Smallpox: Symptoms and Treatment
Smallpox (or smallpox, as it was called earlier) is a highly infectious viral infection that affects only people. Smallpox, the symptoms of which are manifested in the form of general intoxication combined with characteristic rashes covering the skin and mucous membranes, is completed for patients who have suffered, partial or complete loss of vision and, in almost all cases, scars left after ulcers.
Two kinds of specific viruses provoke the development of smallpox, Variola major and Variola minor. The first of these viruses determines mortality rates in the range of 20-40% (based on some data this figure is about 90%), the second — within 1-3%.
Typical cases of smallpox, as already noted, occur in combination with intoxication and a characteristic type of eruptions, centered on the mucous membranes and on the skin. These eruptions, in turn, manifest themselves in the form of several stages with their alternate transformation first into the spots, then into the vesicles, then into the pustules, then into the crusts and finally into the scars.
We also noted that only people become infected with smallpox (within the framework of experiments with attempts to infect animals, any results in this direction are achieved with difficulty). As a causative agent of smallpox, a filtering virus that is antigenically related to erythrocytes in group A acts as a result of which weak immunity is associated with a simultaneous high susceptibility to the disease and the death rate noted for the respective group of individuals.
The peculiarity of the causative agent of smallpox is also that it is very stable in relation to the influence of environmental factors, especially the conditions with a lowered temperature and with drying. Over a long period of time (calculated in many months), the causative agent of the disease can be freely preserved in scales and in crusts removed from pockmarks, focused on the skin of a sick person. When freezing or lyophilizing (the way soft drying is performed with pre-freezing), the viability of the virus can reach several years. Meanwhile, the heating of the virus to 60 ° C leads to its death in a period of about half an hour, while heating the same within 70-100 ° C, its death occurs in a period of 1 to 5 minutes. Exposure to ultraviolet radiation results in death of the virus after six hours. When using ether, alcohol, acetone or hydrochloric acid, you can disinfect it in half an hour.
The duration of the incubation period of smallpox (the time period between the moment of entry into the body of the virus and the manifestation of the first symptoms accompanying the disease, this virus is provoked) is on average about 8-14 days, but more often its duration is about 11-12 days. The ill person is contagious for the environment during the entire period of rashes (there is a suggestion that this is actual and a few days before the rash appears), which, accordingly, determines the period of the general period of contagion within three weeks.
Virus isolation occurs through bursting vesicles appearing on the skin, as well as through those vesicles that already begin to dry out on it. In addition, the virus is present in urine, feces and in the oral cavity of a sick person. Accordingly, the transmission of the pathogen occurs through direct contact of the sick person with a healthy, airborne droplet, from animals acting as carriers and from healthy people, also acting as such. The viability of the virus is preserved on bed linens and on clothes. Separately, it should be noted that the corpse of a deceased person from this disease also determines a high degree of infectiousness.
The greatest danger in terms of infection is determined for such a group of patients whose smallpox course occurs in an erased form, because this variant of the disease course complicates the possibility of its diagnosis, due to which it is rather difficult to isolate patients in time.
Susceptibility to infection with the virus is relevant for patients who have not been vaccinated. As for the natural immunity to this disease, it does not exist. Smallpox can be infected at any age, but in particular, children under the age of 4 are particularly vulnerable.
As for the characteristics of infection, the picture is as follows. The inhalation of air contaminated with the virus leads to the fact that it is in the respiratory tract (infection can also be effected by the methods listed earlier). Then the virus gets to the nearest lymph nodes, and then into the blood, which provokes viremia — getting it into the bloodstream and then spreading through the body. The infection of the epithelium occurs in a hematogenous way, and it is here that the smallpox virus begins to multiply intensively, which in turn causes the enanthema and exanthema (rashes on the mucous membranes and the skin) to appear in the infected person.
Because of the concomitant weakening of the immune system, secondary flora is activated with the transformation of vesicles (limited surface cavities with a liquid inside them, slightly elevated above the skin level) into pustules (formations similar to the previous form but containing pus in their cavities). Further, death occurs in the epidermis of the growth layer, as a result of which deep processes of suppuration and destructive character develop, already against the background of this, scar formation occurs.
