By Dr. Amaresh Kumar Sahoo, Assistant Professor,Department of Applied Sciences, IIIT Allahabad, India; Email:asahoo@iiita.ac.in
The 2020 Nobel Prize in Physiology or Medicine is awarded to Prof.Harvey J. Alter, Prof.Michael Houghton and Prof.Charles M. Rice “for the discovery of Hepatitis C virus“. This is a blood-borne disease that has been the reason for more than a million deaths and caused a major health problem around the globe. The viral infection is the leading cause of different types of Hepatitis, with some of its forms that remained dormant for years until developed life-threatening symptoms. Much appreciation to Prof. Harvey J. Alter, Prof.Michael Houghton and Prof.Charles M. Rice for their groundbreaking discoveries that led to the identification of causative agent of this blood-borne disease, a novel virus, Hepatitis C Virus. The committee members of the Nobel Assembly at Karolinsky Institute in Stockholm, Sweden issued several statements regarding the revolutionary impact of this pioneering discovery in understanding the causes and cure for chronic Hepatitis. They added, “for the first time in the history, the disease can now be cured and it also raises hope of eradicating the disease caused by Hepatitis C virus from the world population”.
Hepatitis has been a serious threat to human health from ancient times. Hepatitis causes a liver infection that may have serious health issues. This virus is having a longer incubation period within the human body- the time between first exposure and start of the disease – itvaries from 14 to 80 days, with an average incubation period of 45 days.
Infection sources of liver dysfunction and other health issues like fatigue and vomiting. This also causes jaundice characterized by yellow pigmentation of eyes and skin. Moreover, it may cause acute and chronic infections to lead to serious health complications like liver cancer or Cirrhosis. The cases of Hepatitis were seen upsurge rapidly since 1960 due to the increased number of surgeries and multiple blood transfusions. In World Health Organization (WHO) report around 1.34 million deaths mainly due to Hepatitis C virus infections were reported in 2015, which is approximately 63% increase in cases since 1990. Originally only Hepatitis Type A and Hepatitis Type B were known. The discovery of a vaccine for Hepatitis type B partially reduced the risk but chronic liver damage and liver cancer persisted. In the 1970s, Harvey Alter, a senior investigator for the National Institutes of Health in Maryland discovered a new type of Hepatitis Virus while studying the blood transfusion among the patients at the U.S. National Institutes of Health. Later, Michael Houghton, a British Scientist while working for a pharmaceutical firm Chiron then, dedicatedly put the strenuous effort in isolating the genetic sequence of the virus and given a name to this unknown virus as Hepatitis C Virus in 1989. Subsequently, Professor Charles M. Rice consistently worked at the Center for the Study of Hepatitis C as Scientific and Executive Director from 2001 to 2018 at Rockefeller University at New York and provided the final pieces of evidence stating that Hepatitis C Virus alone could cause Hepatitis. This is a RNA virus, which is having envelope glycoproteins such as E1 and E2 on the outside of the viral surface. The hepatitis C virus (HCV) causes hepatitis C, which is contagious in nature, and an infected person may transmit it to a non-infected person via blood contact. Therefore, the transfusions of unscreened blood and blood products or unsterilized medical setups have been found to be the major route of the transmission of HCV infections. It would be mentioned here that different genetic variations (genotypes) are present in the case of HCV strains. Thus, the prescription of the medicines is done based on the genotype of infection of HCV. Use of combination therapy of recombinant interferon (IFNα) and the nucleoside analogue ribavirin was being recommended initially. However, several side effects and risks factors limit their widespread usages. In this line of interest, the development of drugs was proposed by specifically targeting the viral RNA-dependent RNA polymerase or other vital proteins.
The work of these three Nobel Laureates distinctively characterizes this form of Hepatitis from other clinical entity and found to be caused by an RNA virus of the Flavivirus family, termed as Hepatitis B virus. It is a milestone achievement that paved the way for the introduction of a new screening technique and an effective antiviral drug in medicine that could dramatically reduce the risk of Hepatitis C infection.
Ref : https://www.nobelprize.org/prizes/medicine/2020/summary/#main-navigation-js