Measles
Encyclopedia
Measles, also known as rubeola or morbilli, is an infection of the respiratory system caused by a virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

, specifically a paramyxovirus
Paramyxovirus
Paramyxoviruses are viruses of the Paramyxoviridae family of the Mononegavirales order; they are negative-sense single-stranded RNA viruses responsible for a number of human and animal diseases.-Genera:*Subfamily Paramyxovirinae**Genus Avulavirus Paramyxoviruses (from Greek para-, beyond, -myxo-,...

 of the genus Morbillivirus
Morbillivirus
Morbillivirus is a genus belonging to the Paramyxoviridae family of viruses in the order Mononegavirales. Many members of the genus cause diseases, such as rinderpest and measles, and are highly infectious.- External links :* *...

. Morbilliviruses, like other paramyxoviruses, are enveloped, single-stranded, negative-sense RNA viruses. Symptoms include fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...

, cough
Cough
A cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes...

, runny nose
Coryza
Coryza is a word describing the symptoms of a head cold. It describes the inflammation of the mucous membranes lining the nasal cavity which usually gives rise to the symptoms of nasal congestion and loss of smell, among other symptoms...

, red eyes
Conjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...

 and a generalized, maculopapular
Maculopapular rash
A maculopapular rash is a type of rash characterized by a flat, red area on the skin that is covered with small confluent bumps. The term "maculopapular" is a compound: macules are small, flat discolored spots on the surface of the skin; and papules are small, raised bumps...

, erythema
Erythema
Erythema is redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. It occurs with any skin injury, infection, or inflammation...

tous rash.

Measles (also sometimes known as English Measles) is spread through respiration (contact with fluid
Fluid
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....

s from an infected
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...

 person's nose and mouth, either directly or through aerosol transmission), and is highly contagious—90% of people without immunity
Immune system
An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

 sharing living space with an infected person will catch it. An asymptomatic incubation period occurs nine to twelve days from initial exposure and infectivity
Infectivity
In epidemiology, infectivity refers to the ability of a pathogen to establish an infection. More specifically, infectivity is a pathogen's capacity for horizontal transmission that is, how frequently it spreads among hosts that are not in a parent-child relationship...

 lasts from two to four days prior, until two to five days following the onset of the rash (i.e. four to nine days infectivity in total).

An alternative name for measles in English-speaking countries is rubeola, which is sometimes confused with rubella
Rubella
Rubella, commonly known as German measles, is a disease caused by the rubella virus. The name "rubella" is derived from the Latin, meaning little red. Rubella is also known as German measles because the disease was first described by German physicians in the mid-eighteenth century. This disease is...

 (German measles); the diseases are unrelated.

Signs and symptoms

The classical symptoms of measles include four-day fevers and the three Cs—cough
Cough
A cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes...

, coryza
Coryza
Coryza is a word describing the symptoms of a head cold. It describes the inflammation of the mucous membranes lining the nasal cavity which usually gives rise to the symptoms of nasal congestion and loss of smell, among other symptoms...

 (head cold) and conjunctivitis
Conjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...

 (red eyes). The fever may reach up to 40 °C
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...

 (104 °F
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...

). Koplik's spots
Koplik's spots
Koplik spots are a prodromic viral enanthem of measles manifesting two days before the measles rash itself. They are characterized as clustered, white lesions on the buccal mucosa near each Stenson's duct and are pathognomonic for measles...

 seen inside the mouth are pathognomonic
Pathognomonic
Pathognomonic is a term, often used in medicine, that means characteristic for a particular disease. A pathognomonic sign is a particular sign whose presence means that a particular disease is present beyond any doubt...

 (diagnostic) for measles, but are not often seen, even in real cases of measles, because they are transient and may disappear within a day of arising.

The characteristic measles rash is classically described as a generalized, maculopapular
Maculopapular rash
A maculopapular rash is a type of rash characterized by a flat, red area on the skin that is covered with small confluent bumps. The term "maculopapular" is a compound: macules are small, flat discolored spots on the surface of the skin; and papules are small, raised bumps...