In addition, the possibility of developing an infectious-toxic shock under the influence of these processes accompanying the course of smallpox is not ruled out. Heavy forms of it occur in combination with the development of hemorrhagic syndrome (bleeding of the skin and mucous membranes).
If the cases of a typical course of the disease are considered, then the symptoms of smallpox in this case appear after 8-12 days from the time of infection (this, respectively, determines its incubation period).
The initial period of the disease is characterized by the appearance of chills and fever. The temperature in patients until the time of suppuration of skin rashes, as a rule, is noted within no more than 37.5 ° C, subsequently its increase can be fixed within the limits of 40-41 ° C.
The patients have severe pain in the lower back of the «tearing» type, the pain appears in the area of the sacrum and extremities. In addition, manifestations of dizziness and severe thirst, vomiting and headache are relevant. In some cases, the course of the initial period of the disease, all symptoms of smallpox are manifested in a mild form.
In the period of the second or fourth day of fever manifestation, an initial skin rash begins to form in the patients (a rash that appears before its variant, which is considered to be typical in smallpox), which can be manifested either as areas of hyperemia (roseosa, Corneal or erythematous rash) or as a hemorrhagic rash that is concentrated on both sides of the chest (from the axillae to the pectoral region), including from the area just below the navel with the capture of the inner Femoral surface and the area of inguinal folds (which, thus, forms the so-called «Triangle of Simon»).
The appearance of hemorrhages is characterized by their similarity to purpura (a rash that does not disappear under pressure on it and has the appearance of small multiple hemorrhage into the mucous membranes and the thickness of the skin), and in some cases with ecchymoses (large spots of 3 mm in diameter, Also having the form of hemorrhages affecting the skin and mucous membranes). The duration of confinement of the spotted rash is of the order of several hours, if the rash is hemorrhagic, the retention time, respectively, is longer.
By the fourth day of the manifestation of smallpox in patients, the temperature decreases and, in general, the symptomatology accompanying its initial period is weakened. At the same time, it is from this time that pockmarks begin to appear that focus on the face and skin of the head, as well as on the extremities and on the trunk. Localization of the rash is also possible in the area of the soles and palms. It already noted and following the scheme of transformation from the spots and to the scar (taking into account the intermediate states of papules, vesicles, pustules and crusts). Skin elements that appear with a smallpox, according to the type of manifestation, are characterized by their own density, in the center of the formation there is a characteristic retraction, the base is subject to infiltration (leakage of fluid from the elements of the rash).
In addition to these zones, the pocklets focus on the mucous membranes, thereby affecting the nasal mucosa, larynx and oropharynx, trachea and bronchi. The conjunctiva of the eyes, the urethra and the female genitalia, the rectum are affected. In the future, these formations on mucous membranes acquire the form of erosion. Varieties of eruptions in smallpox are not observed — all of them with this disease correspond to one common stage. The puncture of the vesicle does not lead to a drop in the smallpox due to its multicameral, formed by the end of the transformation scheme of the elements of the rash, the scars after falling off the crust will have different depths of scars.
By the eighth to ninth days of the course of the disease, suppuration of the blisters occurs, which is accompanied by a repeated worsening of the patients, which is also accompanied by the symptomatology of the toxic form of encephalopathy. In particular, patients are disturbed by consciousness, they rave and are in a state of arousal. Smallpox in children is accompanied at this stage by the appearance of seizures.
The duration of the drying period of crusts and their subsequent falling off is about one to two weeks. The hairy part of the head and face acquire characteristic numerous scars to complete this process. A particularly severe form of the disease can lead to death before the transition to rash.
As a serious form of manifestation of the disease, the draining form of smallpox, the pustular-hemorrhagic form, and the smallpox purpura are considered.
