Hepatitis D

Hepatitis D, also known as “delta hepatitis,” is a liver infection caused by the hepatitis D virus (HDV). Hepatitis D only occurs in people who are also infected with the hepatitis B virus. Hepatitis D is spread when blood or other body fluids from a person infected with the virus enters the body of someone who is not infected. Hepatitis D can be an acute, short-term infection or become a long-term, chronic infection. Hepatitis D can cause severe symptoms and serious illness that can lead to life-long liver damage and even death. People can become infected with both hepatitis B and hepatitis D viruses at the same time (known as “coinfection”) or get hepatitis D after first being infected with the hepatitis B virus (known as “superinfection”). There is no vaccine to prevent hepatitis D. However, prevention of hepatitis B with hepatitis B vaccine also protects against future hepatitis D infection.

Transmission and Exposure

HDV is mainly transmitted through activities that involve percutaneous (i.e., puncture through the skin) and to a lesser extent through mucosal contact with infectious blood or body fluids (e.g., semen and saliva), including:

  • Sex with an infected partner;
  • Injection-drug use that involves sharing needles, syringes, or drug-preparation equipment;
  • Birth to an infected mother (rare);
  • Contact with blood from or the open sores of an infected person;
  • Needle sticks or exposures to sharp instruments;
  • Sharing items (e.g., razors and toothbrushes) with an infected person.
  • HDV is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, hand holding, coughing, or sneezing.
Who are at Risk?

The following populations are at increased risk for becoming infected with HDV:

  • People chronically infected with HBV
  • Infants born to mothers infected with HDV
  • Sex partners of persons infected with HDV
  • People who inject drugs
  • Household contacts of people with HDV infection
  • Health care and public safety workers at risk for occupational exposure to blood or blood-contaminated body fluids
  • Hemodialysis patients
Signs and Symptoms

HDV causes infection and clinical illness only in HBV-infected people. The signs and symptoms of acute HDV infection are indistinguishable from those of other types of acute viral hepatitis infections. These include:

  • Fever
  • Fatigue
  • Loss of appetite
  • Nausea
  • Vomiting
  • Abdominal pain
  • Dark urine
  • Clay-colored bowel movements
  • Joint pain
  • Jaundice

These signs and symptoms typically appear 3–7 weeks after initial infection.

Diagnosis and Treatment

Because cases of hepatitis D are not clinically distinguishable from other types of acute viral hepatitis, diagnosis can be confirmed only by testing for the presence of antibodies against HDV and/or HDV RNA. HDV infection should be considered in any person with a positive hepatitis B surface antigen (HBsAg) who has severe symptoms of hepatitis or acute exacerbations.

No treatment is available for HDV infection specifically. Pegylated interferon alpha has shown some efficacy, but the sustained virologic response rate (a measure of viral clearance) is low (25%) (12). New therapies are being evaluated (12). In cases of fulminant hepatitis and end-stage liver disease, liver transplantation may be considered.

Prevention

Although no vaccine is available for hepatitis D, vaccination with the hepatitis B vaccine can protect people from HDV infection.