, erythema
Erythema
Erythema is redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. It occurs with any skin injury, infection, or inflammation...

tous rash that begins several days after the fever starts. It starts on the head before spreading to cover most of the body, often causing itch
Itch
Itch is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to classify it as any one type of sensory experience. Modern science has shown that itch has many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response...

ing. The rash is said to "stain", changing color from red to dark brown, before disappearing. The measles rash appears two to four days after initial symptoms, and lasts for up to eight days.

Complications

Complications with measles are relatively common, ranging from relatively mild and less serious diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...

, to pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...

, Otitis media
Otitis media
Otitis media is inflammation of the middle ear, or a middle ear infection.It occurs in the area between the tympanic membrane and the inner ear, including a duct known as the eustachian tube. It is one of the two categories of ear inflammation that can underlie what is commonly called an earache,...

 and acute encephalitis
Encephalitis
Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...

 (and rarely subacute sclerosing panencephalitis
Subacute sclerosing panencephalitis
Subacute sclerosing panencephalitis is a rare chronic, progressive encephalitis that affects primarily children and young adults, caused by a persistent infection of immune resistant measles virus . No cure for SSPE exists, but the condition can be managed by medication if treatment is started at...

); corneal ulcer
Corneal ulcer
A corneal ulcer, or ulcerative keratitis, is an inflammatory condition of the cornea involving loss of its outer layer. It is very common in dogs and is sometimes seen in cats...

ation leading to corneal scarring
Corneal abrasion
Corneal abrasion is a medical condition involving the loss of the surface epithelial layer of the eye's cornea.-Symptoms and signs:Symptoms of corneal abrasion include pain, photophobia, a foreign-body sensation, excessive squinting, and a reflex production of tears...

. Complications are usually more severe in adults who catch the virus.

Between the years 1987 and 2000, the case fatality rate across the United States was three measles-attributable deaths per 1000 cases, or 0.3%.
In underdeveloped nation
Developing country
A developing country, also known as a less-developed country, is a nation with a low level of material well-being. Since no single definition of the term developing country is recognized internationally, the levels of development may vary widely within so-called developing countries...

s with high rates of malnutrition
Malnutrition
Malnutrition is the condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess , or in the wrong proportions....

 and poor healthcare, fatality rates have been as high as 28%. In immunocompromised
Immunodeficiency
Immunodeficiency is a state in which the immune system's ability to fight infectious disease is compromised or entirely absent. Immunodeficiency may also decrease cancer immunosurveillance. Most cases of immunodeficiency are acquired but some people are born with defects in their immune system,...

 patients (e.g. people with AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...

) the fatality rate is approximately 30%.

Cause

Measles is caused by the measles virus, a single-stranded, negative-sense enveloped RNA virus of the genus Morbillivirus
Morbillivirus
Morbillivirus is a genus belonging to the Paramyxoviridae family of viruses in the order Mononegavirales. Many members of the genus cause diseases, such as rinderpest and measles, and are highly infectious.- External links :* *...

 within the family Paramyxoviridae. Humans are the natural hosts of the virus; no animal reservoirs are known to exist. This highly contagious virus is spread by coughing and sneezing via close personal contact or direct contact with secretions.

Risk factors for measles virus infection include the following:
  • Children with immunodeficiency due to HIV or AIDS, leukemia, alkylating agents, or corticosteroid therapy, regardless of immunization status

  • Travel to areas where measles is endemic or contact with travelers to endemic areas

Infants who lose passive antibody before the age of routine immunization

Risk factors for severe measles and its complications include the following:
  • Malnutrition
  • Underlying immunodeficiency
  • Pregnancy
  • Vitamin A deficiency

Diagnosis

Clinical diagnosis of measles requires a history of fever of at least three days, with at least one of the three C's (cough, coryza, conjunctivitis). Observation of Koplik's spots
Koplik's spots
Koplik spots are a prodromic viral enanthem of measles manifesting two days before the measles rash itself. They are characterized as clustered, white lesions on the buccal mucosa near each Stenson's duct and are pathognomonic for measles...

 is also diagnostic of measles.

