Tick rickettsiosis: treatment, causes, symptoms

Infectious diseases - a group of pathological conditions, which are highly contagious. Similar ailments cause certain bacteria and viruses. All infections have common characteristics. They include: epidemiology, transmission routes and clinical manifestations. One of the infectious diseases is tick-born rickettsiosis. There are several varieties of this pathology. Combine all rickettsiosis such signs as fever, intoxication syndrome, primary skin affect and vascular lesions. The main way of transmission of these diseases is transmissible. That is, through the bites of insects, distributed in specific climatic conditions.

Description of tick rickettsiosis

Tick rickettsiosis is an infectious pathology characterized by cutaneous manifestations, widespread vasculitis and intoxication syndrome. The disease differs by transmissible transmission. The infection is transmitted by mites and lice. There are several variants of the flow of rickettsiosis. The main difference between these pathologies is the type of pathogen. Some rickettsiosis are common in the steppe and desert areas, others in the tropical climate. Nevertheless, all these pathologies have a similar clinical picture. It is possible to suspect the disease by characteristic symptoms, as well as due to epidemiological characteristics. The main method of diagnosis is a serological study, which allows you to accurately determine the type of pathogen.

What are rickettsiosis?

As is known, rickettsiosis is a large group of diseases. They are distributed all over the world. The most common types are:

1. Rickettsia prowazekii - this causative agent causes typhus. This disease is transmitted by a transmissible route (through lice bites).
2. Rickettsia typhi is the causative agent of endemic typhus. It is transmitted by the bites of rodents and fleas.
3. Rickettsia sibirica. This causative agent causes the disease of North Asian tick-borne rickettsiosis.
4. Rickettsia burneti. With the penetration of this pathogen into the human body develops Ku fever. The disease is transmitted by transmigration - through the bites of ixodid ticks.
5. Rickettsia orientalis. Like the previous varieties of rickettsiosis, this pathology is transmitted by tick bites.

In addition to these diseases, there are many other infections caused by different strains of this pathogen.

Epidemiological characteristics of rickettsiosis

Rickettsiosis differ among themselves not only by the nature of the pathogen, but also by epidemiological characteristics. Despite the widespread prevalence in the world, every disease is prevalent in a certain area. For example, epidemic typhus also calls prison or ship fever, since this pathology is transmitted through the bites of lice, which were widespread among prisoners and seafarers. A similar disease, but caused by the causative agent Rickettsia typhi, is more often recorded in regions with a warm climate. Especially often it occurs in rural areas in the summer.

Tick rickettsiosis is common in the habitats of these insects. This group of infectious pathologies is found in North Asia, Japan, Australia, mountainous areas. Most rickettsiosis are zoonotic diseases. Intermediate reservoir of infection is considered wild and domestic animals, rodents. The carriers of rickettsiosis are various kinds of ticks. Since these insects reproduce in the summer (May-September), during this period the incidence sharply increases. Most often, the infection affects people working on the street (cottages, gardens, pastures) and in contact with animals.

The cause of rickettsiosis

The etiologic factor of the onset of the disease is a microorganism - rickettsia. This infectious agent can be attributed to bacteria or viruses. This phenomenon is explained by the fact that, despite the structure of the microorganism (rods or cocci), rickettsia has the capacity for intracellular parasitization. The causative agent is unstable in the environment. Rickettsia perishes under the influence of high temperatures or means for disinfection. Nevertheless, they can remain viable for a long time in a cold and arid climate. In addition to the transmission pathway, rickettsia can enter the body through blood transfusions, from the mother during childbirth. For some diseases of this group, there are other ways of infection. Among them - alimentary and airborne infection. Factors provoking tick-borne rickettsiosis include:

1. Contact with rural pets, dogs.
2. Non-compliance with personal hygiene.
3. Contact with infected people and carriers of pathology.

