What are the key facts about Hepatitis A. How is Hepatitis A transmitted. What are the symptoms and complications of Hepatitis A. How is Hepatitis A diagnosed and treated. Can Hepatitis A be prevented through vaccination. What are the global trends and geographic distribution of Hepatitis A.

Key Facts About Hepatitis A: Understanding the Viral Liver Infection

Hepatitis A is a viral infection that causes inflammation of the liver. This highly contagious disease is caused by the hepatitis A virus (HAV) and primarily spreads through contaminated food and water or close contact with infected individuals. While it can cause mild to severe illness, most people recover fully with lifelong immunity.

Here are some essential facts about hepatitis A:

• It is primarily transmitted through the fecal-oral route
• Poor sanitation and hygiene increase the risk of infection
• Symptoms can range from mild to severe
• A safe and effective vaccine is available for prevention
• Most people recover completely, but rare cases can be fatal

How does hepatitis A differ from other types of viral hepatitis?

Unlike hepatitis B and C, hepatitis A does not lead to chronic liver disease. However, it can cause debilitating symptoms and, in rare cases, acute liver failure (fulminant hepatitis), which can be fatal. According to World Health Organization estimates, approximately 7,134 people died from hepatitis A worldwide in 2016, accounting for 0.5% of all viral hepatitis-related deaths.

Transmission and Risk Factors: How Hepatitis A Spreads

Understanding the transmission routes and risk factors associated with hepatitis A is crucial for prevention. The virus primarily spreads through the fecal-oral route, meaning that contaminated feces from an infected person enters the mouth of an uninfected individual.

Common modes of transmission include:

• Consuming contaminated food or water
• Close personal contact with an infected person
• Sexual contact, particularly oral-anal sex
• International travel to areas with high hepatitis A prevalence

Risk factors that increase the likelihood of hepatitis A infection include:

1. Poor sanitation and hygiene practices
2. Lack of access to safe drinking water
3. Living in or traveling to areas with high hepatitis A prevalence
4. Being a man who has sex with men (MSM)
5. Using illicit drugs
6. Working with primates or with the hepatitis A virus in research laboratories

Can hepatitis A be transmitted through casual contact?

Hepatitis A is not typically spread through casual contact such as handshakes or hugs. However, the virus can survive on surfaces for extended periods, making proper hand hygiene crucial in preventing transmission. Washing hands thoroughly with soap and water, especially after using the bathroom and before preparing or eating food, is an effective way to reduce the risk of infection.

Symptoms and Complications: Recognizing Hepatitis A

The symptoms of hepatitis A can vary widely, from mild and barely noticeable to severe and debilitating. Many infected individuals, especially young children, may not experience any symptoms at all. This asymptomatic nature can contribute to the spread of the virus, as infected individuals may unknowingly transmit it to others.

Common symptoms of hepatitis A include:

• Fever
• Fatigue
• Loss of appetite
• Nausea and vomiting
• Abdominal pain
• Dark urine
• Clay-colored stools
• Joint pain
• Jaundice (yellowing of the skin and eyes)

How long does it take for symptoms to appear after infection?

The incubation period for hepatitis A typically ranges from 14 to 28 days, with an average of about 4 weeks. During this time, infected individuals may not show any symptoms but can still be contagious. Symptoms usually last for several weeks, although some people may experience prolonged or relapsing symptoms for up to 6 months.

While most people recover completely from hepatitis A, in rare cases, complications can occur. These may include:

• Cholestatic hepatitis (a severe form with prolonged jaundice and itching)
• Relapsing hepatitis (symptoms return over a 6-9 month period)
• Fulminant hepatitis (acute liver failure, which can be life-threatening)

Diagnosis and Treatment: Managing Hepatitis A Infection

Diagnosing hepatitis A involves a combination of clinical evaluation, laboratory tests, and consideration of potential exposure risks. Healthcare providers typically begin by assessing symptoms and medical history, followed by specific diagnostic tests to confirm the presence of the virus.

How is hepatitis A diagnosed?

The primary method for diagnosing hepatitis A is through blood tests. These tests look for specific antibodies produced by the immune system in response to the hepatitis A virus. The two main types of antibodies detected are:

• IgM anti-HAV: Indicates a current or recent infection
• Total anti-HAV: Shows past infection or vaccination

In addition to antibody tests, healthcare providers may also order liver function tests to assess the extent of liver damage. These tests measure levels of enzymes and proteins that indicate liver health, such as:

• Alanine aminotransferase (ALT)
• Aspartate aminotransferase (AST)
• Alkaline phosphatase (ALP)
• Bilirubin

What is the treatment for hepatitis A?

