The measles (equally called 1RE disease) is a sharp eruptive infection. She attains essentially the children from the age of 5-6 months, and she is definitively immunizing. The name of the first disease originates on account of the fact that to the era where one wanted to establish a disease list provoking an infantile exanthème, she was the first one to be enumerated.
The measles virus
The measles virus is a Morbillivirus of the family of the Paramyxoviridae. It belongs to the same family that the virus of the oreillons. This is a virus that contains RNA and of which the unique reservoir is the sick man. This virus quickly is inactivated by the heat (30 minutes to 56 °C) or the light. It is equally resistant to the antibiotics and sensitive to many disinfecting (the ethanol to 70% for example).
The measles virus transmits itself by the cough droplets in suspension in the air. It can equally propagate itself by direct contact with the secretions of the nose or throat of infected persons. The virus thus éjecté remains dangerous during at least 30 min. It survives little time on the objects and the surfaces.
The period of propagation of the virus begins 2 to 4 days before the appearance of the skin eruption. The virus installation in the organism is done during the incubation period. She continues next during the invasion period. The transmission risk is slight from the second following day it appearance of the eruption.
Symptoms and disease evolution
The measles characterizes itself by 4 phases.
The first phase corresponds to a silent incubation of 10 days after the contagion.
The second phase is called the invasion. She lasts about 4 days during which these the various present child symptoms. It then is attained of a strong fever, his nose flows, it coughs, has the red indeed crying eyes, and can be very fretful. The abdominal pains, the diarrhea as well as the vomitings do so left of the symptoms. During the invasion, the subject is contagious and the sign of Köplick appears. This sign of Köplick is disease pathognomonique, c'est-à-dire that it defines to him only the diagnosis clinic of the measles. It consists in the apparition on the oral muqueuse, to the molar height, of small red irregular tasks with a small central white point. This sign is rare and fugace, often present less than 24 hours.
The third phase of the disease is the eruption. She lasts in average 4 to 5 days, and also is called the phase of state of the measles. The eruption is characteristic of the measles, and consists in the progressive apparition of small red plates more or less in relief, of some millimeters of diameter that confluence in wide beaches but always leaving between they of the intervals of healthy skin. To the first day of this phase, the eruption begins on the face, behind the ears, then spreads itself progressively. Then to the 2nd day, she attains the whole face, the neck, and the superior party of the thorax. To the 3rd day, the trunk and the superior members are attained. The inferior members will be touched the 4th day. Itches are frequent. The fever remains student, then lessens little by little.
During the fourth one and last phase, the skin eruption leaves before to obliterate itself, a brown coloring pulling on the copper, and does places to a visible fine desquamation some days. The fever disappears, but the convalescence will last again about ten days during which the child will cough and again will be tired.
In a general way, the appearance of the spots of Köplick and the characteristic progression of the eruption of the head to the feet suffices to confirm the diagnosis. Nevertheless, when doubts persist, the method of immunofluorescence allows making obvious or not the presence of the likely virus to develop in the cells of the pharynx or the one contained in the urines after culture.
The measles can be confused with the German Measles, the scarlatine, the infantile roséole, the infectious mononucléose or again an eruption of medicinal origin.
The forms more harsh of the measles appear with the young child suffering from malnutrition, especially in case of insufficient provisions in vitamins HAS or in case of immune associated deficit, such the Aids. Of fact, the child does not die directly of the measles but of its complications, such encephalitis, harsh diarrheas or pneumonias.
The measles complications can be of 4 orders: respiratory, neurological, liqueur and eyepiece. One of the neurological complications is the encephalitis post-éruptive or post-infectieuse. She is the most frequented one and arises 3 to 10 days after the eruption. She is not had to a virus multiplication in the brain, but she probably is explained by a car mechanism immun. A car mechanism immun appears when the antibodies attack our own living fabrics. One visible a case for 1 000 measles and his mortality is of 10%. This is not therefore a rarity. She is responsible of a death for 10 000 cases of measles.