Alternatively, laboratory diagnosis of measles can be done with confirmation of positive measles IgM
IGM
IGM as an acronym or abbreviation can refer to:* Immunoglobulin M , the primary antibody against A and B antigens on red blood cells* International Grandmaster, a chess ranking* intergalactic medium* Intragroup medium - see: Intracluster medium...

 antibodies or isolation of measles virus RNA from respiratory specimens. In patients where phlebotomy
Venipuncture
In medicine, venepuncture, venopuncture or venipuncture is the process of obtaining intravenous access for the purpose of intravenous therapy or for blood sampling of venous blood. This procedure is performed by medical laboratory scientists, medical practitioners, some EMTs, paramedics,...

 not possible, saliva can be collected for salivary measles-specific IgA
IGA
Iga or IGA may stand for:-Given name:* a female given name of Polish origin. The name originates from the female given name Jadwiga and stands for gia,or gina in the USA....

 testing. Positive contact with other patients known to have measles adds strong epidemiological
Epidemiology
Epidemiology is the study of health-event, health-characteristic, or health-determinant patterns in a population. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive...

 evidence to the diagnosis. The contact with any infected person in any way, including semen through sex, saliva, or mucus, can cause infection.

Prevention

In developed countries, most children are immunized against measles by the age of 18 months, generally as part of a three-part MMR vaccine
MMR vaccine
The MMR vaccine is an immunization shot against measles, mumps, and rubella . It was first developed by Maurice Hilleman while at Merck in the late 1960s....

 (measles, mumps
Mumps
Mumps is a viral disease of the human species, caused by the mumps virus. Before the development of vaccination and the introduction of a vaccine, it was a common childhood disease worldwide...

, and rubella
Rubella
Rubella, commonly known as German measles, is a disease caused by the rubella virus. The name "rubella" is derived from the Latin, meaning little red. Rubella is also known as German measles because the disease was first described by German physicians in the mid-eighteenth century. This disease is...

). The vaccination is generally not given earlier than this because children younger than 18 months usually retain antimeasles immunoglobulins (antibodies) transmitted from the mother during pregnancy. A second dose is usually given to children between the ages of four and five, to increase rates of immunity. Vaccination rates have been high enough to make measles relatively uncommon. Even a single case in a college dormitory or similar setting is often met with a local vaccination program, in case any of the people exposed are not already immune.

In developing countries where measles is highly endemic
Endemic (epidemiology)
In epidemiology, an infection is said to be endemic in a population when that infection is maintained in the population without the need for external inputs. For example, chickenpox is endemic in the UK, but malaria is not...

, WHO
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 doctors recommend two doses of vaccine
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...

 be given at six and nine months of age. The vaccine should be given whether the child is HIV-infected or not. The vaccine is less effective in HIV-infected infants, but the risk of adverse reactions is low. Measles vaccination programs are often used to deliver other child health interventions, as well, such as bed nets to protect against malaria, antiparasite medicine and vitamin A supplements, and so contribute to the reduction of child deaths from other causes.

Unvaccinated populations are at risk for the disease. Traditionally low vaccination rates in northern Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...

 dropped further in the early 2000s when radical preachers promoted a rumor that polio vaccines were a Western plot to sterilize Muslims and infect them with HIV. The number of cases of measles rose significantly, and hundreds of children died.

Claims of a connection between the MMR vaccine and autism were raised in a 1998 paper in The Lancet
The Lancet
The Lancet is a weekly peer-reviewed general medical journal. It is one of the world's best known, oldest, and most respected general medical journals...

, a respected British medical journal
Medical journal
A public health journal is a scientific journal devoted to the field of public health, including epidemiology, biostatistics, and health care . Public health journals, like most scientific journals, are peer-reviewed...