There is no specific antiviral treatment for hepatitis A. The infection is usually self-limiting, meaning it resolves on its own without medical intervention. Treatment primarily focuses on managing symptoms and supporting the body’s natural healing process. Key aspects of hepatitis A management include:

1. Rest and adequate hydration
2. Nutritional support
3. Avoiding alcohol and medications that may strain the liver
4. Monitoring for complications
5. In severe cases, hospitalization may be necessary for close observation and supportive care

While most people recover completely within a few months, it’s essential to follow up with healthcare providers to ensure proper liver function and recovery. In rare cases of fulminant hepatitis, liver transplantation may be considered as a life-saving measure.

Prevention and Vaccination: Protecting Against Hepatitis A

Preventing hepatitis A involves a combination of personal hygiene practices, public health measures, and vaccination. The hepatitis A vaccine is highly effective in preventing infection and has significantly reduced the incidence of the disease in many parts of the world.

How effective is the hepatitis A vaccine?

The hepatitis A vaccine is both safe and highly effective. Studies have shown that the vaccine is nearly 100% effective in preventing hepatitis A when given in a two-dose series. The vaccine stimulates the immune system to produce antibodies against the hepatitis A virus, providing long-lasting protection.

Key points about hepatitis A vaccination:

• Recommended for all children starting at age 12 months
• Given in two doses, typically 6 to 18 months apart
• Also recommended for adults at high risk of infection
• Provides protection for at least 20-25 years, possibly lifelong
• Can be given as a combination vaccine with hepatitis B for adults

Who should receive the hepatitis A vaccine?

The Centers for Disease Control and Prevention (CDC) recommends hepatitis A vaccination for:

• All children at age 12-23 months
• Unvaccinated children and adolescents aged 2-18 years
• International travelers
• Men who have sex with men
• People who use injection or non-injection drugs
• People with occupational risk of exposure
• People with chronic liver disease
• People with clotting factor disorders
• Household members and close contacts of adopted children from countries where hepatitis A is common

In addition to vaccination, other preventive measures include:

1. Practicing good hand hygiene
2. Ensuring safe food and water consumption, especially when traveling
3. Avoiding raw or undercooked shellfish
4. Practicing safe sex

Global Trends and Geographic Distribution: Hepatitis A Worldwide

The prevalence and incidence of hepatitis A vary significantly across different regions of the world. Understanding these global trends and geographic distribution patterns is crucial for implementing effective prevention and control strategies.

How does hepatitis A prevalence differ in various parts of the world?

Hepatitis A prevalence can be categorized into three levels:

• High endemicity: Common in low- and middle-income countries with poor sanitation and hygiene. In these areas, most children are infected by age 10, often without symptoms.
• Intermediate endemicity: Seen in countries with improving sanitation and hygiene. Infections occur in older children and adults, with more symptomatic cases.
• Low endemicity: Typical in high-income countries with good sanitation and hygiene. Outbreaks may occur in high-risk groups or through contaminated food sources.

Factors influencing geographic distribution include:

1. Socioeconomic conditions
2. Access to clean water and sanitation
3. Vaccination programs
4. Population density and living conditions
5. Food safety practices

Epidemiology and Outbreaks: Understanding Hepatitis A Spread

Hepatitis A occurs both sporadically and in epidemics worldwide, with a tendency for cyclic recurrences. The epidemiology of the disease is complex and can vary significantly between different regions and populations.

What factors contribute to hepatitis A outbreaks?

Several factors can contribute to hepatitis A outbreaks:

• Contaminated food or water sources
• Poor sanitation and hygiene practices
• High-risk behaviors in certain populations
• Low vaccination rates in susceptible communities
• International travel and globalization of food supply

Notable hepatitis A outbreaks have occurred globally, demonstrating the potential for rapid spread and significant public health impact. For example:

1. The 1988 Shanghai outbreak affected approximately 300,000 people, linked to consumption of contaminated clams.
2. Recent outbreaks in the United States have been associated with person-to-person transmission among people who use drugs and people experiencing homelessness.
3. Foodborne outbreaks have been linked to imported produce, highlighting the need for global food safety measures.

