Brucellosis: what it is, how brucellosis manifests itself in people (photos), causes, symptoms and treatment

General information

Brucellosis is a zoonotic infection, that is, an infection transmitted from animals to humans. This disease is characterized by multiple damage to organs and systems - the genitourinary, vascular, digestive, and reproductive systems may be affected. The disease is caused by bacteria of the genus Brucella .
This infection mainly affects animals and birds. But if people come into contact with animals infected with brucellosis or with animal products containing the infection, they also subsequently become ill. According to Wikipedia, the symptoms of this disease were first described by Hippocrates more than two thousand years ago. But the first scientific description of brucellosis in 1861 was made by a military doctor from England, Marston. After this, the disease was mentioned in written works in different countries, and it received different names - for example, Mediterranean and Maltese fever. It was also called “undulant fever.” The definition of “undulant fever” appeared because of a special symptom of brucellosis - relapsing fever.

In 1886, the microbes that cause this disease were discovered by a scientist from England, David Bruce. It was in honor of the scientist that these bacteria were named Brucella. There is another notable fact in the history of this disease: in the mid-twentieth century in the United States, the bacterium was used as a bacteriological weapon. But in 1969 this was prohibited.

Fresh milk and more. How can you become infected with brucellosis?

Bang and Traum's disease, Bruce's septicemia, Mediterranean, goat, Crimean fever - behind all these intricate terms hides one socially significant infectious and allergic disease - brucellosis. How can one become infected with it, what are the symptoms of this infection, how to treat it? The answers to these and other questions about brucellosis are in our article.

A little history

The first information about brucellosis appeared in the mid-19th century thanks to the English military surgeon J. Marston. He was studying sick soldiers on the island of Malta and noticed that they all drank goat's milk. A little later, in 1887, British Army doctor David Bruce isolated the causative agent of brucellosis from the spleens of five English soldiers who died from fever. It was originally named Micrococcus Maltese and later renamed Brucella in honor of its discoverer.

The connection between the disease and animals was finally established during the research of D. Bruce and other scientists already at the beginning of the 20th century. By this time, three types of Brucella had been identified. Currently, six types of the causative agent of brucellosis are known, four of which are extremely dangerous to humans.

Features of the causative agent of brucellosis

Microorganisms of the genus Brucella are gram-negative bacteria that are resistant to low temperatures, but do not “like” high temperatures at all: when boiled, Brucella dies instantly, and when heated to 60 degrees Celsius, within half an hour. Serious enemies of bacteria are direct sunlight and disinfectants.

Despite their apparent vulnerability, bacteria have qualities that allow them to parasitize the body for a long time, depleting it. One of these qualities is the ability to transform into specific L- and S-forms under the influence of antibiotics and immune cells. This feature leads to chronicity of the process with subsequent development of complications.

Brucella secretes substances that inhibit the activity of macrophages (defender cells that are involved in the capture and destruction of pathogenic microorganisms). This creates conditions for Brucella to parasitize inside the cells of the immune system. Endotoxin, released during the death and destruction of these bacteria, causes severe intoxication of the body and leads to metabolic disorders in it.

How do you get infected with brucellosis?

The main spreaders of brucellosis are goats, sheep, pigs, and cows, although all types of domestic animals and birds are susceptible to the disease. Typically, infection occurs through the consumption of dairy products and meat that have not undergone sufficient heat treatment.

The contact route of penetration of the pathogen into the human body through damaged skin or mucous membranes is also possible - through interaction with the wool, bedding, food and water of an infected animal. This explains the high incidence of brucellosis among livestock workers (milkmaids, shepherds, veterinarians, livestock specialists) and people involved in processing livestock products.

You can also become infected with brucellosis aerogenously by combing the fur from a sick animal or trimming it.

A sick person does not pose a danger to others. The exception is infection of the fetus from an infected mother.

After pathogens enter the body, they are captured by macrophages, multiply in them and penetrate the lymph nodes. From there, the bacteria spread throughout the body through the blood and lymph.

Symptoms of brucellosis

The presence of the disease can be assumed by a set of complaints such as excruciating pain in the joints (mainly in the legs) against the background of increased sweating, severe weakness, as well as wave-like fever (with a sharp rise and fall in body temperature).

