Rubella

Introduction to rubella Rubella (Germanmeasles) is a common acute infectious disease caused by rubella virus. It is characterized by fever and systemic rash. It is often accompanied by swelling of the ear and occipital lymph nodes. The systemic symptoms are generally mild and the course of disease is short. It is often thought that this disease is irrelevant, but in recent years, severe cases of rubella outbreaks have been reported frequently. If a pregnant woman is infected with rubella, it will seriously damage the fetus, and the child can become ill. Traditional Chinese medicine claims that the disease is rubella, wind sputum, and rash. It is thought to be caused by wind and heat. basic knowledge The proportion of illness: 0.23% Susceptible people: no special people Mode of infection: contact spread Complications: gastrointestinal bleeding, blood in the stool, nephrotic syndrome, acute herpes simplex encephalitis, arthritis, otitis media

Rubella cause

(1) Causes of the disease

The rubella virus is an RNA virus, belonging to the family Togaviridae. It is a virus confined to humans. It is spherical in shape under electron microscope, with a diameter of 50-70 nm, a core of 30 nm, a coating thickness of 8 nm, and a lot of surface 5 ~6nm outwardly protruding structure containing hemagglutinin, the virus particles are composed of RNA and a shell (capsid) protein (C) and three envelope proteins (E1, E2a and E2b), E1 and E2 have good The immunogenicity can cause the body to produce neutralizing antibodies and hemagglutination inhibitory antibodies. The rubella virus is only one serotype, and there is no antigen crossover with more than 60 viruses of the togaviridae. The rubella virus can be in the placenta or the fetus (and born) Survival in the next few months or even years, causing long-term, multi-system chronic progressive infection, the virus can grow in rabbit kidney, milk field rat kidney, green monkey kidney, rabbit cornea and other cell culture, can agglutinate chicken, pigeon, goose And human "O" type red blood cells, the virus has weak viability in vitro, sensitive to ultraviolet light, ether, chloroform, formaldehyde, cesium chloride, sodium deoxycholate, etc., pH<6.8 and >8.1 are not easy to grow, pH< 3.0 can inactivate it, the virus is not heat resistant, 56 ° C 30 min, 37 1.5h may be killed, 4 stored unstable at -60 ~ -70 remains active for three months, 9 months can be stored under dry ice.

(two) pathogenesis

After the patient is infected with rubella, the rubella virus first replicates in the upper respiratory tract mucosa and cervical lymph nodes, and then enters the blood circulation to cause viremia. It spreads to the lymphatic tissue of the whole body and causes lymphadenopathy. The virus directly damages the vascular endothelial cells and causes rash. It is caused by the antigen-antibody complex caused by rubella virus caused by capillary inflammation of the upper dermis. The disease is mild, the pathological findings are not many, the skin and lymph nodes are acute, chronic non-specific inflammation, and the rubella virus can cause encephalitis. Brain tissue edema, non-specific perivascular infiltration, neuronal degeneration and mild meningeal response, can also cause chronic whole encephalitis due to chronic persistent lesions after infection for more than ten years. The pathogenesis of congenital rubella is still not clear. It is known that after pregnant women are infected with rubella, rubella virus can infect the fetus at the viremia stage with bloodstream infection, and the placental chorion is infected with a long-lasting small blood vessel and capillary wall. The mother is at gestational age. Early infection with rubella, the more chance the fetus is infected, the first month of gestational age 10% to 50% are infected, 10% to 30% in the second month, 5% to 20% in the third month, and 1% to 5% in the fourth month. There may still be a small number of fetuses infected in the future. Due to the fact that the fetus, especially the fetus infected by rubella virus, lacks cellular immune function and does not produce interferon, the rubella virus is widely present in the body for a long time, and it will invade the next generation of cells when it is divided with the fetal cells, and proliferate and pass through. Sustained, multiple organ systemic infections, and resulting in a variety of congenital defects, it is called congenital rubella syndrome, the most common are cataract, neurological deafness, congenital heart disease, meningoencephalitis, myocardial necrosis, Interstitial pneumonia, giant cell hepatitis, nephritis, hypospadias, etc., such newborns continue to detoxification for several months or even years after birth, there are many no obvious symptoms after birth, but serological tests have proved that the fetus has been Rubella virus infection, in recent years, has repeatedly revealed that children with congenital rubella often have progressive abnormal immune response.

