Listeriosis: Symptoms in humans, treatment and diagnosis

Listeriosis - a rare disease caused by germs Listeria monocytogenes, which may be present in the soil, some foods, animal feces. The main vectors are the birds and animals.

Pathogenic microorganisms are stable in the environment. They are able to persist and multiply in the soil at moderate and low temperature for many months. Furthermore, Listeria monocytogenes bacteria can exist in milk and meat at a temperature of 4-6 ° C. When boiling die within 3-5 minutes.

Epidemiology

Listeria infects the central nervous system and can cause meningitis and encephalitis. Unfortunately, listeriosis and leads to death. The disease is most prone to a certain group of people. This pregnant women, newborns, the elderly and people with weakened immune systems.

According to the American Center for control and prevention of diseases in the United States in the year registered about 1,600 cases of listeriosis illnesses. Moreover, the number of deaths from listeriosis - about 260.

Published February 21, 2017 the results of the study Madison School of Veterinary Medicine (USA) It showed that Listeria can also bring a miscarriage already in the early stages of pregnancy (the first trimester). Earlier listeriosis only recognized at a late stage of pregnancy (third trimester), and its impact at an early stage has not been studied.

How, then, can a person get sick? Allocate the following transmission path:

1. Aerogenic - inhalation of fluff, dust in the processing of hides of infected animals.
2. Pin - when in contact with infected animals or their metabolic products through the damaged skin, mucosa, conjunctiva.
3. Alimentary - infection occurs in the use of meat, milk, cheese, eggs from a sick bird (animal), vegetables, salads, water contaminated with secretions of patients with rodents.
4. Transmissible - by the bite of ticks and fleas parasitizing on the sick animal;
5. Vertical - infections transmitted from mother to child in utero.

At the same time he primary method of listeriosis infection - is food. The bacterium enters the body with food, which in turn become infected during production and storage. At the same time, faced with frequent cases of infection with listeria in the food business, in most cases we did not know what was the cause of the contamination. However, there are several studies showing the areas allocated for any Listeria in the production hall.

The causative agent of listeriosis

The causative agent of the disease was first described in 1911 by S. Halfesom. A singled him from sick guinea pigs and rabbits D. Murray in 1926. The very name of Listeria was proposed in 1927 by W. Piri after Joseph Lister. In 1929 we revealed A. Nifelltom Listeria bacteria from a person with a high monocytosis. And in 1935, K. Bern listeriosis cases are found in women in childbirth and newborns.

The causative agent acts asporogenous, mobile, gram-positive bacillus Listeria monocytogenes, which is the type species of the genus Listeria. The causative agent of listeriosis or may form a capsule acquire L-form, as well as parasite within the cells, thus determining the slow development of infection.

The causative agent of listeriosis undemanding and able to grow on ordinary media at any temperature, and is ready for reproduction in water, soil, cadavers in plants, foods. The causative agent of listeriosis is only sensitive to broad-spectrum antibiotics, but there are resistant strains. Pathogen Listeria released from the human body together with the secrets (blood, urine, milk, semen, rectal mucus, cerebrospinal fluid, amniotic fluid). Puerperal and newborn children are able to allocate the causative agent of up to 12 days after birth.

The initial source of infection are the wild and synanthropic rodents with different objects of an environment.

symptoms of listeriosis

In the case of acquired listeriosis incubation period in humans - 2-4 weeks.

The major clinical forms:

1. Eye-glandular form develops the penetration of Listeria through the conjunctiva ( "swimmers disease") and is characterized by fever, loss of appetite, headache pain, general weakness, swelling and redness of the eyelids, eye narrowing of the gap, purulent discharge in the corner of the eye, increase in size and tenderness of the lymph nodes.
2. Anginal (mononucleosis) form of listeriosis has the following symptoms: fever, decreased appetite, headache, weakness, sore throat, swollen lymph nodes.
3. Typhoid form has listeriosis manifestations such as prolonged fever; rash from spotty to sinyachkovoy; sore throat and conjunctivitis are absent. Typhoid form of listeriosis usually occurs in immunocompromised children and also in neonates and infants. Listeriosis nervous system can take place in the form of meningitis, encephalitis, meningoencephalitis. During heavy. After this illness possible residual effects in the form of mental disorders, neurodevelopmental development of paralysis. The most common form of listeriosis in adults.

