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What is hepatitis? Give its cause and transmission?

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Hepatitis B is caused by the hepatitis B virus (HBV) and is spread through contact with infected blood, semen, and some other body fluids. It can be a sexually transmitted disease (STD). Hepatitis C mostly results from percutaneous infection, occurring when the HCV virus gets under the skin.

Types

hepatitisHepatitis has several different types, but the symptoms of each are similar. Hepatitis can take acute and chronic forms.

The three main types of hepatitis are known as hepatitis A, B, and C. Each is caused by a different virus. All three types can be acute, lasting for 6 months or less, and types B and C can be chronic, lasting for longer.

Each type has different characteristics and is transmitted in different ways, but symptoms tend to be similar.

Hepatitis A

In the United States (U.S.), 1,390 cases of hepatitis A were reported in 2015.

It is often mild, and most people make a full recovery, after which they are immune and therefore protected from the virus in the future. However, if it progresses, symptoms can be severe or life-threatening.

People in parts of the world with poor sanitation are particularly at risk of contracting HAV.

There are safe and effective vaccines that protect against this virus.

Hepatitis B

Hepatitis B can be transmitted when a person:

  • has unprotected sexual intercourse with an infected person
  • shares a needle with an infected person, often for illegal drug or steroid use
  • has a tattoo created with unsterilized needles
  • is accidentally pricked, for example, health workers dealing with sharp objects
  • shares personal items, such as a toothbrush or razor, with an infected person
  • is bitten by someone who is infected

An infected mother can pass the virus on to her infant when breast-feeding.

The liver of a person infected with hepatitis B swells. Severe damage can result.

HBV infection can become chronic. This can lead to complications, including scarring of the liver, or cirrhosis. It can also cause a type of cancer known as hepatocellular carcinoma.

In 2015, 887,000 deaths worldwide were linked to HBV, mostly as a result of complications such as these.

In the U.S., there were 3,370 reported cases of HBV, but the Centers for Disease Control and Prevention (CDC) estimate that the real figure may be around 21,900.

There is not currently a cure for HBV. However, the incidence rate has dropped in countries where the vaccine is available, and this vaccine is 95 percent effective against the infection.

There is a safe and effective vaccine that can protect against HBV.


HCV can lead to liver damage and swelling. Around 1 in 4 people with HCV get cirrhosis, and this can lead to liver cancer.Hepatitis C

Donated blood is now tested for HCV, but people who received organ transplants or blood donations before testing became part of the donation process may be at risk.

Other at-risk groups include healthcare workers who are exposed to sharps, users of intravenous drugs, and infants born to mothers with HCV.

The number of cases of HCV in the U.S. rose nearly threefold between 2010 and 2015 when 2,436 cases were reported. However, the CDC estimate that 33,900 infections occurred in 2015, including those not reported.


Treatment

There is no vaccine to prevent HCV, but treatment can cure it.

Some types and cases of hepatitis can heal without intervention, but sometimes it can progress to scarring of the liver, or cirrhosis.

Hepatitis A

There is no specific treatment for HAV. The doctor will advise the patient to abstain from alcohol and drugs during the recovery. Most patients with hepatitis A will recover without intervention.

Hepatitis B

A patient with HBV needs to rest and abstain completely from alcohol. The doctor may prescribe an antiviral agent called interferon, or other antiviral suppressive therapies.

Hepatitis C

A patient with hepatitis C will be prescribed antiviral agents, with or without ribavirin.

Some directed antivirals and combination therapies are now available to treat the hepatitis C virus based on its subtype. These treatments target viral replication and prevent the virus from being able to reproduce. When taken correctly, the cure rate is very high.

These medications can be expensive, and insurers may have specific criteria for treatment.

Causes

The three most common types of viral hepatitis are all caused by viral infections.

Hepatitis A is caused by consuming food or water infected with the hepatitis A virus (HAV), often while traveling abroad. The virus can also be transmitted through anal-oral contact during sex or by injecting drugs.

Hepatitis B is caused by the hepatitis B virus (HBV) and is spread through contact with infected blood, semen, and some other body fluids. It can be a sexually transmitted disease (STD).

Hepatitis C mostly results from percutaneous infection, occurring when the HCV virus gets under the skin. It is usually spread through injected narcotics, needle-stick injuries, and a lack of infection control in healthcare settings.

HCV cannot be caught from contact with feces, and sexual transmission is less common than in other types.

Alcohol, medicines, obesity, and chemical exposure do not cause types A, B, or C, but they may aggravate inflammation and make symptoms worse.

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