The spread of the causative agent of brucellosis throughout the body causes systemic damage to almost all organs. Patients have pathologies of the musculoskeletal system in the form of monoarthritis, polyarthritis, osteomyelitis, and myalgia. Inflammatory processes are noted in the heart, lungs, and genitourinary system. Damage to the central nervous system in brucellosis is expressed in the form of meningitis, encephalitis, abscesses in the brain, and optic nerve atrophy.

Lymphadenitis (inflammation of the lymph nodes) and splenomegaly (enlarged spleen) are also characteristic of brucellosis.

Diagnosis of brucellosis

Collection of complaints and medical history, examination is the first stage of diagnosing the infectious process. It is important to obtain information about whether the patient is at risk.

Isolation of bacteria is necessary to confirm the diagnosis. This is possible by conducting a blood test for brucellosis in a person. Coombs, Wright, RSK (complement fixation reaction), PCR diagnostics - these research methods allow you to identify all forms of bacteria.

One of the simplest ways to diagnose an infection is the Berne skin test.

How and where is brucellosis treated?

Treatment of brucellosis consists of the following basic principles:

• measures aimed at combating the pathogen;
• elimination of pain syndrome;
• combating complications;
• restoration of working capacity.

Self-medication for brucellosis is unacceptable. In the acute phase of the infectious process and with the development of complications, hospital treatment is necessary. The selection of antibacterial and antiallergic drugs, physiotherapeutic procedures is carried out by the attending physician, depending on the phase and severity of the process, as well as existing complications.

How to prevent infection with brucellosis?

To prevent infection, doctors recommend following a few simple principles:

• observe the rules of personal hygiene, especially when it comes to contact with domestic and farm animals;
• thoroughly wash and heat-treat animal products;
• Do not ignore the symptoms that appear and consult a doctor immediately.

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Pathogenesis

Brucella are small bacteria that do not form spores, nonmotile, gram-negative. The causative agent of brucellosis can parasitize intracellularly. In works describing the microbiology of brucellosis, it is stated that the sources of Brucella dangerous to humans are: goats, sheep (pathogen Br.melitensis), pigs (Br.abortus suis), cows (Br.abortus bovis), dogs (Br.canis ). The pathogen is excreted in milk, amniotic fluid, and urine. The bacteria are quite viable; they can survive in the soil for up to 100 days. They die in a dry environment at a temperature of 90-95 degrees in one hour, in a humid environment at a temperature of 55 degrees Celsius in the same time. When boiled, brucellae die immediately.

Brucellosis carriers are animals with which humans come into contact. Animal brucellosis is a chronic infectious disease that occurs most often in cattle, pigs, and sheep. Brucellosis is often diagnosed in cows on farms, causing them to have abortions. Cattle experience loss of appetite, decreased activity, and increased temperature. Brucellosis in dogs causes problems with reproduction. Accordingly, the symptoms of brucellosis in dogs are manifested by disorders in the sexual sphere.

A person can also become infected by consuming products containing Brucella. The gateway to infection is microtrauma of the skin, mucous membranes of the digestive system and respiratory tract. Once infection occurs, most Brucella are rapidly eliminated by phagocytosis. But some of them remain viable in phagosomes. The pathogens enter the lymph nodes through the lymphogenous route, where they accumulate. When Brucella enters the bloodstream, the patient develops clinical signs of the disease. As a result of infection, a pronounced allergic restructuring of the body occurs. For a long time after cleansing the body of the pathogen, a pronounced delayed-type hypersensitivity is observed.

The disease is chronic. After a person has been ill, immunity , but it does not last long. Re-infection may occur after a few years.

Epidemiology of the disease and routes of infection

The causative agent of brucellosis is a bacterium of the genus Brucella. Eight varieties of Brucella have been identified, 6 of which are dangerous to humans.

Brucella are adapted to external conditions: they can withstand low temperatures, survive in soil, on the skin and fur of animals, in water, milk, and frozen meat. Under these conditions, bacteria can live from 1.5 to 5 months. Boiling kills microorganisms instantly; when heated to 60 °C, they die within 30 minutes.

The severity of the disease depends on what type of Brucella it is caused by. Acute and severe cases of the disease are most often caused by Brucellamelitensis.

