Case: According to reports, cold cabbage, peanut rice, tofu brains and fried cakes were the breakfast and lunch that students ate at school on Oct. 17. starting in the early morning of Oct. 18, students were sent to the hospital one after another with fever, vomiting and diarrhea, and nearly 300 people were sent to the hospital for treatment before and after similar symptoms. The local CDC found Shigella sonnei in the patients’ excrement and initially diagnosed it as food poisoning caused by Shigella sonnei.
What is shigellosis?
Shigella spp. is a class of Gram-negative bacilli, the most common pathogen of bacteriophage dysentery, commonly known as dysentery bacilli. Bacterial dysentery (bacillary dysentery), which we have often heard of, is an intestinal infectious diarrhea caused by Shigella dysenteriae, which is one of the most common intestinal infections in summer and autumn. Bacillary dysentery is divided into four groups: A, B, C and D. Shigella sonnei belongs to group D.
Symptoms and signs
The incubation period of dysentery varies from a few hours to 8 days, mostly 2 to 3 days. According to the clinical manifestations, it is divided into common dysentery, toxic dysentery and chronic dysentery.
(1) Common dysentery: Most of the dysentery is common type. The onset of dysentery is rapid, with chills and fever, temperature often above 39℃, headache, fatigue, vomiting, abdominal pain and shortness of breath. Pain in the left lower abdomen is obvious. Diarrhea is frequent, with dozens of stools per day, even uncountable. Because the rectum is often irritated by inflammation, there is always a desire to relieve the stool, but not much can be relieved, and this phenomenon is called posterior urgency. Frequent diarrhea can lead to dehydration.
(2) Toxic dysentery: This type of patient is mostly 2 to 7 years old children. Most children have a sudden onset, high fever and even coma. If the child suddenly has high fever and convulsions, is very weak and ashen, the child should be sent to hospital immediately for examination and rescue.
(3) Chronic dysentery: rare, mostly due to untimely diagnosis, incomplete treatment, bacterial drug resistance, weakness of the patient, the course of the disease more than 2 months.
Transmission of shigellosis
Dysentery is an intestinal infectious disease from the mouth, mainly through fecal-oral transmission, there are four main ways of transmission as follows
1. food-type transmission: eating cold food and unclean fruits and vegetables can cause bacillary dysentery. Bacterial cooks and contaminated food with dysentery bacillus do cold food, etc., can often cause bacillary dysentery outbreaks.
2. Water-type transmission: dysentery bacillus contaminated water can cause an outbreak of epidemic. If the patient and the carrier of feces improperly handled, poor water protection, fecal contamination of natural water, well water, tap water without disinfection drinking, is often the root cause of bacillary dysentery outbreaks.
3. Daily contact type transmission: mainly through contaminated hands and spread, this kind of living contact is the main way of transmission in the non-epidemic season. Such as tables, chairs, toys, door handles, handrails, etc., can be contaminated with dysentery bacilli, if the hand contact with the above contaminated products, can carry bacteria, if immediately to grab food, or children have the habit of sucking fingers, the bacteria will be sent to the mouth and cause disease.
4. Fly transmission: flies have the habit of both feces and food, which can easily cause food contamination and cause disease.
Shigellosis prevention
Floods make people’s living environment bad, especially water is seriously contaminated, deteriorating dietary hygiene and poor living conditions, the possibility of local outbreaks of bacterial dysentery is great.
The main preventive and control measures for bacteriophage dysentery are
1. to improve food hygiene, to ensure water hygiene, make a good report of the epidemic, immediately after the emergence of the epidemic, identify and control the source of infection, prohibit patients or carriers of bacteria in the catering industry and childcare, and limit large gatherings.
2. personal hygiene, do not drink raw water, use disinfected water to wash fruits and vegetables and dishes and gargle; wash your hands before and after meals, do not defecate anywhere; eat cooked food not cold dishes, leftovers should be heated and eaten; do separate raw and cooked food, prevent flies from climbing food; seek medical treatment in a timely manner after getting sick.