A Tour around Measles
(Date of publication 20 February 2004)

"Measles - a childhood illness that more or less died out decades ago" just about sums up the public attitude to the disease in the developed world - and it is very mistaken. In Africa, measles remains the single leading cause of vaccine-preventable death among children, killing approximately half a million each year or 51 every hour. This is more than AIDS, tuberculosis or malnutrition. The Measles Initiative featured here aims to vaccinate 200 million African children and prevent 1.2 million deaths over five years. A similar campaign has been waged in North and South America for some years, and the Pan American Health Organization provides extensive coverage of it, including a weekly bulletin of confirmed cases in the region.

The incidence, symptoms and complications of measles are briefly outlined on the Wikipedia site, with plenty of links for those who want to explore the subject in more depth. After a 10-12 day incubation period, victims develop a fever, cough, runny nose, red eyes and a hypersensitivity to light. One of the first signs to appear is 'Koplik's Spots' - small, red, irregular spots with blue-white centres inside the mouth (see the photograph here). The characteristic red-brown rash then develops, usually starting at the hairline and spreading all over the body. It takes some 7 -10 days for the rash to fade, and after about 14 days all traces have gone.

The Centers for Disease Control (CDC) provides comprehensive details about many different aspects of measles in a .pdf file, such as that the primary site of infection is the respiratory epithelium of the nasopharynx, and that transmission is primarily person to person via large respiratory droplets. Here you will discover that the condition has no animal reservoir, some 30% of reported cases have one or more complications, and even in the USA there are one or two deaths for every thousand reported cases. The statistics regarding vaccination there are impressive; after the vaccine was licensed in 1963, the incidence of measles decreased by more than 98% and epidemics - which had previously occurred every 2-3 years - disappeared. Although there was a resurgence of cases between 1989 and 1991 when vaccination rates dropped to 50% in some areas, since 1997 there have been fewer than 200 cases per year, with only 86 in 2000, and most were imported from other countries. This compares with 3 - 4 million cases and 500 deaths each year before 1963. A physician's perspective on differential diagnosis, treatment and vaccination can be found on the eMedicine site.

The organism responsible is the rubeola virus , the sole member of the genus Morbillivirus which is a member of the family Paromyxoviridae. It is large, being 100 to 250 nanometres in diameter, roughly spherical in shape, and consists of six structural proteins. Although highly infectious - more than 80% of susceptible contacts develop the disease after exposure - it is highly susceptible to heat and also destroyed by solvents, acids, alkalis and both ultraviolet and visible light.

In emergency situations such as civil war or mass influx of refugees, measles is one of the five major causes of death, along with diarrhoea, malnutrition, malaria and pneumonia. Medecins Sans Frontieres describes how it manages an epidemic in such a situation and also how it prevented an outbreak in Rwanda by vaccinating 20,000 children in three days.

One of the most serious complications is bronchopneumonia, which is often localised to the bronchioles and surrounding alveoli. Symptoms include fever, chest pains and blood-streaked sputum. Brown Medical School provides basic notes, compares the condition with lobar pneumonia and includes some large micrographs on its site, while there is a photograph of a section through a lung with the condition here.

A more common but generally less serious sequela of measles is otitis media, or inflammation of the middle ear. The ear becomes very painful, hearing is reduced and the patient feels unwell, with a high temperature. Treatment is with nose drops and analgesics, plus antibiotics if there is secondary bacterial infection.

Measles vaccination is usually given as part of the MMR triple vaccine, which also protects against mumps and rubella. No tour around measles would be complete without covering the debate about possible dangers of this vaccine, which understandably causes parents a great deal of concern. Andrew Wakefield and colleagues at the Royal Free Hospital in London have suggested that MMR may cause inflammatory bowel disease, resulting in decreased intestinal absorption and possibly leading to developmental disorders such as autism.

An editorial from the Medical Journal of Australia argues that there is no evidence to support a causal relationship or to recommend administering the component vaccines separately. This view is corroborated by a review of the latest research which was commissioned in 2002 by the journal Nature. Among its findings were that Dr Wakefield's 1998 study did not meet the review's quality control criteria because it had no control group, the sample size was small, and its conclusions were based on surveying parents up to eight years after vaccination. Furthermore, none of the six studies which did meet its criteria showed any evidence of a link between MMR and autism or bowel problems. In November 2002 Danish researchers published a cohort study of 537,303 children which found no association between age at the time of vaccination, time since vaccination or date of vaccination, and the development of autistic disorder.