The source of brucellosis infection is animals. The infection is mainly transmitted to humans from cows, goats, sheep, and pigs. Less often - from camels, horses and other animals. The bacterium is found in various biological fluids of animals - milk, feces, amniotic fluid.

Most often, infection occurs when a person consumes contaminated milk and its processed products (kumys, feta cheese, cheeses), or when processing hides and skin of sick animals.

Classification

The following types of brucellosis are distinguished according to the duration of the course:

• Acute – lasts no more than 3 months.
• Subacute – lasts from 3 to 6 months.
• Chronic – lasts longer than 6 months.

Taking into account the symptoms and characteristics of the course of the disease, the following clinical forms of brucellosis are distinguished:

• Primary latent – ​​a person feels practically healthy. If his immunity is weakened, this form can turn into another (acute septic or primary chronic metastatic). Sometimes, with this course of the disease, the lymph nodes become slightly enlarged, the temperature rises to low-grade levels, and sweating is noted during physical stress. At the same time, performance is maintained.
• Acute septic – fever (temperature rises to 40 degrees), chills and sweating are noted. These symptoms appear in waves. At the same time, health remains normal even at high temperatures, there are no signs of intoxication. Lymph nodes are moderately enlarged and sometimes sensitive. After a few days, the spleen enlarges. The condition is not life-threatening.
• Primary chronic metastatic - develops immediately, without an acute septic form. There is prolonged low-grade fever, insomnia , irritability, deterioration in performance and appetite. Lymph nodes are sensitive. The spleen and liver enlarge. Damage to organs, mainly the musculoskeletal system, is noted. The nervous and reproductive systems may also be affected. Joints and muscles hurt, polyarthritis , and other metastases . The lumbar spine may be affected. Possible neuritis, radiculitis , etc. Possible decrease in sexual function, amenorrhea . Other characteristic symptoms also appear.
• Secondary chronic metastatic - develops after the acute septic form, it is characterized by symptoms and manifestations similar to the primary chronic metastatic form.
• Secondary latent - differs from primary latent in that it recurs more often.

Causes

The cause of brucellosis is infection with microorganisms of the genus Brucella. There are the following methods of infection:

• Contact - a person becomes infected when he comes into contact with a sick animal and cares for it. Bacteria can get on the skin or mucous membranes with damage.
• Nutritional - when consuming contaminated products. You can become infected by eating animal products contaminated with Brucella. Most often, infection occurs when consuming raw milk, cheese or cottage cheese from unpasteurized milk, and less often when consuming insufficiently thermally processed animal meat.
• Aerogenic - this route of infection is very rare. Infection occurs when a person inhales dust containing the brucellosis pathogen.

Routes of transmission of brucellosis

• fecal-oral – through water and food;
• contact-household – the bacterium penetrates through microdamages of the skin and mucous membranes;
• aerogenic – inhalation of contaminated dust.

People who consume milk and dairy products without heat treatment are more likely to become infected through the fecal-oral route. Contact-household and airborne transmission routes are less common; they are mainly the cause of illness in those who care for animals and process products and raw materials obtained from them. If a pregnant woman suffers from brucellosis, there is a high probability of infection of the fetus or transmission of the infection to the baby during breastfeeding. Source: Features of the parasitic system of brucellosis. Gorchakova N.G. Scientific research publications No. 4, 2021. p. 14-27.

Symptoms of brucellosis in humans

Photos of symptoms of brucellosis in humans

The duration of the incubation period for brucellosis is from 5 days to several months. But most often it lasts about two weeks.

Symptoms of the disease may develop suddenly. The person begins to experience headache, fever, pain in the joints and lower back. There is a general malaise, sometimes accompanied by diarrhea .

But sometimes the symptoms increase gradually. In this case, the patient first feels a slight prodromal malaise, pain in the muscles and in the back of the neck, and he may also have a headache. After some time in the evening, his body temperature rises.

As the disease progresses, the temperature rises to 40-41 °C, and then gradually returns to normal. At the same time, in the morning a person sweats profusely.

In most cases, unstable fever is observed in the patient for 1 to 5 weeks, with remission observed for a period of 2 days to 2 weeks, during which the severity of symptoms decreases significantly. Sometimes the fever is transient, or it occurs in waves where it occurs periodically as a fever of unknown origin.