. Later investigation by Sunday Times
The Sunday Times
The Sunday Times is a British Sunday newspaper.The Sunday Times may also refer to:*The Sunday Times *The Sunday Times *The Sunday Times *The Sunday Times...

journalist Brian Deer
Brian Deer
Brian Deer is a British investigative reporter, best known for inquiries into the drug industry, medicine and social issues for the Sunday Times of London.- Career :...

 discovered the lead author of the article, Andrew Wakefield
Andrew Wakefield
Andrew Wakefield is a British former surgeon and medical researcher, known as an advocate for the discredited claim that there is a link between the measles, mumps and rubella vaccine, autism and bowel disease, and for his fraudulent 1998 research paper in support of that claim.Four years after...

, had multiple undeclared conflicts of interest
Conflicts of Interest
"Conflicts of Interest" is an episode from the fourth season of the science fiction television series Babylon 5.-Arc significance:* Garibaldi begins to work for William Edgars. In the process Garibaldi is reintroduced to his ex-girlfriend, Lise, who is currently married to Edgars.* The "Voice of...

, and had broken other ethical codes. The Lancet paper was later retracted, and Wakefield was found guilty by the General Medical Council
General Medical Council
The General Medical Council registers and regulates doctors practising in the United Kingdom. It has the power to revoke or restrict a doctor's registration if it deems them unfit to practise...

 of serious professional misconduct in May 2010, and was struck off the Medical Register, meaning he could no longer practise as a doctor in the UK. The research was declared fraudulent in 2011 by the BMJ
BMJ
BMJ is a partially open-access peer-reviewed medical journal. Originally called the British Medical Journal, the title was officially shortened to BMJ in 1988. The journal is published by the BMJ Group, a wholly owned subsidiary of the British Medical Association...

. Scientific evidence
Evidence-based medicine
Evidence-based medicine or evidence-based practice aims to apply the best available evidence gained from the scientific method to clinical decision making. It seeks to assess the strength of evidence of the risks and benefits of treatments and diagnostic tests...

 provides no support for the hypothesis that MMR plays a role in causing autism.

In January 2010, a study of Polish children found vaccination with the measles, mumps, and rubella vaccine was not a risk factor for development of autistic disorder; in fact, the vaccinated patients had a slightly reduced risk of autistic disorder, although the mechanism of action is unknown, and the result may have been coincidental. The autism-related MMR study in Britain caused use of the vaccine to plunge, and measles cases came back: 2007 saw 971 cases in England and Wales, the biggest rise in occurrence in measles cases since records began in 1995. A 2005 measles outbreak in Indiana
Indiana
Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...

 was attributed to children whose parents refused vaccination.

Treatment

There is no specific treatment for measles. Most patients with uncomplicated measles will recover with rest and supportive treatment. It is, however, important to seek medical advice if the patient becomes more unwell, as they may be developing complications.

Some patients will develop pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...

 as a sequel to the measles. Other complications include ear infections, bronchitis
Bronchitis
Acute bronchitis is an inflammation of the large bronchi in the lungs that is usually caused by viruses or bacteria and may last several days or weeks. Characteristic symptoms include cough, sputum production, and shortness of breath and wheezing related to the obstruction of the inflamed airways...

, and encephalitis
Encephalitis
Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...

. Acute measles encephalitis has a mortality rate of 15%. While there is no specific treatment for measles encephalitis, antibiotics are required for bacterial pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung—especially affecting the microscopic air sacs —associated with fever, chest symptoms, and a lack of air space on a chest X-ray. Pneumonia is typically caused by an infection but there are a number of other causes...

, sinusitis
Sinusitis
Sinusitis is inflammation of the paranasal sinuses, which may be due to infection, allergy, or autoimmune issues. Most cases are due to a viral infection and resolve over the course of 10 days...

, and bronchitis
Bronchitis
Acute bronchitis is an inflammation of the large bronchi in the lungs that is usually caused by viruses or bacteria and may last several days or weeks. Characteristic symptoms include cough, sputum production, and shortness of breath and wheezing related to the obstruction of the inflamed airways...

 that can follow measles.

All other treatment addresses symptoms, with ibuprofen
Ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug used for relief of symptoms of arthritis, fever, as an analgesic , especially where there is an inflammatory component, and dysmenorrhea....

