Bacillary dysentery

Bacillary dysentery (abbreviated as bacillary dysentery) is caused by Shigella bacteria. Shigella is divided into four groups: Group A (Shigella dysenteriae), Group B (Shigella flexneri), Group C (Shigella boydii), and Group D (Shigella sonnei). All four groups can produce endotoxins, and Group A can also produce exotoxins. All four types of Shigella can cause ordinary dysentery and toxic dysentery. Currently, the main pathogen of dysentery in China is Shigella flexneri, with an increasing trend of Shigella sonnei and Shigella boydii. Bacillary dysentery is transmitted through the fecal-oral route, meaning that eating food contaminated with the feces of dysentery patients and carriers can cause dysentery. The stool of dysentery patients contains a large number of Shigella bacteria and is therefore the main source of infection. Healthy carriers appear healthy on the outside, but their stool carries Shigella bacteria, so the role of carriers in transmitting dysentery cannot be ignored; they are a more dangerous source of infection. The feces of patients and carriers can contaminate food, fruits and melons, water sources, toys, and the surrounding environment through various means. Flies play an important role in transmitting Shigella bacteria. In summer and autumn, the weather is hot, flies breed quickly and are densely populated, and they prefer to rest in unclean places. Flies have many hairs on their feet, to which large numbers of Shigella bacteria can adhere. Therefore, flies are the unpaid carriers of Shigella and are important vectors of transmission. Thus, the incidence of dysentery rises significantly in summer and autumn. If children eat contaminated food or fruits and melons, play with contaminated toys without washing their hands properly before meals, or have a habit of finger sucking, the likelihood of contracting dysentery is very high. The population is generally susceptible to dysentery. Ordinary dysentery is most common in children aged 1 to 3 years, especially those who are malnourished or frail and frequently ill. Children who have had dysentery develop a certain degree of immunity, but it does not last long, and there is no cross-immunity between the different groups, so dysentery can occur multiple times within a year.