Rubella prevention

Because the symptoms of this disease are light, the general prognosis is good, so it does not need special prevention, but congenital rubella is harmful, can cause stillbirth, premature delivery or a variety of congenital malformations, so prevention should focus on congenital rubella.

Autoimmune International has been widely used for more than ten years in the application of rubella attenuated vaccines, which have proved to be safe and effective. The antibody positive conversion rate after vaccination is above 95%. After vaccination, only some have short-term fever, rash, swollen lymph nodes and joint swelling and pain. After the reaction, most of the antibody persistence can be maintained for more than 7 years after immunization. Different countries are not uniform in terms of vaccination. For example, the United States advocates adolescents from 1 year old to adolescent, especially children in kindergartens and primary schools, as the main immune target, because children The incidence of rubella is the highest, and can be transmitted to pregnant women and other adults. Adolescent and adult women should also be vaccinated. Congenital rubella has been significantly reduced. Although the current impact of the rubella vaccine strain on the human body and the fetus is not enough, the live vaccine is weak. The virus can indeed cause fetal malformation through the placenta infection, so pregnant women should not accept such live vaccines. Rubella has already been used in combination with measles and mumps vaccines, and has achieved good results. At present, China has also made live attenuated rubella vaccines. The place has begun to be used and will be gradually incorporated into the planned immunization implementation, focusing on the immune object package Unmarried women of childbearing age, including high school, junior high school graduating class girls.

The effect of immunoglobulin on the prevention of rubella is still uncertain.

Rubella complications Complications, gastrointestinal bleeding, hemorrhagic nephrotic syndrome, acute herpes simplex virus encephalitis, arthritis, otitis media

Rubella is generally mild and has few complications. Only a small number of patients may have otitis media, pharyngitis, bronchitis, pneumonia or myocarditis, pancreatitis, hepatitis, gastrointestinal bleeding, thrombocytopenic purpura, hemolytic anemia, nephrotic syndrome, acute and chronic Nephritis, etc., the heavier ones have the following:

(1) Encephalitis is rare, the incidence rate is 1:6000, mainly found in children, generally occurs 1 to 7 days after rash, headache, lethargy, vomiting, diplopia, neck stiffness, coma, convulsions, ataxia , limb paralysis, etc., cerebrospinal fluid changes similar to other viral encephalitis, the course of disease is relatively short, most patients self-healing after 3 to 7 days, a small number of residual sequelae, but also chronic progressive whole encephalitis, Shanghai Medical University Pediatric Hospital 86% of children with rubella who were hospitalized at the peak of the rubella epidemic in 1993 had encephalitis, and 7 had severe coma. Although the course of disease was longer, they were cured after treatment.

(B) patients with myocarditis complained of chest tightness, palpitations, dizziness, weakness, electrocardiogram and cardiac zymogram changes, more than 1 or 2 weeks of recovery, and other complications such as encephalitis.

(3) Arthritis is mainly seen in adults, especially women, and there are reports of children with rubella arthritis in China. The principle of occurrence is not completely clear. Multi-line viruses directly invade the joint cavity or immune response, and the knuckles during the rash Red, swollen, painful, wrist and knee joints contain mononuclear cells, sometimes several joints are swollen and painful, similar to rheumatoid polyarthritis, but most of them can disappear within 2 to 30 days.

(D) bleeding tendency is rare, due to thrombocytopenia and increased capillary permeability, often after the rash suddenly bleeding, skin and mucous membrane spots, ecchymosis, hematemesis, blood in the stool, hematuria, mostly within 1 to 2 weeks Self-remission, a small number of patients with intracranial hemorrhage can cause death.

(5) Others may have liver and kidney dysfunction.

Rubella symptoms common symptoms hypothermia sore throat spotted lymphadenopathy

1. Acquired rubella (or naturally infected rubella)

The incubation period averages 18 days (14 to 21 days).