, or acetaminophen (paracetamol) to reduce fever and pain and, if required, a fast-acting bronchodilator for cough. As for aspirin
Aspirin
Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...

, some research has suggested a correlation between children who take aspirin and the development of Reye's syndrome
Reye's syndrome
Reye's syndrome is a potentially fatal disease that causes numerous detrimental effects to many organs, especially the brain and liver, as well as causing a lower than usual level of blood sugar . The classic features are liver damage, aspirin use and a viral infection...

. Some research has shown aspirin may not be the only medication associated with Reye's, and even antiemetics have been implicated, with the point being the link between aspirin use in children and Reye's syndrome development is weak at best, if not actually nonexistent. Nevertheless, most health authorities still caution against the use of aspirin for any fevers in children under 16.

The use of vitamin A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...

 in treatment has been investigated. A systematic review of trials into its use found no significant reduction in overall mortality, but it did reduce mortality in children aged under two years.

Prognosis

While the vast majority of patients survive measles, complications occur fairly frequently, and may include bronchitis, and panencephalitis
Subacute sclerosing panencephalitis
Subacute sclerosing panencephalitis is a rare chronic, progressive encephalitis that affects primarily children and young adults, caused by a persistent infection of immune resistant measles virus . No cure for SSPE exists, but the condition can be managed by medication if treatment is started at...

 which is potentially fatal. Also, even if the patient is not concerned about death or sequela
Sequela
A sequela) is a pathological condition resulting from a disease, injury, or other trauma.Chronic kidney disease, for example, is sometimes a sequela of diabetes, and neck pain is a common sequela of whiplash or other trauma to the cervical vertebrae. Post-traumatic stress disorder may be a...

 from the measles, the person may spread the disease to an immunocompromised patient, for whom the risk of death is much higher, due to complications such as giant cell pneumonia. Acute measles encephalitis is another serious risk of measles virus infection. It typically occurs two days to one week after the breakout of the measles exanthem
Exanthem
An exanthem is a widespread rash usually occurring in children. Exanthems can be caused by toxins or drugs, microorganisms, or can result from autoimmune disease.It can be contrasted with an enanthem.-Types:...

, and begins with very high fever, severe headache, convulsions, and altered mentation. Patient may become comatose, and death or brain injury may occur.

Epidemiology

Mortality in developed countries is ~1/1000. In sub-Saharan Africa, mortality is10%. In cases with complications, the rate may rise to 20–30%. On average, ~450 children die every day from measles.

Even in countries where vaccination has been introduced, rates may remain high. In Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

, vaccination was introduced in 1985. The number of cases was 99,903 in that year. Within two years, the number of cases had fallen to 201, but this fall was not sustained: case numbers in 1989, 1993 and 2000 were 1,248, 4,328 and 1,603, respectively. This country's example illustrates the need for vaccination rates greater than 95% to prevent the spread of measles.

According to the WHO, measles is a leading cause of vaccine-preventable childhood mortality. Worldwide, the fatality rate has been significantly reduced by a vaccination campaign led by partners in the Measles Initiative
Measles Initiative
Measles Initiative , launched in 2001, is a long-term commitment and partnership among leaders in public health and supports the goal of reducing measles deaths globally by 90% by 2010 compared to 2000 estimates.-Impact:...

: the American Red Cross
American Red Cross
The American Red Cross , also known as the American National Red Cross, is a volunteer-led, humanitarian organization that provides emergency assistance, disaster relief and education inside the United States. It is the designated U.S...

, the United States Centers for Disease Control and Prevention (CDC), the United Nations Foundation, UNICEF and the WHO. Globally, measles fell 60% from an estimated 873,000 deaths in 1999 to 345,000 in 2005. Estimates for 2008 indicate deaths fell further to 164,000 globally, with 77% of the remaining measles deaths in 2008 occurring within the Southeast Asian region.

Five out of six WHO regions have set goals to eliminate measles, and at the 63rd World Health Assembly in May 2010, delegates agreed a global target of a 95% reduction in measles mortality by 2015 from the level seen in 2000, as well as to move towards eventual eradication
Eradication of infectious diseases
Eradication is the reduction of an infectious disease's prevalence in the global host population to zero. It is sometimes confused with elimination, which describes either the reduction of an infectious disease's prevalence in a regional population to zero, or the reduction of the global prevalence...

