Hepatitis Beat the Virus
Hepatitis is a ticking time bomb for liver health, with millions unknowingly at risk. However, it can be effectively managed through informed action. Hepatitis Day serves as a call to protect future generations from a preventable epidemic.
By Dr Suneela Garg / Dr Arvind
Viral hepatitis, a significant public health burden in India, demands a holistic approach for prevention and control. The government of the National Capital Territory (NCT) of Delhi, recognising the importance of this issue, officially declared December 4 as Hepatitis Day in 2001. Since then, the Institute of Liver and Biliary Sciences (ILBS) in Vasant Kunj, New Delhi, has taken the lead in organising annual events to raise awareness. These events feature poster competitions, family counselling sessions, public lectures by celebrities, exhibitions, and free blood screening camps, all aimed at educating the public on prevention, from improving sanitation and vaccination to safer lifestyle choices. The 2024 theme, Prevent Hepatitis: Act Now, reflects the urgency of addressing this pervasive issue.
Hepatitis Viruses: A Comprehensive Overview
Hepatitis viruses, which cause inflammation of the liver parenchyma, include five major types: A, B, C, D, and E. Each type has distinct transmission methods, health implications, and prevention strategies.
Hepatitis A virus (HAV) is a single-stranded, non-enveloped virus belonging to the Picornaviridae family. It is classically spread via the faecal-oral route and is closely related to poor hygienic and sanitary conditions in the community. The clinical spectrum of the infection varies widely and is closely linked to the age of the infected individual. With increasing age (from over 6 years to adulthood), the probability of developing clinical symptoms related to hepatitis escalates significantly. HAV is considered endemic in India, and most of the population is infected asymptomatically in early childhood, leading to lifelong immunity. Though HAV infection is typically mild and subclinical in most cases, mortality increases if it leads to liver failure or occurs in the presence of an underlying chronic liver disease.
Prevention of HAV infection: As the faecal-oral route is implicated in the transmission of HAV, adequate disposal of sewage, supplying safe and pure drinking water, and improving personal hygiene practices help reduce the spread of HAV. The Indian Academy of Paediatrics recommends two doses of any licensed vaccine, to be given six months apart, to children aged one year or older. In immunocompromised individuals and for post-exposure prophylaxis (PEP), inactivated vaccines are preferred.
Hepatitis B virus (HBV) is a double-stranded DNA virus belonging to the family Hepadnaviridae. HBV is transmitted via permucosal or percutaneous exposure to infected body fluids or blood products and has an incubation period averaging around four months. Transmission occurs vertically from an infected mother to child, horizontally (e.g. between children in a household), sexually, and parenterally (e.g. via blood transfusions, intravenous drug abuse, etc.).
The spectrum of HBV infection ranges from acute to chronic, depending on the duration of persistence of HBV surface antigen (HBsAg) in the serum. The majority of patients with acute infection remain asymptomatic, and only 30 per cent develop icteric hepatitis. The incidence of fulminant hepatic failure remains low (0.1-0.5 per cent). When HBsAg persists in the serum for over six months, the patient is diagnosed with chronic HBV infection.
Prevention of HBV infection includes vigilant screening of blood and blood products and routine testing of tissue and organ donors. Providing needle exchange programmes and harm reduction advice to those actively involved in intravenous drug use (IVDU), and educating about the usage of barrier contraceptives (e.g. condoms) and promoting safe sexual practices are imperative in preventing HBV infection. Mother-to-child transmission can be prevented by routine screening of mothers and providing PEP to all infants born to infected mothers. A PEP regimen consisting of hepatitis B immunoglobulin (HBIg) and vaccination can prevent infection in more than 90 per cent of cases.
An effective vaccination programme plays a crucial role in preventing HBV infection and is known to decrease the incidence of chronic liver disease and hepatocellular carcinoma (HCC). In 1992, WHO recommended that all countries incorporate HBV vaccination into their routine immunisation programmes. The vaccination is administered in a three-dose schedule (0, 1, and 6 months) and aims to achieve a protective anti-HBs titre of >10 mIU/ml.