(1) prodromal period: shorter, about 1 to 2 days, mild symptoms, low or moderate fever, headache, loss of appetite, fatigue, fatigue, cough, sneezing, runny nose, sore throat, combined with membrane congestion Upper respiratory tract inflammation, occasional vomiting, diarrhea, nosebleeds, swelling of the gums, etc. Some patients have rosy or hemorrhagic rash in the soft palate and pharynx, but the buccal mucosa is smooth, no congestion and Coriolis spots, generally speaking, infants and young children Patients with prodromal symptoms are often mild, or have no prodromal symptoms, while older children and adults are more significant and can last 5 to 6 days.

(2) rash period: usually rash occurs 1 to 2 days after the onset of rash, rash first seen in the face and neck, spread down quickly, covered with trunk and limbs within 1 day, but palm, foot mostly rash-free, rash at the beginning It has a fine reddish spotted rash, maculopapular rash or papule, with a diameter of 2 to 3 mm. The face and distal rash of the extremities are sparse. Some of the fusions resemble measles. The trunk is especially dense with back rashes. It is fused into pieces and resembles scarlet fever.

The rash usually lasts for 3 days (1 to 4 days), and some people call it "three-day measles". The facial rash is characteristic of rubella. A small number of patients have hemorrhagic rash, and the body has a tendency to bleed. Low fever, mild upper respiratory tract inflammation, splenomegaly and superficial lymph nodes, especially in the back of the ear, occipital, posterior lymph nodes, the most obvious, swollen lymph nodes tender tenderness, no fusion, no suppuration, sometimes The spleen and lymphadenopathy of rubella patients can occur 4 to 10 days before the rash, the body temperature drops when the rash retreats, the upper respiratory tract symptoms subsides, and the swollen lymph nodes gradually recover, but it usually takes several weeks after the rash is completely recovered. After resolving, there is generally no pigmentation and no scaling. Only a few critically ill patients may have fine bran-like desquamation, and large peeling is rare.

No rash rubella: rubella patients can only have fever, upper respiratory tract inflammation, swollen lymph nodes, without rash, can also be infected with rubella virus without any symptoms, signs, serological tests for rubella antibodies are positive, so-called recessive infection Patients, in the epidemiological survey in different regions, found that the proportion of patients with dominant infection and no rash or recessive infection was 1:6 ~ 1:9.

2. Congenital Rubella Syndrome (CRS)

After the fetus is infected, the severe one can lead to stillbirth, miscarriage, premature birth, mild birth can cause fetal growth retardation, birth weight, length, head circumference, chest circumference, etc. are lower than normal newborns, this gap often cannot be corrected by 1 year old Such infants are prone to a variety of malformations. There are more than 5% of congenital malformations in neonates due to congenital rubella. Congenital malformations or diseases are common in cataracts, retinopathy, glaucoma, iridocyclitis, and neuropathy. Deafness, vestibular damage, otitis media, congenital heart disease, myocardial necrosis, hypertension, interstitial pneumonia, giant cell pneumonia, hepatosplenomegaly, lymphadenopathy, glomerular sclerosis, thrombocytopenic purpura, hemolytic anemia, regeneration Obstructive anemia, encephalitis, meningitis, microcephaly, mental retardation, etc. Rubella virus can be isolated from the pharynx, blood, urine and cerebrospinal fluid of children with congenital rubella. The positive rate is high within 1 year old. It is also reported that after congenital infection, rubella virus persists in brain tissue for 12 years. And cause progressive rubella encephalitis, most children with congenital rubella have temporary symptoms at birth, but also can develop progressive symptoms and new malformations within a few months to a few years after birth, malformations appear after 1 year old There may be deafness, abnormal mental movements, language barriers, skeletal deformities, etc., so for congenital rubella and possible children to be followed up to 2 to 3 years or 3 to 4 years after birth, foreign reports have been reported during a rubella pandemic 4005 newborns born by virus isolation or serum test proved congenital rubella >2% (only 0.1% of the local newborns are congenital rubella), 68% of the 4005 cases are subclinical, no during the neonatal period Symptoms or defects, but 71% of them were followed up in the first 5 years after birth, and various congenital rubella symptoms appeared in different periods. It can be seen that congenital rubella syndrome is a serious consequence of rubella virus infection. In recent years, the country has also been reported in 825 cases of women in early pregnancy, rubella IgM antibodies to detect positive rate accounted for 1.44% of its fetal blood rubella IgM positive rate of 62.5% of pregnant women infected.