Vaccination in the world
In 2005, vaccination concerns close to 77% of the world-wide population, inducing an again increased reduction of the mortality — less than 345 000 deaths that year on 20 millions of patients. The half of the fatal cases being situated in Asia of the Southeast, place where the vaccinal cover is moindre.
Between 2000 and 2005, more than 300 million children of age nine months to fifteen years were vaccinated or revaccinated (in case of failure of the first vaccination). Politics of vaccination systematic of mass could be improved thanks to set it up of system of storage refrigerated for the vaccines and to the creation of a maillage of health centers. In tropical Africa and in equatorial Africa, it was thus observed a decrease closely of three quarters of the deaths passing of 506 000 to 126 000.
The objective of the WHO and Unicef, for 2010, is to reduce the mortality to the world-wide ladder of 90% in comparison with the year figures 2000.
Vaccination in France
Vaccination is the better current preventive treatment. In the measles case, she is done using the lessened virus of which virulence is diminished by biochemical operations.
In terms of prevention, a vaccination carries out itself at the age of 1 year (first injection), then a reminder at the age of 2 years (second injection), in the developed nations. The vaccine often is managed in association with two other vaccines. This one calls a vaccine trivalent.
In France in 2003, 86% of the children of 2 years were vaccinated. This rate is insufficient to eliminate the territory measles, but it is difficult to increase it. In fact, certain persons refuse to let their children vaccinate for several reasons. They believe sometimes that the vaccine induces a fleeting decrease of the immune defenses of the child, the return then more vulnerable to other diseases. Of others dread that vaccination would induce a production of limited antibody in the time, which could induce the appearance of the disease to ages where she is harsher and more serious (with the adult or the nourrisson if the mother not more is immunized). In reality, two vaccinal injections spaced to the minimum of a month as early as the age of a year obtain an immunity to life. A medical study had suspected the vaccine of the measles to be at the origin of certain cases of autism. That has at just created title the debate. Nevertheless of other studies then followed and were able to exclude such a complication. They showed that the autism is not more frequent with the vaccinated children than the vaccinated nos. Indeed, the autism is a pathology presents since the birth, that becomes usually apparent to the age 15-18 months, age to which one the first vaccines for the measles are carried out.
But these arguments oppose themselves to those in favor of a massive vaccination of the children. According to the WHO, vaccination is without danger. With the big world-wide currently vaccinated population since many years, one disposes currently of sufficiently of decline for well connaitre the profits and complications of this vaccine. If all the children are vaccinated, the disease will disappear from itself. It will not have therefore more of risk for the others classify age. At last, the principal argument in vaccination favor is that she allows the child to avoid the disease and therefore its eventual complications that can be very dangerous.
Vaccination presents therefore a good report profit/risk since she allows protecting itself against the disease without health hazard. Of more, in France the vaccine is reimbursed until the age of 13 years.
Often perceived as a benign disease in the developed nations, the measles is in fact a disease very engraves: in 1999, 873 000 persons are dead of this disease and 345 000 in 2005, essentially in the developing country. In these countries, the mortality very student, immediate (1 death on 10 cases in African rural zone) or delayed (by secondary worsening of the malnutrition). The infirmities are numerous, blindness (following keratitises) adding to the encephalopathies.
Before the vaccination arrival at first of the years 1960, the measles was the first world-wide cause of mortality by infection (135 millions of annual cases inducing 6 millions of deaths). The mortality was divided some by 3 at the end of the years 80, close to 10 years after a politics of vaccination of mass. There remains nevertheless again very numerous case of measles because of a not optimum vaccinal cover but also because of vaccination failure in near of 15% of the cas.
In epidemic Europe held sway in 1840, 1860 and 1880. In 1998, the World Health Organization set up for objective of here 2007 the elimination of the measles in Europe. In fact, the measles incidence in France was again of 18 000 cases in 1998 duty probably to the insufficiency of the rate of vaccinal cover. The supervision of the evolution of the incidence in France is carried out by the network Sentineies of the Inserm.
Read also Vaccination