Hepatitis is an acute or chronic inflammation of the hepatocytes (liver cells which make up to about 70 - 80% of the total mass of the liver), resulting in damage to the liver. Most people associate hepatitis with viral hepatitis, but the term actually encompasses a much broader range of pathophysiological conditions leading to it. Among the non-infectious causes, it can be the result of chronic alcoholism, an autoimmune disorder or can be drug-induced. Some species of bacteria also cause hepatitis. However, viral hepatitis is undoubtedly more prevalent, and is more focused upon. Also, it has the potential of causing other deadly diseases such as liver cancer, which makes it all the more important to be aware of all aspects of this disease.
The causative agents of viral hepatitis are the hepatotropic viruses as well as some others like the Epstein-Barr virus (EBV) and the Cytomegalovirus (CMV). Among these, the incidence of hepatitis caused by the hepatotropic viruses is greater. The transmission of the viruses, their symptoms, progression of the disease, and treatment, all vary depending on which type a person gets infected with. The three types of major hepatotropic viruses that cause hepatitis are hepatitis A virus, hepatitis B virus and hepatitis C virus.
Hepatitis A has been known for a long time as "infectious hepatitis" and is caused by the hepatitis A virus (HAV). It causes acute infection but does not cause chronic hepatitis
, and development of fulminant hepatitis, which is a severe form of viral hepatitis
of a life-threatening nature, is rare. It also is not associated with the development of hepatocellular carcinoma or liver cancer, compared to the hepatitis B and C viruses that have a strong correlation with this type of cancer
. It does not cause a carrier state.
Method of transmission
The virus is found in the faeces of an infected person, 2-4 weeks before and about 5 to 6 days after the start of acute symptoms. The virus spreads through food and/or water, contaminated with the faeces of persons infected with the virus. It also spreads by sexual practices (e.g., rimming) which entails anal-oral contact between an infected and uninfected person. The hepatitis virus A
is, however, not spread by body fluids such as urine, saliva or semen. Another route through which the virus enters the body is through the consumption of seafood obtained from water contaminated with human sewage.
Hepatitis A may be asymptomatic meaning that after contracting the virus, a person may have no symptoms at all and the only way he/she might come to know about it is through antibodies for anti-HAV, showing up in a blood test
. Those who suffer from an acute symptomatic infection usually have the following symptoms:
- Malaise, which is a feeling of debility the person feels drained of energy
- Inability to eat proper meals due to loss of appetite
- Bouts of nausea
- Aches and pains (a person may have dull headaches and pain in joints and muscles)
- Slight fever
- Appearance of dark-coloured urine
- Skin and eyes both look yellowish
- The colour of faeces may become lighter
- Enlarged liver
There are no antiviral drugs for hepatitis A or any other kind of treatment aimed at eradicating the virus from the body. A person suffering from the acute infection needs to take rest to recuperate. Although there is no treatment, preventive measures in the form of hepatitis A vaccine can be taken, especially if a person is planning to undertake international travel. The Centers for Disease Control and Prevention (CDC) recommend all children between 12 to 23 months to be vaccinated. Vaccination is also recommended by them for the following high-risk groups: health care workers, homosexuals, street drugs users, those adopting a child, those working in a lab with HAV or who work with HAV-infected primates and those suffering from chronic liver disease
It is widely known as "serum hepatitis" and is caused by the hepatitis B virus. It can cause acute as well as chronic hepatitis, fulminant hepatitis or a progressive chronic form of hepatitis leading ultimately to cirrhosis. It is associated with the development of hepatocellular carcinoma in those with the chronic infection. It can lead to a carrier state in a small percentage of blood donors and in newborn babies
whose mothers have contracted the virus at some point in their life.
Method of transmission
Unlike the hepatitis A virus, the virus for hepatitis B does not spread by faeces. It is present in blood at all stages of the infection, so it spreads easily through blood transfusion
, intravenous drug use and accidental pricking with contaminated needles. It also appears in all body fluids like semen, saliva, breast milk and sweat. It spreads by sexual practices
in both heterosexual and homosexual individuals. It can live outside the body for around a week, so it can enter the body via broken skin coming in contact with contaminated objects. The virus has an incubation period of 4-25 weeks.
