MEASLES

RUBEOLA OR MORBILLI

DEFINITION• Measles is an acute highly contagious viral

disease caused by measles virus.It is characterized by fever,URT catarrhal inflamation, koplik’s spots and ulemaculopaps.

• The disease may complicated with branch- pneumonia, encephalitis, hepatitis.

• The lived attenuated measles virus vaccine has been utilized wildly since 1965 ,the incidence of the disease has declined in china.

ETIOLOGY• 1 .Pathogen is measles virus.

it has been classed as a paramyxovirus.it is spherical in appearance ,measuring about 100~150nm in diameter.It has an outer envelope composed of M-protein, H-protein, F-protein, and internal core is RNA.

• 2 .Site of the measles virus exists

measles can be detected from blood and nasal, pharyngeal secretions.

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• 3. Three kinds of antibodies are produced after infection,that is

• 3.1 complement combining antibody;

• 3.2 hemagglutinin inhibiting antibody

• 3.3 neutralizing antibody

• 4 .Only one antigenic type of measles virus

• is known.

• 5.Resistance:measles virus is sensitive to

heat or disinfectant , it is also inactivated by ultraviolet light easily. not strong

EPIDEMIOLOGY• 1.Source of infection The patients are the only source of infection. • 2 .Routes of transmission air-borne• 3. Susceptibility of population 3.1 All age person is susceptible; 90% of

contact people acquire the disease. 3.2 The permanent immunity acquire after

disease.• 4. Epidemic features season:winter and spiring age:6 months to 5 years old

PATHOLOGY

• Rash: corium superficial blood vessel• Pigmentation:• Desquamation:• Koplik’s spots

CLINICAL MANIFESTATIONS• Typical type

• 1.Incubation period is approximately 6~18days,10days is the most common.

(3-4weeks)• 2 .predromal phase 3~4 days. 2 .1 Fever; 2 .2 Catarrhal inflammation of URT; 2 .3 Koplik’s spots; 2 .4 Transient prodromal rashes.

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• 3. Eruption stage 3 .1. Time: the3~5 days after fever;but the 4th

day is most common; 3 .2 . Shape:maculopapular 3.3. Sequence:behind the ear→along the

hairline→face→neck→chest→back→abdomen→limbs→hand and fee.

3 .4 . The temperature rise continuously and companied with the toxic symptoms

• 4 . Convalescent stage brown staining. fine branny desquamation. course:10-14 days

• Atypical measles

1 . mild measles;

2 . severe measles (toxic and shock type measles);

3. hemorrhagic measles;

4 . variant measles.

COMPLICATIONS• 1 .Bronchopneumonia;• 2 .Myocarditis;• 3 .Laryngitis;• 4 .Neurologic complications: Encephalitis

LABORATORY FINDINGS• Blood routine• Serum Ab measurement

complement combining antibody;

hemagglutinin inhibiting antibody;

neutralizing antibody;

specific antibody IgM.• Other Ag and multinucleated giant cells

Diagnosis:Diagnosis:•Diagnosis is usually clinical.•Multinucleated giant cells are detected in nasopharynx mucosa secretions.•Virus isolation: •Resp secretion•Buffy coat•urine

•RT-PCR•Serology: commonly used technique. Specific IgM

DIFFERENTIAL DIAGNOSIS

• 1 .Rubella (German measles) ;• 2 .Roseola infantum (infant

subitum,exanthem subitum)• 3. Drug rashes.*the early stage definite diagnosis is:*the early stage clinical diagnosis is: *the clinical diagnosis is:

treatment

• 1 .General therapy: rest, nursing and diet

• 2. Symptomatic therapy: fever and cough,

• 3.Support threapy:r-globulin traditional chinese herbs may be

used ;• 4.complications of treatment

PREVENTION• 1 .Control source of infection;• 2 .Interruption of transmissions ;• 3 .Protection of the susceptible person: 3.1 . Active immunization Lived attenuated measles vaccine.3.2 . Passive immunization placenta globulin or gamma globulin.