Research and Future Directions: Advancing Hepatitis A Prevention and Control

Ongoing research in hepatitis A focuses on improving prevention strategies, enhancing diagnostic techniques, and developing potential treatments. These efforts aim to reduce the global burden of the disease and improve outcomes for affected individuals.

What are the current areas of research in hepatitis A?

Key areas of hepatitis A research include:

• Development of more effective and longer-lasting vaccines
• Improving diagnostic tests for rapid and accurate detection
• Understanding the molecular biology of the hepatitis A virus
• Investigating potential antiviral treatments
• Studying the long-term effects of hepatitis A infection
• Evaluating the impact of vaccination programs on disease epidemiology

Future directions in hepatitis A prevention and control may involve:

1. Expanding global vaccination coverage
2. Implementing innovative public health strategies in high-risk areas
3. Developing novel therapies for severe cases
4. Enhancing surveillance systems for early outbreak detection
5. Addressing the impact of climate change on waterborne disease transmission

As research progresses, our understanding of hepatitis A continues to evolve, leading to improved strategies for prevention, diagnosis, and management of this important public health concern.

Hepatitis A

Hepatitis A

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• Hepatitis A

Key facts

• Hepatitis A is an inflammation of the liver that can cause mild to severe illness.
• The hepatitis A virus (HAV) is transmitted through ingestion of contaminated food and water or through direct contact with an infectious person.
• Almost everyone recovers fully from hepatitis A with a lifelong immunity. However, a very small proportion of people infected with hepatitis A could die from fulminant hepatitis.
• The risk of hepatitis A infection is associated with a lack of safe water and poor sanitation and hygiene (such as contaminated and dirty hands).
• A safe and effective vaccine is available to prevent hepatitis A.

Overview

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 water that is contaminated with the faeces of an infected person. The disease is closely associated with unsafe water or food, inadequate sanitation, poor personal hygiene 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. WHO estimates that in 2016, 7134 persons died from hepatitis A worldwide (accounting for 0.5% of the mortality due to viral hepatitis).

Hepatitis A occurs sporadically and in epidemics worldwide, with a tendency for cyclic recurrences. Epidemics related to contaminated food or water can erupt explosively, such as the epidemic in Shanghai in 1988 that affected about 300 000 people (1). They can also be prolonged, affecting communities for months through person-to-person transmission. Hepatitis A viruses persist in the environment and can withstand food production processes routinely used to inactivate or control bacterial pathogens.

Geographical distribution

Geographical distribution areas can be characterized as having high, intermediate or low levels of hepatitis A virus infection. However, infection does not always mean disease because infected young children do not experience any noticeable symptoms.

Infection is common in low- and middle-income countries with poor sanitary conditions and hygienic practices, and most children (90%) have been infected with the hepatitis A virus before the age of 10 years, most often without symptoms (2). Infection rates are low in high-income countries with good sanitary and hygienic conditions. Disease may occur among adolescents and adults in high-risk groups, such as persons who inject drugs (PWID), men who have sex with men (MSM), people travelling to areas of high endemicity and in isolated populations, such as closed religious groups. In the United States of America, large outbreaks have been reported among persons experiencing homelessness. In middle-income countries and regions where sanitary conditions are variable, children often escape infection in early childhood and reach adulthood without immunity.

Transmission

The hepatitis A virus is transmitted primarily by the faecal-oral route; that is when an uninfected person ingests food or water that has been contaminated with the faeces of an infected person. In families, this may happen though dirty hands when an infected person prepares food for family members. Waterborne outbreaks, though infrequent, are usually associated with sewage-contaminated or inadequately treated water.

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

Symptoms

The incubation period of hepatitis A is usually 14–28 days.

Symptoms of hepatitis A range from mild to severe and can include fever, malaise, loss of appetite, diarrhoea, nausea, abdominal discomfort, dark-coloured urine and jaundice (a yellowing of the eyes and skin). Not everyone who is infected will have all the symptoms.

Adults have signs and symptoms of illness more often than children. The severity of disease and fatal outcomes are higher in older age groups. Infected children under 6 years of age do not usually experience noticeable symptoms, and only 10% develop jaundice. Hepatitis A sometimes relapses, meaning the person who just recovered falls sick again with another acute episode. This is normally followed by recovery.

Who is at risk?

