Measles: antibodies IgM and IgG to measles virus in the blood

Antibodies of IgM to measles virus in blood serum are normally absent.

The causative agent of measles ( morbilla ) is referred to the class of RNA viruses. Children of preschool age are more likely to get measles. However, those who are not infected with measles remain highly susceptible to it throughout their lives and can get sick at any age. For rapid diagnosis of measles, antigen detection is used in the cells of the nasopharyngeal or skin (from the elements of the rash) to be separated by the method of immunofluorescence microscopy (fluorine-labeled measles IgG is used in the reaction). An additional confirmation of the infection can be the detection of multinucleated cells in the nasopharyngeal discharge or smears-prints after stained by Romanovsky-Giemsa or Pavlovsky. Identification of antibodies to the measles pathogen is carried out in the inhibition of hemagglutination (RTGA), RSK, RPGA and ELISA.

Serological methods of investigation are used to confirm the diagnosis of measles, especially erased, atypical forms. The most commonly used are RTGA and RSK. Specific diagnosis is retrospective, since these reactions take into account the growth of antibody titer in paired sera. The first blood sample is taken no later than the 3rd day of the rash, the second - after 10-14 days. The diagnosis is considered verified only when the antibody titer increases 4 times or more. When applying the ELISA method, antibodies of IgM and IgG classes are detected.

IgM antibodies to measles are detected in the acute period of infection (within 6 days after the onset of the rash - in 80%, in 7 days - in 95% of patients), they peak at 2-3 weeks, hold for 4 weeks and then gradually disappear (50% of patients become seronegative after 4 months). IgG antibodies to measles appear in the period of convalescence, in those who have recovered they persist up to 10 years. Detection of IgG antibodies at the end of the acute period of the disease is a prognostically favorable symptom. Detection of IgM antibodies in the serum or an increase in the level of IgG antibodies in paired sera indicates more than 4 times the current infection. False positive results of IgM antibody determination can be obtained with chronic active hepatitis, systemic lupus erythematosus, infectious mononucleosis.

Determination of IgG antibody titer for measles is used for retrospective diagnosis of measles and evaluation of the intensity of measles immunity.

[1], [2], [3], [4], [5], [6],