Rubella – an acute viral disease characterized by fever and moderately expressed intoxication, lymphadenopathy, rashes and high risk of affecting fetal at development in pregnant women.
Pathogen by its main properties similar to the family Togaviridae. It is an RNA virus, that dies quickly upon drying, heating, under the influence of UV radiation and disinfectants.
Epidemiology. The source of infection are patients with various forms of rubella – acquired and congenital. Children with congenital rubella remain contagious from a few months up to 1.5 years.
The virus is released into the environment from a patient with human droplets of nasopharyngeal mucus, the main route of transmission – airborne. In addition, the infection is transmitted vertically from mother to fetus.
The susceptibility to the disease is high, with the exception of children of the first year of life, having a passive immunity transmitted from the mother. The seasonal rise in incidence observed in March-June. People have been ill rubella have a strong immunity.
Pathogenesis. Rubella virus enters the human body through the mucous membranes of the respiratory tract, then into the blood and hematogenically – in various organs and tissues. In severe forms of the disease affects the central nervous system that leads to the development of meningitis, encephalitis.
Rubella virus, crosses the placenta, damaging the fetus, and the frequency and nature of the damage depends on the time of pregnancy in which the infection was in a woman. Infection in the first 2 months of pregnancy leads to multiple malformations in 40-60% of cases, at a later date – at 30-50%, and malformations are rare.
Rubella can be acquired and congenital.
Acquired rubella occurs cyclically like an acute infectious disease. The incubation period is 11-24 days. In some patients, the first sign of rubella is a petty pink color rash, and fever, intoxication absent. In some patients the disease begins with malaise, headache, pains in the joints, muscles, transient increase in body temperature. The rash appears on the 1-3 th day of illness and spreads throughout the body.
Rash elements almost never coalesce, much paler keep for about 3 days and disappear without pigmentation, and peeling. A characteristic feature of rubella – lymphadenopathy, when increased nuchal lymph nodes. In 25-30% of people rubella occurs without a rash and is accompanied by a lymphadenopathy, slight fever and intoxication.
Among the complications rubella: migratory arthritis (mostly in women), ear infections, pneumonia, thrombocytopenia, manifested with hemorrhagic rash. Rare, but extremely severe complications is the encephalitis and encephalomyelitis. They are more common in adults. There are increasing headache, nausea, vomiting, seizures, impaired consciousness, sometimes paresis and paralysis. Mortality in encephalitis and encephalomyelitis in adults up to 20-50%.
The symptom of congenital rubella depends on the duration of infection of the fetus. When infection of the fetus in the early stages of development, when there is a development of various organs and systems, damaged organs of hearing, vision, skull, limbs. The most commonly in infants discover – microphthalmia, cataract, glaucoma, deafness and heart defects. If fetal infection occurs in the last stages of pregnancy, the in the neonate is observed an enlarged liver and spleen, haemorrhagic syndrome, the symptoms of hepatitis, pneumonia.
Diagnostics. The similarity of rubella with the measles, scarlet fever, an allergic rash, and a number of other diseases, which are the main symptoms of fever and rash, causes difficulties for clinical diagnosis.
Therefore, it is desirable to verify rubella using HAI. For the study the first sample of blood taken in the first 3 days of the rash appears, the second – in 7-14 days, the growth is considered positive if antibody titer 4 times or more. Currently, diagnosis using ELISA and RIA. During the verification of congenital rubella infection in the newborn use a kits for TORCH-infections.
Rubella patients are hospitalized only on clinical and epidemiological indications and basically treat at home. A promising area the prevention of rubella is vaccination.