Rubella virus infection is especially dangerous for a woman during pregnancy. This disease can cause severe developmental abnormalities in the unborn child. Therefore, doctors recommend expectant mothers to test for antibodies to rubella, Rubella virus. This study is also prescribed for women planning a pregnancy to determine if vaccination is necessary. The test transcript may indicate: "Anti-Rubella-IgG positive." What does it mean? Does this indicate immunity to rubella? We will answer these questions in the article.
What is rubella?
Rubella is an infectious disease caused by the Rubella virus. Most often, this pathology is noted in children. However, rubella also affects adults, they suffer this disease especially hard. The virus is transmitted by airborne droplets, as well as through the placenta from mother to fetus.
The first signs of the disease are preceded by an incubation period, it lasts from 11 to 24 days. Then the patient's general state of health worsens: the temperature rises, weakness, aching in the joints and an increase in lymph nodes occur.
On the second day of the disease, small rashes of red color appear on the body. Spots cover the face, lower back and limbs. Recovery usually occurs 7 to 10 days after the onset of the first symptoms. After the disease, a person develops a persistent lifelong immunity to the Rubella virus.
As already mentioned, rubella is a great danger to pregnant women. Very often, intrauterine infection of the fetus occurs. This leads to severe heart defects, microcephaly and congenital mental retardation in the unborn child.
Immunoglobulins
After the rubella virus enters the body, the immune system produces antibodies (immunoglobulins). They are divided into 2 classes - G and M.
Rubella class G antibodies (Anti-Rubella-IgG) begin to develop 21 to 28 days after the onset of the disease, when the acute manifestations of the pathology have already disappeared. Immunoglobulins of this group remain in the body of an ill person throughout life, thanks to them, a stable natural immunity to the virus is formed.
Immunoglobulins M begin to be produced on the first day of the disease. Their maximum production is observed on 14-21 days. 6 to 8 weeks after the onset of the disease, their formation stops. Only antibodies of group G remain in the blood.
A special blood test helps to detect the presence of antibodies. The concentration of immunoglobulins G is determined in the biomaterial . What does the positive Anti-Rubella-IgG mean in the transcript of the analysis? This result indicates that the level of immunoglobulins is sufficient for the formation of stable immunity.
Indications for analysis
A blood test for Anti-Rubella-IgG is prescribed to detect immunity to the rubella pathogen. It is shown in the following cases:
- during pregnancy;
- before rubella vaccine;
- when planning a pregnancy.
This analysis allows you to determine the indications for vaccination.
Training
In order for the analysis data to be reliable, it is necessary to carefully prepare for the study. Before the test, the following rules must be observed:
- Before taking blood, you must refrain from eating for 8 hours.
- Two to three days before the analysis, you need to stop drinking alcohol and fatty foods.
- 1 hour before the blood sampling should stop smoking.
It is not recommended to donate blood for antibodies to rubella immediately after fluorography, x-ray, ultrasound examination and physiotherapy.
How to do a test
Blood is taken from a vein for examination. The biomaterial is sent to the laboratory and examined by serological or enzyme immunoassay.
The serological method today is used less and less. It quite often gives false results. In addition, with this method of studying biomaterial, it is rather difficult to determine the class of antibodies.
Therefore, at present, the enzyme immunoassay is most often used. It gives reliable results in 97 - 98%.
Decryption
In the transcript of the analysis, the following concentration of class G antibodies to Rubella virus may be indicated:
- Less than 5 IU / ml. This result is considered negative. The level of antibodies is insufficient for the presence of immunity.
- From 5 to 9.9 IU. This is a dubious test result. It is also called the "gray zone". It is recommended to retake the analysis.
- From 10 IU / ml or more. In this case, doctors are talking about the positive Anti-Rubella-IgG. What does it mean? Such data indicate a sufficiently high concentration of antibodies. A person has already formed an immunity to the rubella pathogen.
Very often, when conducting this test in the blood, not only class G antibodies are determined, but also class M immunoglobulins. Identification of their level is very important for the correct interpretation of the analysis results. Consider this data in more detail:
- IgG and IGM are negative. The patient had never previously had rubella and was not vaccinated.
- Negative IgM and positive Anti-Rubella-IgG. What does it mean? This result suggests that a person has had rubella in the past, but is currently healthy. He has immunity against the virus. Such results are also observed in patients who have been vaccinated.
- Positive IgM and negative IgG. Such results indicate that a person has rubella.
- Positive Anti-Rubella-IgG and IgM. If both classes of antibodies are present in the blood, then this indicates that a person has recently had rubella. This result is usually observed 3 to 8 weeks after the first signs of the disease.
Need for vaccination
If positive Anti-Rubella-IgG is detected during pregnancy planning, the patient does not need vaccination. She already has immunity against rubella. However, it is important to pay attention to the indicators of immunoglobulins M. If these antibodies are present in the blood, then this indicates the presence of the disease. In this case, a course of treatment against rubella should be taken.
If during pregnancy planning the analysis did not reveal the presence of antibodies G and M, then this indicates the absence of immunity. In this case, the woman is recommended to be vaccinated against rubella. Conception is allowed no earlier than 3 months after vaccination.
Positive Anti-Rubella-IgG during pregnancy indicates that a woman has had rubella in the past or has been vaccinated. She can not be afraid of infection. However, if at the same time, class M antibodies are present in the analysis, then this indicates that the patient is sick with rubella. She needs to undergo treatment. Since this disease is extremely dangerous for the fetus, doctors often recommend terminating the pregnancy.
If the pregnant woman does not have antibodies to Rubella, then this indicates that her body is defenseless against the rubella virus. It is strictly contraindicated to vaccinate during the period of gestation. In this case, great care must be taken and contact with rubella patients should be avoided.
There are times when a person has never been diagnosed with rubella, but a positive Anti-Rubella-IgG is detected in the blood. What does it mean? Most likely, the patient suffered rubella in an erased form, and the disease was not detected in him. Also, a person may not remember that he was vaccinated against rubella in early childhood. In any case, such an analysis result clearly indicates the presence of persistent immunity.