Hepatitis: frequently asked questions
What is World Hepatitis Day?
At its 2010 meeting, the World Health Assembly resolved that July 28 should be designated as World Hepatitis Day. World Hepatitis Day is an opportunity for education and greater understanding of viral hepatitis as a global public health problem, and to stimulate the strengthening of preventive and control measures of this disease by nations around the world.
Why is it needed?
Hepatitis is one of the most prevalent and serious infectious conditions in the world, but many people - including health policy makers - remain unaware of its staggering toll on global health.
What is hepatitis?
Hepatitis is an inflammation of the liver, most commonly caused by a viral infection. There are five main hepatitis viruses, referred to as types A, B, C, D and E. These five types are of greatest concern because of the burden of illness and death they cause and the potential for outbreaks and epidemic spread. In particular, types B and C lead to chronic disease in hundreds of millions of people and, together, are the most common cause of liver cirrhosis and cancer.
Hepatitis A and E are typically caused by ingestion of contaminated food or water. Hepatitis B, C and D usually occur as a result of parenteral contact with infected body fluids. Common modes of transmission for these viruses include receipt of contaminated blood or blood products, invasive medical procedures using contaminated equipment and for hepatitis B transmission from mother to baby at birth, from family member to child, and also by sexual contact.
Acute infection may occur with limited or no symptoms, or may include symptoms such as jaundice (yellowing of the skin and eyes), dark urine, extreme fatigue, nausea, vomiting and abdominal pain.
What makes hepatitis a global health problem?
About 1 million deaths per year are attributed to viral hepatitis infections. Together, hepatitis B virus (HBV) and hepatitis C (HCV) are the leading cause of liver cancer in the world, accounting for 78 percent of cases.
Nearly one out of every three people in the world (approximately 2 billion people) has been infected by HBV, and one in twelve live with chronic HBV or HCV infection. While most people who have been infected with these viruses are unaware of their infection, they face the possibility of developing debilitating or fatal liver disease at some point in their lives and unknowingly transmitting the infection to others.
HBV/HIV and HCV/HIV coinfections are an increasing problem in countries with HIV epidemics and among injecting drug users. For co-infected persons being treated with HIV antiretroviral medicines, underlying viral hepatitis is becoming a major cause of death.
What are the different hepatitis viruses?
Scientists have identified five unique hepatitis viruses, identified by the letters A, B, C, D, and E. While all cause liver disease, they vary in important ways.
Hepatitis A virus (HAV) is present in the faeces of infected persons and is most often transmitted through consumption of contaminated water or food. Certain sex practices can also spread HAV. Infections are in many cases mild, with most people making a full recovery and remaining immune from further HAV infections. However, HAV infections can also be severe and life threatening. Most people in areas of the world with poor sanitation have been infected with this virus. Safe and effective vaccines are available to prevent HAV.
Hepatitis B virus (HBV) is transmitted through exposure to infective blood, semen, and other body fluids. HBV can be transmitted from infected mothers to infants at the time of birth or from family member to infant in early childhood1. Transmission may also occur through transfusions of HBV-contaminated blood and blood products, contaminated injections during medical procedures, and through injection drug use. HBV also poses a risk to healthcare workers who sustain accidental needle stick injuries while caring for infected-HBV patients. A safe and effective vaccine is available to prevent HBV.
Hepatitis C virus (HCV) is mostly also transmitted through exposure to infective blood. This may happen through transfusions of HCV-contaminated blood and blood products, contaminated injections during medical procedures, and through injection drug use. Sexual transmission is also possible, but is much less common. There is no vaccine for HCV.
Hepatitis D virus (HDV) infections occur only in those who are infected with HBV. The dual infection of HDV and HBV can result in a more serious disease and worse outcome. Safe and effective hepatitis B vaccines provide protection from HDV infection.
Hepatitis E virus (HEV), like HAV, is transmitted through consumption of contaminated water or food. HEV is a common cause of hepatitis outbreaks in developing parts of the world and is increasingly recognized as an important cause of disease in developed countries. Safe and effective vaccines to prevent HEV infection have been developed but are not widely available.
Why is it important for people to know if they are infected with a form of viral hepatitis?
Early diagnosis provides the best opportunity for effective medical support. It also allows those infected to take steps to prevent transmission of the disease to others, for example by adopting safe sex practices. It allows lifestyle precautions to be undertaken to protect the liver from additional harm, specifically, by eliminating alcohol and certain drugs which are toxic to the liver.
How can viral hepatitis be prevented?
- Safe and effective vaccines are widely available for the prevention of HAV and HBV infection.
- Screening blood used for transfusion can prevent transmission of HBV and HCV.
- Sterile injection equipment protects against HBV and HCV transmission.
- Safer sex practices, including minimizing the number of partners and using barrier (condom) protective measures has been shown to protect against HBV and HCV transmission.
- Harm reduction for injection drug users prevents HBV and HCV transmission.
- Safe food and water provide the best protections against HAV and HEV.
How is viral hepatitis treated?
Antiviral agents active against HBV exist. Treatment of HBV infection has been shown to reduce the risk of liver cancer and death. It is estimated that 20–30% of persons with HBV infection could benefit from treatment. However, drugs active against HBV are not widely available or utilized in persons infected with HBV. Currently recommended antiviral agents used for treatment of human immunodeficiency virus (HIV) infection do not adequately suppress HBV, which is of great concern for the estimated 10% of the HIV-infected persons in Africa who are co-infected with HBV.
HCV is generally considered to be a curable disease but for many persons this is not a reality. Scientific advances and intense research and development have led to the development of many new oral antiviral drugs for HCV infection. A great number of HCV specific oral drugs are in the late stage of development; some have been recently registered. These are more effective and better tolerated. Much still needs to be done to ensure that these new treatment advances lead to greater access and treatment responses in resource constrained areas of the world.
What is WHO doing to support the fight against viral hepatitis?
WHO has worked closely with Member States to achieve some very notable achievements in hepatitis prevention. In 2009, over 91% of Member States now include the hepatitis B vaccine in their infant immunization programs and over 70% of infants received 3 doses of this vaccine which provides them with life-long protection from this one virus.
WHO is assisting countries in ensuring the safety, availability, and quality of blood and blood products.
Policy guidance and guidelines on best practices are available for all injections including phlebotomy and lancet procedures. They enable countries to establish safe injection and phlebotomy services, train health care workers on best injection and phlebotomy practices and ensure that patients and health workers are safe when receiving or giving an injection or a phlebotomy.
More needs to be done to prevent and control viral hepatitis. We must ensure that those already infected with viral hepatitis have timely access to testing, care and effective treatments to delay development of disease and prevent disability.
WHO is working in the following areas:
- raising awareness, promoting partnerships and mobilizing resources
- evidence-based policy and data for action
- prevention of transmission
- screening, care and treatment.
To accomplish this mandate, WHO will take a health systems approach, including developing new approaches at WHO and mobilizing much needed resources.
WHO will work in close collaboration with all our partners to prevent and control viral hepatitis.
1 HBV can be transmitted from a family member to infant in early childhood. Most commonly this occurs through an “unapparent infection” where an HBV positive family member or other adult is in frequent contact with an uninfected child. They may cause infection through means that are not obvious (e.g. small cut on hand of the adult to a child with dry skin (eczema) with cracking). What makes these exposures a source of infection is probably not any one exposure but the cumulative nature of being exposed frequently over the course of time.