Salmonella entiritidis - is the most common form of such bacteria in many countries, including the United States. This bacteria has recently attracted more and more attention of scientists because forms of this bacteria are becoming more attuned to the drugs used against them.
That is why public health authorities in many countries are paying great attention to the dissemination of Salmonella. It does not cause fatal disease. More often, the average deaths from salmonellosis is less than one percent. However, even the treatment of this disease does not cause difficulties in most cases. Usually doctors even do without the use of antibiotics. The greatest danger in this disease is dehydration. Doctors use special methods to correct a lack of fluid in the patient.
If the bacteria is beginning to migrate into the blood then the patient needs antibiotics. These bacterias are usually not a life-threatening. In many cases, a person feels completely healthy only after several months after recovery. Sometimes the pain in the joints remain until his death. Salmonella can also leave in the body such unpleasant phenomena as the deterioration of the vision or problems with the urinary system.
According to recent reports of American scientists some of these bacteria can exist even in fruits and vegetables. They also inhabit in bodies of many amphibians.
Classification of Salmonella
Species - salmonella enterica, genus - Salmonella (Latin salmonella), family-enterobacteriaceae (Latin enterobacteriaceae), order-enterobacteriaceae (Latin enterobacteriales), class - gamma-proteobacteria (Latin γ proteobacteria), type-proteobacteria (Latin proteobacteria), kingdom - bacteria.
Many serotypes of salmonella enterica are the causative agent of human diseases, including typhoid fever, paratyphoid fever, salmonellosis. Salmonella bongori is not pathogenic to humans. Species like salmonella enterica includes in its structure six subspecies (each of which has a number of serotypes):
- (I) enterica
- (II) salamae
- (IIIa) arizonae
- (IIIb) diarizonae
- (IV) houtenae
- (VI) indica
Subtype of S. enterica, previously designated by figure V, according to the modern classification, was extracted into a separate subspecies - S. bongori.
Subspecies Salmonella enterica includes the following serogroup:
- A (in this serogroup the best known is serotype paratyphi A)
- B (serotype: typhimurium, agona, derby, heidelberg, paratyphi B)
- С (serotype: cholerae suis, infantis, newport, muenchen, virchow, paratyphi C)
- D (serotype: dublin, enteritidis, moscow, rostock, sendai, typhi)
- E (serotype: anatum, london)
Salmonella S. typhimurium, S. enteritidis and other pathogens Salmonella
Most of Salmonella enterica species are pathogenic for humans , animals and birds, but in epidemiological terms the most significant to people are only few of them. 90% of cases of salmonella account for S. typhimurium, S. enteritidis, S. panama, S. infantis, S. newport, S. agona, S. derby and S. london. More than 50% of all diseases associated with Salmonella infection in the United States accounts for serotypes S.typhimurium and S. enteritidis, where the number of cases of salmonellosis, including in developed countries in recent years has increased. This is associated with the appearance of Salmonella strains S. typhimurium and S. enteritidis, resistant to modern antibiotics, and the spread of these strains around the world.
Salmonella S. Fever
One of the dangerous diseases caused by Salmonella is typhoid. The causative agent of typhoid is salmonella enterica serotype typhi (often called without specifying the species and subspecies: salmonella typhi). Typhoid fever affects only humans. Salmonella typhi is a short lively, bacteria, facultative intracellular parasite, growing well in the presence of oxygen, although it can grow in his absence. The optimum temperature for growth is 37 ° C but it can grow at temperatures ranging from 4 to 40 ° C. Good breeding ground for S. typhi is milk. Salmonella typhi and is viable outside the body: in the wastewater - within a week, in the faeces - from 1 to 2 months.
The incubation period lasts about 2 weeks. Infection with typhoid fever occurs with the entry salmonella typhi into the human body through the mouth. Infectious dose - 103-107 bacteria. S. typhi initially penetrate into the mucosa of the small intestine, where striking lymphoid clusters. With the flow of lymph S. typhi enter the bloodstream, where they collapse in large quantities. Liberated endotoxin causes the symptoms of the disease. Survived in blood S. typhi accumulate in the gall bladder, bone marrow, and spleen. Rash on the abdomen contains many salmonella typhi. In the further development of the disease S. typhi returns into the intestine through the bile ducts where it proliferates actively.
Immunocompromised patients or patients with reduced gastric acidity, have a higher risk of infection. For them, the disease is more likely to take place in a severe form. Regardless of the treatment the rate of mortality is 4%. From 1 to 4% of recovered patients remain carriers of S. typhi in the intestine or gallbladder for a few months or years.
Salmonella typhi is highly resistant to various antibiotics. In particular, its resistance to chloramphenicol reaches 100%, to ampicillin - 85%.
Salmonella S. paratyphoid A, B and C
Pathogens paratyphoid A, B and C is the type of Salmonella enterica subspecies enterica serotypeaccordingly, paratyphi A, B and C (often called without specifying the species and subspecies: salmonella paratyphi A, B or C). Salmonella paratyphi B is sometimes called salmonella schottmuelleri, and salmonella paratyphi C is sometimes called salmonella hirschfeldii. Salmonella S. paratyphi A and S. paratyphi B infect only humans.
Paratyphoids A and B have similar clinical manifestations and epidemiology of typhoid fever, differing more acute onset, less severe and shorter duration. Paratyphoid C as an independent disease is rare, most often it occurs in patients weakened by other diseases, and usually takes the form of food poisoning.