Anti–Hepatitis E Virus (HEV IgG) Antibody Test – Purpose, Procedure, and Normal Range

Overview

The Anti–Hepatitis E Virus Antibody Test (HEV IgG Test) detects IgG antibodies in the blood that are produced by the immune system in response to the Hepatitis E Virus (HEV).

A positive HEV IgG test means the person was previously infected with Hepatitis E and has developed long-term immunity to the virus. This test is mainly used to confirm past infection, check for immunity, and support public health studies in areas where Hepatitis E is common.

Hepatitis E is a short-term (acute) liver infection caused by the HEV virus, often spread through contaminated food or water, especially in regions with poor sanitation.

What Is the Anti–Hepatitis E Virus (HEV IgG) Test?

The Anti–HEV IgG test measures the presence of IgG antibodies made by your immune system to fight the Hepatitis E Virus.
When a person gets infected, the body’s immune system produces two types of antibodies:

• IgM antibodies: Appear first during active or recent infection.
• IgG antibodies: Appear later, after recovery, and indicate past infection or immunity.

Therefore, this test specifically identifies IgG antibodies, which remain in the blood for years — sometimes lifelong — as a sign of immunity.

Doctors use the HEV IgG test to:

• Confirm previous Hepatitis E infection
• Determine if a person has developed immunity
• Differentiate between new (active) and old (resolved) infection when used along with HEV IgM testing

Where Are HEV IgG Antibodies Produced?

HEV IgG antibodies are produced by B lymphocytes, a type of white blood cell in the immune system.
These cells become active when they detect Hepatitis E virus particles in the bloodstream. Once activated, they produce antibodies to neutralize the virus.

The antibody production mainly occurs in:

• Lymph nodes
• Spleen
• Bone marrow

After the infection is cleared, memory B cells remain in the body, ensuring quick immune defense if the virus reappears.

Main Functions and Importance

The Anti–HEV IgG test doesn’t detect an active infection — instead, it confirms past exposure or immunity.
While the antibodies themselves have no harmful function, they serve an important role in diagnosis, immunity confirmation, and public health monitoring.

Key Uses of the Test:

1. Confirms Past Infection
   Detects if a person had a previous Hepatitis E infection that has now resolved.
2. Identifies Immunity to HEV
   Confirms whether a person has developed protective antibodies against future HEV infection.
3. Public Health and Epidemiology
   Useful for screening populations in areas with high Hepatitis E prevalence to monitor immunity levels.
4. Helps Differentiate Current vs Past Infection
   When combined with HEV IgM, it helps determine if an infection is recent (IgM positive) or old (IgG positive only).

Causes of Low or Negative Levels

Low or undetectable Anti–HEV IgG levels usually mean:

• The person has never been infected with the Hepatitis E virus.
• The test was done too early (within 1–2 weeks of infection), before IgG antibodies developed.
• The immune system is weak or suppressed (for example, due to HIV, certain medications, or chronic illness), preventing adequate antibody production.

Symptoms of Low Levels

Low or negative Anti–HEV IgG levels themselves cause no symptoms.
However, they indicate the person lacks immunity, meaning they are at risk of Hepatitis E infection if exposed.

In such cases, it’s important to take preventive measures, such as maintaining good hygiene and avoiding contaminated water or food in endemic areas.

Causes of High Anti–HEV IgG Levels

High or positive Anti–HEV IgG levels are generally a healthy sign — they indicate that the person has recovered from Hepatitis E and is now immune to reinfection.

Common Causes:

• Past Hepatitis E infection with full recovery
• Immunity developed naturally after infection (long-term or lifelong)
• Occasionally, cross-reactive antibodies due to exposure to related viruses (rare)

Symptoms of High Levels

High Anti–HEV IgG levels themselves do not cause symptoms.
However, if they are the result of a past infection, the person may remember previous symptoms of Hepatitis E, such as:

• Fatigue or tiredness (gradually improving)
• Loss of appetite (returns to normal after recovery)
• Jaundice (yellowing of skin and eyes) that has resolved
• Abdominal discomfort that disappears as the liver heals

A positive IgG result with no IgM means the infection is not active — recovery is complete, and immunity is established.

Reference Ranges

Some laboratories report results simply as:

• “Reactive” (positive) or “Non-reactive” (negative).

Sample Type and Test Method

• Sample Type: Blood (Serum)
• Tube Type: Red-top or Plain Tube (Serum Separator Tube – SST)
• Testing Method: ELISA (Enzyme-Linked Immunosorbent Assay) or CLIA (Chemiluminescent Immunoassay)

No fasting is needed before the test.
The test detects IgG antibodies specific to the Hepatitis E virus antigen.

Test Preparation

• No fasting required.
• Inform your doctor about any recent viral illnesses or vaccinations.
• If your doctor suspects an active Hepatitis E infection, they may also order:
  • HEV IgM Antibody Test (for current infection)
  • Liver function tests (ALT, AST, bilirubin)
  • Ultrasound or other imaging if symptoms persist

When to Consult a Doctor

Consult a doctor if you experience any of the following symptoms suggestive of liver involvement:

• Yellowing of skin or eyes (jaundice)
• Dark urine or pale stool
• Fatigue or weakness
• Abdominal pain or swelling
• Loss of appetite or nausea

A physician — especially a hepatologist or infectious disease specialist — may recommend this test if:

• You recently traveled to an area with known Hepatitis E outbreaks.
• You had symptoms of hepatitis but other tests (Hepatitis A, B, C) were negative.
• You are part of a public health screening program.

Important Word Explanations

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