Anyone who has not been vaccinated or previously infected can get infected with the hepatitis A virus. In areas where the virus is widespread (high endemicity), most hepatitis A infections occur during early childhood. Risk factors include:

• poor sanitation;
• lack of safe water;
• living in a household with an infected person;
• being a sexual partner of someone with acute hepatitis A infection;
• use of recreational drugs;
• sex between men; and
• travelling to areas of high endemicity without being immunized.

Diagnosis

Cases of hepatitis A are not clinically distinguishable from other types of acute viral hepatitis. Specific diagnosis is made by the detection of HAV-specific immunoglobulin G (IgM) antibodies in the blood. Additional tests include reverse transcriptase polymerase chain reaction (RT-PCR) to detect the hepatitis A virus RNA and may require specialized laboratory facilities.

Treatment

There is no specific treatment for hepatitis A. Recovery from symptoms following infection may be slow and can take several weeks or months. It is important to avoid unnecessary medications that can adversely affect the liver, e.g. acetaminophen, paracetamol.

Hospitalization is unnecessary in the absence of acute liver failure. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.

Prevention

Improved sanitation, food safety and immunization are the most effective ways to combat hepatitis A.

The spread of hepatitis A can be reduced by:

• adequate supplies of safe drinking water;
• proper disposal of sewage within communities; and
• personal hygiene practices such as regular handwashing before meals and after going to the bathroom.

Several injectable inactivated hepatitis A vaccines are available internationally. All provide similar protection from the virus and have comparable side effects. No vaccine is licensed for children younger than 1 year of age. In China, a live attenuated vaccine is also available.

WHO response

 

Global health sector strategies on, respectively, HIV, viral hepatitis, and sexually transmitted infections for the period 2022–2030 (GHSSs) guide the health sector in implementing strategically focused responses to achieve the goals of ending AIDS, viral hepatitis (especially chronic hepatitis B and C)  and sexually transmitted infections by 2030.

The GHSS recommend shared and disease-specific country actions supported by actions by WHO and partners. They consider the epidemiological, technological, and contextual shifts of previous years, foster learnings across the disease areas, and create opportunities to leverage innovations and new knowledge for effective responses to the diseases. They call to scale up prevention, testing and treatment of viral hepatitis with a focus to reach populations and communities most affected and at risk for each disease, as well as addressing gaps and inequities. They promote synergies under a universal health coverage and primary health care framework and contribute to achieving the goals of the 2030 Agenda for Sustainable Development.

WHO organizes annual World Hepatitis Day campaigns (as 1 of its 9 flagship annual health campaigns) to increase awareness and understanding of viral hepatitis. For World Hepatitis Day 2023, WHO focuses on the theme “One life, one liver” to illustrate the importance of the liver for a healthy life and the need to scale up viral hepatitis prevention, testing and treatment to prevent liver diseases and achieve the 2030 hepatitis elimination target.

 

Global hepatitis report, 2017

World Hepatitis Day

Global health sector strategy on viral hepatitis

 

 


Publications

• Financing prevention, testing and treatment of hepatitis in the context of Universal Health Coverage
• Guidelines for viral hepatitis planning and tracking progress towards elimination
• Immunological basis for immunization: hepatitis A
• The global prevalence of hepatitis A virus infection and susceptibility
• WHO position paper on hepatitis A vaccines
• More WHO publications

 

More about hepatitis

• WHO’s work on hepatitis
• Global Hepatitis Programme

 

 

Hepatitis A (Hep A) – Treatment

What is hepatitis?

Hepatitis is a general term for inflammation of the liver. Normally, the liver breaks down waste products in your blood. But when the liver is inflamed, it doesn’t do a good job of getting rid of waste products. This causes waste products to build up in your blood and tissues.

Many different things can cause hepatitis. The most common cause of hepatitis is infection with one of the 5 hepatitis viruses (A, B, C, D, or E). Lack of blood supply to the liver, poison, autoimmune disorders, excessive alcohol use, liver injury, and taking certain medicines can also cause hepatitis. Less commonly, viral infections such as mononucleosis or cytomegalovirus can cause hepatitis.

There are 2 main kinds of hepatitis: acute hepatitis and chronic hepatitis. Most people get over the acute hepatitis in a few days or weeks. Sometimes, however, the inflammation doesn’t go away. When the inflammation doesn’t go away in 6 months, the person has chronic hepatitis.

What is hepatitis A?

Hepatitis A (Hep A) is liver inflammation caused by the hepatitis A virus. Hepatitis A is different from other types of hepatitis. It isn’t typically as serious as hepatitis B or C, and it doesn’t usually develop into chronic hepatitis or cirrhosis (late-stage scarring of the liver).

