Measles (Rubeola)

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Measles (Rubeola)

Introduction

Disease History, Characteristics, and Transmission

Scope and Distribution

Treatment and Prevention

Impacts and Issues

Primary Source Connection

BIBLIOGRAPHY

Introduction

Measles is an acute viral illness that is one of the most common diseases of childhood, along with mumps and German measles (rubella). The clinical name for measles is rubeola, which comes from the Latin word ruber meaning red, and is a reference to the pinkish-red rash that is characteristic of the disease. Measles is a highly infectious disease, spread by coughs, sneezes, and person-to-person contact. It will occasionally lead to serious and even potentially fatal complications, such as pneumonia and encephalitis. Once someone has had measles, they are usually immune for life. Vaccination was introduced in the 1960s in the Western world and has led to a dramatic reduction in the number of children contracting measles. Since humans are the only hosts for the measles virus, it should be possible to eradicate measles, through universal vaccination. This requires a global effort to bring the vaccine to children everywhere.

Disease History, Characteristics, and Transmission

Measles is caused by a virus from the Paramyxoviridae family, which also includes the influenza and mumps viruses. It is a single stranded, enveloped, RNA virus— that is, its genetic material is RNA rather than DNA. The incubation time of the measles virus is 9–12 days. The virus first infects the epithelial cells lining the upper respiratory tract and then spreads to the rest of the body. In typical or natural measles, the early symptoms are like those of a common cold and include coughing, sneezing, sore throat, and fever. Within a few days, characteristic small white spots called Koplik's spots develop inside the mouth. A day or so later, a rash appears, starting behind the ears and spreading to the face and down the body and lasting for three or four days. Complications occur in up to 30% of cases of measles, and include pneumonia and otitis media, a middle ear infection that can lead to deafness. Encephalitis, an inflammation of the brain, is a complication in around one out of 1,000 cases of measles and has a 10% mortality rate. Mortality (death) from measles complications is highest among infants under two years old and in adults.

There is also a modified form of measles that occurs among those who have been incompletely vaccinated. Modified measles is less severe than typical measles and Koplik's spots may be absent. However, the risk of complications is the same. Rarely, a form of the disease called atypical measles may occur, usually among those who received vaccine in the 1960s. Atypical measles is characterized by sudden onset of fever, muscle pain, abdominal pain, and headache. Koplik's spots are rarely present and pneumonia is a common complication. Subacute sclerosing panencephalitis is an extremely rare degenerative disease of the brain and nervous system that is thought to arise from persistent measles infection in the brain. It occurs at a rate of around one per 100,000 cases and develops several years after measles exposure.

Measles is spread through the aerosol route—that is, through coughs and sneezes—and also by person-to-person contact. It is one of the most infectious diseases known, with around 90% of those being exposed becoming infected. A person is infectious for three to four days before the rash appears and for up to four days while the rash is present.

Scope and Distribution

Practically all children developed measles at some stage before vaccination, with the disease being most common in the winter and early spring. Before the introduction of the measles vaccine in 1963, there were 200,000–600,000 cases of measles a year in the United States, and this was probably a gross underestimate of the true scale of the disease. Before vaccination, measles killed more children than polio did. There was a sharp decline in measles cases following mass vaccination, followed by resurgence from 1983. This occurred among those who had not been vaccinated and among previously vaccinated teenagers. By 1989, there were 19,000 reported cases. A revised vaccination strategy, involving two doses instead of one, brought measles under control again. By 1993, cases were down to fewer than 1,000 annually in the United States. Measles has always been a global problem and has a major impact upon child health in developing countries, where vaccination is not readily available. According to the World Health Organization (WHO), there were around 30 million cases of measles around the world in 2004, of which 454,000 proved fatal. Measles can be dangerous to the fetus if a pregnant woman contracts measles in the first three months of pregnancy. Patients with weakened immunity, such as those with HIV/AIDS, are also at risk of complications from measles.

Treatment and Prevention

Treatment of measles is often unnecessary, although antibiotics may be given for secondary bacterial infections. Vitamin A may be useful in very severe cases and in countries where this vitamin deficiency is common. The antiviral drug ribavirin may be used in very severe cases also, and in patients with weakened immunity.