Hepatitis C virus (HCV) is an enveloped, single-stranded RNA virus belonging to the family Flaviviridae. It is divided into six major genotypes, with genotype 1 being the most prevalent globally (46 per cent), followed by genotype 3 at 22 per cent, and genotypes 2 and 4 at 13 per cent each. The genotypic distribution of HCV in India suggests that genotype 3 is the most common (61.8 per cent), followed by genotype 1 (31.2 per cent). Genotypes 2, 4, 5, and 6 have been detected in 0.05-4.5 per cent of cases. Globally, HCV is the predominant cause of post-transfusion hepatitis. The seroprevalence of HCV in the general population of India has been reported to range from 0.22 per cent to 1.8 per cent.
HCV is spread via percutaneous or permucosal exposure to infectious blood or blood products. The high-risk groups for HCV infection include individuals receiving multiple blood transfusions (e.g. thalassemics), those engaging in unsafe sexual practices, IVDU, patients on haemodialysis (HD), healthcare workers, and transplant recipients. Preventing HCV requires a multipronged approach, which includes educational counselling about the modes of transmission directed not only at high-risk groups but also the general population, active screening of high-risk groups to detect HCV infections, and prompt treatment with direct-acting antivirals (DAAs) to decrease the reservoir pool.
Hepatitis D virus (HDV) is an RNA virus that encodes hepatitis D antigen (HDAg), which, along with the viral RNA, requires encapsidation with HBsAg. A replicative HDV infection requires the presence of HBV infection. HDV is spread via the parenteral route and can be acquired as either a co-infection (simultaneously with HBV) or a superinfection (on a pre-existing HBV infection). HDV infection is infrequent in India, and preventive strategies are the same as those for HBV.
Hepatitis E virus (HEV) is a positive-stranded RNA virus, non-enveloped, and belongs to the family Hepeviridae. HEV is deemed the most frequent cause of acute viral hepatitis (AVH) in India. HEV is classified into four major genotypes (1-4), with genotype 1 being the most common in India.
HEV is primarily spread via the faecal-oral route, but unlike other viruses spread by this route (e.g. HAV), person-to-person transmission is relatively low. Other modes, such as vertical and parenteral transmission, have been documented, though their clinical implications remain debatable.
HEV is responsible for a significant proportion of acute viral hepatitis in India, and several epidemics related to HEV have been reported. HEV infection not only causes ALF but also worsens liver function in patients with underlying chronic liver disease, a condition termed acute-on-chronic liver failure (ACLF). During epidemics, women in the late trimester of pregnancy are infected more frequently (12-20 per cent) than non-pregnant women and men (2-4 per cent). The frequency of ALF is also significantly higher in pregnant women (15-60 per cent) compared to non-pregnant women, although pregnancy per se is not considered a poor prognostic factor once ALF develops.
Prevention of HEV infection: Provision of safe, clean drinking water, proper sewage disposal, and maintaining good personal hygiene (e.g. hand washing) are essential to control HEV outbreaks.
Viral hepatitis poses a major healthcare burden in India, and strategies to effectively control the problem are needed. Viruses transmitted via the faecal-oral route (HAV and HEV) can be effectively controlled by ensuring proper sanitary conditions and providing clean and safe drinking water. Preventive strategies for HBV and HCV include active screening of high-risk groups, stringent public surveillance programmes, and educational curricula targeting not only high-risk groups but also the general population. Effective vaccines are now being employed in preventive strategies against viral hepatitis, and coupled with other measures, they can help tackle the burden of viral hepatitis in India.
Thus, India’s integrated approach, combining vaccination, sanitation, and public education, offers a robust framework for tackling viral hepatitis. With sustained efforts, the country can significantly reduce the health and economic impact of this disease.
(The authors are Ex-Sub Dean MAMC, Professor of Excellence, Chair NIHFW (PAC), Secretary General Sound Hearing, Member Lancet Commission, and Head Paediatrics, Apollo Hospitals, Noida)