THINK ON THESE: Liver’s mortal enemy

What is the mortal enemy of your liver? Hepatitis B, that’s what. And it is caused by hepatitis B virus (HBV) which could be found in a patient’s blood, semen, saliva and other body fluids – yes, just like the dreaded human immunodeficiency virus (HIV).

The bad news is that many Filipinos have the virus – some of whom never know they have it. According to the Department of Health (DOH), about 10% to 16% of Filipino adults suffer from chronic hepatitis B infection. Another source said that at least one out of 10 people is a carrier of the virus.

But before probing further, let’s talk about liver first. It is a large organ with several functions, some of which are related to digestion. The nutrients of the food you eat are absorbed into the intestinal wall, which is supplied with many tiny blood vessels called capillaries.

“These capillaries flow into veins that join larger veins and eventually enter the liver as the portal vein,” explains The Merck Manual of Medical Information. “This vein splits into tiny vessels inside the liver, where the incoming blood can be processed.”

According to the manual, bacteria and other foreign particles absorbed from the intestine are removed, and many nutrients absorbed from the intestine are further broken down so they can be used by the body. The liver performs the necessary processing at high speed and passes the blood, laden with nutrients, into the general circulation.

The liver, if you care to know, manufactures about half of the body’s cholesterol; the rest comes from food. About 80% of the cholesterol made by the liver is used to make bile. The liver secretes bile, which is stored in the gallbladder until it is needed.

The word hepatitis simply means “inflammation of the liver”. Oftentimes, doctors use it to refer to the diseases caused by hepatitis viruses. If a physician tells a patient, “You have hepatitis,” he means that the person has a viral disease caused by a virus that attacks the liver, and not necessarily that he has an inflamed liver.

Not too many Filipinos know that HBV is all too easy to catch. In fact, it is more common than the HIV – yes, the microorganism that causes Acquired Immune Deficiency Syndrome (AIDS) and far more infectious: HBV is 50-100 times more infectious than HIV.

HBV is transmitted the same way as HIV. That is, through sexual intercourse (vaginal, oral, or anal), use of contaminated needles, unsafe blood transfusion, and from mother to her child.

But, mind you, hepatitis B is not transmitted casually. The virus cannot be spread through sneezing, coughing, hugging or eating food prepared by someone who is infected with HBV, according to the World Health Organization (WHO). Also, you cannot get HBV from mosquitoes.

“All viruses which are transmitted by a mosquito must go through a replication before sufficient viruses is available for infection,” assures Professor John S. Tam, of the Department of Microbiology at the Chinese University of Hong Kong. “HBV do not grow in mosquitoes.”

Ninety percent of the people who get hepatitis B recover spontaneously with their body’s defenses. “The remaining 10 percent who maintain the infection for six months or longer and who do not produce an effective antibody response are considered chronic carriers,” explains Dr. Ernesto O. Domingo, a physician who received the 2013 Ramon Magsaysay Award for his work in medical science.

Hepatitis can be acute (short-lived) or chronic (lasting at least six months). “Acute hepatitis can produce anything from a flu-like illness to fatal liver failure,” explains the Merck manual.

Though much less common than acute hepatitis, chronic hepatitis can persist for years, even decades. “In most people, it is quite mild and does not cause significant liver damage,” the Merck manual states. “In some people, though, continued inflammation slowly damages the liver, eventually producing cirrhosis (severe scarring of the liver), liver failure, and sometimes liver cancer.”

So far, medical scientists have discovered six different kinds of hepatitis: A, B, C, D, E, and G. A different virus causes each of these. Five types cause disease in the liver while one (hepatitis G) lives in the blood without causing any apparent illness. All five disease-carrying viruses are responsible for more than 98 percent cases of viral hepatitis.

Unknowingly, “hepatitis viruses cannot live outside a cell,” says Prof. Tam. “They only come alive when they are given the right conditions such as the necessary nutrients from inside a cell. At room temperature, they do not last very long – maybe 10 minutes. Once the blood dries, infectivity decreases.”

“Hepatitis B virus is the most common cause of liver cancer around the world,” says Professor Mei-Hwei Chang, chairman of the Department of Pediatrics at the National Taiwan University Hospital in Taipei. “Although hepatitis C virus is the most prevalent cause of liver cancer in some countries where HBV infection is not prevalent, HBV is still the most prevalent cause worldwide.”

What are the signs? “Sometimes, people infected with HBV have what looks like the flu, with symptoms including loss of appetite, nausea and vomiting, fever, and weakness,” wrote Dr. Alan Berkman, author of Hepatitis A to G: The Facts You Need to Know About All the Forms of This Dangerous Disease. “They may also develop symptoms more directly related to their livers: abdominal pain, dark urine, jaundice.” Jaundice is the yellow discoloration of the skin and the whites of the eyes.