The spread of measles can be prevented by good hygiene, including handwashing. People with measles should isolate themselves while they are infectious and not attend school or day care. The best way of preventing measles is by vaccination. A killed vaccine was introduced in 1963, followed by a live vaccine from the late 1960s. It is now usual to give a combined measles, mumps, and rubella (MMR) vaccine—one dose between 12 and 15 months and a second before a child enters school. Most people can take MMR, but it is not usually recommended for people with weakened immunity or for pregnant women. Some parents have concerns over the safety of the MMR vaccine, because it has been linked with autism, and have refused vaccination for their children. In areas where vaccination rates have fallen, for this and other reasons, there have been new and significant measles outbreaks.

Impacts and Issues

Measles is the leading cause of vaccine-preventable death among children. The death rate from measles in developed countries is very low but reaches 1–5% in developing countries. The death rate from measles can be as high as 10–30% among malnourished children or those in refugee situations. Around 400,000 children under five years of age die from measles each year. But measles is a disease that could be eradicated from the planet, since humans are the virus’ only host. In 2001, the Measles Initiative was established by the American Red Cross, the Centers for Disease Control and Prevention, UNICEF (the United Nations Children's Fund), and the WHO. The Initiative aims to cut deaths from measles by 90% by 2010 compared to figures from the year 2000, using vaccination that can cost less than a dollar per child. In the first five years, the Initiative supported campaigns, with national governments, that led to the vaccination of more than 217 million children, mainly in Africa. This saw measles deaths in Africa drop by 75%—from 506,000 in 1999 to 126,000 in 2005. The Initiative has now expanded its vaccination activities to Asia and is working in all six WHO regions of the world in an attempt to eradicate measles and its impact on child health.

WORDS TO KNOW

AEROSOL: Particles of liquid or solid dispersed as a suspension in gas.

KOPLIK'S SPOTS: Koplik's spots, named after American pediatrician Henry Koplik (1858–1927) and also called Koplik's sign, are red spots with a small blue-white speck in the center found on the tongue and the insides of the cheeks during the early stages of measles.

MORTALITY: Mortality is the condition of being susceptible to death. The term “mortality” comes from the Latin word mors, which means “death.” Mortality can also refer to the rate of deaths caused by an illness or injury, i.e., “Rabies has a high mortality.”

Primary Source Connection

During the late 1970s and early 1980s, the rise of individualism and the popularity of self-help movements in the United States and Western Europe provided a new challenge to public health officials. Individuals began to take control of their own heath care and, in essence, some control and responsibility was wrested away from the physician and other health care workers. This presented a special challenge to public health agencies because a manifestation of the movement toward self directed health care also involved the rejection of traditional vaccinations such as the MMR vaccine.

Over the last decade, many parents further rejected using the MMR vaccine out of fears that the vaccine was linked to autism.

The newspaper article by Mark Porter and commentary below demonstrate different aspects of the scientific and social debate over the MMR vaccine. The article also demonstrates the attempts by scientific community to be both self-correcting and to discipline breeches of ethics. The commentary offers a view that although the original research linking the MMR vaccine to autism appears tainted, the vigorous investigation might lead to future benefits in the way vaccines are developed and tested.

Mark Porter is is a medical doctor who provides regular advice and commentary on medical issues for radio and television programming in the United Kingdom.

Doctor Who Sparked the MMR Debate Faces Misconduct Charge

THE doctor whose research sparked the international scare over the safety of the MMR vaccine is to be charged with serious professional misconduct.

Andrew Wakefield is to be ordered in front of the General Medical Council after publishing a paper in The Lancet in 1998 that suggested a link between the jab and autism as well as Crohn's, a bowel disease.

A sheet of preliminary charges accuses him of putting out “inadequately founded” research, of failing to obtain ethical committee approval, obtaining funding “improperly” and of subjecting children to “unnecessary and invasive investigations.”

Dr. Wakefield's study is held responsible by many doctors for a dramatic slump in the number of parents allowing their children to have the combined injection against measles, mumps and rubella.

Take-up of the vaccination has fallen to only 12 per cent of children in some areas of London, while city-wide little more than half are having the jab - putting an estimated 100,000 of London children at risk of infection.

