The Nobel Assembly at Karolinska Institute, Sweden, decided to award the Nobel Prize in Medicine jointly to Harvey Alter, Michael Houghton and Charles Rice. They were awarded the prize for their discovery of the hepatitis C virus. Prior to their efforts, many individuals with chronic hepatitis went undetected in spite of testing negative for hepatitis A and B viruses. Their discovery has led to the identification of the hepatitis C virus that causes cirrhosis of liver and liver cancer in people around the world.
What is the significance of this Nobel Prize-winning discovery?
This is a huge development in the ongoing battle against viral infections. Highly sensitive blood tests are available to detect this infection in blood worldwide. This has eliminated blood transfusion hepatitis in many parts of the world. This has also hastened the discovery of many drugs to treat hepatitis C virus infection. This has raised hopes of eliminating this infection from the world.
Why was it so difficult to identify this virus?
This virus posed a great threat to the researchers themselves. They had to be extremely careful not to get infected themselves. No animal models were available as this was thought to be restricted only to humans. Eventually, chimpanzees were discovered to be ideal animal models. Besides being highly infectious, the virus was detected in a very minuscule quantity in human blood. The traditional methods to detect the virus were ineffective.
What are the symptoms of hepatitis C infection?
Long term infection with the hepatitis C virus is known as chronic hepatitis C. Chronic hepatitis C infection is a silent infection for many years until the virus damages the liver enough to cause symptoms. Bleeding and bruising easily, lack of appetite, tiredness, yellow eyes due to jaundice, dark urine, itching, fluid in the abdomen, swelling at ankles, weight loss is common in chronic cases. Confusion and slurred speech is observed in advanced cases.
What are the symptoms in the early phase of acute infection?
It rarely causes symptoms of drowsiness and goes undetected in the early phase. Symptoms in the acute phase may include fever, body aches, nausea, vomiting and jaundice. It does not always become chronic. Rates of spontaneous viral clearance and recovery are seen in 15% to 25% cases in the acute phase. Acute hepatitis C also responds well to antiviral therapy.
What are the risk factors to get hepatitis C infection?
If you are a healthcare worker who gets pricked by an infected needle containing the virus, the chances of getting the infection are high. If you are using illicit drugs intravenously or if you inhale them, it can get you infected. If you have HIV infection or have been tattooed with unsterile equipment if you have received a blood transfusion before 1992 or are on hemodialysis treatment for a long period of time, those born between 1945 and 1965 as this was the time when the incidence of hepatitis C was maximum and those who have received multiple blood transfusions or blood products as in thalassaemia or sickle cell disease or haemophilia are at increased risk.
What are the complications of hepatitis C infection?
If the infection continues for many years, it can cause significant complications. Long term infection can cause scarring and shrink of the liver known as cirrhosis of the liver. A small number of people with hepatitis C can have liver cancer. Advanced cirrhosis can cause liver failure.
How to prevent hepatitis C infection?
All blood transfusions are carried out by testing the blood to be transfused for the hepatitis C virus. Be cautious about body piercing and tattooing. Do not practice sex with multiple partners or with a partner whose health status is uncertain. How is hepatitis C virus diagnosed? The diagnosis of hepatitis C virus infection is done by a simple blood test. Liver function tests, ultrasound examination, the elasticity of liver, MRI of the liver, liver biopsy and genotype studies are other relevant tests done to assess the extent of infection and to plan a treatment protocol.
Is there a treatment for hepatitis C infection?
Anti-viral drugs are available to clear the virus from our blood. The aim of treatment is to have no hepatitis C virus in your body at least 12 weeks after you complete treatment. The choice of medications and the duration of treatment depends on the hepatitis C genotype, presence of existing liver damage, other medical conditions and prior treatments. If you have developed serious complications from hepatitis C infection, a liver transplant may be an option. Most transplanted livers come from deceased donors while a few can come from living donors.
What about vaccinations against hepatitis C?
There is no vaccine against hepatitis C virus. Your doctor will, however, recommend you to get vaccinated against hepatitis A and B viruses. These are separate viruses and can complicate the course of chronic hepatitis C virus infection. The discovery of the hepatitis C virus and subsequent modalities to diagnose, prevent and treat the infection has opened the doors to discover many other viruses. With the discovery of the hepatitis C virus, thousands of deaths have been prevented so far. Salute to these Nobel laureates for their discovery!