Hepatitis B virus may cause an asymptomatic infection. The symptoms of acute infection are mostly the same as that for hepatitis A infection. Symptoms of Acute Infection include:
- A persistent feeling of tiredness
- Nausea and vomiting
- Loss of appetite
- Pain in the abdomen and in the joints and muscles
- Some patients develop rash, fever and other severe symptoms
A number of serological tests diagnose the presence of hepatitis B virus. The presence of the HBsAg, anti-HBc and IgM anti-HBc is interpreted as a sign of acute infection, while in chronic infection, presence of HbsAg
(for more than 6 months) and anti-HBc are taken to be positive. Also, presence of HBeAg
and serum HBV DNA are also considered signs of chronic infection.
There are many treatment options available for treating hepatitis B infection
. Some of them are:
It is an approved treatment for chronic infection with HBV. It is administered by subcutaneous or intramuscular injection three times a week for about 16 weeks. Adverse effects associated with interferon-alfa are fever, malaise, chills, muscle pain
and many other flu-like symptoms.
It is an orally administered drug with a dose of 100-300 mg, to be taken daily for more than a year. A combination treatment with interferon-alfa also gives good results in many patients. Resistance to lamivudine may develop in some persons after stopping the therapy.
It is administered orally at a dose of 100 mg daily for about a month. It is active against strains of hepatitis B that have become resistant to lamivudine
. Other anti-viral drugs for hepatitis B are Famciclovir
and Fialuridine. The best course of action is to get vaccinated so that even if you do contract the infection, your immune system is ready for the virus. The vaccine can be administered as a shot by itself or in the same shot with other vaccines. High-risk groups who need to get vaccinated include those at risk for hepatitis A. It also includes those who are on kidney dialysis and those who suffer from diabetes
less than 60 years of age.
Caused by the hepatitis C virus
(HCV), hepatitis C has a high incidence of progressing to the chronic form of the disease. It can also lead to the development of hepatocellular carcinoma. Development of fulminant hepatitis with HCV is extremely rare. The infection can lead to an asymptomatic chronic carrier state in most people who become infected which in turn can lead to cirrhosis of the liver
Method of Transmission
The hepatitis C virus does not appear to spread by sharing food or drink of an infected person. It also does not appear in breast milk. The greatest spread of HCV is through contact with the blood of an infected individual. Any activity that involves using sharp objects with the blood of a person having the HCV is highly likely to spread the infection. High-risk sexual activity
(involving cuts, bruises) can lead to HCV transmission.
The infection with HCV can be acute or chronic. Mostly, people remain asymptomatic after contracting the infection. The symptoms that do appear are similar to those of other hepatitis virus types like general malaise, nausea, vomiting, low-grade fever
, fatigue, pain in muscles, dark urine and jaundice (yellowing of eyes and skin). The chronic state is also frequently asymptomatic, and the symptoms that do appear, do so only after the beginning of cirrhosis. The one feature that distinguishes HCV infection from others is that there is a cycle of periods of dormancy followed by liver damage
due to re-activation of the virus.
The diagnosis is done by serological tests that test for anti-HCV antibodies. This test is called the second generation enzyme immunoassay (EIA-2). A PCR test for HCV RNA also is used to confirm the diagnosis.
Treatment options are chosen by a doctor based on the risk posed by liver damage to the patient. Peginterferon-alfa-2a, peginterferon-alfa-2b or Ribavirin
are used. According to CDC, a vaccine for hepatitis is not available, but efforts are underway to develop it.
Therefore, it is important to remember that vaccination
, hygiene, staying away from high-risk sexual activities and avoiding drug abuse are the only sure ways to avoid contracting hepatitis viruses. As the old adage goes, prevention is better than cure.