About Our Hepatitis A Test
Purpose of the test
The purpose of hepatitis A testing is to determine if a person has been infected by the hepatitis A virus (HAV).
The hepatitis A virus is highly contagious and can be transmitted orally or through fecal material. hepatitis is a condition characterized by inflammation and enlargement of the liver. There are five forms of hepatitis (Hepatitis A, B, C, D, E) of which some may cause only short-term infections (less than 6 months), called acute disease, while others can cause long-term infections known as chronic disease and may persist for a lifetime.
Hepatitis A is typically a sudden, acute infection that lasts a few weeks to several months. In most cases, this virus does not cause chronic infection. In rare cases, though, hepatitis A can be severe and cause liver damage and even liver failure.
This virus is spread through fecal-oral transmission, which means that a person contracts the disease when they ingest traces of the feces (also called stool) of a person infected with hepatitis A. Most often, this is through close personal contact with someone who is infected, primarily due to poor handwashing practices after using the bathroom, caring for an infected individual, through sexual contact, or intravenous drug use. It may also be transmitted through contaminated food or water that is handled by an infected person, contaminated sewage, or ingestion of raw/undercooked shell fish.
A doctor may order hepatitis A testing for several purposes:
- Diagnose current infection: Doctors use hepatitis tests to diagnose the cause of hepatitis in patients with signs and symptoms of this disease.
- Assess immunity: After a person recovers from a hepatitis A infection, they become immune to future infections due to the development of protective antibodies. Hepatitis A testing may show that a person has developed protective antibodies to hepatitis A after recovering from a past infection or because they previously received a hepatitis A vaccination. After recovery, IgG antibodies typically remain in the body for life, providing long-term protection against future hepatitis A infections.
What Does Our Hepatitis A Test Measure?
To determine if viral hepatitis is caused by the hepatitis A virus, hepatitis A testing looks for certain antibodies. Antibodies are substances made by the immune system in response to infection with a virus such as hepatitis A.
The incubation period after the initial exposure is 15 to 50 days (mean time is 30 days). Hepatitis A testing looks for two types of antibodies. Antibodies are part of the body’s protective response to infections. Hepatitis A virus antibodies may be measured by a few different tests:
- Hepatitis A immunoglobulin M (IgM anti-HAV) antibody test: When a person is first infected with hepatitis A, the body produces IgM HAV antibodies, generally 2-3 weeks after the initial exposure, appearing before symptoms begin and remain detectable for about 3–6 months after infection. Elevated titers of IgM HAV antibodies are considered diagnostic of an acute infection.
- Hepatitis A immunoglobulin G (IgG anti-HAV) antibody test: The IgG HAV antibody test detects IgG antibodies that develop later in the course of the disease. IgG antibodies are detectable in the body for life, providing protection against a future hepatitis A virus infection. The IgG anti-HAV test is used to detect past HAV infections and may occasionally be used in identifying developed immunity from a previous infection or vaccination.
- Total hepatitis A antibody test: The total HAV antibody test detects both IgM and IgG antibodies and thus is used to identify both current and past infections.
Although testing the blood for HAV antibodies is the gold standard for identifying a hepatitis A infection, other tests may be ordered that instead look for the genetic material of the hepatitis A virus.
This type of testing, also called nucleic acid amplification testing (NAAT), can detect traces of hepatitis A in a patient’s stool, blood, body fluids, and liver tissue. Molecular testing (NAAT or PCR) for hepatitis A is used primarily in research or public health investigations to confirm outbreaks. It is not commonly used for routine clinical diagnosis.
In many cases, specific hepatitis A testing occurs along with or after blood tests that measure liver function. These tests may include a broad panel of tests, called a liver panel. The measurements in a liver panel can provide information about liver function and inflammation. While these tests can suggest viral hepatitis, they cannot identify the specific virus, which is why antibody testing may be prescribed to confirm the underlying cause.
When Should I Get a Hepatitis A Test?
Doctors often recommend testing for hepatitis based on a patient’s medical history, symptoms, and a physical exam. After exposure to hepatitis A, it may take time for antibodies to develop to levels detectable in a blood test. Because of this, testing immediately after exposure may produce a negative result even if infection occurs later.
