TAG: GS 3: SCIENCE AND TECHNOLOGY
THE CONTEXT: Kerala’s Malappuram district is experiencing a significant Hepatitis A outbreak, with approximately 8,000 reported cases and 12 deaths.
EXPLANATION:
- Hepatitis A, a highly contagious viral infection, typically spreads through contaminated food and water.
- This outbreak is unusual as it predominantly affects older adults, unlike the usual demographic of children under 15.
- The outbreak may be linked to the use of contaminated food and water resources in the community.
Hepatitis A
- Hepatitis is an inflammation of the liver that is caused by a variety of infectious viruses and noninfectious agents leading to a range of health problems, some of which can be fatal.
- There are five main strains of the hepatitis virus, referred to as types A, B, C, D and E.
- While they all cause liver disease, they differ in important ways including modes of transmission, severity of the illness, geographical distribution and prevention methods.
- In particular, types B and C lead to chronic disease in hundreds of millions of people and together are the most common cause of liver cirrhosis, liver cancer and viral hepatitis-related deaths.
- An estimated 354 million people worldwide live with hepatitis B or C, and for most, testing and treatment remain beyond reach.
Hepatitis A:
- Hepatitis A is a viral infection that affects the liver.
- It is transmitted primarily through the consumption of contaminated water or food that has been contaminated with the feces of an infected person.
- Poor sanitation and hygiene practices, such as inadequate handwashing after using the toilet, can contribute to the spread of the virus.
Hepatitis B:
- Hepatitis B can cause a chronic infection and puts people at high risk of death from cirrhosis and liver cancer.
- It can spread through contact with infected body fluids like blood, saliva, vaginal fluids and semen. It can also be passed from a mother to her baby.
- Hepatitis B can be prevented with a safe and effective vaccine. The vaccine is usually given soon after birth with boosters a few weeks later. It offers nearly 100% protection against the virus.
Hepatitis C:
- Hepatitis C is a viral infection that affects the liver. It can cause both acute (short term) and chronic (long term) illness. It can be life-threatening.
- Hepatitis C is spread through contact with infected blood. This can happen through sharing needles or syringes, or from unsafe medical procedures such as blood transfusions with unscreened blood products.
- Symptoms can include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine and yellowing of the skin or eyes (jaundice).
- There is no vaccine for hepatitis C, but it can be treated with antiviral medications.
- Early detection and treatment can prevent serious liver damage and improve long-term health.
Hepatitis D:
- Hepatitis D is an inflammation of the liver caused by the hepatitis D virus (HDV), which requires HBV for its replication.
- Hepatitis D infection cannot occur in the absence of hepatitis B virus.
- HDV-HBV co-infection is considered the most severe form of chronic viral hepatitis due to more rapid progression towards hepatocellular carcinoma and liver-related death.
- Vaccination against hepatitis B is the only method to prevent HDV infection.
- The routes of HDV transmission, like HBV, occur through broken skin (via injection, tattooing etc.) or through contact with infected blood or blood products. Transmission from mother to child is possible but rare.
- Vaccination against HBV prevents HDV coinfection and hence expansion of childhood HBV immunization programmes has resulted in a decline in hepatitis D incidence worldwide.
Hepatitis E:
- Hepatitis E is inflammation of the liver caused by the hepatitis E virus (HEV). The virus has at least 4 different types: genotypes 1, 2, 3 and 4. Genotypes 1 and 2 have been found only in humans.
- Hepatitis E infection is found worldwide and is common in low- and middle-income countries with limited access to essential water, sanitation, hygiene and health services.
- In these areas, the disease occurs both as outbreaks and as sporadic cases.
- The outbreaks usually follow periods of faecal contamination of drinking water supplies and may affect several hundred to several thousand persons.
- Some of these outbreaks have occurred in areas of conflict and humanitarian emergencies such as war zones and camps for refugees or internally displaced populations, where sanitation and safe water supply pose special challenges.