Hepatitis A is very contagious. This means that you can easily catch the virus from someone or give it to someone else. You are most contagious soon after you are infected and before symptoms appear. Adults who are otherwise healthy are no longer contagious 2 weeks after the illness begins. Children and people who have a weak immune system may be contagious for up to 6 months.

Symptoms of hepatitis A

The hepatitis A virus is usually in your system for 2 to 6 weeks before symptoms appear. Some people never have symptoms. If symptoms do appear, they can appear suddenly and may include:

• Nausea
• Vomiting
• Jaundice (the yellowing of the skin and the whites of the eyes)
• Low-grade fever (fever up to 102°F)
• Fatigue
• Pain in your abdomen, especially on your right side
• Dark-colored urine
• Loss of appetite
• Muscle pain

Young children are likely to have mild cases of hepatitis A, while symptoms in older children and adults are more likely to be severe.

What causes hepatitis A?

Hepatitis A is caused by infection with the hepatitis A virus. You get the virus when you unknowingly eat a small amount of infected feces. This can happen through person-to-person contact, or through eating or drinking contaminated food or water.

A person can have and spread hepatitis A, even if that person does not have any symptoms. You are most likely to get hepatitis A from another person when:

• A person who has the virus does not wash their hands properly after going to the bathroom
• A parent does not wash their hands properly after changing the diaper of an infected child
• A caregiver does not wash their hands properly after cleaning up the stool of an infected person
• A person has sex with a person who has the virus

You can also get infected with hepatitis A by eating contaminated food or drinking contaminated water. Contaminated food and water are more common in developing countries. When traveling in areas where hepatitis A is common, avoid eating raw fruits and vegetables, shellfish, ice, and untreated water.

How is hepatitis A diagnosed?

See your doctor if you have any of the symptoms of hepatitis A. They can do a blood test to see if you have the disease.

Hepatitis A treatment

There is no specific medicine to treat or cure hepatitis A. If you have the virus, your body will eventually get rid of the infection on its own. You probably will feel sick for a few months before you begin to feel better.

To help your liver heal, you should get plenty of rest, eat a balanced diet and avoid alcohol and acetaminophen (one brand name: Tylenol). Talk with your doctor before you take any prescription medicines, over-the-counter medicines, vitamins, or supplements. Alcohol, acetaminophen, and certain other medicines, vitamins, and supplements can cause more damage to your liver.

You may need to stay in the hospital for a short time if you get dehydrated, have severe pain, suddenly become confused, or develop bleeding problems.

Can hepatitis A be prevented or avoided?

The best way to protect yourself against hepatitis A is to get the vaccine. The hepatitis A vaccination is recommended for all children older than age 1. It begins to protect you only 4 weeks after you are vaccinated. A 6- to 12-month booster is required for long-term protection. Ask your doctor if the vaccination is right for you.

You should also wash your hands with soap and warm water before and after cooking, after using the bathroom, and after changing diapers.

Wash fruits and vegetables thoroughly before eating and avoid raw or undercooked meat and fish.

You are at higher risk for hepatitis A if you:

• Live with or have sex with someone who has hepatitis A
• Travel to countries where hepatitis A is common
• Are a man who has sex with other men
• Use illegal drugs
• Have a clotting-factor disorder (such as hemophilia)

Living with hepatitis A

Once you recover from hepatitis A, you develop antibodies that protect you from the virus for life, according to the Centers for Disease Control and Prevention.

Questions to Ask Your Doctor

• Do I need treatment?
• What treatment is best for me?
• Will I need be hospitalized?
• Are there any medicines I should avoid taking?
• Are there foods I should avoid eating?
• Can I drink alcohol?
• How can I protect my family from getting hepatitis A?
• If I’ve had hepatitis A, am I at higher risk of getting other types of hepatitis?
• Will I have permanent liver damage?
• How soon before I travel should I be vaccinated?

Resources

American Liver Foundation: Hepatitis A

Hepatitis A

Hepatitis A

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• Hepatitis A

Key Facts

• Hepatitis A is an inflammatory disease of the liver that can be mild or severe.
• Hepatitis A virus (HAV) transmission occurs through ingestion of contaminated food and water or through direct contact with an infected person.
• Almost all patients with hepatitis A are completely cured and develop lifelong immunity. However, in very rare cases, infection with the hepatitis A virus can lead to fulminant hepatitis with a fatal outcome.
• The risk of contracting hepatitis A occurs when there is no safe water supply, poor sanitation and poor hygiene practices (such as infection and contamination of the hands).
• A safe and effective vaccine is available to prevent hepatitis A.

