The Role of Immune System in Hepatitis Management
Hepatitis is an infectious disease of the liver and is caused by five kinds of viruses. Therefore, hepatitis is also known to be of five types, namely hepatitis A, hepatitis B, hepatitis C, hepatitis D, and hepatitis E. the body's response towards all these forms of hepatitis because they affect the body differently. The body's response towards any infectious disease is regulated by the immune system which responds via a systematic process. The immune mechanism of the body may not protect it from all diseases, especially those which spread via the blood. This article explains how the human immune system works and how it responds towards viral infections caused by different classes of Hepatitis Viruses.
Introduction: The Human Immune System
The human immune system is our protection mechanism against various infectious organisms and particles such as bacteria and viruses. The immune system is of two kinds, one which is innate i.e. present at time of birth, and adaptive i.e. one that is developed later in life as we are exposed to various environmental pathogens. Our immune system is spread as a network of cells throughout the body so that it can detect the entry of any foreign particle through any opening in the body. It is the function of the immune system to identify and attack, kill and eliminate all foreign matter from the body. Lymph plays an important role in the immune system. There are two kinds of lymph cells, known as B cells and T cells, that secrete special cells called antibodies that can stick on the foreign matter and then necessary action is taken.
Immune Response Towards Viral Infections
Both innate as well as adaptive mechanisms of immunity keep developing throughout life in order to control and manage infections. In case of viral infections, the immune system works by first recognizing nucleic acids present in the viruses, or the viral proteins, or the damage of the body tissues caused by these viruses. Actually, the innate immune mechanism plays a great role in the activation of the adaptive immune mechanism. The adaptive immune system then manufactures and supplies B cells and T cells throughout the body that are specifically efficient in recognition and killing of infected liver cells. This process develops an immune memory that helps protect an individual if he comes in contact with the same microbe for another time. Different kinds of microbes affect different organs in our body and produce different diseases and symptoms. With the development of our immune systems the microbes have also developed strategies to cheat and escape our immune system.
Types Of Hepatitis Infections And How Our Immune System Responds Towards Them
1. Hepatitis A
Hepatitis A is an infectious disease that is transmitted by an infected person's stool. Germs from this stool can then spread hepatitis B to people who have handled the stool with their hands, or have come in contact with water contaminated by the stool, or have prepared food with unwashed hands or with infected water. If an infected person prepares food for others, chances are that people who eat that food are also going to be infected
Hepatitis A is caused by the hepatitis A virus that enters via mouth and then travels to the liver of the person. It replicates itself in the liver cells and besides living in the liver it is also present in the feces or stool or the infected person. By the time the immune mechanism is activated, the virus keeps shedding through the stool and keeps damaging the liver. At the time the immune response is fully activated, the shedding of the virus stops and liver functions are also slowly restored to normal. Hepatitis A vaccine is available and is effective. The immune system is very effective in managing hepatitis A infection and the same person who has once recovered, doesn't again get infected by hepatitis A virus.
2. Hepatitis B
Hepatitis B is an infectious viral disease which spreads via body fluids including blood and semen. Thankfully, it is preventable because vaccines are available and are suitable for administration to pregnant women, children as well as adults. It is usually not life threatening, and individuals with this infection can live for upto 75 years. People can also recover completely from hepatitis B infection in two to three months.
Hepatitis B is caused by the virus called hepatitis b virus or HBV. Upon entering the body via body fluids, the HBV virus replicates inside the liver cells but doesn't damage them directly. The immune system instantly starts working after the person is exposed to the virus. It immediately starts producing cytokines that work against the virus and limits their spread in the initial stage itself. Therefore the multiplication of HBV is slowed down and delayed effectively by our immune system. If hepatitis B infection does not start resolving within one month of the infection, it is because viral proteins have been produced in uncontrollably large quantities. The reason behind it is that our immune system is unable to completely remove hepatitis B viruses from the body. Even in those individuals who have been declared as recovered from hepatitis B, there are residues of HBV DNA strands that remain in their bodies for the rest of their lives. These DNA strands stimulate special immune B and T cells that are specific to hepatitis B viruses. It develops a protective immunity in these individuals.
3. Hepatitis C
This form of viral hepatitis is a chronic condition which can also be life threatening. It is so because if hepatitis C is not discovered and treated soon after the infection, it causes growth of cancer in the liver cells. It is transmitted from person to person via blood i.e. from shared needles, razor blades, etc. and therefore the risk of transmission of HIV AIDS and hepatitis C is combined and needless to say, it is a very dangerous combination. In fact, hepatitis C aggravation is a major cause of death of individuals having an HIV AIDS infection.
Hepatitis C is caused by a virus known by the same name which is hepatitis C virus or HCV. This virus infects humans and chimpanzees only. Upon entering the body via bloodstream, the HC virus replicates very fast in the liver cells. The liver becomes infected at once and it causes an increase in the enzyme known as alanine aminotransferase (ALT) which is present in very low amounts in the liver cells of an individual in normal circumstances. This raised level of ALT in the blood is the first symptom of liver infection and damage, and is seen only around eight weeks after the virus has entered the body. The body starts developing antibodies especially suited for hepatitis C virus within this time. The innate immune mechanism i.e. that present in us at birth is responsible for dealing with HCV cells. These immune cells multiply in number and gather around the liver to protect it. However, the overall efficiency of the immune cells is decreased if the infected calls cannot be killed fast. Therefore hepatitis C leads to liver cirrhosis and cancer of liver cells.
How To Strengthen The Immune System And Prevent Infections?
Now that we have learnt that not only our personal hygiene but our immune system also plays an important role in protecting us from various chronic and acute illnesses, here are some steps that you can take in order to strengthen your immune system:
- Consume a balanced diet that fulfills all your dietary requirements.
- Maintain a healthy body weight.
- Quit smoking and limit your alcohol consumption.
- Stay up to date with vaccines and get the ones that you require.
- Do not buy or eat food from unhygienic places.
- Do regular exercise.
- Do not stress and take adequate sleep.
- Practice yoga.
The immune system plays a great role in prevention of disease. But for some diseases like hepatitis, even the immune response may not work in the favor of the body. Various infectious diseases can be prevented by knowing their method of communication, but practicing care and caution can help prevent all the diseases. Talking specifically about the hepatitis diseases, proper vaccination and practice of proper hygiene and safe intercourse is extremely important for preventing these infections. Immune system gets tired dealing with hepatitis infections. Therefore, in addition to taking care to avoid the infection, steps should be taken to strengthen the immune system.
Dr. Meenakshi Chauhan
MD (ALT. MEDICINE) View Profile