Measles (Morbilli) IgG and IgM

Unsure whether you were vaccinated against measles or have been exposed to an infected person? Measles virus (morbilli) antibody testing shows whether you are protected and helps confirm suspected illness. Measles is one of the most contagious diseases, so knowing your immunity is useful before travel, pregnancy or work with children and patients.

Who the test is for

• adults without vaccination records or unsure whether they have had measles;
• people after contact with an infected person, to establish protection;
• women planning pregnancy;
• healthcare workers, students and people working with children when an employer or doctor requests an immunity check;
• people before travel to countries with measles transmission;
• people with fever, cough, red eyes and rash when a doctor suspects measles.

If someone with measles has difficulty breathing, becomes confused or very sleepy or has seizures, call emergency assistance immediately (194 or 112) and say you suspect measles.

What the test reveals

Measles spreads through the air and is contagious several days before the rash appears. It begins with high fever, cough, a runny nose and red eyes, with a rash several days later, initially on the face and behind the ears. Complications can include ear infection, pneumonia and, rarely, brain inflammation. Two doses of measles, mumps and rubella vaccine (MMR) provide the best protection.

• IgG indicate protection after vaccination or past illness.
• IgM suggest recent infection. They may still be negative in the first three days of rash and are also positive for several weeks after vaccination.

The procedure and preparation

Blood is taken from a vein, taking a few minutes; no special preparation is needed. Mention recent vaccination. If you have fever and rash and suspect measles, do not go directly to any healthcare facility: first phone your doctor, who will arrange examination and testing so you do not infect others, such as pregnant women and infants.

What your result means

• IgG positive: you are protected against measles.
• IgG negative or borderline: protection is unconfirmed. A doctor may recommend vaccination, but not during pregnancy. In someone with two documented vaccine doses, negative IgG does not necessarily mean no protection.
• IgM positive: recent infection or vaccination is possible, as is a false-positive result. Measles must legally be notified to the epidemiological service, so a doctor arranges confirmation at a reference laboratory, usually using PCR on a throat swab or urine.
• IgM negative: does not exclude measles if blood was taken in the first three days of rash.

Thresholds are printed on the report. A doctor interprets results alongside vaccination history, exposure and symptoms.

How to arrange testing

You can have blood taken without an appointment or referral at one of our branches across Croatia (listed under Contact). Prices for all tests and panels are available in the price list. Alongside measles you can also check protection against rubella and mumps.

Frequently asked questions

How can I know whether I was vaccinated against measles?

Your vaccination card, GP or responsible epidemiological service holds vaccination information. If records are unavailable, IgG testing shows protection. A doctor may also vaccinate without testing because an additional dose is not harmful.

I was exposed to someone with measles. What now?

Phone your doctor or epidemiologist. If unprotected, vaccination within three days or immunoglobulin within six days of contact may prevent or lessen disease. Monitor for fever and rash over the next three weeks.

Do I need another vaccination if IgG is negative?

A doctor decides. Without proof of two doses, vaccination is usually recommended. With two documented doses, another is usually unnecessary.

How long does protection last after vaccination?

Two doses provide very good, long-lasting, usually lifelong protection. Past measles also provides lifelong protection.