Positive TB Test on Your Immigration Medical Exam: What Happens Next

A positive TB result is one of the most common reasons applicants panic after the immigration medical exam, and in most cases the outcome is far less serious than it sounds. A positive blood test shows that your immune system has met TB bacteria at some point. It does not mean you are sick or contagious, and it does not by itself stop your form from being completed.

How TB screening works on the exam

TB screening is part of every green card medical exam. Everyone 2 years and older gets an interferon-gamma release assay, known as an IGRA. It is a blood test, drawn at the exam, and it is the test CDC requires civil surgeons to use. Children under 2 are generally not tested unless there is a specific reason: signs or symptoms of TB, or known HIV infection.

If the IGRA is negative and you have no symptoms, TB screening is finished. If it is positive, or if you have signs or symptoms of TB or known HIV infection regardless of the blood test, the next step is a chest x-ray.

Why BCG vaccination doesn’t change the result

Many applicants received the BCG vaccine as children and have been told for years that it makes them “test positive.” That was true of the older skin test. The IGRA used for this exam is not affected by prior BCG vaccination, so a positive IGRA is not a BCG artifact. It usually reflects real, often long-ago, exposure. That is very common for anyone who grew up where TB is widespread, and it is not a judgment about your health or hygiene.

Positive IGRA with a normal chest x-ray: Class B2 latent TB

This is the outcome for most people with a positive test. When the chest x-ray shows nothing suggestive of TB disease and you have no symptoms, CDC’s Technical Instructions classify the result as Class B2, latent TB infection (LTBI).

What that means in practice:

• Your form can be completed. CDC states that treatment is not required to complete adjustment of status for Class B2 latent TB. The civil surgeon records the classification on Form I-693 and finishes the form.
• The result is reported to the health department. Civil surgeons report Class B2 results to the local or state health department. That is a public health step, not an enforcement one. The health department may contact you about evaluation and treatment.
• Latent TB is not contagious. People with latent infection do not spread TB to others.

You can read CDC’s full guidance on its civil surgeon tuberculosis page.

Why treat latent TB anyway

Treatment isn’t a condition of the exam, but it is worth taking seriously. According to CDC, roughly 5 to 10 percent of people with untreated latent TB develop TB disease at some point in their lives, and the risk is higher for people with diabetes, HIV, or medications that weaken the immune system. Treating latent infection greatly reduces that risk.

Modern regimens are shorter than many people expect, often a few months of medication. A primary care doctor or the local health department can advise you, and health departments frequently offer evaluation at low or no cost. You decide the timing; it doesn’t have to happen before you file.

When the x-ray is not normal

Sometimes the chest x-ray shows findings that could suggest TB disease, or the applicant has symptoms such as a persistent cough, fever, night sweats or unexplained weight loss. In those cases the path is different, and it is honest to say it can take longer.

Further testing. You are referred for sputum testing, which usually means collecting samples on several days so a lab can look for TB bacteria and grow cultures. Cultures take several weeks to finalize. The civil surgeon typically cannot complete the TB section of Form I-693 until that evaluation is done.

Possible outcomes. Many abnormal x-rays turn out to be old scarring or something unrelated, and sputum testing comes back clear. If TB disease is diagnosed, CDC’s classification depends on whether it is infectious:

• Infectious TB disease is a Class A condition. It generally must be treated to the point set in CDC’s instructions before the applicant can be medically cleared.
• TB disease that is not considered infectious, or that has been treated, may fall into a Class B category, which is noted on the form rather than blocking it.

The specific rules are detailed and the civil surgeon and health department apply them to your case. What you should know is that an abnormal x-ray starts an evaluation, not a denial, and that TB disease is treatable. If your filing timeline is tight, tell your immigration attorney early so they can plan around the extra weeks.

If you’ve had TB or TB treatment before

A previous diagnosis or treatment usually means the IGRA will be positive again, since it measures immune memory rather than current infection. Bring every record you have: prior test results, chest x-rays and reports, the names of medicines and how long you took them, and any clearance letter. Good records help the surgeon read your x-ray correctly and can prevent extra testing. Our checklist of what to bring covers the other documents.

What the x-ray costs

Chest x-rays are usually priced separately from the exam fee, and some clinics refer you to an outside imaging center. Ask in advance whether the clinic takes x-rays on site, how quickly the reading comes back, and what it costs. Each clinic in our network publishes its price and what it includes on its clinic page; our cost guide walks through typical add-ons.

The bottom line

A positive TB test is a common, well-understood result with a defined next step. In most cases it ends with a normal x-ray, a Class B2 note on the form and a completed I-693. If you’re also concerned about other conditions, see how health conditions affect the exam. For an overview of the whole visit, see our immigration medical exam guide, or find a clinic near you.