Blackpox, commonly referred to as smallpox in modern terms, is a highly contagious viral infection that affects only humans. Symptoms of this disease are manifested by general intoxication of the body, accompanied by characteristic rashes on the skin and mucous membranes.
People who have had this infection have partial or complete loss of vision and the presence of scars formed at the site of ulcers. In the article we will talk about the types of smallpox, symptoms and treatment methods.
General information and types of disease
Smallpox only infects humans. The development of smallpox is preceded by two types of specific viruses entering the human body:
- Variola major - mortality occurs in forty percent of cases;
- Variola minor - The case fatality rate varies from one to three percent of cases.
There are two forms of the disease:
- typical - has three degrees of severity of varying intensity;
- atypical - has non-standard symptoms and four varieties.
Varieties of atypical smallpox in humans:
- rudimentary smallpox - a disease with an asymptomatic or mild course (no rashes or fever, less often a mild manifestation);
- visceral smallpox is an infectious process that affects internal organs (kidneys, liver, lung system, pancreas, and others) and affects mainly premature babies;
- hemorrhagic smallpox - rashes contain blood particles, hematomas appear on the surface of the skin (a consequence of taking certain medications);
- gangrenous smallpox is a rare, severe pathology with a large rash that forms deep ulcers and is difficult to treat.
These types of chickenpox are quite rare. Complications caused by this disease are expressed in encephalitis and meningoencephalitis, sepsis, keratitis, pneumonia, iritis and panophthalmitis.
What a rash happens
The course of the disease is accompanied by intoxication and characteristic rashes, manifested in several stages, replacing each other.
Chickenpox is characterized by the following types of rash:
- spots - their occurrence is caused by local capillary expansion from the action of the virus, they are pink spots up to four millimeters in diameter;
- papules –appear after a few hours at the spots as a result of serous edema, have the appearance of slightly raised reddish formations resembling insect bites in appearance;
- bubbles - the formation of papules in place is caused by exfoliation of the epidermis - single-chamber bubbles with a clear liquid are surrounded by a red "rim", the contents become cloudy over time;
- pustules - appear at the site of burst bubbles, quickly crust over;
- crusts - the skin heals, the crusts fall off within two to three weeks;
- scars - formed at the site of healed rashes.
At any stage of the disease, it is forbidden to rip off or comb the formations, this can lead to bacterial infection and the formation of long-term non-healing wounds. Also, when washing, do not use sponges or washcloths; for hygiene procedures, it is enough to use a liquid detergent.
The causative agent of smallpox and the incubation period
The cause of the symptoms of smallpox is infection with the virus of this disease from an already sick person or a hidden carrier of the infection.
The causative agent of smallpox is a filterable virus antigenically related to group A erythrocytes. This explains the sharp decline in immunity, high susceptibility to disease and mortality.
A feature of this pathogen is resistance to environmental influences:
- For a long time (from one to many months) the culpritdisease is freely preserved in exfoliated crusts with pockmarks on the surface of the skin of a sick person. If the virus is frozen or lyophilized (freeze and dry), it can remain viable for several years.
- Heating up to 60 °C causes the death of the virus within half an hour, and when the ambient temperature rises to 70-100 °C, the death of the pathogen occurs in a maximum of 5 minutes.
- Under the action of ultraviolet radiation, the death of the virus occurs after six hours.
- Hydrochloric acid, alcohol, ether or acetone will destroy the pathogen in half an hour.
The incubation period of smallpox lasts an average of eight to fourteen days, sometimes it can last up to twenty-five days. A sick person is considered contagious a couple of days before the onset of the first symptoms and until the rash continues.
Contagious disease
Isolation of the pathogen occurs when the surface of the bubbles that appear on the skin again, as well as those that have already dried up, burst open.
In addition, the virus is found in the feces, urine and mouth of the patient.
From here it is clear that the transmission of the pathogen from a sick person to a he althy person occurs through close contact, airborne droplets and from carriers of this virus (humans or animals).
The virus can survive on clothes and bedding.
It should be said that the corpses of dead people from dangerous types of smallpox in humans also carry a high risk of contagion.
The most dangerous for others is the course of the disease, which occurs asymptomatically in a latent form - it is difficult to diagnose and, therefore, isolate the patient in time.
Features of infection
Sick with this disease people at any age, but the most susceptible age category are children under four years of age. Moreover, in childhood, the disease is easily tolerated, and the body acquires strong immunity.
Adults suffer from severe intoxication, severe chickenpox and the possible consequences for them can be the most dangerous. The action of the virus affects the lymph nodes, which become painful and tense and increase in size several times. Meningitis, pneumonia, visual impairment may also develop. The latter is due to the fact that ulcers affect the cornea of the eye.
Infection with a virus from a sick person occurs two or three days before the first signs of the disease appear - rashes. The first manifestations of the disease occur quickly and acutely, a person feels unwell a few days before the active phase of the virus begins.
The process of infection is as follows:
- The inhaled contaminated air enters the respiratory tract and then moves to the lymph nodes, and then enters the blood, spreading throughout the body.
- The epithelium is infected in a hematogenous way, in which the virus then begins to multiply intensively, causing a person to develop rashes on the mucous membranes and skin and reduce immunity (types of chickenpox rashes depend on itsvarieties).
- As a result of a decrease in the protective functions of the body, the process of transition of vesicles (cavities with liquid inside) into pustules (cavities with pus) is activated.
