Nobel Prize in Physiology or Medicine, 2020 is jointly awarded to American researchers Harvey J. Alter and Charles M. Rice and British-born scientist Michael Houghton for the discovery of Hepatitis C virus which is a major contributor to morbidity and mortality, causing over a million deaths a year globally. In this context it is necessary to study about the disease in detail.
- Geographical distribution
- Globally, an estimated 71 million people have chronic hepatitis C virus infection.
- According to WHO estimates in 2016, approximately 3,99,000 people died from hepatitis C, mostly from cirrhosis and hepatocellular carcinoma (primary liver cancer).
- The most affected regions are the WHO Eastern Mediterranean Region and the WHO European Region, with an estimated prevalence in 2015 of 2.3% and 1.5% respectively.
- Prevalence of HCV infection in other WHO regions varies from 0.5% to 1.0%.
- HCV infection can be concentrated in certain populations. E.g. 23% of new HCV infections and 33% of HCV mortality is attributable to injecting drug use.
- There are multiple strains (or genotypes) of the HCV virus and their distribution varies by region. However, in many countries, the genotype distribution remains unknown.
- The incubation period for hepatitis C ranges from 2 weeks to 6 months.
- Following initial infection, approximately 80% of people do not exhibit any symptoms.
- Those who are acutely symptomatic may exhibit fever, fatigue, decreased appetite, nausea, vomiting, abdominal pain, dark urine, grey-coloured faeces, joint pain and jaundice.
It is a bloodborne virus. It is most commonly transmitted through:
- injecting drug use through the sharing of injection equipment
- the reuse or inadequate sterilization of medical equipment, especially syringes and needles in healthcare settings
- the transfusion of unscreened blood and blood products
- sexual practices that lead to exposure to blood
- HCV can also be transmitted sexually and can be passed from an infected mother to her baby
It is not spread through breast milk, food, water or casual contact such as hugging, kissing and sharing food or drinks with an infected person.
Testing and diagnosis:
- As new HCV infections are usually asymptomatic, few people are diagnosed when the infection is recent.
- In those people who go on to develop chronic HCV infection, the infection is also often undiagnosed because it remains asymptomatic until decades after infection when symptoms develop secondary to serious liver damage.
HCV infection is diagnosed in 2 steps:
- Testing for anti-HCV antibodies with a serological test identifies people who have been infected with the virus.
- If the test is positive for anti-HCV antibodies, a nucleic acid test for HCV RNA is needed to confirm chronic infection.
- After a person has been diagnosed with chronic HCV infection, he or she should have an assessment of the degree of liver damage (fibrosis and cirrhosis) either by liver biopsy or through a variety of non-invasive tests.
- The degree of liver damage is used to guide treatment decisions and management of the disease.
- A new infection with HCV does not always require treatment, as the immune response in some people will clear the infection.
- However, when HCV infection becomes chronic, treatment is necessary.
- WHO recommends therapy with pan-genotypic direct-acting antivirals (DAAs) which can cure most persons with HCV infection.
- The treatment duration is usually 12 to 24 weeks depending on the absence or presence of cirrhosis.
- WHO recommends treating all persons with chronic HCV infection over the age of 12 with pan-genotypic DAAs.
Unlike hepatitis B, it is not sexually transmitted. There is no known vaccine for hepatitis C. For people infected with the hepatitis C virus, WHO recommends:
- education and counselling on options for care and treatment;
- immunization with the hepatitis A and B vaccines to prevent coinfection from these hepatitis viruses and to protect their liver;
- early and appropriate medical management including antiviral therapy;
- regular monitoring for early diagnosis of chronic liver disease.
In children aged less than 12 years with chronic HCV infection, WHO recommends:
- deferring treatment until 12 years of age
- treatment with interferon-based regimens should no longer be used.
India and Hepatitis C:
- The states which have seen a very great rise in the incidence of Hepatitis C are Punjab, Haryana and Western UP.
- There are villages in these regions in which almost 80% of the population is suffering from Hepatitis C.
- The exact reason for such high prevalence is unknown.
- There are two large groups in India which are actually being screened:
Pregnant women, who are undergoing screening for all 3 viruses Hepatitis B, C and HIV.
Those who donate blood for transfusions.
- The price of treatment of HCV has become a global concern with unscrupulous patents hindering access. Gilead’s Sofosbuvir is very expensive compared to the generic versions.
- High cost of diagnosis – At present, an individual has to pay almost Rs 15,000 for the diagnosis which is a huge amount for a poor person.
- Screening for Hepatitis C is a problem.
- Even when a patient has been diagnosed, the disease is not taken seriously as there are no instant threatening symptoms. Problems may start surfacing 20 years after the infection in the form of liver cirrhosis or liver cancer.
- HCV is more dangerous than HIV because of its longevity and an infected person might be unaware about it and infect others.
- Hepatitis C is India’s hidden epidemic. Comment.
Approach to the answer:
- Write why the disease is in news
- Write about it and its symptoms
- Write its status in India
- Write the challenges faced in tackling it