workplace.
Persons with blood clotting disorders.
Persons in close contact with patients with hepatitis A.
Complications
Among the complications associated with OSL in hepatitis A, Guillain-Barre syndrome, acute renal failure, cholecystitis, pancreatitis, vasculitis, arthritis, etc. may occur. It is important to note that 80% of patients with OS are at increased risk of death, especially in the case of fulminant liver failure.