阿米巴病（英文）.ppt

AMEBIASIS
DISTRIBUTION
Ameba has worldwide distribution but is most common in central and south America, southern and western Africa, the far east, and the India
 >10% of the world’s population is infected.
The second leading cause of death from parasite disease
*
Etiology
4 species of Entamoeba :
E. hartmanni
E. coli
(Pathogenic)
E. dispar (asymptomatic)
*
intestines
Entamoeba histolytica
One of the most important and pathogenic parasites of humans
50 million cases every year,
100,000 died
*
*
Microbiology
2 forms：trophozoite; cyst
*
Life cycle
cyst
postcyst
trophozoite
precyst
Entamoeba histolytica Trophozoites
*
Entamoeba histolytica
Dormant/resistant stage
Spherical
1-4 nuclei, (4 in mature cysts)
Bluntly rounded chromatoidal bars
*
Entamoeba histolytica Cysts
*
Entamoeba histolytica Cysts
Uninucleate cyst Binucleate cyst
*