In 2004, The Lancet withdrew the paper, with the editor declaring it “fatally flawed” after it emerged Dr. Wakefield had been paid [pounds sterling]55,000 (more than $100,000) by lawyers for parents of children who claimed they had been damaged by the MMR vaccine to look for evidence that could be used in legal action. GMC lawyers are working on the list of charges with a hearing expected next year. If found guilty of serious professional misconduct Dr. Wakefield, 50, faces being struck from the medical register. The GMC decided to bring a case against the doctor contrary to normal procedures. It usually only brings charges when it receives a complaint, but in this case it acted without one, following a two-year investigation.

Why we all owe Wakefield a debt of thanks

COMMENTARY

DR ANDREW WAKEFIELD has had a spectacular fall from grace.

Eight years after sparking worldwide concern about the safety of the MMR vaccine, his research has been rejected by the journal that originally published it, and most of his fellow researchers have distanced themselves from his conclusions.

A promising career in the UK has come to an abrupt end and he has left the country. To cap it all, he is set to be charged with professional misconduct by the General Medical Council. While intrigued by Wakefield's theory that exposure to the measles virus could predispose some children to autism, I have always felt that he was wrong to cast doubts on the safety of MMR without more evidence.

But just because we didn't see eye to eye it doesn't mean that I am comfortable with the public pillorying that he has recently endured. Indeed, I am distinctly uncomfortable with it. We need mavericks like Andrew Wakefield, and his plight can only stifle the sort of independent thinking required to make major breakthroughs in medicine. History has taught us that there is a fine line between being dismissed as an eccentric and being lauded as a genius. Nobel Prize winner Dr. Barry Marshall is a case in point.

At first Dr Marshall's claims that stomach and duodenal ulcers were caused by an infection (H.pylori) and could be treated with antibiotics, rather than a lifetime of acid suppressing drugs, were treated with derision.

But he persevered.

Fifteen years later his discovery has transformed the lives of millions of patients and he has become one of medicine's most distinguished academics.

While Dr. Wakefield has achieved notoriety rather than eminence, his enthusiasm left me in little doubt that he really did believe he had stumbled across something that questioned the safety of the MMR vaccine. Time may have proved him wrong, but back in 1998 when he first raised the possibility, we simply didn't have enough data to back the bland reassurances issued by the Department of Health.

Thanks to him sticking his head above the parapet, we now know far more about the MMR vaccine than we ever would have known had he not questioned its safety.

And I suspect the resulting scepticism, both lay and professional, that now surrounds the introduction of new vaccines will benefit us all in the long-term.

IN CONTEXT: SCIENTIFIC, POLITICAL, AND ETHICAL ISSUES

With regard to a potential connection between the measles, mumps, and rubella vaccine (MMR vaccine) and autism, scientists at the National Immunization Program (NIP) at Centers for Disease Control and Prevention (CDC) state that “the weight of currently available scientific evidence does not support the hypothesis that MMR vaccine causes autism. CDC recognizes there is considerable public interest in this issue, and therefore supports additional research regarding this hypothesis. CDC is committed to maintaining the safest, most effective vaccine supply in history.”

As of May 2007 the CDC further states that, “there is no convincing evidence that vaccines such as MMR cause long term health effects. On the other hand, we do know that people will become ill and some will die from the diseases this vaccine prevents. Measles outbreaks have recently occurred in the UK and Germany following an increase in the number of parents who chose not to have their children vaccinated with the MMR vaccine. Discontinuing a vaccine program based on unproven theories would not be in anyone's best interest. Isolated reports about these vaccines causing long term health problems may sound alarming at first. However, careful review of the science reveals that these reports are isolated and not confirmed by scientifically sound research. Detailed medical reviews of health effects reported after receipt of vaccines have often proven to be unrelated to vaccines, but rather have been related to other health factors. Because these vaccines are recommended widely to protect the health of the public, research on any serious hypotheses about their safety are important to pursue. Several studies are underway to investigate still unproven theories about vaccinations and severe side effects.”

SOURCE: Centers for Disease Control and Prevention, National Immunization Program

Mark Porter

PORTER, MARK. “DOCTOR WHO SPARKED THE MMR DEBATE FACES MISCONDUCT CHARGE.” THE EVENING STANDARD. JUNE 12, 2006.

See AlsoChildhood Infectious Diseases, Immunization Impacts; Mumps; Rubella.