. However, no specific global target date for eradication has yet been agreed to as of May 2010.

Evolution

The measles virus evolved from the then-widespread rinderpest
Rinderpest
Rinderpest was an infectious viral disease of cattle, domestic buffalo, and some other species of even-toed ungulates, including buffaloes, large antelopes and deer, giraffes, wildebeests and warthogs. After a global eradication campaign, the last confirmed case of rinderpest was diagnosed in 2001...

 virus, most probably in the 11th and 12th centuries. The earliest likely origin is within the seventh century: for this earlier origin there is some linguistic evidence. The current epidemic strain evolved at the beginning of the 20th century – most probably between 1908 and 1943.

History

The Antonine Plague
Antonine Plague
The Antonine Plague, AD 165–180, also known as the Plague of Galen, who described it, was an ancient pandemic, either of smallpox or measles, brought back to the Roman Empire by troops returning from campaigns in the Near East...

, 165–180 AD, also known as the Plague of Galen
Galen
Aelius Galenus or Claudius Galenus , better known as Galen of Pergamon , was a prominent Roman physician, surgeon and philosopher...

, who described it, was probably smallpox
Smallpox
Smallpox was an infectious disease unique to humans, caused by either of two virus variants, Variola major and Variola minor. The disease is also known by the Latin names Variola or Variola vera, which is a derivative of the Latin varius, meaning "spotted", or varus, meaning "pimple"...

 or measles. The disease killed as many as one-third of the population in some areas, and decimated the Roman
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....

 army. Estimates of the timing of evolution of measles seem to suggest this plague was something other than measles. The first scientific description of measles and its distinction from smallpox and chickenpox
Chickenpox
Chickenpox or chicken pox is a highly contagious illness caused by primary infection with varicella zoster virus . It usually starts with vesicular skin rash mainly on the body and head rather than at the periphery and becomes itchy, raw pockmarks, which mostly heal without scarring...

 is credited to the Persian physician, Muhammad ibn Zakariya ar-Razi (860–932), known to the West as "Rhazes", who published The Book of Smallpox and Measles (in Arabic
Arabic language
Arabic is a name applied to the descendants of the Classical Arabic language of the 6th century AD, used most prominently in the Quran, the Islamic Holy Book...

: Kitab fi al-jadari wa-al-hasbah). Given what is now known about the evolution of measles, this account is remarkably timely.

Measles is an endemic disease, meaning it has been continually present in a community, and many people develop resistance. In populations not exposed to measles, exposure to a new disease can be devastating. In 1529, a measles outbreak in Cuba
Cuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...

 killed two-thirds of the natives who had previously survived smallpox. Two years later, measles was responsible for the deaths of half the population of Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...

, and had ravaged Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

, and the Inca civilization.

In roughly the last 150 years, measles has been estimated to have killed about 200 million people worldwide. During the 1850s, measles killed a fifth of Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

's people. In 1875, measles killed over 40,000 Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...

ans, approximately one-third of the population. In the 19th century, the disease decimated the Andamanese
Andamanese
The Andamanese people are the various aboriginal inhabitants of the Andaman Islands, which is the northern district of the Andaman and Nicobar Islands union territory of India, located in the southeastern part of the Bay of Bengal. They include the Great Andamanese, Jarawa, Onge, Sentinelese, and...

 population. In 1954, the virus causing the disease was isolated from an 11-year old boy from the United States, David Edmonston, and adapted and propagated on chick
Chicken
The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...

 embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...

 tissue culture
Tissue culture
Tissue culture is the growth of tissues or cells separate from the organism. This is typically facilitated via use of a liquid, semi-solid, or solid growth medium, such as broth or agar...

. To date, 21 strains of the measles virus have been identified. While at Merck
Merck & Co.
Merck & Co., Inc. , also known as Merck Sharp & Dohme or MSD outside the United States and Canada, is one of the largest pharmaceutical companies in the world. The Merck headquarters is located in Whitehouse Station, New Jersey, an unincorporated area in Readington Township...

