Measles belong to sharp viral infectious diseases, are characterized by a combination of catarrhal symptomatology to specific ekzantemy. The virus of measles gets into an organism in the airborne way. The incubatory period lasts up to 2 weeks, sometimes up to 1 month. The catarrhal period of measles is shown by cough, fever, cervical lymphadenitis. It is succeeded by the period of rashes with landmark emergence of elements of rash, characteristic of measles. Recovery begins 1-2 weeks later from the beginning of measles. Diagnosis of measles is performed, as a rule, on the basis of clinical data. Treatment is mainly symptomatic, it is directed to decrease in body temperature, desintoxication, increase in resilience of an organism.
Measles belong to sharp viral infectious diseases, are characterized by a combination of catarrhal symptomatology to specific ekzantemy.
Characteristic of the activator
The RNA-containing measles virus, belongs to the sort Morbillivirus. In the external environment it is unstable, it is inactivated during the drying, impact of a sunlight, ultra-violet radiation, when heating to 50 °C. The virus is capable to remain in room temperature 1-2 days, when cooling (a temperature optimum for viability preservation: from-15 to -20 °C) there are active several weeks.
The tank and source of an infection is the sick person. Allocation of an infection begins in the last 1-2 days of an incubation, all prodromalny period and continues for 4 days of the period of rashes. In certain cases time of contageousness drags on up to 10 days from emergence of an ekzantema. The asymptomatic carriage of measles is not noted.
The virus of measles is transmitted on the aerosol mechanism in the airborne way. The patient allocates the activator to the environment during cough, sneezing, just at exhalation of air and a conversation. The fine suspension is carried with air current on the room. In view of weak stability of a virus the contact and household way of transfer is excluded. At infection with measles of the pregnant woman transplacentary transmission of infection is possible.
People are extremely susceptible to measles, after transferring lifelong intense immunity remains. Usually the disease arises at children's age, measles occur at adults seldom and proceed much heavier. The peak of incidence falls on the winter and spring period, the minimum quantity of cases is registered in August-September. Incidence of measles considerably decreased in view of performing planned vaccination of the population recently.
Pathogenesis of measles
The virus takes root into an organism through a mucous membrane of the top airways, is replicated in cages of their integumentary epithelium and extends on an organism with blood current, collecting in structures of reticuloendothelial system. The virus of measles has a tropnost to integumentary fabrics (skin, a conjunctiva, mucous membranes of a mouth and airways).
Defeat by a brain virus with development of clumsy encephalitis is in rare instances possible. The epithelium of mucous respiratory system affected with a virus sometimes is exposed to a necrosis, opening access for a bacterial infection. There is an opinion that the causative agent of measles is capable is long to remain in an organism, causing the slow infection leading to developing of system diseases (a sklerodermiya, a system red volchanka, multiple sclerosis, etc.).
The incubatory period of measles proceeds 1-2 weeks, in cases of introduction of immunoglobulin is extended up to 3-4 weeks. The typical course of measles happens to consecutive change of three stages: catarrhal, rashes and convalescence. The catarrhal period begins with rise in temperature and development of symptoms of the general intoxication. Fever can reach extremely high figures, patients complain of an intensive headache, sleeplessness, a fever, the expressed weakness. At children the symptomatology of intoxication is substantially maleficiated.
Against the background of an intoksikatsionny syndrome in the very first days there is dry cough, conjunctivitis (the century is followed by intensive hypostasis) with purulent separated, a photophobia is noted mucopurulent . At children pharynx hyperaemia, granularity of a back wall of a throat, a face bloated is expressed. At adults catarrhal signs are more weakly expressed, but regionarny lymphadenitis can take place (generally cervical lymph nodes are surprised). Auskultation of lungs notes rigid breath and dry rattles. Sometimes the disease is followed by ease of intestinal activity, dispepsichesky symptoms (nausea, vomiting, heartburn, an eructation).
The first feverish wave usually makes 3-5 days then body temperature decreases. Next day again there is a rise in temperature and aggravation of intoxication and the catarrhal phenomena, and on a mucous membrane of cheeks spots of Filatova-Koplika-Velskogo – a specific clinical symptom of measles are noted. Spots settle down on the internal surface of cheeks opposite to small molars (sometimes passing on mucous gums), represent the white sites which are a little raised over a surface surrounded with a thin strip hyperemic mucous (a type of "semolina porridge"). As a rule, at emergence of rash these spots disappear, at adults can remain during the first days of the period of rashes. At the same time or a little earlier, than spots of Filatova-Koplika-Velskogo, on soft and, partially, hard palate there is an enantema representing red spots about a pin head of irregular shape. 1-2 days later they merge and cease to be allocated against the background of the general hyperaemia mucous.