After the initial stage of fever with brucellosis, the following symptoms may appear:

• weight loss, anorexia;
• pain in the abdomen, joints, headaches;
• insomnia , weakness;
• irritability, depression ;
• tendency to constipation ;
• enlarged lymph nodes;
• hepatomegaly (in approximately half of patients).

However, systemic lesions can affect all organs. They are very diverse. In particular, disturbances appear in the activity of the musculoskeletal system, respiratory, digestive, genitourinary systems, heart, central nervous system, and vision.

Symptoms of the disease

The time that elapses from the moment of contact with the pathogen to the appearance of the first symptoms of brucellosis is from twenty to thirty days.

If the disease occurs in a latent form, the symptoms of brucellosis are prolonged for another month (sometimes even longer).

The disease begins instantly.

In people over sixty years of age, the onset of symptoms may have a gradual onset, as well as a protracted course of the disease up to four months. This presents significant difficulties in diagnosing this disease.

Brucellosis will be characterized by:

• malaise,
• insomnia,
• brokenness,
• arthralgia,
• myalgia,
• intoxication.

This clinical picture lasts for a week. The body temperature rises sharply to thirty-nine degrees, chills are noted, which are then replaced by cold sweat.

The period of fever lasts up to five days, but can last up to twenty (sometimes even up to thirty days). The patient complains of:

• sleep and appetite disturbances,
• pain in the occipital and frontal region,
• emotional tension and lability.

When the maximum temperature rises, the face of a patient with brucellosis becomes red and swollen, and the body remains pale.

An underlying disease is diagnosed - lymphadenopathy (lymph nodes are enlarged in the cervical and axillary areas). When palpated, sharp pain is revealed. The occurrence of fibrosis and cellulite is possible (seals form in tendons and muscles with a diameter of no more than one centimeter).

If the form is subacute, it will be characterized by the following symptoms:

• Relapses of the disease alternate: the high temperature returns to normal after a day. The maximum body temperature during fever reaches forty degrees.
• When the temperature rises, the patient complains of general weakness, a feeling of weakness, muscle pain, headache, loss of appetite and sleep disturbance. Characterized by paresthesia and rapid pulse. A crawling sensation in the lower limbs.
• On auscultation, muffled heart sounds are heard. In the lungs, breathing is vesicular, no wheezing is detected.
• The patient suffers from thirst, dry mucous membranes, and prolonged constipation.

In the subacute form, both fibrosis and cellulite occur. The development of ITS (infectious toxic shock) of varying degrees is possible. Complications of this disease include pericarditis, dermatitis, vasculitis, bursitis, the menstrual cycle is often disrupted, and endometritis.

If a pregnant woman is infected with brucellosis, the risk of termination of pregnancy cannot be excluded (depending on the trimester: medication, abortion or miscarriage).

The chronic form occurs with periods of remission and exacerbation. The symptoms of damaged organs and systems of the patient’s body worsen as a result of the disease.

Fever, malaise, nausea, headaches are pronounced, but are not as pronounced as in the acute period.

Up to two to three months can pass between exacerbation and remission.

If a new focus of infection appears in the body, the patient’s condition worsens sharply. The entire clinical picture will depend on how strong the protective forces of the patient’s immune system are, as well as on the pathogenicity of the causative agent of brucellosis.

In the chronic form of the disease, patients complain mainly of:

• Joint pain, tissue inflammation, deformation of the limbs (especially the feet), pain while walking.
• Changes in the joints (this can be either deformation or destruction of the joint).
• Inflammation of the nerves (visual and auditory occurs in seventy percent of cases).
• Ultimately, a reactive neurosis develops.
• An allergy that begins with inflammation of the glands of the reproductive system and ends with infertility for women and impotence for men.

The disease lasts for three years or longer. The patient's symptoms increase if the patient has been re-infected.

There is a concept of “residual brucellosis”. It means that this diagnosis is made when a complication of a previous disease is diagnosed.

Changed fibrous tissues remain in the body (nerve fibers, plexuses, and trunks are most susceptible to changes).

Ankylosis or spondylosis develops, muscle atrophy and contractures are possible. In this case, the purpose of correcting a particular pathology by surgery is considered.