However, it has been claimed that respected researchers recently found elevated levels of measles antibodies in children with autism (compared to non-autistic children), indicating that they suffered an abnormal reaction to the measles element of the MMR vaccine.

If, however, the jury is still out on this issue there is no doubt about its effect in the UK ; reduced vaccination levels have led to larger outbreaks of measles which have spread more quickly and risk the permanent return of the disease to these shores.

Whilst most authorities agree that there is no cure for stammering and that it can only be controlled, a whole host of different causes has been postulated. Some of the old wives tales are so positively weird - go to the bottom of this page - that one can only speculate upon their origin. How could allowing an infant to look in the mirror, cutting its hair before it learns to speak, or tickling the soles of its feet possibly affect its powers of speech?

Turning to more scientifically plausible theories, two researchers in Utrecht have put forward the Vicious Circle Hypothesis. We all constantly monitor our own speech and stop, correct errors, backtrack and start again whenever necessary, creating minor dysfluencies such as hesitations, reformulations and repetitions. This hypothesis suggests that stammerers monitor their own speech too closely, identifying trivial irregularities. The detection itself creates an error, which is detected, creates an error, and so on, making the problem worse. Evidence supporting this view is that sufferers who perform an additional task while speaking, thereby distracting their attention, stammer significantly less.

At another page on the same site, Professor Webster of Brock University, Ontario, elucidates his theory, citing the research that underpins it. He believes that the speech centre of stammerers is located in the left cerebral hemisphere - as in fluent speakers - but that it is inefficient and unusually susceptible to interference from both hemispheres. Also, there is a lack of 'left hemisphere activation bias'; in fluent speakers the left hemisphere is in a greater state of readiness than the right, but in stammerers the balance is more equal, and it is known that activity in the frontal portion of the right hemisphere is associated with negative emotions such as fear and anxiety. Thus the fundamental cause is biological but the condition is reinforced psychologically. Recent research from Germany, involving sophisticated magnetic resonance imaging, appears to corroborate this to some extent, indicating that stuttering is associated with a structural abnormality in the left side of the brain.

A widely disseminated but scientifically unproven theory is that forwarded by William Parry, who attributes stammering to the Valsalva Manoeuvre, a natural mechanism which increases air pressure in the lungs in order to help exert physical effort or expel things from the body. One example is a weightlifter 'holding his breath' as he raises a barbell above his head. Muscles throughout the body are involved, but the relevant activity is that the larynx closes tightly around the upper airway to prevent air escaping from the lungs. This theory argues that when a stammerer anticipates a difficult word is needed, the need for extra effort is registered, triggering the Valsalva Manoeuvre and causing a stuttering block.

Professor Maguire of California University takes a different view, believing that the cause is a chemical imbalance in the brain, namely an excess of dopamine in the corpus striatum. This implies that drug treatment might provide the answer; haloperidol has been shown to reduce symptoms and Professor Maguire suggests that olanzapine, which he has used successfully, could prove effective.

Information about the best currently available therapies can be found at Stammering.net. These fall into four basic categories: self-therapy, electronic devices, speech language pathologists and speech clinics. It is emphasised that stammering is not only a speech disorder, but also a communication and behavioural disorder, and it cannot be eliminated overnight. Click here for a detailed review of electronic devices, which work by manipulating the stammerer's voice and relaying it back, and the neurological mechanisms involved.

Should you be really interested in this field, and its future development, there is a new quarterly online journal, Stammering Research, which was launched in April. The goal is to provide a forum for open exchange on relevant topics and to provoke strong debate from proponents of different theoretical positions.

Finally, here is a paradox from the UK. According the Disability Discrimination Act 1995, speech therapy which encourages stammerers not to avoid difficult words or to use substitution, thereby helping them to overcome their problem, could actually make them more likely to qualify as disabled and entitled to protection under its terms. Bizarre!

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