The general duration of the catarrhal period makes 3-5 days at children and about a week at adults. Then there comes the rash period. Rash at measles is originally formed on a hairy part of the head and behind ears, extends to a face and a neck. By second day of a rash cover a trunk and shoulders. On third day rash covers extremities and begins to turn pale on a face. Such sequence of rashes is characteristic of measles, is a sign, significant for differential diagnostics.
Clumsy rash represents the bright spotty and papular ekzantema inclined to formation of drain figured groups with intervals of not changed integuments. Rash at adults is more expressed, than at children, at a heavy current can gain hemorrhagic character. In the period of rashes the catarrhal symptomatology amplifies and fever and intoxication is aggravated.
The period of a convalescence comes 7-10 days later after the beginning of a disease (adults have measles duration more), the clinical symptomatology abates, body temperature is normalized, elements of rash regress (similar to an emergence order), leaving behind the light brown sites of the increased pigmentation disappearing 5-7 days later. On the place of pigmentation some time remains an otrubevidny peeling (in particular on a face). In the period of a convalescence decrease in immune factors of protection of an organism takes place.
Mitigirovanny measles represent the atypical clinical form of an infection which is found at passively either actively immunizirovanny persons, or earlier had measles. Differs in more long incubatory period, the ill-defined or absent symptomatology of intoxication and the shortened period of catarrhal manifestations. It is noted typical for measles of an ekzantem, but to rashes the sequences can appear on all parts of the body or in the return at once (going back from extremities to the person). Often spots of Filatova-Koplika-Velskogo do not come to light.
One more atypical form are abortive measles – the beginning its same, as well as in everyday occurences, but 1-2 days later the symptomatology abates, rash extends on a face and a trunk then regresses. Fever at an abortive form usually takes place only in the first day of rashes. Sometimes by means of serological techniques subclinical forms of measles come to light.
Measles most often are complicated by secondary bacterial pneumonia. Children of early age have arising inflammations of a throat (laryngitis) and bronchial tubes (bronchitis) is led sometimes to development of the false croup menacing with asphyxia. Stomatitises are sometimes noted.
At adults measles can promote development of meningitis and meningoentsefalit, and also polyneuritis. Rare, but quite dangerous complication – clumsy encephalitis. Now the theory of development of autoimmune diseases according to which, the virus of measles can take part in pathogenesis of these states takes place.
Diagnosis of measles
Diagnosing of measles is successfully carried out on the basis of clinical manifestations. The general blood test shows a picture, characteristic of a viral infection: against the background of a moderate leykopeniya (or concentration of cells of white blood remains within norm), , the raised SOE. At adults can note the lowered concentration of neutrophils and lymphocytes and lack of eosinophils.
Results of specific bacteriological and serological researches (seldom applicable in clinical practice) have retrospective character. At suspicion on development of pneumonia the X-ray analysis of lungs is required. At development of neurologic complications consultation of the neurologist, a rheoencephalography, brain EEG is shown to the patient with measles. For diagnosis of meningitis the lyumbalny puncture can be shown.
Treatment of measles
Measles treat on an outpatient basis, hospitalize patients with the heavy complicated current, or according to epidemiological indications. The bed rest is appointed to all feverish period. Rather effective etiotropny therapy it is not developed now, treatment consists in simplification of symptomatology and the prevention of complications. As the measure reducing toxicosis recommend plentiful drink. Intensive dezintoksikatsionny actions are made in cases of extremely heavy current.
Patients need to observe hygiene of a mouth and eyes, to avoid bright light. As pathogenetic and symptomatic therapy appoint antihistaminic, febrifuges, vitamins and adaptogens. In early terms of a disease interferon reception considerably improves a current. In case of threat of developing of a secondary infection, appoint antibiotics of a broad spectrum of activity. Korevy encephalitis demands purpose of high doses of Prednisolonum and other measures of intensive therapy.
Forecast and prevention of measles
Neoslozhnenno the proceeding measles usually comes to an end with an absolute recovery, there is no cosmetic defect left after rashes. Adverse the forecast can become in case of developing of clumsy encephalitis.
Specific prevention of measles consists in planned vaccination of the population LCV (live clumsy vaccine). The first vaccination against measles is made to children in 12-15 months, the revaccination is carried out in 6 years. Isolation of patients continues up to 10 days, restriction of contact with not imparted and not being ill children - up to 21 days since the beginning of a disease.