Cholera

Overview cholera (cholera) is caused by Vibrio cholerae of acute gastro-intestinal infections. Clinical manifestations range, while the only mild diarrhea; Severe vomiting, diarrhea keen large Miganshui kind faeces and caused severe dehydration, and the pH imbalance and the surrounding circulatory failure and acute renal failure. Cholera in India since ancient times that the Ganges River delta endemic, 1817 ~ 1923 for more than 100 years between the six world pandemic. At 1883 Fifth pandemic, koch from the stools of patients with Egypt for the first time discovered the cholera vibrio. 1905 Cotschlich in Egypt's Sinai Peninsula EL-Tor quarantine stations from the pilgrimage to Mecca from the body pm from similar Vibrio cholerae strains, named EL-Tor Vibrio after EL-Tor caused by the disease known as Vibrio cholerae. Because both bacteria in the form and characteristics of the basic serology, clinical manifestations and prevention are identical, Therefore, in May 1962 the 15th session of the World Health Assembly decided to diseases caused by both collectively referred to as cholera. In 1820 the disease spreading to China, the world's largest Before each epidemic will spread in China, which has caused more than 100 popular size, After the liberation of almost disappeared, but in recent years, frequent exchanges with foreign countries, which can easily re-imported from abroad. Pathogenic bacteria Vibrio cholerae belonging Branch Vibrio, according to the biological traits can be divided into classical biological and EI Tor biotype. Bacterial short, slightly bent, Gram staining, and no spores of Clostridium in length and 1.5-2.0μm. 0 .3-0.4 μm wide. End of a bacterial flagellum, an extremely lively campaign in the dark field microscopy was like a meteor flashing past and the fecal smears were listed stocks. In alkaline (Ph8.0 ~ 9.0) peptone medium easy to grow. Vibrio cholera bacteria with heat (O) antigens and the heat-resistant organism (H) antigen. According to the O-antigen cells can be divided into different at least 78 serogroups. Classical and EI Tor type is O-1 Vibrio cholerae, the international quarantine of infectious pathogen detection to O-1 group prevail. Bacterial antigens A, B, C three ingredients. A O-1 group-specific antigen; According to the bacterial antigen components can be divided into three serotypes, rice leaf type (Inaba, prototype, containing AC), Ogawa (Ogawa, dysplasia, including AB) and the island-yin (Hikojima. intermediate, with ABC). Classical Vibrio outer environment viability is limited, but strong resistance-type EI Tor. In general the untreated river water, sea water and well water, viable EI Tor-1 ~ 3 weeks or even longer. Two pairs of hot, dry, pounded the sunlight and the general disinfectant very sensitive, Heating 100 ℃ a two-minute exposure to sunlight or a two-hour deaths, 2% bleaching powder. 0.25% peracetic acid solution of potassium permanganate and 1:500000 a few minutes to kill. Epidemiology (1) the source of infection in patients and carriers of cholera infection source. Severe vomiting, diarrhea-infected patients more vulnerable to pollution of the environment, and is an important source of infection. Light and asymptomatic patients infected as a source of infection more meaningful. Recently there animals (including aquatic animals) as a source of infection reports that deserves attention. (2) transmission of the disease through water, food, living in close contact with the media and the spread of flies, on a water-borne most important. Vomiting, diarrhea patients and HIV carriers from faecal contamination of water after easily cause local outbreak. Usually first occurred in the border areas, coastal ports and rivers, coastal areas and water network, and then by sea, by land, air traffic transmission. (3) the susceptibility crowd generally susceptible. Adult onset of new infected areas, the old-affected areas and the high incidence of children. Vibrio cholerae infection after the body depends on whether the incidence of non-specific and specific immunity, such as the acid pH, SIgA, and the intestinal serum antibodies specific lectin, bactericidal antibody and anti-toxin antibodies to the effect. Entitled to a certain disease after immunity. (4) Since the popular 1817 feature classical type Vibrio world pandemic, has spread to more than 100 countries and regions. Particularly early in 1991 occurred in South America, the epidemic has not yet been extinguished. only 91 year cumulative incidence worldwide has more than 50 million people, has become a focus of biological hazards. 1. 2-distribution of Vibrio cholera are endemic foci, India has been called the "hometown of human cholera, known as" Indonesia's Sulawesi is EL-Tor Vibrio foci, each of the world from the pandemic is spreading from above. China is exogenous, the previous world epidemic will suffer. 2. Seasonal distribution of the incidence in the general season five-November, and more popular peak in the 7-October. 3. Pop style and persistent outbreaks distributed in two forms, which often through water or food-borne outbreak caused, more common in the new area, but the latter occurred in the old-affected areas.