Molecular detection of hepatitis D virus (HDV) is used for laboratory confirmation of the virus.
Hepatitis D, also known as Delta hepatitis, is a viral infection caused by the hepatitis D virus (HDV). HDV is considered a defective virus because it requires the presence of the hepatitis B virus (HBV) to replicate and cause disease. Therefore, individuals infected with HDV often have concurrent HBV infection, which is known as co-infection, or they acquire HDV infection on top of an existing HBV infection, which is called superinfection.
Transmission: HDV is transmitted primarily through blood-to-blood contact, like HBV. The most common routes of transmission include sharing contaminated needles among intravenous drug users and from mother to child during childbirth. It can also be transmitted through sexual contact with an infected individual and rarely through blood transfusions or organ transplants.
Prevalence: Hepatitis D is considered a global health concern, but its prevalence varies widely among different regions. It is more prevalent in areas where HBV is endemic, such as sub-Saharan Africa, the Amazon Basin, the Middle East, Central Asia, and the Mediterranean region. In these areas, up to 30% of HBV-infected individuals may also be co-infected with HDV.
Disease progression: HDV can cause both acute and chronic hepatitis. The clinical presentation of HDV infection is similar to HBV infection, but it tends to be more severe. Acute hepatitis D can range from mild symptoms to a fulminant form of hepatitis that can lead to liver failure and death. Chronic hepatitis D occurs when the infection persists for more than six months, and it can progress to advanced liver disease, including cirrhosis and hepatocellular carcinoma (liver cancer).
Diagnosis: The diagnosis of hepatitis D involves detecting HDV-specific antibodies and viral RNA in the blood. Serological tests are used to detect antibodies against HDV. Molecular tests such as PCR (polymerase chain reaction) are used to detect HDV RNA, which confirms the presence of active infection.
Treatment: There is no specific antiviral treatment for acute hepatitis D. Supportive care is provided to manage symptoms and prevent complications. For chronic hepatitis D, pegylated interferon-alpha is the mainstay of treatment. Interferon therapy can suppress viral replication and potentially improve liver function.
Prevention: Vaccination against HBV is the most effective way to prevent hepatitis D infection, as HDV requires HBV to replicate. The hepatitis B vaccine is recommended for all individuals, particularly those at high risk, such as healthcare workers, people who inject drugs, and individuals with multiple sexual partners.
