Hepatitis A: Causes, Symptoms, Transmission, Treatment and Prevention

Hepatitis A is an inflammation of the liver caused by the hepatitis A virus (HAV). The virus is primarily spread when an uninfected (and unvaccinated) person ingests food or liquids contaminated with the feces of an infected person. The disease is closely associated with poor sanitary conditions and oral-anal sex.

Unlike hepatitis B and C, hepatitis A does not cause chronic liver disease, but it can cause debilitating symptoms and, rarely, fulminant hepatitis (acute liver failure), which is often fatal.

Hepatitis A occurs sporadically and in epidemics worldwide, with a tendency for cyclical recurrence. Hepatitis A viruses persist in the environment, being resistant to common food preservation methods. The virus is relatively stable at low pH levels and moderate temperatures, but it can be inactivated by high temperatures (>85°C) or chlorine.

According to data from the European surveillance system, children aged between 5 and 14 are the most affected, and most cases are reported in the months of September and October.

Mode of transmission

The hepatitis A virus is transmitted mainly through the fecal-oral route, which means when an uninfected person ingests food or water that has been contaminated with the feces of an infected person. In families, this can happen through dirty hands when an infected person prepares food for family members. Waterborne outbreaks, although rare, are usually associated with water contaminated by sewage or inadequately treated.

The virus can also be transmitted through close physical contact (such as oral-anal sex) with an infected person, although casual contact between people does not spread the virus.

Once transmitted, the virus spreads through the bloodstream to the liver, where it causes inflammation and swelling.

Symptoms

The incubation period for hepatitis A is usually 14–28 days. Signs and symptoms of hepatitis A usually do not appear until a few weeks after the virus has been contracted.

Most adults with hepatitis A have symptoms, including:

• fever
• yellow skin or eyes (jaundice)
• fatigue
• stomach pain,
• loss of appetite
• anorexia
• nausea
• abdominal discomfort
• dark-colored urine (dark yellow-brown)

Symptoms disappear within two months of infection. Most children under the age of 6 are asymptomatic, but they are highly contagious and can spread the infection easily.

These symptoms can be relatively mild and go away in a few weeks. Sometimes, however, hepatitis A infection leads to a severe illness that lasts for several months.

Severe complications are more common in older age groups. Infected children under the age of 6 usually do not show noticeable symptoms, and only 10% of them develop jaundice. Hepatitis A sometimes relapses, meaning the person who has just recovered gets sick again with another acute episode.

Diagnosis

Cases of hepatitis A are not clinically distinguishable from other types of acute viral hepatitis. Some people have only a few symptoms and show no signs of jaundice. Without visible signs of jaundice, it is difficult to diagnose any form of hepatitis through a physical examination. When symptoms are minimal, hepatitis A may remain undiagnosed.

Specific diagnosis is made by detecting HAV-specific immunoglobulin (IgM) antibodies in the blood. Additional tests include reverse transcription polymerase chain reaction (RT-PCR) to detect the hepatitis A virus RNA.

Treatment

There is no official cure for hepatitis A. Because it is a short-term viral infection that goes away on its own, treatment usually focuses on reducing symptoms.

After a few weeks of rest, hepatitis A symptoms usually begin to improve. To ease your symptoms, you should:

• avoid alcohol
• maintain a balanced diet
• drink plenty of fluids
• limit the use of over-the-counter medications

Prevention

The most effective way to prevent hepatitis A is through vaccination. This vaccine is given in a series of two doses, 6 to 12 months apart.

If you are traveling to a country where hepatitis A transmission is more common, get vaccinated at least 2 weeks before travel. Usually, it takes 2 weeks from the first dose for the body to start developing antibodies against hepatitis A.

To limit your chances of contracting hepatitis A, you should:

• wash your hands thoroughly, with soap and warm water, before eating or drinking and after using the toilet
• consume only bottled water
• consume products only from restaurants that follow proper sanitary standards, and not from street vendors

avoid eating peeled or raw fruits and vegetables in an area with low sanitary or hygiene standards

References
https://www.nfid.org/infectious-diseases/hepatitis/
https://www.who.int/news-room/fact-sheets/detail/hepatitis-a
https://www.mayoclinic.org/diseases-conditions/hepatitis-a/symptoms-causes/syc-20367007
https://www.healthline.com/health/hepatitis-a
https://www.cnscbt.ro/index.php/metodologii/hepatita-virala-a/534-metodologie-de-supraveghere-hepatita-virala-a/file
https://cnscbt.ro/index.php/metodologii/hepatita-virala-a/1214-2019-ghidului-de-identificare-a-comunitatilor-la-risc-de-imbolnavire-cu-hepatita-virala-10-09-2019/file
https://www.medlife.ro/glosar-medical/afectiuni-medicale/hepatita-a-cauze-simptome-tratament