Lecture of Measles (Rubeola)

2021-03-23 12:00 AM

When there is measles, the virus stimulates the body to produce antibodies. Antibodies appear 2-3 days after the onset of the rash and persist for a long time. Immunity in measles is stable immunity.

Define

Measles is an acute infectious disease caused by the respiratory tract, caused by the measles virus. The disease is clinically characterized by fever, respiratory tract inflammation, gastrointestinal tract, eye conjunctivitis, and ordered rash. The disease mainly occurs in children and easily develops epidemics.

Research history

Measles has been recorded since 2000 years ago.

Year 910 Rhazes - Persian Gulf doctor - describes the clinical picture of measles.

 1846 Peter Panum - Danish Doctor - clinical, epidemiological, measles study on Faroe Island.

 In 1950 Enders and Peebles successfully cultured the measles virus on human kidney and monkey kidney cells discovered the cytotoxic mechanism and opened the direction of measles vaccine production.

In 1960 the measles vaccine was administered in Burkina Faso, Upper Volta, Central Asia, and West Asia.

 1977 With a worldwide open vaccination program, measles was controlled.

In 1990 the measles incidence decreased by 90%, the measles death rate decreased by 95%.

Epidemiology

Pathogens

Measles virus belongs to the family Paramyxoviridae, spherical virus, 120-250 nm in diameter, the lipid is surrounded by a layer of Glycoprotein. The genome is a single strand of RNA with a molecular weight of 4.6 x 10 6 D, containing 16,000 nucleotides.

The measles virus has 2 main antigens:

Red blood cell agglutination antigen (Hemagglutinin).

Hemolysin-soluble antigen (Hemolysin).

When there is measles, the virus stimulates the body to produce antibodies. Antibodies appear 2-3 days after the onset of the rash and persist for a long time. Immunity in measles is stable immunity. By combining complement and red blood cell agglutination techniques ... help diagnose the disease.

The measles virus has a weak tolerance, easy to kill with common disinfectants, sunlight, heat, etc. at 56 °C, the virus is killed in 30 minutes.

Inoculum

Be a patient. The disease can be spread from 2 to 4 days before the rash develops until 5-6 days after the rash develops.

Infection

Inhalation: When the patient coughs, sneezes, talks, etc. Indirect transmission through contact is rare because the measles virus is easily eliminated in the outside world

Pathogenicity and immunity

The rate of infection is 100% in people who are not immune. Strong transmission in groups that do not have immunity (kindergartens, kindergartens ...)

Common in children from 1-4 years old. Children under 6 months of age are less susceptible to maternal immunity.

Adults are less likely to get sick. If infected, usually people in highland, remote, remote islands, etc. from childhood not exposed to measles virus.

The disease usually spreads in the winter-spring.

Immunity after recovery is stable, so it is very rare to get infected a second time.

As immunodeficiency disease, patients are susceptible to other diseases.

Mortality is high: 0.02% in advanced countries, 0.3-0.7% in developing countries.

Currently, thanks to the "Expanded Immunization Program" in our country, the morbidity and mortality rate has been greatly reduced.

Mechanism of pathogenesis and pathology

Mechanism of pathogenesis

The measles virus enters the body through the respiratory tract. The virus multiplies in the epithelial cells of the respiratory tract and in neighbouring lymph nodes. Then, into the blood (first viral infection). This period corresponds to the incubation period.

From the blood, according to the leukocytes, the virus to the target organs (lungs, spleen, lymph nodes, skin, eye conjunctiva ...) causes damage to these organs and causes clinical symptoms in the full-blown period. . Rashes on the skin and mucous membranes are the elimination of viruses and pathological immune responses of the body.

From about 2-3 days from the time the rash develops, the body produces antibodies. Antibodies neutralize the virus. The disease moves to a period of recovery.

Pathological anatomy

The typical pathological lesion is the appearance of giant cells (Hecht cells). These cells are found in the lymphoid, epithelial mucosa, pharynx, lungs, gastrointestinal tract, and so on. . These are cytoplasmic cells with extensive cytoplasm with many nuclei (50 to 100 nuclei) and seeds buried in the nucleus and protoplasm. Giant cells appear 4 - 5 days before the eruption and last 3 - 4 days after the eruption

clinical

Divide the clinical form

Divide the disease according to prognosis

Light form.

Moderate (Typical Conventional).

Severe form (Malignant measles).

Divide the disease according to age, terrain

Measles in infants, malnourished rickets, vaccinated people, pregnant women, measles in patients combined with other infectious diseases.

Symptoms study according to each clinical form

Medium form (typical conventional form)

Incubation: 8-11 days.

Onset (period of exudative inflammation): 3-4 days.

Sudden onset of mild or moderate fever, following high fever.

Nasal secretory inflammation, throat, eyes: Nasal discharge, cough, conjunctivitis, rusty eyes, swelling of eyelids.

