传染病学：3霍乱(英文)

Classification of vibrio cholera by WHO
O1 vibrio cholera Non-O1 vibrio cholera Untypical-O1 vibrio cholera
O1 vibrio cholerae
According to the phenotype，two biotypes were typed：
epidemic history
1st～6th pandemic（1817～1923）：clssical biotype
7th pandemic（1961～up to now）：El Tor biotype
In 1992, cholera caused by O139 serotype began in India and Bengal, and spread to surrounding countries（8th pandemic）
Cholera
Fra Baidu bibliotek
cholera
Pathogen：vibrio cholera
Eight pandemics over most of the globe
A infectious disease
international quarantine infection disease
etiology
vibrio cholerae
Even survive for more than one year, if external environment was suitable
Three types of toxin
Ⅰtype toxin ——endotoxin，the major component of bacterial vaccin Ⅱtype toxin——epitoxin，is cholera enterotocin，
antigen
Bacterial cell（Ｏ） antigen———has high specificity, and is the basis for the classification and typing of vibrio cholera
Flagellum （Ｈ） antigen———common in vibrio cholera
Gram-negative It is rapidly motile by means of a single polar flagellum. O139 serogroup with capsule Hanging drop test under microscope Appearing school of fish in feces smear Generate rapidly in the alkalinity environment
O139 serogroup has following specificities：
A new serogroup detected in Bengal in 1992 With the same toxin gene with O1 serotype，and leading to epidemic diarrhea
Sensitive to heat, dry ,acid and common antiseptics
Die after drying for 2 hours or heating to 55℃ for 10 minutes
Die immediately after boiling
Survive for 4 minutes in the normal gastric acid
classical biotype El -Tor biotype
According to the O antigen， V. cholerae O1 are further divided into the following subserotypes ：
ogawa(小川） strains express A and B antigens inaba （稻叶） strains express A and C antigens hikojema 颜岛）strains express A, B and C antigens
Product of metabolism in the generation of vibrio cholera Key substance leading to cholera diarrhea
Ⅲ type toxin has no association with pathogeny
epidemiology
Resistance of vibrio cholerae
Survive more longer in physical environment
El Tor biotype can survive for 1-3 weeks in river and well water
Survive time prolonged as adhere to algae or crustacean
non- O1 vibrio cholerae
No ability to agglutinate the multipartial serum of O1
vibrio cholerae
Containing more than 200 serogroups such as O2,O3,O138 and so on， with no pathogenicity generally
cases of vibrio cholerae in 1961-2000
untipical- O1 vibrio cholerae
With the ability to agglutinate the
multipartial serum of O1 V.cholerae
With no enterotoxin and pathogenicity
Resistance of vibrio cholerae