Congenital fetal infection listeriosis can occur either in utero, at any stage of pregnancy (but not before the 5 th week) and during childbirth. Therefore, the outcome of infection may be different: spontaneous abortion, stillbirth, birth of children with developmental disabilities - with the defeat of the fetus in the first half of pregnancy; or the birth of a child with congenital listeriosis - during later infection.

Clinical manifestations of congenital listeriosis are not specific. There are:

• lethargy, confusion;
• change of heart;
• high fever;
• violation of appetite (refusal of feeding);
• regurgitation or vomiting;
• liver disease (jaundice);
• cyanosis, "marbling" of the skin;
• hives nodular (bumps), spotty or sinyachkovaya;
• meningitis and meningoencephalitis (excitation or depression of consciousness).

Congenital listeriosis - one of the most severe cases of infection, with high risk of death.

Listeriosis in pregnant women

Pregnant women significantly increases the risk of infection. This is due to the fact that during pregnancy decreases the body's immune system and metabolism changes. Women are more difficult to tolerate all kinds of infections, including listeriosis.

The most common symptoms of listeriosis in pregnant women include:

• slightly manifested flu symptoms - fever, muscle pain and back pain, intermittent feeling of chill and fever;
• stomach upset;
• cramping abdominal pain.

If you do not start early treatment of listeriosis in pregnant women can be severe consequences. Especially dangerous is the disease after 14 weeks of pregnancy. Sometimes listeriosis causes premature termination of pregnancy, premature birth and even stillbirth. It increases the risk of miscarriage and analysis procedure itself. Ultrasound examination of pregnant women makes it possible to see the changes in the child's organs, which can be caused by a causative agent of listeriosis.

Diagnosing listeriosis

For the diagnosis of listeriosis have to rely on the symptoms and the patient's complaints, findings of epidemiological history.

Help confirm the diagnosis of laboratory and instrumental studies:

1. PCR (detection of Listeria DNA fragments);
2. Analysis of the cerebrospinal fluid (pressure increase neutrophil or lymphocyte-neutrophilic pleocytosis, increased protein levels);
3. Complete blood count (leukocytosis characteristic, increasing the number of monocytes, accelerated erythrocyte sedimentation rate, platelet reduction);
4. Serological methods: ELISA, RA, Phragmites, RAC (to determine specific antibodies to Listeria);
5. Bacterial inoculation biomaterial patient (mucus from the throat, blood, cerebrospinal fluid, eye discharge, urine, lymph node biopsies).

Treatment of listeriosis in humans

For suspected listeriosis patients compulsorily hospitalized in the infectious ward.

Treatment is carried out in special boxes. Person has recommended drinking plenty of fluids and a diet rich in vitamins. Treatment complex, depending on the predominant form of the disease. All patients shows antibiotic therapy (tetracycline, erythromycin, levomitsitin). Antibacterials are appointed for the duration of elevated body temperature and for a further 5-7 days after normalization of temperature.

For treatment of intoxication illustrated drip infusion of various solutions (isotonic sodium chloride solution, Ringer's solution) against drugs that stimulate the excretion of urine. For the treatment of eye-glandular topically applicable forms of listeriosis Albucidum solution and glucocorticoids.

Length of hospital stay varies depending on the form of the disease and varies from 14 to 28 days. It is believed that after the normalization of temperature and the disappearance of the major clinical manifestations of the disease the patient becomes contagious and can be discharged from the hospital. After hospital discharge, the patient is under the supervision of infectious disease within two years.

prevention

Vaccinated against listeriosis does not exist. Nor is it possible to protect yourself from this disease is one hundred percent. The only way to reduce the risk of infection is strict personal hygiene, veterinary and hygiene standards at the pet as well as a minimum of contact with animals living in Wild.

Each person should take measures to protect against the infection of their family and themselves. First of all, these measures consist in thorough heat treatment of food: milk should be boiled and meat products and meat are carefully boil thoroughly and roast thoroughly. Meat fresh should be stored separately from other products. It is also the cause of the infection may be eating meat with the blood. Before the use of fresh fruits and vegetables they should be thoroughly rinsed. In addition, although it is obvious, it should be noted that you should not drink water from lakes or rivers without any treatment or boiling.

On livestock farms in contact with the cattle need to use personal protective equipment - respirators, gloves, overalls, protective masks. You also need time to treat animals and to combat rodents.

Patients should be sent immediately with suspected listeriosis in a special box in a hospital, in order to eliminate the possibility infikatsii others. Discharge from the hospital only after the confirmation of the absence of bacteria in the analyzes.