Where to Get a Chicken Pox Titer Test

Varicella, which is another name for chickenpox, is a very contagious virus infection that is caused by the varicella-zoster virus (VZV). It makes a rash that looks like blisters and is itchy. It starts on the face, scalp, chest, and back and then spreads to the rest of the body. Chickenpox is common in kids, but if you’ve never had it before, you can get it at any age.

Being infected with VZV means that the virus stays dormant in your body for life. It may come back later in life and cause shingles (herpes zoster). Getting chickenpox usually provides lifelong immunity to repeat VZV infections. But some people can get chickenpox more than once or get shingles after having chickenpox as a child.

If you don’t get chickenpox, a blood test called a varicella titer can tell. It checks how many antibodies your body makes in response to a VZV infection. If your titer is positive, it means you are immune to chickenpox well enough. If it’s negative, it means you are likely to get VZV and that you might benefit from getting vaccinated.

Where Can I Get a Chicken Pox Titer Test?

Some options for where you can get a varicella titer test include

• Your doctor’s office – Make an appointment with your primary care physician or pediatrician to order a titer test They will draw your blood sample and send it to a lab for analysis.

• Local clinic – Walk-in clinics like CVS MinuteClinic perform titer tests with no appointment needed. A provider will review your health history and order the appropriate lab test.

• If you don’t have a prescription from your doctor, you can go to a local lab like Quest Diagnostics or LabCorp to get a titer drawn.

• At-home kit – Order a chickenpox titer test kit online from companies like Request A Test and take your own blood sample, Mail it back for lab testing and results

• During pre-employment screening – Some healthcare facilities and schools require proof of varicella immunity for new hires via blood titer testing.

• Hospital or ER – If you have symptoms of an active chickenpox infection, your doctor may order a varicella titer along with other viral tests in the hospital or emergency room.

No matter where you get tested, the procedure for the blood draw is quick and straightforward. The nurse or technician will clean your arm, tie a tourniquet, locate a vein and insert a small needle to collect the blood sample into a vial.

Why Do I Need a Chicken Pox Titer?

There are a few main reasons you may require varicella antibody titer testing:

• To check immunity prior to starting daycare, school, college or a healthcare job. A positive titer proves you’re protected against chickenpox.

• To screen for immunity during pregnancy to decide if the varicella vaccine is needed. Chickenpox in pregnancy can cause complications.

• If you’re unsure if you had chickenpox in the past. A negative titer means you’re still at risk.

• To confirm a chickenpox diagnosis if you develop a rash illness. PCR testing of lesion samples is preferred.

• To investigate potential varicella immunity issues if you get breakthrough chickenpox after vaccination.

• To identify susceptibility to chickenpox after a known exposure so you can receive preventive treatment.

In general, the varicella titer is the most reliable way to verify chickenpox immunity short of documented vaccination records. It provides definitive results on your protection status.

What Does a Chicken Pox Titer Test For?

The varicella titer measures the level of IgG antibodies to VZV in your blood serum. IgG antibodies are made by your immune system to fight off infection after exposure to a virus.

There are two main types of titer tests:

• IgG – This detects antibodies from a current or past chickenpox infection signaling immunity. But it can’t distinguish between antibodies from the natural disease or vaccination.

• IgM – This test reveals a recent primary VZV infection based on elevated IgM levels. But it can’t identify latent antibodies so isn’t used to assess immunity.

The IgG titer is the standard approach for assessing chickenpox protection. A quantitative result above a certain threshold indicates positive immunity.

How Long Do Chicken Pox Titer Results Take?

After your blood is drawn for a varicella titer test, the sample needs to be sent to a medical laboratory for analysis. The timing of results depends on:

• Where your sample was collected – at a lab vs. doctor’s office. Samples drawn directly at a lab can be processed faster.

• The lab location – turnaround times vary.

• Test methodology – ELISA IgG testing is quicker than sending out for viral culture.

• Your insurance – those with insurance tend to get results in 3-5 days while uninsured/self-pay patients may wait up to 10 days.

For routine titer checks, you can generally expect your quantitative IgG results within one week. Speak with the testing provider for a more exact estimate based on their procedures.

If you’re experiencing symptoms of active chickenpox, your doctor may request rush testing which can yield same day results. However, PCR swabs of lesions are better for quick confirmation.

What Do Positive or Negative Chicken Pox Titer Results Mean?

Chickenpox titer test results are reported as positive (immune) or negative (non-immune) along with the quantitative IgG level in IU/mL or units.

Positive results generally indicate:

• An IgG level above the lab’s reference cutoff signifies immunity due to past infection or vaccination. No vaccine needed.

• You’re protected against chickenpox and unlikely to become infected.

• You have latent VZV antibodies in your system that can reactivate in the future to cause shingles.

Negative results typically mean:

• An IgG level below the lab’s reference cutoff indicates no detectable immunity. You’re still susceptible.

• You either never had chickenpox or vaccination. Or your antibody levels have waned over time leaving you unprotected.

• You should receive the age-appropriate varicella vaccine series to prevent potential infection.

Borderline or equivocal results are considered negative and non-immune. It’s impossible to distinguish immunity acquired naturally versus through vaccination based on quantitative IgG levels alone.

How Accurate Are Chicken Pox Titer Tests?

Varicella antibody blood tests are considered highly accurate when performed correctly by a certified clinical laboratory. However, reliability depends partly on the method used:

• ELISA IgG – This technique has a published sensitivity of 95-100% and specificity of 84-97% for detecting natural varicella immunity. It’s less reliable in vaccinated people.

• FAMA IgG – The fluorescent antibody to membrane antigen assay has near perfect sensitivity and specificity but is not widely available.

• PCR – Polymerase chain reaction testing of lesion samples has superior accuracy over blood tests for diagnosing active VZV infection with 99% sensitivity and 94-100% specificity.

False positive varicella titers are rare but can occasionally happen in certain scenarios:

• Recent blood transfusion or IVIG treatment
• History of other herpesvirus infections like mononucleosis
• Cross-reactivity with other viruses

False negatives are more common but may result from:

• Blood draw before full seroconversion occurs
• Improper sample handling leading to IgG deterioration
• Advanced immune deficiency inhibiting antibody production

Overall, the chickenpox titer has excellent performance when administered correctly. It’s considered the gold standard for assessing VZV immunity aside from documented proof of vaccination.

How Often Should I Get a Chicken Pox Titer Test?

For most healthy people who initially test positive, repeat titer testing is unnecessary since chickenpox immunity is believed to be lifelong in those previously infected. However, rechecking titers may be advised:

• Every 5-10 years for healthcare workers to meet employer requirements.

• During each pregnancy to confirm ongoing immunity.

• If completing the 2-dose varicella vaccine series – test 1-6 months after the second dose.

• Before starting immunosuppressive therapy which can reduce antibody levels.

• If you experience a potential chickenpox exposure and are unsure of your status.

• If you develop a rash illness that could be chickenpox.

Otherwise, a one-time titer is usually adequate unless your immunity is in question. By age 20, over 95% of Americans have natural or vaccine-induced immunity to varicella.

The Takeaway

The varicella zoster antibody blood test, also called the chickenpox titer, is a simple way to check for immunity by measuring VZV IgG levels. A positive titer confirms you’re protected against chickenpox while a negative result means you’re still susceptible and should get vaccinated.

Titer testing is widely available through doctor’s offices, clinics, labs and at-home kits making it convenient to get tested. Turnaround for results is typically under one week. This test provides an accurate assessment of immunity when performed correctly so you can take steps to avoid infection if needed.