- The growth layer in the epidermis dies, a destructive process develops, as a result of which scars form.
- In severe cases, toxic shock and hemorrhagic syndrome (bleeding) may develop at this stage.
Primary symptoms of the disease
With a typical development and course of the disease, symptoms can be noticed after eight to fourteen (usually twelve) days from the moment of infection. Depending on the type of smallpox, the symptoms may be more or less severe.
Primary symptoms of infection are:
- high temperature (37.5°C to 41°C);
- chill;
- acute lower back pain;
- pain in the limbs and sacrum;
- intense thirst;
- dizziness;
- vomit;
- headache.
Course of the disease in the first phase
After the onset of the first symptoms, on the second or fourth day of high fever, patients develop an initial rash on the skin - initial formations that are not yet classified as typical smallpox.
The appearance of the chickenpox rash at the initial stage is hyperemic skin, similar to roseolous, morbilliform or erythematous lesions.
It can also be localized in the armpits,chest, abdomen and on the inside of the thighs in the form of a hemorrhagic rash. In this case, the lesion has small multiple hemorrhages in the thickness of the skin and mucous membranes. Ecchymosis may develop - large spots more than three millimeters in diameter with hemorrhages. A photo of a person with smallpox and how the symptoms and pockmarks on the face look can be seen in this article.
Duration of presence in a typical form of the disease, a spotted rash is several hours, and a hemorrhagic rash is a little longer.
Middle phase disease
The middle phase of the manifestation of smallpox is characterized by the fact that by the fourth day the temperature drops noticeably in patients, symptoms and intoxication decrease, the general condition improves slightly.
At the same time, characteristic rashes begin to appear on the scalp and face (the type of rash with chickenpox depends on the type of disease), further spreading to the limbs and torso, soles and palms.
In parallel, pockmarks that have arisen earlier go through successive stages of transformation according to the following scheme: spot - papule - vesicle - pustule - crust - scar.
Skin rashes with smallpox are characterized by a certain density, in the center of the papule there is a depression from which the infiltrate seeps out. In addition to the previously mentioned areas, rashes can also be localized on the mucous membrane, affecting the nose, larynx and oropharynx, trachea and bronchi.
With the further spread of the virus, the infection passes to the conjunctiva of the eyes,urethra, rectum and female reproductive organs. Further, erosions form on the mucous membranes.
The final stage of the disease
The eighth-ninth day of illness is characterized by suppuration of the blisters. This process worsens the patient's condition again. In addition, symptoms of toxic encephalopathy join at this stage.
Outwardly, this is expressed in a violation of consciousness, the occurrence of delirium and an excited state, convulsions appear in children.
The duration of the phase of drying and falling off of the crusts is one to two weeks. By the end of the process, characteristic scars appear on the scalp, as well as on the face.
Severe disease can lead to death. Severe and dangerous types of smallpox include pustular-hemorrhagic and confluent forms of the disease, as well as smallpox purpura.
Diagnosis and treatment features
The primary task of diagnosing chickenpox is to take into account the clinical manifestations characteristic of the virus, which are then used for clinical studies, to which they add another swab from the oral cavity and a blood test. Then, based on the analysis performed using electron microscopy, PCR and microprecipitation, the type and degree of the disease is diagnosed.
The initial result is obtained within a day, and then the virus is isolated and identified - it is important to quickly analyze the causes, signs and symptoms of smallpox.
Treatment of smallpox is based on taking the followingdrugs:
- antiviral, for example, "Metisazon" course up to a week twice a day for 0.6 g;
- anti-smallpox immunoglobulin intramuscularly at a dosage of three to six milliliters.
It is worth noting that the therapeutic efficacy of these drugs is rather weak, but so far no other drugs for etiotropic treatment have been created.
To relieve concomitant symptoms and prevent the onset of a bacterial infection, antiseptic drugs and antibiotics (macrolides, semi-synthetic penicillins, cephalosporins) are prescribed.
To detoxify the body, crystalloid and colloid solutions, plasmaphoresis and ultrafiltration are used. If itching occurs, the skin is treated with alcohol or vinegar.
As for the prognosis, it is determined based on the type of smallpox and the course of the disease, as well as how the patient tolerates it.
Lethal outcome is predicted in the range of two to one hundred percent. A favorable ending to the disease is most likely for vaccinated patients.
At the first suspicion of infection with the smallpox virus, you should immediately contact the infectious disease specialist.
Disease prevention
Since smallpox is a dangerous disease, not only treatment is important. Preventing smallpox symptoms is key to defeating this virus.
Vaccination is the main preventive measure. It does not protect against the penetration of the virus, but greatly alleviates the symptoms of the course of the disease. Vaccinationproduced by variolation - using an early vaccine, which is not safe.
Susceptibility to the pathogen is most relevant for those people who have not been vaccinated, since natural protection against chickenpox does not develop. The type of immunity obtained by receiving the varicella vaccine is called acquired immunity.
Thanks to universal and mandatory vaccination in the middle of the last century, the spread of this virus was defeated. The World He alth Organization announced in 1980 that smallpox was officially eradicated from the entire planet.
Despite this, people suspected of being infected with this virus must be isolated, because the disease cannot be completely ruled out - strains of this infection are stored in two US laboratories. The question of their destruction remains unresolved.
