explained-the-discovery-of-hepatitis-c-virus-that-helped-three-scientists-win-the-medicine-nobel

Context: Americans Harvey J Alter and Charles M Rice, and British scientist Michael Houghton were awarded the Nobel Prize for Medicine or Physiology for the discovery of the hepatitis C virus.

More about news:

  • The Nobel Committee noted that the trio’s work helped explain a major source of blood-borne Hepatitis C virus that couldn’t be explained by the hepatitis A and B viruses.
  • Tests have been developed to identify blood that has this virus, so that infected blood is not given to any patient.

Nobel Prize

  • The prestigious Nobel award comes with a gold medal and prize money of 10 million Swedish kronor (over USD 1,118,000), courtesy of a bequest left 124 years ago by the prize’s creator, Swedish inventor Alfred Nobel.
  • The Nobel Committee often recognizes basic science that has laid the foundations for practical applications in common use today.
  • The award is the first of six prizes being announced through October 12.
  • The other prizes are for outstanding work in the fields of physics, chemistry, literature, peace and economics.

Significance of discovery

  • According to the World Health Organization, about 71 million people (6 -11 million of them in India) have chronic infection with the Hepatitis C virus, which also happens to be a major cause of liver cancer. 
  • No vaccine: A vaccine for the disease has still not been developed.
  • The disease is hard to detect because it remains asymptomatic for a long time before leading to liver cirrhosis or liver cancer.
  • The discoveries of Hepatitis B and C (HBV and HCV), and the establishment of effective screening routines, have virtually eliminated the risk of transmission via blood products.
  • Three main causes of blood-borne infections — Hepatitis B, Hepatitis C and HIV — all have been identified.

India and Hepatitis C

  • With a target to eliminate Hepatitis C by 2030, India has managed to put 50,000 people on treatment since 2018, when the National Viral Hepatitis Control Programme (NVHCP), was launched.
  • An estimated 0.5-1 per cent of the country’s population (or 10-13 million people) suffers from Hepatitis C.
  • Punjab has a larger burden of disease due to high drug-abuse and injectable drugs usage. 

What is Viral Hepatitis?

  • Hepatitis means inflammation of the liver. 
  • The liver is a vital organ that processes nutrients, filters the blood, and fights infections. When the liver is inflamed or damaged, its function can be affected. 
  • Heavy alcohol use, toxins, some medications, and certain medical conditions can cause hepatitis. 
  • However, hepatitis is often caused by a virus. 
  • The most common types of viral hepatitis are hepatitis A, hepatitis B, and hepatitis C.
  • There are five main strains of the hepatitis virus – A, B, C, D and E.  Together, hepatitis B and C are the most common cause of deaths, with 1.3 million lives lost each year. 
  • The hepatitis A virus (HAV) is transmitted through ingestion of contaminated food and water or through direct contact with an infectious person. Almost everyone recovers fully from hepatitis A with a lifelong immunity.
  • Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus (HBV). 
  • Hepatitis C is a liver disease caused by the hepatitis C virus (HCV).
    • Houghton was able to identify the new virus in 1982, after which it was named Hepatitis C.
  • How do they spread?
    • Like HIV, the hepatitis B and hepatitis C viruses spread.
  • By sharing needles, syringes, and other injection equipment.
  • From mother to child: Pregnant women can pass these infections to their infants. HIV-HCV coinfection increases the risk of passing on hepatitis C to the baby.
  • Sexually: Both viruses can also be transmitted sexually, but HBV is much more likely than HCV to be transmitted sexually. Sexual transmission of HCV is most likely to happen among gay and bisexual men who are living with HIV.
  • Hepatitis D virus (HDV) is a virus that requires hepatitis B virus (HBV) for its replication. HDV infection occurs only simultaneously or as super-infection with HBV.
  • Hepatitis E is a liver disease caused by infection with a virus known as hepatitis E virus (HEV).The hepatitis E virus is transmitted mainly through the fecal-oral route due to fecal contamination of drinking water. 

Vaccination:

  • Hepatitis A is preventable by vaccine. It spreads from contaminated food or water or contact with someone who is infected.
    • Symptoms include fatigue, nausea, abdominal pain, loss of appetite and low-grade fever.
  • Hepatitis B: Vaccination is the best way to prevent all of the ways that hepatitis B is transmitted. 
  • Hepatitis C: No vaccine exists for HCV and no effective pre- or postexposure prophylaxis is available.
  • Hepatitis D: A vaccine against hepatitis B is the only method to prevent HDV infection.  

Image source: The Hindu