Measles

Measles

Measles is one of the most important causes of childhood mortality in developing countries.

There is only one serotype.

It can be eradicated from the globe as the vaccine is known to be effective.

It causes only acute infection except in patients with SSPE.

Human is the only reservoir.

Transmission

Transmission is through respiratory route.

Incubation period- 8 to 13 days.

Infectious period starts from 1 day before the onset of fever until 4 days after the development of rash.

Clinical presentations

The clinical illness begin with the feeling generally unwell

Young children may refuse to eat.

Most children will then develop fever and conjunctivitis.

Koplik’s spots ( which resemble salts) develop in the buccal mucosa. This spots are pathognomic signs of Measles.

Skin rashes are characteristically maculopapular, but in some immunocompromised patients and in some patient who has partial immunity, the rashes could be atypical. Others may even not develop rashes at all.

Complications of measles

Ø Pneumonitis

Ø Encephalitis

Ø Subacute slerosing panencephalitis (SSPE)

Ø Malnutrition

Ø Missed abortion (Measles is not associated with congenital abnormality)

Investigation

Investigation

Diagnostic tests

Serum (clotted blood) for Measles IgM

The virus can be isolated from nasopharyngeal aspirate, saliva or urine. The viral RNA may be detected on these specimens.

Measles antibody

Measles IgM Measles IgG

Acute/ recent infection + +

Past infection/ immunisation _ +

Screening tests

Serum (clotted blood) for Measles IgG.

Health care workers and travellers to endemic countries should be screened and if they are found to be susceptible, they should be given vaccination.

After exposure, pregnant women and immunocompromised patients should be tested for immunity if they do not have history of vaccination or past infection.

Treatment

There is no effective antiviral therapy.

Respiratory isolation is important to contain transmission.

Immunocompromised patients with measles may be treated with Ribavirin even if there is no evidence for its efficacy in vivo.

Secondary bacterial infections should be treated with appropriate antibiotics.

Prevention

The live vaccine is effective to prevent infection.

Vaccination is recommended to all susceptible individual over the age of 9 months.

Susceptible pregnant women, immunocompromised persons and children under the age of 6 months may be given human normal immunoglobulin after exposure.

Post-exposure prophylaxis with the vaccine is recommended to other susceptible individuals.