Symptoms usually appear 15–50 days after exposure, with an average incubation period of about 28 days. Children with hepatitis A under six years old rarely have symptoms. Symptoms of hepatitis A include:
- Dark urine
- Diarrhea and stool that is gray- or clay-colored
- Fatigue
- Low-grade fever
- Abdominal or joint pain
- Nausea, vomiting, or loss of appetite
- Yellow eyes and skin, also called jaundice
Doctors may recommend hepatitis A testing in patients with symptoms and a known exposure to HAV or an elevated risk of contracting this disease. Testing may still be appropriate even with symptoms if any of the following risk factors are present:
- Travel, especially to Asia, South America, Central America, Africa, and the Middle East
- Using intravenous drugs and the use of illegal drugs
- Living in a nursing home
- Working in industries involving health care, food, or sewage
- Eating raw shellfish, vegetables, and other foods
- Men who have sex with men
- People experiencing homelessness or unstable housing
- People with chronic liver disease
- People working with hepatitis A virus in research laboratories
- People who expect close contact with an international adoptee from a country where HAV is common
If you believe you were recently exposed to hepatitis A, medical care may help prevent infection. Post-exposure prophylaxis (PEP) involves receiving several doses of the hepatitis A vaccine which can provide active and long-term immunity. For individuals who cannot be vaccinated, for infants under 12 months, and for those who need immediate protection, immune globulin (IG) may be administered. These treatments can help prevent illness or reduce its severity. PEP is commonly recommended for people who have had close contact with someone diagnosed with hepatitis A, including household members, sexual partners, or caregivers. A doctor can determine whether vaccination or immune globulin is the most appropriate option.
In patients who develop symptoms of hepatitis A without a known exposure to the virus, doctors may recommend an acute viral hepatitis panel that looks for the most common hepatitis type infections, hepatitis A, hepatitis B, and hepatitis C, in the same blood sample. While there are no specific treatments for hepatitis A, rest, balanced diet, and plenty of fluids may minimize the symptoms. Severe cases may require hospitalization. Few individuals (10%-15%) may have relapsing symptoms for as log as 6 months, but HAV infection is not chronic.
Finding a Hepatitis A Test
How to Get Tested
Hepatitis A testing uses a sample of blood to test for antibodies against the hepatitis A virus. When prescribed by a doctor, a blood sample may be collected in a hospital or other medical setting and sent to a laboratory for analysis. Blood is usually drawn from a vein in the patient’s arm or rarely, the back of the hand.
In addition to tests ordered by a doctor, some laboratories allow patients to purchase hepatitis A testing online. After ordering the test, patients visit a local laboratory to provide a blood sample, and results are typically delivered through a secure online portal within a few days. This option can allow people to access testing without scheduling a doctor’s appointment first.
Can I Take the Test at Home?
At-home sample collection kits are not widely available for hepatitis A. However, many laboratories offer consumer-ordered hepatitis A blood tests that can be purchased online and completed at a local lab without a doctor’s visit.
How Much Does the Test Cost?
When ordered by a doctor, testing for hepatitis A may be paid for by a patient’s health insurance coverage. Health plans vary, so it’s important for patients with health insurance to talk to an administrator about the cost of testing, including any copays or deductibles that may be required.
If a patient doesn’t have health insurance coverage that covers hepatitis A testing, it may be helpful to discuss the cost of testing with a doctor. The total cost can include the office visit, the blood draw, and technician fees in addition to the cost of laboratory testing.
Taking a Hepatitis A Test
Hepatitis A testing is performed on a sample of blood. To obtain the sample, a doctor, nurse, or other health care provider uses a small needle to draw blood from a vein.
Before the Test
Generally, patients do not need to prepare for hepatitis A testing. As with other blood tests, patients should talk to their doctor about any prescription or over-the-counter drugs they are taking, but it is rare to have to adjust medications before a hepatitis A test. Biotin (vitamin B7), certain antibiotics, and NSAIDs (nonsteroidal anti-inflammatory drugs) may interfere with antibody testing.
During the Test
Hepatitis A testing is conducted on a sample of blood that can be collected through a blood draw or by puncturing the skin.
During a blood draw, a health care provider takes a sample of blood from a vein in the patient’s arm. After locating an appropriate vein and cleaning the collection site, a small needle is inserted into the vein, and blood is collected in an attached vial. A blood draw usually takes less than five minutes.
When testing for hepatitis A in infants and young children, a device with a very small needle called a lancet may be used to puncture the skin to collect blood. Once the skin is punctured, a small amount of blood is collected in a tube or vial.
After the Test
After a blood sample is collected, a bandage or piece of gauze may be applied to reduce additional bleeding. Risks of blood collection are minimal, although patients may have light bruising and tenderness where the needle was inserted. There are no restrictions on normal activities after a blood sample is collected.