Pathogen

The structure of the Hepatitis C Virus

The Hepatitis C Virus, or HCV, is one of five different Hepatitis variants, A-E, which causes inflammation of the liver. A single stranded RNA virus, much like HIV, targets the cells in the liver and causes many problems. HCV is simply a strand of RNA surrounded by a protein coat called a capsid. It is therefore categorized as a retrovirus (retro = backwards) as the virus is in the form of RNA and not DNA. This entire body, labelled the nucleocapsid, is further enclosed by an envelope, an outer membrane derived from the host cell's membrane. The size of HCV however is only 40-60 nanometers in diameter (1 nanometer = 1 billionth of a meter).

Once inside, the capsid that protects the RNA uncoils itself and allows the RNA to be replicated by the cells own transcription resources. Since HCV is a retrovirus, it must supply its own enzyme called reverse-transcriptase to copy the RNA into DNA so that it can integrate itself into the cells DNA and be replicated. Once progeny have been replicated, these viruses from the Flaviviride family uses the cell's outer membrane as its outer protective layer, budding out from the cell and taking a portion of the membrane with it, thus becoming enveloped. Yet the fact that HCV is an enveloped virus means that it may be susceptible to any envelope attacking medications discovered in the future.

Scientists currently believe that HCV is solely a blood born virus yet it can be transferred through a multitude of paths, even some of which are not even known yet (see Sporadic Transmission in Modes of Transmission section).

Disease

If an acute HCV infection becomes chronic, chronic meaning that anti-HCV antibodies are present in the blood for over six months, many detrimental effects can take place. One possible outcome may be liver cirrhosis, destruction and breakdown of liver tissue. This occurs in twenty percent of patients with HCV and results in the necessity of a liver transplant. If one does receive a liver transplant, as there are a high demand for them, it will only be a matter of time before HCV begins to break down the new liver. Hepatitis C can also produce Hepatocellular carcinoma, or liver cancer. If either cirrhosis or hepatocellular carcinoma are not taken care of, the patient will die.

Symptoms

HCV can incubate in the human body for decades without showing symptoms. 80% of people infected show no signs of infection. People who received HCV in the 1960's from needle injections are just starting to show symptoms. These symptoms must be detected early on if one is to prevent chronic HCV. Acute HCV is diagnosed only by Hepatitis-like symptoms and then reaffirmed by tests later.

A cross-section of a normal, healthy liver

A cross-section of a liver damaged by cirrhosis

The eye of a person with jaundice

Acute HCV

• Enlarged and tender liver
• Jaundice -bile pigment that the liver cannot process turns skin and eyes yellow.
• Fatigue
• Nausea
• Alcohol intolerance
• Vomiting
• Flu like Symptoms
• Increased levels (up to ten times the normal level) of the liver enzyme Alamine Aminotransferase (ALT) determined through an enzyme test
• Presence of Anti-HCV antibodies determined through test
• Presence of HCV through a RT-PCR / DNA amplification test (Reverse Transcriptase - Polymerase Chain Reaction)

Chronic HCV

Anti-HCV antibodies and high ALT levels for over six months