, Maurice Hilleman
Maurice Hilleman
Maurice Ralph Hilleman was an American microbiologist who specialized in vaccinology and developed over three dozen vaccines, more than any other scientist...

 developed the first successful vaccine. Licensed vaccine
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...

s to prevent the disease became available in 1963.

Recent outbreaks

Since the beginning of September, 2009, Johannesburg
Johannesburg
Johannesburg also known as Jozi, Jo'burg or Egoli, is the largest city in South Africa, by population. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, having the largest economy of any metropolitan region in Sub-Saharan Africa...

, a city in Gauteng
Gauteng
Gauteng is one of the nine provinces of South Africa. It was formed from part of the old Transvaal Province after South Africa's first all-race elections on 27 April 1994...

, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

 reported about 48 cases of measles. Soon after the outbreak, the government ordered all children to be vaccinated. Vaccination programs were then initiated in all schools, and parents of young children were advised to have them vaccinated. Many people were not willing to have the vaccination done, as it is believed to be unsafe and ineffective. The Health Department assured the public that their program was indeed safe. Speculation arose as to whether or not new needles were being used. By mid-October, there were at least 940 recorded cases, and four deaths.

On February 19, 2009, 505 measles cases were reported in twelve provinces in northern Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

, with Hanoi
Hanoi
Hanoi , is the capital of Vietnam and the country's second largest city. Its population in 2009 was estimated at 2.6 million for urban districts, 6.5 million for the metropolitan jurisdiction. From 1010 until 1802, it was the most important political centre of Vietnam...

 accounting for 160 cases. A high rate of complications, including meningitis
Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...

 and encephalitis
Encephalitis
Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...

, has worried health workers, and the U.S. CDC recommended all travelers be immune to measles.

On 1 April 2009, the disease broke out in two schools in North Wales. Ysgol John Bright
Ysgol John Bright
Ysgol John Bright is a secondary school on Maesdu Road, Llandudno in Conwy County Borough, Wales. It serves the state secondary education sector in the Llandudno area and has around 1200 pupils. The school was recently rebuilt and opened in September 2004...

 and Ysgol Ffordd Dyffryn, two schools in Wales
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

, have had the outbreak and are making sure every pupil has had the measles vaccine
Measles vaccine
Measles vaccine is a highly effective vaccine used against measles. The measles-mumps-rubella-varicella combo vaccine has been available since 2005...

.

In 2007, a large outbreak in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 caused a number of universities and other institutions to close in an attempt to contain the disease.

Approximately 1000 cases of the disease were reported in Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

 between August 2007 and May 2008 (in sharp contrast to just some dozen cases the year before). Many children in ultra-Orthodox Jewish communities were affected due to low vaccination coverage. As of 2008, the disease is endemic
Endemic (epidemiology)
In epidemiology, an infection is said to be endemic in a population when that infection is maintained in the population without the need for external inputs. For example, chickenpox is endemic in the UK, but malaria is not...

 in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, with 1,217 cases diagnosed in 2008,

and epidemics have been reported in Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

, Italy
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 and Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

.

In March 2010, the Philippines declared an epidemic due to the continuously rising cases of measles.

As of May 2011, over 17,000 cases of measles have so far been reported from France between January 2008 and April 2011, including 2 deaths in 2010 and 6 deaths in 2011. Over 7,500 of these cases fell in the first three months of 2011, and Spain, Turkey, Macedonia, and Belgium have been among the other European countries reporting further smaller outbreaks. The French outbreak has been specifically linked to a further outbreak in Quebec in 2011, where 327 cases have been reported between January and June 1, 2011, and the European outbreaks in general have also been implicated in further small outbreaks in the USA, where 40 separate importations from the European region had been reported between January 1 and May 20.

As of July 2011, 1,145 children have died of 115 600 cases in the DRC, which is also battling deadly outbreaks of cholera
Cholera
Cholera is an infection of the small intestine that is caused by the bacterium Vibrio cholerae. The main symptoms are profuse watery diarrhea and vomiting. Transmission occurs primarily by drinking or eating water or food that has been contaminated by the diarrhea of an infected person or the feces...

 and polio.