Overview

Hepatitis A is an inflammatory disease of the liver caused by the hepatitis A virus (HAV). The virus is spread primarily by an uninfected (and unvaccinated) person ingesting food or water contaminated with the faeces of an infected person. This disease is closely associated with poor water supply or contaminated food, poor sanitation, poor personal hygiene, and oral-anal sex.

Unlike hepatitis B and C, hepatitis A does not cause chronic liver disease, but can be accompanied by severe symptoms and sometimes progresses in a fulminant form (with acute liver failure), often resulting in death. In 2016, WHO estimated that hepatitis A killed 7134 people worldwide (representing 0.5% of all deaths from viral hepatitis).

Hepatitis A is present throughout the world and occurs both in the form of isolated cases and in the form of epidemics that tend to be cyclical. Epidemics caused by contamination of food or drinking water can be explosive, such as the epidemic in Shanghai in 1988, which affected approximately 300,000 people (1) . Epidemics can also be protracted and affect entire communities for several months as a result of person-to-person transmission. The hepatitis A virus persists in the environment for a long time and can remain viable even after food processing processes commonly used to control or inactivate bacterial pathogens.

Geographic distribution

Hepatitis A virus prevalence areas can be subdivided into areas with high, medium or low infection rates. At the same time, the rate of infection is not always identical to the incidence, since in young children the infection occurs with mild symptoms.

In low- and middle-income countries with poor sanitation and hygiene standards, infection is widespread and most children (90%) is infected with hepatitis A virus before the age of 10 years, most often with asymptomatic infection (2) . High-income countries with good sanitation have low infection rates. The disease can occur among adolescents and adults from high-risk groups, such as people who inject drugs, men who have sex with men, and people visiting areas with high hepatitis A endemicity, as well as isolated populations, such as closed religious groups. In the United States of America, major outbreaks of hepatitis A are occurring among homeless people. In middle-income countries and areas with heterogeneous sanitation conditions, a large proportion of the population is immune to infection in early childhood and reaches adulthood without developed immunity.

Transmission of infection

The main mechanism of transmission of hepatitis A virus is fecal-oral transmission, in which infection with the virus occurs as a result of the consumption of food or water contaminated by the feces of an infected person by an uninfected person. At the household level, infection can occur when an infected person fails to practice good hand hygiene when preparing food for other family members. Outbreaks of waterborne diseases, although rare, are usually associated with the consumption of contaminated sewage or inadequately treated water.

The virus can also be transmitted through close physical contact (eg, oral-anal sex) with an infected person, but normal household contact does not transmit the virus.

Symptoms

The incubation period for hepatitis A is usually 14-28 days.

Symptoms of hepatitis A can range from mild to severe and may include fever, malaise, loss of appetite, diarrhea, nausea, abdominal discomfort, dark urine, and jaundice (yellowing of the eyes and skin). The full spectrum of symptoms does not occur in all infected people.

Clinical symptoms of the disease occur more often in adults than in children. The prevalence of severe forms of the disease and mortality are higher among the older age groups. In children under 6 years of age, the infection is usually mildly symptomatic, and jaundice develops in only 10% of cases. In some patients, hepatitis A recurs, and a newly recovered person becomes ill again in an acute form. After that, the disease usually ends in complete recovery.

Who is at risk?

Anyone who has not been vaccinated or has not had the disease in the past can become infected with the hepatitis A virus. In areas with high virus circulation (high endemicity), most hepatitis A infections occur in early childhood. Risk factors include:

• unsatisfactory sanitary conditions;
• no safe water supply;
• the presence of an infected person among family members;
• sexual contact with a person with acute hepatitis A;
• recreational use of psychoactive substances;
• same-sex sex with men; and
• travel to areas of high endemicity without prior immunization.

Diagnosis

Hepatitis A does not differ clinically from other types of acute viral hepatitis. An accurate diagnosis is confirmed by a blood test for the presence of HAV-specific immunoglobulin M (IgM). In addition, reverse transcription polymerase chain reaction (RT-PCR) testing can be performed to detect hepatitis A virus RNA, which may require a referral to a specialized laboratory.