The photo below shows the main triad of this disease. Symptoms of Brucellosis appear as follows:

Tests and diagnostics

During the diagnostic process, the doctor conducts a survey, determining whether the patient has had contact with animals or consumed thermally unprocessed food of animal origin. Other information is also important, in particular the patient’s place of work, the presence of endemic foci.

The clinical picture is taken into account.

To confirm the diagnosis, bacteriological, serological and skin-allergic methods are used.

A general blood test is required. An analysis for brucellosis is also practiced by inoculating blood on a nutrient medium. Special tests are carried out - Wright's reaction, Coombs' reaction, Heddleson's reaction, Burnet skin test, 2-mercaptoethanol-aglutinite test.

Diagnostic methods

To identify brucellosis, in addition to collecting anamnesis and examining the patient, laboratory diagnostics are necessary. It is carried out in institutions specially equipped to work with pathogens of particularly dangerous infections. To isolate Brucella from blood and other biological fluids, they are inoculated on special nutrient media. Sowing is not always carried out. To make a diagnosis of brucellosis, a serological reaction and the presence of antigens to Brucella in the patient’s blood are sufficient. Source: Nutrient media for the diagnosis of brucellosis. Kovtun Yu. S., Kurilova A. A., Katunina L. S., Vasilenko E. I. Problems of especially dangerous infections No. 4, 2021. p. 17-25.

Treatment with folk remedies

In folk medicine, there are methods that can help alleviate the condition of patients with brucellosis. But their use should in no case replace primary treatment. The following traditional methods of treating this disease are practiced:

• Carrot and celery juice. You need to mix 0.7 liters of fresh carrot juice and 0.3 liters of celery juice. Mix them and drink in three stages throughout the day.
• Grapefruit juice. It should be drunk fresh three times a day, 150 g.
• Bathhouse . This method is suitable for people who have developed rheumatism . You need to visit the sauna and massage sore spots with a broom. However, during a fever this should not be done under any circumstances.
• Sarsaparilla root. 100 g of sarsaparilla root should be mixed with 2 liters of grape wine. Leave for two weeks at room temperature. Drink 10 ml 1 hour before meals three times a day.
• Herbal collection. You need to take 1 tbsp. l. the following components: black elderberry flowers, nettle leaves, bean pods. Grind, mix, take 1 tbsp. l. mixture and pour 0.5 liters of boiling water over it. Leave for several hours, then drink half a glass 4 times a day.
• Second herbal collection. Mix the following ingredients: 4 tbsp. l. birch leaves, 5 tbsp. l. willow bark, 1 tbsp. l. buckthorn leaves. Mix everything and take 1 tbsp. l. mixture, pour 0.5 liters of water into it and boil for 20 minutes. Strain, drink 1 tbsp. 4 times a day, hot.
• Epsom salt. You need to add 150 ml of boiling water, 50 ml of carrot and orange juice to 1 liter of Epsom salt. Drink the mixture every half hour throughout the day. After this, you need to fast for 2-4 days, drinking only vegetable juices. Give enemas at night.

Prevention

To prevent infection with brucellosis, the following preventive measures should be practiced:

• Always boil raw milk or use pasteurized milk.
• Carry out veterinary control over animals with which people come into contact.
• Carry out preventive vaccinations for animals.
• Buy products of animal origin only in specialized places.
• People who come into contact with animals as part of their work must wear protective clothing.

In children

In children, this disease is generally milder than in adults. In the acute phase, as a rule, disorders of the nervous system are observed. Children sleep poorly, are irritable, and get tired quickly. Their blood pressure and their heart rate becomes unstable. In the acute form of brucellosis, pityriasis versicolor may appear on the skin of children in the form of white scaly spots. Sweating increases . Changes also appear in other systems - respiratory ( pneumonia , bronchitis ), digestive (worsening of appetite, colitis , dyspepsia ), cardiovascular. The liver, spleen, and lymph nodes become enlarged. Treatment should only be prescribed by a doctor. It is carried out by prescribing an antibiotic regimen, as for adults.

Treatment

Treatment depends on the form of brucellosis.

Acute therapy

• Treatment begins with the use of antibacterial drugs (chloramphenicol, streptomycin, tetracycline). Antibiotics are prescribed for fourteen days. Depending on the condition, longer use is possible.
• Next, glucocorticosteroid drugs (have an anti-inflammatory effect).
• Anti-inflammatory drugs (for example, aspirin, analgin, diclofenac are prescribed). These drugs are prescribed when joints are affected.
• Vitamin therapy (to stimulate the immune system).

