Hepatitis A is an infectious disease of the liver caused by the hepatitis A virus (HAV). It is a common disease globally, with an estimated incidence of 1.5 million cases annually. HAV infection can be transmitted by eating food or drinking water contaminated with infected feces or by direct contact with infected people. Hepatitis A is considered a self-limiting disease, but can cause complications in severe forms.
Hepatitis A is widespread worldwide, with a higher incidence in areas with poor sanitation and in low- and middle-income countries. In industrialized countries, the prevalence of hepatitis A has decreased significantly due to the implementation of vaccination programs and hygiene standards. However, in low- and middle-income countries, where access to safe drinking water and sanitation is limited, hepatitis A remains a major public health problem. In these areas, the incidence of hepatitis A is higher in young children, but adults can also be affected.
HAV is a single-stranded RNA virus that multiplies in liver cells. HAV infection is initiated by eating food or drinking water contaminated with infected feces or by contact with infected people. The virus is present in infected stools and can remain infectious for several weeks in the environment. Once the virus reaches the intestine, it is absorbed by liver cells, where it multiplies and can cause liver damage. In general, the incubation period for hepatitis A is about 28 days.
Symptoms of hepatitis A range from asymptomatic to severe forms. In mild and moderate forms, symptoms include fever, nausea, vomiting, diarrhea, fatigue, muscle aches and abdominal pain. In severe forms, symptoms include jaundice, liver pain, liver failure and sometimes hepatic encephalopathy. Severe forms of hepatitis A are rare and occur more commonly in older adults or those with pre-existing liver disease.
Diagnosis and treatment
Hepatitis A is diagnosed by blood tests, which detect the presence of antibodies against HAV. In mild and moderate forms, treatment consists of bed rest, adequate hydration and avoidance of alcohol and hepatotoxic drugs. In severe forms, hospitalization and supportive treatment such as blood transfusions and medication may be required to prevent complications.
Hepatitis A is popularly known as “dirty hands disease” precisely because of its mode of transmission.
Inoculation with hepatitis A virus occurs through contact with any surface or object that has been contaminated.
Hepatitis A virus is the most common cause of acute viral hepatitis and mostly affects children and young adults.
It is estimated that, globally, more than half of the population comes into contact with hepatitis A virus at least once in their lifetime.
The route of transmission is predominantly fecal-oral, through faecalis contaminated food and water, so maintaining strict personal hygiene is the solution available to all to prevent infection.
Characteristics of hepatitis A
It is a mild form of hepatitis, which is curable in most patients
Hepatitis A vaccine is available
It does not become chronic or heal with sequelae
The patient can be naturally immunized: if at first, through interaction with different communities, there is an increased susceptibility to acquire the hepatitis A virus, over time, antibodies are formed that will protect us for life.
Once the virus has been inoculated into the body via digestive, sexual or blood routes, it takes time to incubate.
The patient will have non-specific digestive symptoms, such as diarrhea, abdominal pain or altered states for which they cannot find an explanation.
Fever, headache, nausea, weight loss or pain in the right abdomen may also be signs of hepatitis A.
Although jaundice, which is yellow discoloration of the skin and scrotum, is a marker of hepatitis, in its course, hepatitis A may not be accompanied by this sign.
During its viremia period, when the virus expresses its pathogenic potential, the disease is transmissible.
Usually, two weeks before diagnosis and one to two weeks after cure the virus can still be dangerous to others.
Diagnosis is made on the basis of blood tests, but epidemiological investigations can help.
Factors favoring hepatitis A virus infection such as integration into new communities and travel to high-risk areas can help determine when and how the inoculation occurred.
The recovery period for the patient lasts about one month, maximum two months and after that, the risks of relapse, sequelae or further complications are particularly low.
In the dental surgery, the risk of hepatitis A virus infection is low. Since dental instruments are sterilized after use and surfaces are regularly disinfected, the level of hygiene in these areas is much higher than in other public places.
Vaccination is the most effective way to prevent hepatitis A. The vaccine consists of a series of two injections, given at 6–12-month intervals.
The vaccine is recommended for people living or travelling in areas at high risk of hepatitis A, and for people with pre-existing liver disease or at high risk of exposure to the virus.
In addition, proper food and water hygiene can reduce the risk of HAV infection. It is important to wash hands with soap and warm water before preparing food and after using the toilet.
It is advisable to avoid drinking tap water and eating raw or undigested food in areas at high risk of hepatitis A.
The human body is constantly fighting against illness through its components.
Some illnesses can occur relatively quickly, through inoculation of viruses found everywhere, while others develop slowly, through malfunctioning of certain elements and structures of the body.
Any pathogen that enters the body triggers a series of defence reactions designed to neutralize and eliminate the foreign body.
A healthy body copes well with the challenges posed by these pathogens, whereas a low immune terrain means the onset and exacerbation of disease.
Hepatitis A is a common infectious liver disease that can be prevented by vaccination and proper food and water hygiene. HAV infection can be self-limiting but can cause complications in severe forms. It is important to diagnose and treat this disease in its early stages to prevent complications and protect patients’ health.