1 / 27

Cholera

Cholera. Dept. Infectious Disease Shengjing Hospital CMU. Definition. Violent infectious disease of intestinal tract caused by vibrio cholerae International quarantine Pathogenic substance: choleragen Clinical features: profuse diarrhea & vomiting

jaeger
Download Presentation

Cholera

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cholera Dept. Infectious Disease Shengjing Hospital CMU

  2. Definition • Violent infectious disease of intestinal tract caused by vibrio cholerae • International quarantine • Pathogenic substance:choleragen • Clinical features:profuse diarrhea & vomiting Severe dehydration Muscular cramps Circulatory collapse Renal failure

  3. Etiology • Causative organism: vibrio cholerae • G-, short rod, similar to comma • Smear:arrange in shoal of fish • darting movement • Clinical diagnosis • growth on alkaline media

  4. Etiology • Pathogenicity- virulence • Choleragen • Endotoxin • enzyme • Resistance: Sensitive to heat, acid, common disinfectants. In river 1-3 weeks, sea food 1-2 weeks

  5. Etiology • Antigenicity: • Smatic “O” Ag; Flagella Ag: same • Serotype: • O1group: A, B, C AB- Ogawa,AC- Inaba, ABC-Hikojima • Atypical O1 group:Non-pathogenic • Non-O1 Group: O2-O200 O139 • Biological type: • Classical bio-type- O1group • EL-Tor bio-type- O1group • O139- Non-O1 Group

  6. Epidemiology • Source of infection Patients --(mild 18%, asymptomatic infection 75%); Carrier • Route of transmission Fecal-oral route mode of spread: water-borne(outbreak); food-borne(small epidemic); contagious spread • Susceptibility

  7. Epidemiology Epidemic features 1. Endemic and exogenous Classical biotype -- six outbreaks Since 1961-- El-Tor biotype which resulted the 7th outbreak. Since 1992--O139 biotype which resulted the 8th outbreak in the world. 2.Periodicity and seasons The peak of epidemic is between July and September summer & fall

  8. Bacteria Pathogenesis Small intestine Attach to brush border of epithelial cell choleragen endotoxin Movement of bowel B(binding subunit) + A1 Specific receptor GM1 CELL Adenyl cyclase Crypt cell:cl- H2o HCO3 ATP cAMP Cells of villus:Na+ reabsorb Diarrhea, dehydration

  9. Pathology andPathogenesis • Dominant pathological finding – dehydration • disturbance of electrolyte; • metabolic acidosis

  10. Clinical manifestation Incubation period:1 to 3 days Typical cholera: • Diarrhea & vomiting period: • Diarrhea:100%, rice watery stools with slightly fishy smell;10-20t/d ,no pain, no tenesmus, no fever • Vomiting:80%,after onset of diarrhea,no nausea,continuous and effortless.

  11. Clinical manifestation • Dehydration period: • Dehydration: • Circulatory collapse: hypovolemic shock • Muscular cramps: loss of Na+,in extremities(calves) and abdominal muscles • Disturbance of electrolyte: • Renal failure: oliguria-anuria- uremia • Convalescent period: • Fever: in 1/3 patients

  12. 2 004年1月27日一名霍乱患者被送到赞比亚首都卢萨卡的马泰罗霍乱治疗中心接受治疗

  13. Bucket with typical rice-water stool of a patient with cholera

  14. Clinical manifestation • Clinical type:according to degree of dehydration,BP,pulse,volume of urine • Mild type • Moderate type • Severe type • Fulminant type – Cholera Sicca

  15. Laboratory Findings • Blood picture:hemo-concentration • Urine test: pro. + ~ ++, RBC • Stool test: • Direct observation:darting movement Immobilized test: • Smear: G- arrange in shoal of fish • Culture: alkaline protein media • Serological test: haemagglutination

  16. Complications • Acute renal failure: • Acute pulmonary edema:

  17. Diagnosis • Epidemiologic data:travelling history; diet history; contact history • Clinical manifestation: • Laboratory findings: • Definite diagnosis: • Symptoms plus culture positive • Epidemiologic investigation, initial stool culture positive, diarrhea before or after 5 days • Epidemic period ,typical symptoms but culture is negative, without any other reasons

  18. Diagnosis suspected diagnosis: • Typical symptoms and first patient waiting for the result of culture • Epidemic period, contact history (+),diarrhea without any other reasons

  19. Differential diagnosis • Acute bacteria gastroenteritis • Viral gastroenteritis • Acute bacillary dysentery

  20. Treatment • General treatment: • isolation:when the symptoms disappear,stool cultures are negative for 2 times • Fluid replacement: • Intravenous fluid replacement: kind of fluid:541/321, 5%GNS, 0.9%NS, Ringer’ volume of fluid: speed of fluid replacement: • Oral fluid replacement therapy:

  21. Treatment • adult(ml/d) child(ml/kg.d) • Mild 3000-4000 100-150 • Moderate 4000-8000 150-200 • Severe 8000-12000 200-250

  22. Treatment • Etiological therapy: Antibiotics: deoxycycline for 3 days 1.reduce the duration and volume of diarrhea 2.shorten the period of bacterial excreta from the feces 3.diminish carrier after disease • Symptomatic therapy: eliminate acidosis and hypokalemia correct shock and heart failure

  23. Prevention • Control of source of infection: • isolation • International quarantine for 5 days • Interruption of route of transmission • Protection of susceptible population : Vaccinated with cholera vaccine 1.BS-WC 65-85% O1 Classical 2.CVD103-HgR 100% O1 group

More Related