In August 2011, an outbreak in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 has seen 94 confirmed cases in Auckland
Auckland
The Auckland metropolitan area , in the North Island of New Zealand, is the largest and most populous urban area in the country with residents, percent of the country's population. Auckland also has the largest Polynesian population of any city in the world...

 alone.

In November 2011, an outbreak was reported in Canberra
Canberra
Canberra is the capital city of Australia. With a population of over 345,000, it is Australia's largest inland city and the eighth-largest city overall. The city is located at the northern end of the Australian Capital Territory , south-west of Sydney, and north-east of Melbourne...

, the capital city of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 with at least 12 reported cases.

The Americas

Indigenous measles were declared to have been eliminated in North, Central, and South America; the last endemic case in the region was reported on November 12, 2002, with only northern Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and rural Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, particularly in the provinces of Ontario, Quebec, and Alberta, having minor endemic status. Outbreaks are still occurring, however, following importations of measles viruses from other world regions. In June 2006, an outbreak in Boston
Boston
Boston is the capital of and largest city in Massachusetts, and is one of the oldest cities in the United States. The largest city in New England, Boston is regarded as the unofficial "Capital of New England" for its economic and cultural impact on the entire New England region. The city proper had...

 resulted after a resident became infected in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, and in October 2007, a Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....

 girl who had been vaccinated contracted the disease in Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....

.

Between January 1 and April 25, 2008, a total of 64 confirmed measles cases were preliminarily reported in the United States to the CDC, the most reported by this date for any year since 2001. Of the 64 cases, 54 were associated with importation of measles from other countries into the United States, and 63 of the 64 patients were unvaccinated or had unknown or undocumented vaccination status.

By July 9, 2008, a total of 127 cases were reported in 15 states (including 22 in Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

), making it the largest U.S. outbreak since 1997 (when 138 cases were reported). Most of the cases were acquired outside of the United States and afflicted individuals who had not been vaccinated.

By July 30, 2008, the number of cases had grown to 131. Of these, about half involved children whose parents rejected vaccination. The 131 cases occurred in seven different outbreaks. There were no deaths, and 15 hospitalizations. Eleven of the cases had received at least one dose of the measles vaccine. Children who were unvaccinated or whose vaccination status was unknown accounted for 122 cases. Some of these were under the age when vaccination is recommended, but in 63 cases, the vaccinations had been refused for religious or philosophical reasons.

On May 24, 2011 the Centers for Disease Control and Prevention
Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention are a United States federal agency under the Department of Health and Human Services headquartered in Druid Hills, unincorporated DeKalb County, Georgia, in Greater Atlanta...

 reported that the United States has had 118 measles cases so far this year. The 118 cases were reported by 23 states and New York City between Jan 1 and May 20. Of the 118 cases, 105 (89%) were associated with cases abroad and 105 (89%) of the 118 patients had not been vaccinated.

On September 29, 2011 Ecuador's Ministry of Health reported an outbreak with 42 cases of measles recorded inside a few adjacent communities of the central Andean province of Tungurahua. No fatalities had been reported as of that date. According to the Ecuadorean government, the viral strain responsible seemed to be linked to African outbreaks; the government also announced that it was launching a massive vaccination campaign to prevent further spreading of the disease.

See also

  • Infectious disease
    Infectious disease
    Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...

  • List of epidemics
  • MMR vaccine controversy
    MMR vaccine controversy
    The MMR vaccine controversy was a case of scientific misconduct which triggered a health scare. It followed the publication in 1998 of a paper in the medical journal The Lancet which presented apparent evidence that autism spectrum disorders could be caused by the MMR vaccine, an immunization...

  • Roseola
    Roseola
    Exanthema subitum , also referred to as roseola infantum , sixth disease and baby measles, or three-day fever, is a disease of children, generally under two years old, although it has been known to occur in eighteen year olds, whose manifestations...

     (baby measles)

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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