Viral Marker Profile

Acquired Immunodeficiency Syndrome (AIDS) is caused by the Human Immunodeficiency Virus (HIV). HIV Virus is of two types: HIV-1 and HIV-2. HIV-1 is found in AIDS patients, AIDS-related complex patients, and those persons who are at high risk of getting affected by AIDS. HIV virus can be transmitted by sexual contact, exposure to blood or blood products of AIDS-infected patients, or transfer of infection from AIDS-infected mother to the fetus. Most of the cases of HIV-2 infected patients are seen in West Africa, and it is detected in patients who had sexual contact with people of that geographic region. These viruses have the same morphology, overall genomic structure, and ability to cause infection. 

When the patient gets infected with the virus, the virus attacks the immune system called CD4 and combines with antibodies to use them for making a large number of copies inside the body of the patient by replication. During the first few weeks of infection, the amount of virus present and the level of p24 antigen in the blood becomes very high. After another 2-8 weeks, these increased levels start to fall as the body of the infected patient starts producing antibodies against the antigen of the virus. At this time, the HIV virus antibody can be detected in the patient’s blood via tests. The tests should be performed at this brief time because after some time both the levels of antigen and antibody in the blood falls. This will make the detection of virus infection difficult as the initial infection may have been resolved and you may not get a positive result against the infection.

The HIV antibody tests do not detect an HIV infection soon after exposure, before the development of antibodies. Most people produce detectable levels of antibody 3 to 12 weeks after exposure. If someone is screened with an HIV antibody test too soon, the result may be negative despite the fact that the person is infected. For those who are at increased risk of HIV infection, it is important to get this screening test done frequently to check for possible exposure to the virus.

This test is done by ELISA method which is also known as EIA for Enzyme Immunoassay. This test is done to analyze certain proteins which are produced by the body in response to HIV infection. 

Hepatitis C is one of the five hepatitis viruses identified so far, including A, B, D, and E, that are known to cause the disease. HCV causes liver inflammation and damage. It is spread by exposure to contaminated blood, sharing of needles by intravenous drug users, sharing personal items contaminated by blood such as razors, through sex with an infected person, via healthcare occupational exposure, and, less commonly, from mother to baby during childbirth.

It has been observed that most infected people do not see any symptoms (asymptomatic) which makes them unaware of the condition. The acute HCV infection may cause few to mild nonspecific symptoms. This chronic infection may not show any symptoms for a decade or two before causing sufficient liver damage to affect liver function.

Hepatitis C antibody tests are used to screen individuals with risk factors, people who have symptoms associated with hepatitis or liver disease, or those who have been exposed to the virus.

It is possible that the antibody test remains positive even after clearing the infection. So to further diagnose, the test is followed by a hepatitis C RNA test. This test detects the genetic material of the virus. A positive result on the RNA test may indicate the virus is present, the infection has not resolved, and the requirement of treatment.

Many times, a liver panel test is also prescribed by the physician which will include a hepatitis C test to help assess the health of the liver.

HBsAg test detects the presence or absence of Hepatitis B Surface Antigen (HBsAg) in the blood.

Hepatitis B virus is one of the five main hepatitis viruses, referred to as types A, B, C, D and E and is the causative agent of Hepatitis B (infection in the liver). Hepatitis B Surface Antigen (HBsAg) is present on the surface of the Hepatitis B virus (HBV). HBsAg is present in the blood of patients with viral hepatitis B (with or without clinical symptoms).

HBsAg is the first marker appearing in the blood at 6 to 16 weeks following exposure to HBV. In most cases after an acute infection, this virus clears up on its own in 1 to 2 months after the onset of symptoms. But in some people, the virus does not go away and results in chronic infection which over the years may lead to liver damage (scarring or cirrhosis) or liver cancer. Persistence of HBsAg for more than 6 months indicates the development of either a chronic carrier state or chronic HBV infection.