Rubella check

(1) The total number of white blood cells in the surrounding blood is reduced, lymphocytes are increased, and atypical lymphocytes and plasma cells are present.

(2) Rapid diagnosis Recently, the direct immunofluorescence method was used to detect the rubella virus antigen in the exfoliated cells of the throat swab smear, and its diagnostic value needs further observation.

(3) Virus isolation General urticaria patients take nasopharyngeal secretions, congenital rubella patients take urine, cerebrospinal fluid, blood, bone marrow and other cultured cells such as RK-13, Vero or SIRC, can be isolated from rubella virus, and then immune Identification by fluorescence.

(4) Determination of serum antibodies such as erythrocyte agglutination test, neutralization test, complement binding test and immunofluorescence, double serum antibody titer increased more than 4 times positive, among which erythrocyte agglutination inhibition test is most commonly used, because it is fast and simple The reliable advantage is that this antibody appears at the time of rash, rises rapidly in 1 to 2 weeks, and falls to the initial level after 4 to 12 months, and can be maintained for life. Rubella-specific secretory IgA antibody can be found in the nasopharynx. It can help diagnose and also detect the rubella virus RNA by dot blotting to diagnose rubella infection.

Specific rubella antibody IgM is diagnostic. If congenital rubella is considered in the neonatal period, it is best to test both mother and infant specimens and make dynamic observations to determine whether the neonatal infection index is passively obtained from the mother. The rubella antibody gradually decreases with age. If the rash antibody is gradually increased during the follow-up, the baby has been infected. For this reason, it is best to observe several indicators.

Electrocardiogram and cardiac zymogram were changed in patients with complicated myocarditis.

Rubella diagnosis

diagnosis

The diagnosis of typical rubella patients is mainly based on epidemiological history and clinical manifestations, such as short prodromal period, upper respiratory tract inflammation, hypothermia, special maculopapular rash, post-ear, occipital lymph node swelling, etc., but during the epidemic, atypical patients and Patients with insidious infections are much more common than typical patients. For such patients, virus isolation or serum antibody determination must be performed to determine the diagnosis. The specific IgM antibody has diagnostic value. The IgM antibody disappears after 4 to 8 weeks of onset. Infants born with IgG antibodies and suspected of contracting rubella during pregnancy, regardless of symptoms or signs, should be isolated for rubella virus and IgM antibodies, positive for congenital rubella, specific for congenital rubella IgM antibody is different from natural infection. When the fetus is 16 weeks old, it has its own specific IgM. It continues to rise within 6 months after birth, and then gradually decreases, but it can be measured within one year, from the mother. The IgG antibody decreased several months after birth and the infant's own IgG rubella antibody continued to rise at the same time.

Rubella retinitis is often an important and even unique sign for the diagnosis of congenital rubella. There are often brown or dark brown spots or plaque-like pigment spots on the retina. In severe cases, the spotted phase is accompanied by a yellow lens. The retinal blood vessels are often narrower than normal.

Differential diagnosis

The rash form of rubella patients is between measles and scarlet fever. Therefore, we should focus on the differential diagnosis of these three common fever and rash diseases (Table 2). In addition, rubella needs to be associated with children's acute rash, drug rash, and infectiousness. Mononucleosis, enterovirus infection, such as coxsackievirus group A, 2, 4, 9, 16 and B, 1, 3, 5, Echo (ECHO) virus 4, 9, 16 Identification of infection, congenital rubella syndrome also needs to be differentiated from intrauterine infection with toxoplasmosis, cytomegalovirus infection, and herpes simplex virus infection. These three intra-fetal infections have similar symptoms to congenital rubella.

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