A vaccine against smallpox can help ease the course of this disease. Its main features in this case are a long incubation period (it lasts about 15-17 days). Symptoms of intoxication and general malaise have a moderate character of manifestation. A rash with smallpox (a typical rash) manifests itself in a uninvolved form, in the future it is not accompanied by a stage of pustules formation, the scars do not remain on the skin. In general, in this version of the flow of smallpox, recovery comes two weeks later. In addition, light variants of smallpox forms are possible, in which the fever is manifested for a short time, there is no rash, the state of health disorders are insignificant, as well as variants of the smallpox flow, in which the rash manifests itself uninvolved, with similar feeling of patients.
Encephalitis and meningoencephalitis, sepsis, keratitis, pneumonia, iritis and panophthalmitis are considered as complications that may subsequently manifest themselves against smallpox.
The diagnosis of smallpox involves taking into account the clinical signs characteristic of the disease (in particular, rash), which are used for subsequent clinical trials. So, the diagnosis of the disease is based on the analysis of the contents of the formed skin elements in a particular stage (vesicles, pustules, vesicles, crusts), and also examines the blood and smear of mucus taken from the oral cavity. The presence of smallpox virus in samples taken is determined by micro-precipitation, PCR, electron microscopy. The preliminary result is obtained within 24 hours, due to further, more thorough examination of the samples, the virus is already isolated and its identification is detected.
Treatment of smallpox is based on the use of antiviral drugs (in particular, metisazone, a course of up to 6 days, twice a day at doses of 0.6 g.), As well as an antiplatelet immunoglobulin (intramuscularly, doses from 3 to 6 ml. ). In general, a highly effective drug that could be used in the framework of etiotropic treatment has not been created until now, and the therapeutic efficacy of these drugs is rather low.
As a preventive measure to prevent adherence to the picture of the disease of bacterial infection, which in particular affects the affected areas of the skin, antiseptics are used. Actual bacterial complications require the appointment of patients with antibiotics of a wide spectrum of action, which in particular can act as cephalosporins, semisynthetic penicillins and macrolides. Detoxication of the body is provided through the implementation of measures in the form of crystalloid and colloidal solutions, plasmaphoresis and ultrafiltration (in some cases). When skin itching occurs, the skin can be treated with vinegar or alcohol.
With respect to the prognosis, it can be said that it is determined on the basis of the clinical form of the course of the disease, the general condition of the patient within the premorbid period (this state is considered the initial state of the patient, before the onset of the disease). Cases of lethality are noted in the range of 2-100%. The mild course of the disease determines a favorable prognosis for those patients who have been vaccinated. Reconvalvescents, i.e. Recovered patients are to be discharged from the hospital after they, respectively, have a clinical recovery, but not earlier than forty days after the onset of the disease.
After the transfer of mild forms of the disease, the extract is made without any adjustments to the suitability for military service, while the transfer of severe forms requires a decision on this issue by the VVC, taking into account the corresponding residual phenomena (i.e., phenomena, Relevant after the transfer of the disease, in particular, here we consider changes in vision against smallpox, etc.).
As a preventive measure of the disease under consideration, first of all, variolation (i.e., the method of vaccination using an early and unsafe vaccine) is singled out. It should be noted that smallpox is the first, as well as the only infectious disease, the victory over which was achieved through mass vaccination. However, vaccination against smallpox — a method of prevention, terminated in the USSR in the late 70’s, that is, now vaccinations against smallpox are not necessarily done. In 1980, WHO, in one of its regular sessions, announced that smallpox was officially eliminated on the planet. Meanwhile, the potential danger of smallpox is still being considered, which is explained by the preservation of strains under the conditions of two, allegedly, the main laboratories (USA and Russia). The issue concerning their destruction was earlier postponed until consideration in 2014.
Given the fact that smallpox acts as a particularly dangerous infection, sick people, as well as people with suspected infection, must be isolated, with appropriate clinical examination and treatment in a hospital. For those persons who were in contact with the sick (or with a person who is suspected of the relevance of smallpox), a quarantine is established for a period of 17 days. This also implies the need for vaccination, regardless of whether it was carried out earlier and how much time has passed since then.
If symptoms appear that may indicate the relevance of smallpox, you need to contact an infectious disease specialist.