» Measles - the underestimated danger

Measles is a worldwide spread infection triggered by the measles virus. Characteristic for measles is an influenza- style early stage and an exanthematous central stage. Due to its high infectiousness measles is mostly a children’s disease. They leave a lifelong immunity.

The disease is diagnosed through its symptoms, especially through its characteristic skin lesions. Measles is treated symptomatically. 10-20% of all people infected with measles in industrialised countries will suffer from complications due to the virus. These complications are of special importance because they are not only frequent but also increasingly lethal. Measles infection can be prevented by vaccination.

Under the infection protection law (in German only), which was introduced on 1 January 2001, measles fell under the category of infectious diseases that have to be registered obligatorily.

Frequency

Measles appear worldwide and mostly occur with toddlers and school children because of their high rate of infectiousness. While in Germany in the 1990s 50,000 infections were calculated, the number of registered infections has constantly dropped down to under 1,000, due to consequent vaccination of children. 0.1% of all infections lead to life threatening complications.

Worldwide more than 30 million people are being annually infected with measles. Even though vaccination has been possible for forty years, measles are still one of the most common reasons of death amongst small children. The WHO estimates 454,000 death cases due to measles in the year 2004, most of the victims being children.

Causes

Measles pathogen is the human pathogen RNS measles virus, which only infects humans. Infected and acutely ill people are the natural reservoir for the measles virus. The virus prefers cells of the immune and nerve system. At the same time, amongst others, giant cells develop, which are already detectable in the nose secretion at the pre-stage of the disease. Incubation period averages between eight and twelve days.

The measles virus is transmitted by droplet infection, e.g. by coughing, sneezing or speaking. The virus remains infectious for two hours in the air. Portal of entry are mucous membranes of respiratory organs and the conjunctiva of the eye. The risk of virulance is extremely high. Main risk of virulance is roughly five days before until four days after the appearance of the exanthema. 99 out of 100 infected people fall ill.

Babies of mothers who are immune (who either have had measles or have been vaccinated) are protected from measles infection up to their sixth month of life through antibodies, transferred by the placenta (transplacental).

Symptoms

Two stages, consequent upon each other, can be discerned with measles: the prodomal stage, proceeding with influenza-like symptoms and the exanthema stage with its characteristic skin lesions.

During a non-complicated course of the disease convalescence, recuperation follows the exanthema stage. The skin lesions fade and the skin scales. The other symptoms slowly disappear too. The recreation phase takes approximately two weeks.

Therapy

As with most virus infections, at present there is no measles specific drug available, in contrast to bacterial infections, where there are antibiotics. Therefore, therapy has to be effected symptomatically. Main focus are nursing measures and bed rest in darkened rooms because of the conjunctivitis.

Possible complications must be targeted directly. The outbreak of the disease can be stopped with non-immune people (people who have not been immunised) until up to the fourth day of the infection by giving antibodies (gammaglobubin).

Complications

Possible complications with measles occur relatively often, especially in children under the age of five years and adults over twenty years of age. Further danger of complications results from a temporary weakening of the immune defense.

Air passages, organs of the abdominal cavity and the brain can be affected by complications inflicted by the measles virus. Bronchits and pneunomia can develop in the air passages, both being responsible for up to 25% of death cases. At the abdominal cavity there is often a swelling of the lymph nodes, which causes great pain, can be registered. Of special meaning is the measles related appendicitis which in most cases requires an operation.

One greatly feared complication is a brain infection triggered by the measles, the measles encephalitis, which forms until up to ten days after the appearance of the exanthema. It occurs with roughly 0.1% of all cases and causes disturbance of consciousness, cramps, epileptic seizures as well as paralyzation. A few cases are at risk of permanent damages. These damages range from persistent paralyzation to mental disability. At around 25%, the death rate (mortality) of measles encephalitis is rather high. A rare complication is the subacute sclerosing panencephalitis (SSPE), a degenerative disease of the central nervous system (CNS) caused by the measles virus, which breaks out years later. It is lethal in almost all cases.

Prophylaxis/Protection

The only reliable prophylaxis against measles with its severe complications is the two times vaccination. It provides lifelong immunity. After many serious “children’s diseases” (eg. diphteria, whooping cough, polio) could be repressed through the consequential use of vaccination, measles at present are the most important vaccination preventable (preventable through vaccination) childhood disease.

The STIKO (permanent vaccination commission at the Robert Koch Institute in Berlin, Germany) recommends  vaccination against measles with a combined vaccine, which immunises against mumps and rubella as well (MMR vaccination). The correct point in time for the first MMR vaccination is at twelve months of age.

Before that, the maternal antibodies still present in the blood could endanger the success of the vaccination. The necessary second MMR vaccination can be given four weeks after the first vaccination at the earliest. However, it should have been carried out by the end of the second year of life at the latest, before the second birthday. Double-vaccination is essential since with five to ten percent of all children the active substances are not effective at the first time. These vaccinations can be caught up on at any age, there is no age limit for the measles (mumps, rubella) vaccination. In general, the costs for the vaccination are covered by the health insurance companies before the age of eighteen.

The vaccination is well compatible. Approximately 10% of vaccinations lead to light reactions within the first three days after the jab (light pain, red skin, swelling) at the point of injection. Between the seventh and twelfth day after the vaccination, light fever (15-20%) and light measles-style rash (5%) can occur. With one out of 3,000 vaccinated children, fever convulsions which are harmless in most cases appear. In order to eliminate this, the pediatrician might recommend taking an antipyretic medicine (suppository) after the seventh day following the vaccination.

Severe consequences of the vaccination are extremely rare, by far more scarce than with measles itself.   

Health authorities explicitly warn against so-called measles parties. At these parties healthy younger children are brought together with contaminated measles-infected children. That way the children are supposed to experience measles at an age where the frequency of especially dangerous side effects is inferior. In view of the still remaining risks of the measles disease and the availability of an effective and compatible vaccine, this practice is irresponsible.

The World Health Organization WHO has obligated its member countries to the goal to exterminate measles up to the year of 2010. To reach that goal, 95% of the population needs to be vaccinated. However, the vaccination rate in Germany does not hold out to that. In 2004, 93.5% of all school children received their first vaccination but only 65.7% received the second vaccination as well. There are especially high vaccination voids among the children who are today twelve up to eighteen years old.

Sources: Onmeda-Gesundheitsportal, Gesundheitsamt Köln, Focus-Online