Treatment

There is no specific treatment for hepatitis A. The healing process can be slow and take weeks or months. It is important to refrain from unjustified prescribing of drugs. Acetaminophen, paracetamol and antiemetics should not be prescribed.

In the absence of acute liver failure, hospitalization of patients is not required. Treatment is aimed at maintaining comfort and a balanced diet, including replenishing fluid losses caused by vomiting and diarrhea.

Prevention

The most effective means of controlling hepatitis A are improved sanitation, food safety, and increased vaccination coverage.

The prevalence of hepatitis A can be reduced by:

• ensuring an adequate supply of safe drinking water;
• organization in settlements of proper wastewater disposal; and
• maintaining good personal hygiene, such as washing hands regularly before meals and after going to the toilet.

Several injectable, inactivated hepatitis A vaccines are available on the world market. All provide comparable levels of protection against the virus and have similar side effects. None of the vaccines are licensed for children under one year of age. China also uses an attenuated live vaccine.


WHO activities

In May 2016, the World Health Assembly adopted the first Global Health Sector Strategy on Viral Hepatitis 2016–2021. It highlights the critical role of universal health coverage and sets targets aligned with the Sustainable Development Goals. The strategy was to achieve the goal of eliminating viral hepatitis as a public health problem by 2030 (defined as a reduction of 90% new cases of chronic infections and a 65% reduction in mortality compared to the 2015 baseline) and included an action plan to achieve elimination through the implementation of key prevention, diagnosis, treatment and community outreach strategies. In May 2022, the Seventy-fifth World Health Assembly took note of a set of new comprehensive global health sector strategies for HIV, viral hepatitis and sexually transmitted infections for the period 2022–2030. Based on these previous and newly adopted strategies, many Member States have developed comprehensive national hepatitis programs and strategies to achieve elimination, guided by the global health sector strategy.

To support countries in achieving the global hepatitis targets of the 2030 Agenda for Sustainable Development, WHO works in the following areas:

• raising awareness, promoting partnerships and mobilizing resources;
• developing evidence-based policies and collecting evidence for action;
• ensuring health equity in the fight against hepatitis;
• prevention of the spread of infection; and
• expanded coverage of screening, care and treatment services.

WHO organizes an annual World Hepatitis Day event (one of its nine major annual public health campaigns) to raise awareness and understanding of the problem of viral hepatitis. In 2022, WHO is celebrating World Hepatitis Day with the slogan “ Providing Hepatitis Care Nearby” ” and calls for streamlining the delivery of viral hepatitis services, making them more accessible to the public.

Hepatitis A: symptoms, diagnosis, treatment

Hepatitis A is an infectious liver disease caused by a virus.

The hepatitis A virus has an acid-resistant envelope. This helps viruses that have entered contaminated food and water to pass the acidic protective barrier of the stomach. The hepatitis A virus is stable in the aquatic environment, so epidemics of hepatitis A are often transmitted by water. The hepatitis A virus is highly immunogenic, after the illness, a stable lifelong immunity is formed.
Hepatitis A is one of the most common human infections. In countries with warm climates and poor sanitation, hepatitis A is very common. It is known that in Central Asia almost all children are ill with hepatitis A. In Eastern Europe, the incidence of hepatitis A is 250 per 100,000 population per year.
The source of infection for is a person with hepatitis A who sheds billions of viruses into the environment through faeces. When drinking water or food contaminated with the hepatitis A virus (especially poorly thermally processed seafood), the viruses enter the intestines, then, being absorbed, they enter the liver with the blood stream and invade its cells – hepatocytes. Virus particles-virions multiply in the cytoplasm of liver cells. After leaving the liver cells, they enter the bile ducts and are excreted with bile into the intestines. The inflammatory process in the liver, leading to damage to hepatocytes, has an immunological basis. Cells of the human immune system, T-lymphocytes, recognize virus-infected hepatocytes and attack them. This leads to the death of infected hepatocytes, the development of inflammation (hepatitis) and impaired liver function.
Hepatitis A virus is transmitted by faecal-oral-water and ingestion. Hepatitis A is most likely to be contracted in hot countries, including those where traditional places of tourism and recreation are located. First of all, these are the countries of Africa (including Egypt and Tunisia), Asia (Turkey, Central Asia, India and Southeast Asia, including the islands), some countries of South America and the Caribbean. Hepatitis A is primarily a childhood infection. Many children carry the infection in an anicteric form and hepatitis A is not recognized during this period.
In developed countries, hepatitis A, also called “dirty hands disease “, is difficult to get sick due to the high culture of the population and the excellent work of communal services. Therefore, there are very few people who have antibodies to this infection, and the risk of getting sick upon contact with the hepatitis A virus is quite high. More often this happens during business trips and tourist trips to hot countries, to African and Asian resorts, to the republics of Central Asia.