Mechanism of disease development

The disease develops a few days after the introduction of the tick into the skin. The duration of the incubation period depends on the type of pathogen and the immune response of the organism. When a tick bites , a local reaction arises. The skin becomes edematous, hyperemic, morbidity is noted. Infiltration occurs due to the accumulation of cells of the immune system at the site of the insect. From there, pathogens - rickettsia - penetrate into the lymphatic vessels and nodes. There they temporarily settle and multiply. Considering the fact that the lymph nodes belong to the organs of the immune system, they increase noticeably. Activation and proliferation of cells for the control of bacterial agents takes place. Later rickettsii enter the blood vessels. There is bacteremia and toxemia. First of all, the veins and arteries of the skin are affected. In the walls of the vessels an inflammatory reaction develops, leading to destructive changes in the endothelium. In addition, rickettsia often enter the arteries and veins of the brain. As a result, signs of central nervous system damage, meningitis and encephalitis develop, possibly acute circulatory disturbance. The mechanism of infection development causes a clinical picture of the pathology of tick-borne rickettsiosis. ICD-10 is an international classification, which includes all diseases. Not an exception and this infection. In addition, complications of pathology, such as meningitis, encephalitis and vascular damage, are coded in the ICD-10 separately. The main disease has the code A77.

Tick rickettsiosis: symptoms of pathology

Despite the fact that tick-borne rickettsiosis differ among themselves, they all have common clinical manifestations. The duration of the incubation period is on average 3 to 7 days. Often penetration of ticks into the skin remains unnoticed at the onset of the disease. Sometimes there is noticeable infiltration and regional lymphadenitis. Primary affect is characterized by densification, in the center of which there is necrosis of the skin (brown color), and on the periphery - hyperemia (red corolla). After 2-3 days, an intoxication syndrome and a fever of a permanent nature are added. The patient complains of body aches, fever to 39 degrees, muscle pain, general weakness. The febrile period is about 1-2 weeks. In addition to symptoms of intoxication, at the beginning of the disease appear rashes. They have a rose-leafy-papular character. First the rash arises on the limbs, later spreads to the trunk. The skin background does not change. These signs are characterized by tick-borne rickettsiosis. Photos of skin manifestations can be found in the specialized literature. Distinguishing rashes between each other is very important for the diagnosis of infectious pathologies.

Identification of tick rickettsiosis

It is impossible to be based only on a clinical picture in order to reveal tick-borne rickettsiosis. Diagnosis of the disease should include laboratory research. After all, the symptoms of pathology can resemble many other infections. To make an accurate diagnosis indicating the type of pathogen, serological tests are performed . Among them - enzyme immunoassay, complement fixation, hemagglutination, etc. Microscopy of blood, liquor, urine and separable infiltrate is also carried out.

Tick rickettsiosis: treatment of infection

Since the disease refers to bacterial infections, antibiotics are necessary for treatment. To this end, use drugs "Tetracycline" and "Levomycetin", as well as their analogues. In case of severe disease, the patient should be hospitalized in an infectious hospital. For the purpose of detoxification, a solution of 5% glucose with ascorbic acid is injected intravenously. With bradycardia, it is necessary to use vasopressor drugs. They include medicines "Atropin", "Caffeine". Symptomatic therapy is also used - antipyretic, antihistamines. Ticks are removed using tweezers. With the development of complications, specific treatment is carried out.

Consequences of tick-borne rickettsiosis

It is important to start treatment of tick-borne rickettsial disease as soon as possible. The consequences of infection can be severe. When untimely referral to the doctor, complications develop from the nervous, respiratory and cardiovascular system. Among them - pneumonia, bronchitis, meningitis and encephalitis, myocarditis, etc. In severe cases, an infectious-toxic shock develops.

Prevention of tick-borne rickettsiosis

Nonspecific prevention includes the control of insects and rodents, as well as compliance with personal hygiene. Against typhus and Ku fever vaccination is carried out. If a disease is detected, it is necessary to sanitize the premises, and also to examine all persons who were in contact with the patient. If the mite has already penetrated into the skin, but the symptoms of infection have not developed, emergency medication is being performed. Antibiotics "Doxycycline" and "Azithromycin" are used.