The internal rash appears (day 2): Called Koplik seeds, which are white, pin-like particles, from a few nodules to several tens, several hundred nodules growing on the cheek lining (inside the mouth, across the molars) , around the Koplik seed cheek mucosa is often congested. Koplik particles only last 24-48 hours. This is a sign of value for an early and sure diagnosis.

Swollen lymph nodes.

Blood tests at this stage have no signs of leukocytes may increase moderately, Neutrofil may increase.

Full rash (eruption stage):

The rash grows on 4th - 6th day of the disease. The rash form is a maculopapular rash with a small, raised, raised rash on the skin's surface, alternating with a pink maculopapular rash. The rash grows scattered or attached to each other in circles of 3-6 mm, between the rash is the healing skin. The rash grows in the following order:

Day 1: Grows behind the ears, spreads to the face.

Day 2: Spread down to chest, arm.

Day 3: Spread to the back, legs.

Ban lasts 6 days and then flies in the same order as it grows.

The rash grows inside the mucosa (internal rash): The rash grows in the gastrointestinal tract, causing digestive disorders, loose; in the lungs cause bronchitis, cough.

Body as a whole: When it starts to grow, the whole body gets worse, has a higher fever, and gets more tired. When the rash grows to the legs, the temperature gradually decreases, the symptoms of the whole body subside and then go away.

Testing at this stage has decreased leukocytes, decreased neutro, and relatively increased lymphocytes

Correction (rash stage):

Usually on the 6th - 7th day the flight begins. The rash flies in the same order as it has grown, leaving behind thin, fine exfoliating bruises, chalk dust or bran dust. The dark spots of the rash and the normal skin that creates patchy skin colour are called a "tiger stripe" sign that is specific for diagnosis. The whole patient's body recovers gradually if no superinfection or complications.

Light form

No fever or mild fever.

Mild inflammation of nasopharyngeal secretions.

Ban sparse, fuzzy, fast diving.

Common in children under 6 months (still immune of the mother), in those who have been vaccinated.

Note: Measles prognosis assessment must be based mainly on the systemic toxic infection syndrome, should not only rely on the rash, because the rash can be mild but can also be in severe form when the child fails nutrition, immunodeficiency. Conversely, thick eruption is not necessarily severe because it can be found in well-nourished children with a good immune response

Severe form (malignant measles form)

Malignant signs usually appear rapidly after a few hours, at the end of the onset period, before the rash develops on hypersensitive sites. Usually have the following symptoms: High fever 39 - 41 0 C, gloomy, struggling, delirium, lethargy, convulsions, tachycardia, blood pressure drop, rapid breathing, cyanosis, vomiting, diarrhoea, urination little, bleeding under the skin or viscera ... Depending on which symptoms stand out, there will be:

Hemorrhagic measles: Hemorrhage under the skin or internal organs.

Bronchopulmonary malignant measles: The main manifestation is respiratory failure.

Malignant measles severe poisoning: High fever, struggles, strong convulsions, coma, small tachycardia, drop in blood pressure.

Malignant measles with diarrhoea: Outstanding digestive disorder.

Acute abdominal malignant measles: Like appendicitis common in children from 6 months to 2 years old, children with malnutrition or rickets, immunodeficiency, children with other diseases ...

The disease form according to age, geography

Measles in babies under 6 months is usually mild.

Measles in children 6 months - 2 years: Usually severe.

Measles in malnourished children - rickets: Measles is usually atypical and severe.

Measles in children immunocompromised with Gamma globulin or vaccine: Usually mild.

Measles in pregnant women: Causes miscarriage, deformity, premature birth ...

Measles causes immunodeficiency, so when combined with other infections such as whooping cough, tuberculosis, diphtheria ... worsen the disease.

Implementing the quadrants

Clinical basis

Severe toxic infection syndrome.

Early-stage board: Koplik seed.

Inflammatory respiratory syndrome.

Swelling of eyelids, eye conjunctivitis.

Gastrointestinal disturbances, diarrhoea.

Full-development stage: Maculopapular papules grow from face to body and limbs. The flight board is also in the same order and leaves a "tiger skin mark" on the skin.

Test basis

Isolation of the virus from blood, nose and throat (early stage). Practically very little applies.

Find Hecht giant cells in nasopharyngeal secretions (less applicable).

Serum diagnosis: Red blood cell agglutination reaction, complement combination reaction, ELISA reaction. These tests should be done on days 3-4 when there is a suspicion of measles, done 2 times, 7-10 days apart, the antibody titer for the second time increases 4 times to be valid.

The above tests have little practical value because they are difficult to perform.

Epidemiological basis, age, season

Differential diagnosis

Rubella (or German measles)

Mild fever, mild respiratory inflammation, unknown signs of infection and intoxication.

The measles maculopapular rash is usually smaller, grows sparsely and grows early from day 1-2, grows at the same time, leaving no bruises when flying, without Koplick seeds.

Nodules behind the ears, painful swelling.

Blood test: Plasmocyte.

Diagnosis is confirmed by erythrocytic cell agglutination reaction.

