•What you must know
By Doris Obinna
Hepatitis means inflammation of the liver that is caused by a variety of infectious viruses and non-infectious agents leading to a range of health problems, some of which can be fatal. 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.
According to the World Health Organisation (WHO), there are five 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.”
A Professor of Medicine, Gastroenterology and Liver Unit, Faculty of Clinical Sciences, College of Medicine, University of Ibadan, Jesse Otegbayo, explained: “The liver is an essential organ in the body and without it, there cannot, indeed, be life. As the first major metabolic site for ingested foods and other substances after intestinal absorption, it is exposed to various antigens from food, microbes or bugs and microbial degradation products, endotoxins, xenobiotics, drugs as well as other substances, which at times are injurious to the liver itself.
“Even though, medically, the liver is regarded as the workhorse or powerhouse and the seat of most and major metabolic processes in the body, it has been associated with divination! In ancient Greece, the Babylonians used it as a form of divination to make omens which is central to the practice of hepatoscopy or hepatomancy.
“This is also corroborated in the Holy Scriptures in Ezekiel 21:21 (NKJV) ‘For the King of Babylon stands at the parting of the road, at the fork of the two roads, to use divination, he shakes the arrows, he consults the images, he looks at the liver.’ The liver at various times has also been regarded as the seat of life, human feelings, and emotion, love, and courage: hence the saying ‘lily-livered’ to symbolise cowardice.”
According to the Professor, the liver is appropriately ascribed the appellation of the body work horse or powerhouse of the whole body, because it is known scientifically to play crucial roles in carbohydrate, fat, protein, vitamins, and mineral metabolism, including drug detoxification/ metabolism, energy homeostasis, production of bile, cholesterol synthesis, regulation of amino acids, iron storage, detoxification of ammonia into urea, regulation of blood clotting, immunity, and many others. In fact, it is known to perform over five hundred functions in the body.
He said: “As a result of this enormous metabolic task, the liver enjoys a rich supply of blood amounting to one-quarter; 25 per cent of the blood pumped from the heart per minute, that it is the cardiac output, higher than 15-20 per cent for the brain, in spite of constituting just two and a half percent; 2.5 per cent of the total body weight. It is also known to be the largest solid organ in the human body.
“In fact, it is one organ that receives dual blood supply, via hepatic arteries and the portal vein, to ensure adequate supply of oxygen, all because of its vital functions. Consequent upon this huge inflow of blood into the organ, it is in constant contact with all the various elements that are transported in the blood which invariably includes disease causing organisms and chemical compounds, some of which are injurious to it, and thus causing liver diseases.”
Diseases of the liver
Otegbayo continued: “The major aetiologic factors for liver diseases are parasites, bacteria, viruses, excessive alcohol consumption, drugs, toxins/aflatoxins, autoimmunity, diabetes, obesity, granulomas and rarely some monogenetic syndromes. Among the major aetiologic factors of liver disease, the hepatitis viruses, collectively known as hepatotropic viruses are responsible for about ninety per cent of causation of liver diseases.
“These viruses form an alphabet soup according to the time they were discovered. There are therefore hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and hepatitis E virus (HEV).
“Other virus that affects the liver cause milder disease and are called non-hepatotropic viruses. The difference between the two groups is mainly in the severity of the disease they cause in the liver. While hepatotropic viruses bite the liver and lick other organs, non-hepatotropic viruses lick the liver and bite other organs. Collectively, they cause viral hepatitis, which is defined as virally mediated liver inflammation.”
Viral hepatitis (HBV)
“Etymologically, the word hepatitis evolved from the Greek word for liver, hepar, and the suffix, itis, means inflammation. Hepatitis, therefore, simply means inflammation of the liver. Viruses are microorganisms that are known to be smaller than bacteria, they multiply and spread rapidly. When hepatitis is due to a viral infection, it is known as viral hepatitis. Viral hepatitis is therefore, a diffuse inflammation of the liver caused by viruses.
“All the hepatotropic viruses have been tested and found to be present in abundance in Nigerian patients with various health conditions, pregnancy, and even the apparently healthy individuals Hepatitis B virus, however, has the most devastating effect in our environment, with a capacity to deliver a toxic and fatal sting on the liver,” he explained.
Most common cause
According to WHO, the most common causes of cirrhosis worldwide are related to viral hepatitis, alcohol, and non-alcoholic fatty liver disease. Hepatotropic viruses are the aetiological factor in most cases of acute hepatitis, but drug-induced liver injury increasingly accounts for a significant proportion of cases.
Global burden
Otegbayo disclosed that the burden of HBV is huge, and it is the most studied of the hepatotropic viruses. “It has a global distribution and the WHO estimates that about 2 billion people have markers of infection worldwide, and it accounts for about 900,000 deaths each year due to complications with over 250 million chronic carriers. The highest prevalence is found in sub-Saharan Africa and Southeast Asia.
“In Nigeria the prevalence rate of HBV ranges from six per cent to 25 per cent and more than 20 million people are living with hepatitis B, C, or both; yet more than 80 per cent of the people who have the disease do not know their status, according to some estimates.”
Transmission
“The transmissible form of HBV is found in all body fluids, such as blood, semen, saliva, sweat, urine, and bile, among others. The most effective means of transmission, however, is blood and blood products. Other channels are sexual contacts, saliva, and organ transplantation. Because the organism is highly infectious, only a small quantity of fluid is required to transmit the infection, and in fact, HBV is about a hundred times as infectious as the dreaded HIV virus and could survive for as long as six weeks on a dry surface. It can also resist the temperature of boiling water for 1 hour and still retain its infectivity.
“Generally, transmission of HBV could be vertical or horizontal. Vertical transmission is from mother to child, while horizontal transmission is from person to person. In Africa, HBV is significantly transmitted horizontally during childhood because of contact with exudates from open sores and contact sports. In Nigeria, among blood donors at the University College Hospital, Ibadan, the most common risk factors, and the source of infection through bloodletting were scarification and indiscriminate injections.
“There are individuals who are at a higher risk of acquiring HBV infection; these are health workers especially gastroenterologists, contacts of infected persons, men who have sex with men (MSM), infants of infected mothers, multiple sexual partners, and those with sexually transmitted infections, among others.
“Also, in a study of jaundice in pregnancy at the University College Hospital, Ibadan, viral hepatitis accounted for about two-thirds of all the cases of jaundice, and HBV was responsible for about a third of them. The infection was found to contribute adversely to foetal outcomes, with higher risks of preterm deliveries, intrauterine foetal deaths, and early neonatal deaths.
“Maternal viral hepatitis could lead to neonatal hepatitis or transmission of the infection to the neonate at birth or sometimes during intrauterine life. This calls for screening of all pregnant women for HBV during antenatal care, and early administration of HB immunoglobulin to the newborn of HBV positive mothers, within 72 hours of birth. Intravenous drug use (IVDU), though significant in affluent nations, through the sharing of needles, does not appear to be a significant route of transmission in developing nations.”
Prevention
“Some types of hepatitis are preventable through vaccination. A WHO study found that an estimated 4.5 million premature deaths could be prevented in low and middle income countries by 2030 through vaccination, diagnostic tests, medicines and education campaigns. WHO’s global hepatitis strategy, endorsed by all WHO member states, aims to reduce new hepatitis infections by 90 per cent and deaths by 665 per cent between 2016 and 2030.”
Remedies
For people who want to maintain liver health, WHO recommends hepatitis testing, treatment if diagnosed, and vaccination against hepatitis B. “Reducing alcohol consumption, achieving a healthy weight, and managing diabetes or hypertension also benefit liver health.”