Paratyphoid

Paratyph - acute infectious diseases, similar in etiology, epidemiology, pathogenesis, morphology and clinic with typhoid fever. Allocate paratyphoid A, B and C.

ICD-10 code

A01. Typhus and paratyphoid.

Epidemiology of paratyphoid

The paratyphoid share accounts for about 10-12% of all typhoid paratyphoid diseases. For a long time, paratyphoid A and B were described as an easy variant of typhoid fever without a clear clinical picture. At the same time, they were more often limited to data on their differentiation with typhoid fever.

Paratyphes A and B are typical intestinal infections, anthroponoses, found everywhere. Before World War I, paratyphoid B was more common in our country, both diseases are now quite common. Paratyphoid C as an independent disease is rarely recorded, usually in individuals with immunodeficient conditions.

The main source and reservoir of infection is a sick or bacterial carrier, releasing pathogens with feces, urine and saliva. The patient with paratyphus begins to excrete the pathogen in the environment with feces and urine from the first days of the disease, but the greatest intensity of bacterial release reaches at the 2-3rd week of the disease. After the transferred paratyphoid can be formed acute (up to 3 months) or chronic (over 6 months) bacteriocarrier. Chronic carriers are 5-7% of persons who have transferred the paratyphoid. There are no reliable data on the infection of humans with paratyphoid A and B from animals.

As the incidence of paratyphoid decreases, the role of bacterial carriers as sources of infection increases in comparison with patients. Especially dangerous are they, if they work at the enterprises for the production of food products, trade, public catering, in medical and children's institutions, in the water supply system.

Mechanism of transmission of paratyphoid pathogens A, B. With fecal-oral. Transmission factors are food, water, household items, infected with sick or bacterial carriers, and flies. There are sporadic cases as well as epidemic outbreaks.

If there is a violation of the sanitary content of the wells or other open water bodies, they easily become polluted, including sewage. Water paratyphoid epidemics can occur in the event of a water supply failure when connecting technical water supply, are more common in paratyphoid A.

The food path for the distribution of paratyphoid, especially paratyphoid B, is primarily associated with the use of infected dairy products, as well as products not subjected to heat treatment after cooking: salads, jelly, ice cream, creams. Food flashes of paratyphoid A are less common than paratyphoid B.

Infection by the contact-household way is possible from chronic bacterial carriers, less often - from patients in violation of the sanitary regime.

If in the settlements there is an increased incidence of paratyphoid, then usually observed its seasonality, associated primarily with infection through water, poorly washed berries, fruits, vegetables. With a low incidence of paratyphoid morbidity, the seasonal ascent is flattened or absent altogether.

[1], [2], [3], [4], [5],

What causes the paratyphoid?

Paratyphoid bacteria - an independent species of microorganisms of the genus Salmonella, causative agent:

• paratyphoid A - S. Paratyphi A;
• paratyphoid B - S. Schotmuelleri;
• paratyphilis C - S. Hirschfeldii.

In form, size, tinctorial properties, they do not differ from typhoid; biochemically more active, especially S. Schotmuelleri, which is in accordance with less pathogenicity for humans. They have somatic (O-antigen) and flagellate (H-antigen) antigens. Pathogens are well preserved in the environment, including in drinking water, milk, butter, cheese, bread, are relatively resistant to the effects of physical and chemical factors, persist for a long time at low temperatures (in ice for several months). At boiling die instantly.

Recently, there is a need for differentiation of the paratyphoid B causative agent from S. Java, which is attributed to group B salmonella and which has the same antigenic structure with S. Schotmuelleri, but differs from it in biochemical properties. S. Java often stands out from animals, causes foodborne toxic infections in people who mistaken for paratyphoid B.

Pathogenesis of paratyphoid

The pathogenesis of paratyphoid A, B. C and typhoid does not differ in principle.

At paratyphoid, more often than in typhoid, the colon is affected and the destructive processes in the lymphatic apparatus of the intestine are less pronounced.

Symptoms of paratyphoid

Paratyphoid A is usually characterized by typhoid (50-60% of patients) or catarrhal (20-25%) forms. Unlike typhoid fever, paratyphoid A occurs more often in a moderate form and in the initial period is manifested by flushing of the face, injection of a sclera, cough, and runny nose. These paratyphoid symptoms make the initial period of paratyphoid A similar to ARVI. The rash appears on the 4th-7th day of the disease in 50-60% of patients. Along with a typical rosaceous rash, it is possible to detect maculopapular elements reminiscent of measles exanthema. Some patients are met with petechial elements. The rash is more plentiful than with typhoid fever. There is no characteristic type of fever with paratyphoid A, but still more often there is a remitting fever. Rarely there are relapses and complications.

In paratyphoid B the gastrointestinal form is more common (60-65% of patients), less often typhoid (10-12%) and catarrhal (10-12%) forms. Distinguishing symptoms of paratyphoid B - signs of gastroenteritis, arising from the first days of illness. In the future, fever, exanthema, represented by roseola, is much more abundant and elevating than with typhoid fever. Temperature is often wavy, with a large daily amplitude. The severity of paratyphoid B can be different - from erased and abortive to very severe forms, but in general it proceeds more easily than paratyphoid A and typhoid fever. After the transferred paratyphoid B, persistent immunity is formed, relapses occur infrequently - in 1-2% of patients. Occasionally, such formidable complications as perforation of the intestine (0.2%) and intestinal bleeding (0.4-2% of patients) may occur. There are also nonspecific complications: bronchopneumonia, cholecystitis, cystitis, parotitis, etc.

Symptoms of paratyphoid C are characterized by intoxication, muscle pain, jaundice of the skin, fever.

Diagnosis of paratyphoid

Diagnosis of the paratyphoid is the bacteriological study of feces, blood, urine, vomit and gastric washings, as well as the detection of antibodies to Salmonella in RIGA, Vi-agglutination reaction with typical sera and / or linear RA (Vidal's reaction). As antigens monodiagnostics are used for specific pathogens. Studies recommend starting from the 7th day (the rise time of the antibody titer).

[6], [7], [8], [9], [10], [11]

What is the prognosis of the paratyphoid?

Paratyph has a favorable prognosis provided timely and adequate treatment. Treatment of paratyphoid, preventive measures, clinical examination, recommendations at discharge - see " Typhoid fever ".