Viral disease with other rashes (Adeno Virus, ECHO, Coxsackie etc.)

A measles-type maculopapular rash usually grows out of order.

Allergy board

Macular (urticaria) rash on the whole body out of order, often itchy, with medication, weather, food, etc.

Symptoms

Respiratory complications

Laryngitis

Early-stage is caused by the measles virus: Appears in the onset stage, the early stage of rash usually disappears with the rash, or has a fake Croup, causing shortness of breath due to laryngospasm.

Late-stage: Due to superinfection (often due to staphylococci, streptococci, pneumococci ...), appearing after the eruption. Usually severe: High fever, coughing, hoarseness, difficulty breathing, cyanosis.

Bronchitis

Usually due to superinfection, which occurs at the end of the eruption period. Expression of fever again, cough a lot, listening to the lungs with bronchial ran, increased white blood cells, increased neutro, radiographs bronchitis images.

Bronchopneumonia

Due to superinfection, usually appears late after rash. Severe manifestations: High fever, shortness of breath, lung examination with bronchial ran and exploding. X-ray image of bronchitis inflammation (blurred nodules scattered about 2 lungs). Increased leukocytes, increased neutrons are often the cause of death in measles, especially in young children.

Neurological complications

Encephalitis - meningitis - acute marrow caused by measles virus

Encephalitis: is a dangerous complication causing death and high sequelae. Meet in 0.1-0.6% of measles patients. Common in older children (school age), in the first week of the committee (3-6 days of the committee). Sudden onset, febrile convulsions, consciousness disorders: gloom - coma, paralysis of 1/2 person or 1 limb, paralysis III, VII, or pyramidal syndrome - extrapyramidal, cerebellum, pre- family etc.

Serum meningitis (caused by the measles virus).

Myelitis: Paralysis of the lower extremities, sphincter disorder.

Mechanism: There are 2 hypotheses, namely an allergic reaction or a pathological immune response.                                                                                                                                           

Meningitis due to superinfection

Meningitis after ear infections, sinusitis, pharyngitis ... due to superinfection.

Fibrotic subacute white matter encephalitis (Van Bogaert)

Often seen at the age of 2-20 years old, appearing late sometimes after a few years, this means that the measles virus can potentially live for many years in the patient's body, in patients with abnormal immune responses. Semi-level movements from a few months to a year. The patient died in a state of increased muscle tone and cerebral spasticity.

Gastrointestinal complications

Inflammation of the oral mucosa

The measles virus is initially caused, usually goes away with the rash.

Later later often due to superinfection.

Black pipe orange (noma)

Late appearance, due to superinfection Vincent spirochetes (Leptospira vincenti) is a type of spirochete gangrene, causing ulcers of the oral mucosa, spreading deeply into the jaw bone causing mucosal necrosis, osteomyelitis, tooth loss, bad breath .

Enteritis

Due to superinfection of bacteria such as Shigella, E. coli ...

Complications of the ear - nose - throat

Ear infections - mastoid ear infections.

Superinfection nasopharyngitis.

Complications due to immunodeficiency

More susceptible to other diseases such as tuberculosis, diphtheria, whooping cough etc.

Treatment

The principles of treatment

Mainly symptomatic treatment-care and nurturing.

Antipyretic: Physical methods, common antipyretic drugs (paracetamol).

Sedative.

Cough medicine, expectorant.

Antihistamines: Dimedron, pipolphen.

Nasopharyngeal antiseptic: Small eye drops with a solution of chloromycetin, Argyrol.

Use vitamin A for children with measles as recommended by WHO:

Children aged 0-5 months use 50,000 UI / day x 2 days, then take 2 weeks off and add 50,000 UI / day x 01 more day.

Children from 6-11 months old use 100,000 UI / day x 2 days, then take 2 weeks off and use another 100,000 UI / day x 01 day.

Children from 12 months old and older use 200,000UI / day x 2 days, then take 2 weeks off and use an additional 200,000 UI / day x 01 more days.

Ribavirin and other immunostimulating agents are also recommended in the treatment of measles, but due to their high cost, they are rarely used in developing countries.

Antibiotics are only used in case of superinfection and for children under 2 years old, and malnourished children.

In case of complications: Laryngitis, encephalitis, malignant measles, antibiotics and corticosteroids are used.

Resuscitation measures depending on the patient's symptoms: Respiratory resuscitation in case of respiratory failure (O2 breathing, respiration, etc.) cardiovascular resuscitation, etc.

The diet is liquid, soft, full of nutrients, vitamins and minerals

Prevention

Gamma globulin 0.25 mg/kg is used for emergency prophylaxis for malnourished children, or children suffering from another disease that has been exposed to measles.

Measles vaccine: A live, attenuated vaccine used for children 6 - 9 months old and older, has a high protective effect. The measles vaccine is a compulsory vaccine in the "expanded immunization program" in our country today. As a result, the current morbidity and mortality rate of measles has been greatly reduced.