Unit 12A: section A, case study
Infectious diseases – Hepatitis B
Introduction
The infectious disease, hepatitis B, is caused by the hepatitis B virus pathogen. It is serious infection,
centred in the liver. Depending on the person infected, the disease can last for less than a half a
year, or it can become chronic, if it lasts for longer. If the condition transitions into the chronic state,
it can cause serious complications and may increase the risk of liver cancer, liver failure or cirrhosis
(permanent scarring of the liver). The chronic stage of the disease is most likely to affect people of a
young stage in their life (infants and children) (Mayo clinic 2020).
The symptoms of the disease
The warning signs and symptoms of the disease can vary from mild to severe. They usually appear
around one to four months after being infected, they can sometimes appear as early as two weeks
after infection.
The usual symptoms of hepatitis B virus include:
o Abdominal pain
o Fatigue/weakness
o Loss of appetite
o Pain of the joints
o Dark urine (concentrated)
o Nausea and vomiting
o Jaundice (yellowing of skin and eyes)
A doctor should be contacted immediately if a person thinks they have been infected by the
hepatitis B virus, if they show most of the symptoms; a preventative treatment can also be
recommended if a person has been exposed to the virus in the last twenty- four hours (Mayo clinic
2020).
The lifecycle of the hepatitis B virus
The life cycle of the hepatitis B virus is an extremely complicated process, even though we do not
fully understand the process, we can understand the stages and different concepts we already
understand to help make prophylaxis to destroy the virus. Firstly, the hepatitis B virus will enter the
human body, and will enter the liver cell, transporting into the nucleus of the host cell. The virus
does this to create replications of itself, by transforming into a ‘covalently closed circular DNA, also
written as cccDNA. The virus is then packaged and will leave the its host liver cell. Meanwhile, the
viral cccDNA will remain in the nucleus of the infected liver cell, where it will create new hepatitis
virus and will blend into the DNA of the liver cell. These stages will continue, completely infecting the
person (Hepatitis B Foundation 2020).
The virus’ specific biological mechanisms
Infectious diseases – Hepatitis B
Introduction
The infectious disease, hepatitis B, is caused by the hepatitis B virus pathogen. It is serious infection,
centred in the liver. Depending on the person infected, the disease can last for less than a half a
year, or it can become chronic, if it lasts for longer. If the condition transitions into the chronic state,
it can cause serious complications and may increase the risk of liver cancer, liver failure or cirrhosis
(permanent scarring of the liver). The chronic stage of the disease is most likely to affect people of a
young stage in their life (infants and children) (Mayo clinic 2020).
The symptoms of the disease
The warning signs and symptoms of the disease can vary from mild to severe. They usually appear
around one to four months after being infected, they can sometimes appear as early as two weeks
after infection.
The usual symptoms of hepatitis B virus include:
o Abdominal pain
o Fatigue/weakness
o Loss of appetite
o Pain of the joints
o Dark urine (concentrated)
o Nausea and vomiting
o Jaundice (yellowing of skin and eyes)
A doctor should be contacted immediately if a person thinks they have been infected by the
hepatitis B virus, if they show most of the symptoms; a preventative treatment can also be
recommended if a person has been exposed to the virus in the last twenty- four hours (Mayo clinic
2020).
The lifecycle of the hepatitis B virus
The life cycle of the hepatitis B virus is an extremely complicated process, even though we do not
fully understand the process, we can understand the stages and different concepts we already
understand to help make prophylaxis to destroy the virus. Firstly, the hepatitis B virus will enter the
human body, and will enter the liver cell, transporting into the nucleus of the host cell. The virus
does this to create replications of itself, by transforming into a ‘covalently closed circular DNA, also
written as cccDNA. The virus is then packaged and will leave the its host liver cell. Meanwhile, the
viral cccDNA will remain in the nucleus of the infected liver cell, where it will create new hepatitis
virus and will blend into the DNA of the liver cell. These stages will continue, completely infecting the
person (Hepatitis B Foundation 2020).
The virus’ specific biological mechanisms