Therapy for the chronic form (the symptoms are the same, but less pronounced)

• Broad spectrum antibiotics (the same as in the acute form). The duration is fourteen or more days.
• A killed therapeutic vaccine is used.
• Use of anti-brucellosis immunoglobulin.
• Drugs that suppress an allergic reaction to a particular component (suprastin, dimetrol).
• Drugs to stimulate blood circulation (methacyl or pentoxyl).
• UV irradiation (stimulates the immune system).

During pregnancy

Brucellosis is very dangerous for pregnant women, as it can cause abortion . Therefore, if a woman has suffered from this disease, she is not recommended to become pregnant for at least 4 months after all signs of the disease have disappeared. After all, there is a possibility that even after treatment, a certain amount of Brucella may remain viable in the body and provoke a relapse after some time.

If infection occurs during pregnancy , the prognosis for the fetus is unfavorable. If infected in the early stages, a woman may be advised to have an abortion. The fact is that the drugs used during therapy are extremely toxic to the fetus.

, a cesarean section may be recommended . If the period is short, the woman is hospitalized and monitored.

Treatment of brucellosis

The disease is treated in infectious diseases hospitals; severe cases are an indication for hospitalization of the patient in the intensive care unit. Since allergic reactivity is of great importance in the pathogenesis of the disease, an allergist-immunologist takes part in the treatment.

During the febrile period, patients are recommended bed rest, a diet with control of the level of incoming fluid and salt restriction.

The main therapy is antibiotics of different groups, most often a combination of two drugs is prescribed. In addition to this, detoxification, symptomatic and immunostimulating therapy is carried out.

During the period of remission, patients are recommended physical therapy, physiotherapy, and sanatorium-resort treatment. Source: Efficiency of etiopathogenetic treatment of chronic brucellosis. B. N. Kosherova. Medicine and ecology, 2012.

Diet

Diet 11 table

• Efficacy: therapeutic effect after a month
• Terms: 2 months or more
• Cost of products: 1800-1900 rubles. in Week

Diet 13 table

• Efficacy: therapeutic effect after 4 days
• Time frame: no more than 2 weeks
• Cost of products: 1500-1600 rubles per week

Patients with brucellosis in a state of fever are prescribed diet Table No. 13 , after stabilization of body temperature - Diet No. 11 . Patients with a chronic course of the disease do not require a special diet.

It is better to eat in small portions.

It is recommended to include the following products in the menu:

• Protein products - lean meat and fish, cheese, cottage cheese, other dairy products, eggs.
• Plant foods - berries, fruits, vegetables, herbs.
• Nuts, seeds.
• Vegetable and fruit juices are fresh.
• Porridge.
• Vegetable oils.
• Honey.
• Herbal decoctions.

Consequences and complications

With untimely or improper treatment, brucellosis can become chronic (up to 80% of cases).

Those who have recovered from brucellosis sometimes have residual signs of the disease: severe sweating, pain and deformation in the joints, irritability.

After brucellosis, the following complications may occur:

• bacterial endocarditis;
• neurobrucellosis;
• osteomyelitis;
• cholecystitis;
• liver abscesses;
• arthritis;
• epididymo-orchitis;
• enlargement of the liver and spleen, their soreness;
• meningitis , encephalitis .

During pregnancy, complications can include:

• arbitrary abortion (up to 30% of cases);
• fetal death in utero (about 15%);
• pathologies of fetal development (7-8%);
• premature birth (about 15%).

List of sources

• Brucellosis in the Russian Federation in 2001-2005: Information bulletin. — Moscow, 2007. 12 p.
• Zheludkov, M. M. Brucellosis in Russia: modern epidemiology and laboratory diagnostics: dis. ...Dr. med. Sciences / M. M. Zheludkov. - Moscow, 2009. - 263 p.
• Infectious diseases: national hands / ed. N. D. Yushchuk. - Moscow: GEOTAR-Media, 2009. - 1049 p.
• Handbook of differential diagnosis of infectious diseases. Edited by Professor A.F. Frolov, Professor B.L. Ugryumov, Dr. med. Sciences E.K. Trinus. Kyiv