When buying fruits and vegetables in the market, do not forget to wash them properly , always cook seafood.
Healthy people can be in contact with the sick, observing the elementary rules of hygiene. However, it is better to isolate children from patients.

To determine the likelihood and risk of infection with , but rather to decide whether vaccination is necessary, a blood test for the presence of antibodies to the hepatitis A virus of the immunoglobulin G class ( anti – HAV IgG ) is performed. If these antibodies are found in the blood, then contact with the virus was: infection or vaccination. This means that you have immunity to the virus, which means that the risk of infection is zero and vaccination against hepatitis A is not needed. It is almost impossible to get hepatitis A again. If there are no antibodies, then there is a risk. You need a vaccination. There is a special drug – immunoglobulin, which can be administered immediately before a possible infection or within 2 weeks after infection. This will allow for a short time to protect either from infection or from the development of the disease in case of infection.

Risk of contracting hepatitis A , and when vaccination is necessary (vaccination against hepatitis A):

• Family members (household members) of a person infected with hepatitis A virus
• Persons who have sex with an infected person
• People (especially children) living in areas with a high prevalence of hepatitis A
• Travelers traveling to countries with a high incidence of hepatitis A

What to do if there is a patient with hepatitis A in the family?

It is recommended that all family members be screened for antibodies to hepatitis A (anti-HAV IgG). In the absence of these antibodies, vaccination is necessary. Remember to follow the simplest rules of hygiene: wash your hands with soap and water after using the toilet and using the bathroom, after caring for a small child, before eating and preparing food.

Hepatitis A clinic

Within a month (incubation period 15-50 days, average 30) after the alleged infection, you can expect the main symptoms: fever, dyspepsia (nausea, vomiting, heaviness in the stomach and right hypochondrium), weakness, darkening urine (the color of strong brewed tea, frothiness) and then jaundice – yellowing of the sclera, skin, discoloration of feces. After the onset of jaundice, the general condition often improves slightly. Jaundice lasts about 3-6 weeks, sometimes longer. The disease lasts on average about 40 days. This largely depends on age, the state of immunity, the presence of concomitant chronic diseases, and the strict implementation of the doctor’s recommendations. Some people (about 15%) have a long-term course of hepatitis A, within 6-9months. Recovery usually follows. Most cases of hepatitis A have typical symptoms, leading to recovery.

The infection is most severe in children under one year of age , adults and the elderly. In adults, the infection often proceeds with severe intoxication and jaundice, on average they get sick for about 3 months. The risk of death in hepatitis A is 0.1% in children, 0.3% in adolescents and adults. All acute hepatitis of any origin are manifested by the same signs, so you need to see a doctor and conduct a full examination.

Diagnosis of hepatitis A

In addition to collecting an epidemiological history (where the person was during the last month, what he ate, what kind of water he drank, whether he had contact with patients with jaundice, etc.) and examination, test results are required (general blood count, biochemical blood tests, analysis for markers of viral hepatitis, coagulogram, urinalysis).

The criterion for the diagnosis of acute hepatitis A is the presence in human blood of antibodies to hepatitis A, related to class M immunoglobulins (anti – HAV IgM). These antibodies are found only in the acute period, with recovery, their titer decreases.

Hepatitis A treatment

Modern treatment is more focused not on fighting hepatitis A viruses, but on reducing the concentration and removal from the body of harmful substances that appear when the liver is damaged and functions are impaired. Therefore, detoxification solutions, glucose, vitamins, hepatoprotectors (drugs that protect liver cells) are administered. The decision to prescribe special antiviral therapy is made by the doctor. Hepatitis A ends with recovery.
The prognosis is favorable, liver function is usually fully restored. In the acute period, it is necessary to adhere to a sparing diet, physical and mental rest is observed.

Hepatitis A prevention, vaccination

Quite effective vaccines have been developed to protect against hepatitis A. These vaccines are killed hepatitis A viruses and are highly immunogenic. The vaccine is administered twice with an interval of 6-12 months. After the first dose of the vaccine, antibodies to the hepatitis A virus appear in most vaccinated people after 2 weeks.