CDC Cholera Outbreak Notices - Haiti, 2010

[Missouriwatcher]

(CDC) October 28, 2010
An outbreak of cholera is ongoing in Haiti. On October 21, 2010, toxigenic Vibrio cholerae O1, serotype Ogawa, biotype El Tor was identified by the National Laboratory of Public Health of the Ministry of Public Health and Population in Haiti. Identification of the isolate was confirmed by CDC. Antimicrobial susceptibility testing of selected V. cholerae O1 isolates conducted at the National Laboratory of Public Health and at CDC demonstrated susceptibility to tetracycline (susceptibility to this drug predicts doxycycline susceptibility), ciprofloxacin, and kanamycin; and resistance to trimethoprim-sulfamethoxazole, furazolidone, nalidixic acid, sulfisoxazole, and streptomycin.

As of October 27, a total of 4,722 cholera cases with onset during October 21--27 and 303 deaths had been reported in Haiti. Most cases have been reported from Artibonite Department, a rural but densely settled area with several small urban centers. In addition, probable cases have been identified elsewhere in Haiti, including Ouest Department, where the capital city of Port-au-Prince is located.

... Epidemic cholera has not been reported previously from Haiti; the population is immunologically na?ve and therefore highly susceptible to infection with V. cholerae. The outbreak appears to have spread from an initial concentration of cases in Artibonite Department. An international public health response, led by the Ministry of Public Health and Population and including technical support from the Pan American Health Organization, CDC, and other governmental and nongovernmental organizations, is under way. The emphasis of the response is on 1) minimizing mortality by using oral rehydration for most cases and intravenous rehydration for severely ill patients and 2) preventing infection by promoting water treatment, adequate sanitation and hygiene, and safe food preparation.

No cases of cholera in travelers from Haiti to the United States have been reported to CDC...

More information on cholera, including recommendations for treatment, laboratory testing, and scientific publications, is available at http://www.cdc.gov/cholera. Further information regarding the outbreak in Haiti is available at http://www.cdc.gov/haiticholera.

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm59d1028a1.htm?s_cid=mm59d1028a1_e

[Missouriwatcher]

Re: Cholera Outbreak - Haiti, 2010

Update: Cholera Outbreak --- Haiti, 2010
...This report describes the investigation of the initial cases, the ongoing outbreak of cholera in Haiti, and initial control measures. Since the initial identification of cholera, the outbreak has expanded to include cases in seven of Haiti's 10 departments and the capital city of Port-au-Prince. As of November 13, MSPP had reported 16,111 persons hospitalized with acute watery diarrhea and 992 cholera deaths, 620 of which occurred among hospitalized patients...

Initial Epidemiologic Investigation
During October 21--23, the investigative team used a standardized questionnaire to interview a convenience sample of 27 patients in the five hospitals in Artibonite Department. Most of these patients resided or worked in rice fields in communities located alongside a stretch of the Artibonite River approximately 20 miles (32 kilometers) long. Eighteen (67&#37 of the 27 hospitalized patients reported consuming untreated water from the river or canals before illness onset; 18 (67%) did not routinely use chlorine for treating water, and 21 (78%) practiced open defecation.

Cholera Surveillance and Laboratory Findings
A suspected case of cholera is defined as profuse, acute watery diarrhea in a patient. A confirmed case of cholera requires laboratory confirmation by culture of V. cholerae. When a department reports a case of laboratory-confirmed cholera, the department is declared "cholera affected." Only reports from cholera-affected departments are tallied and included in the MSPP daily surveillance summaries.

Since the initial identification of cholera in Artibonite and Centre departments, the outbreak has expanded to include cases in five additional departments and the capital city; cases have been reported in seven of 10 departments (Artibonite, Centre, Nord, Nord' Ouest, Nord' Est, Ouest, and Sud) and Port-au-Prince. As of November 13, MSPP had reported 16,111 persons hospitalized with acute watery diarrhea and 992 cholera deaths, 620 of which occurred among hospitalized patients (case-fatality rate among hospitalized patients: 3.8%). Cases and deaths have been reported primarily from Artibonite department (63% of cases and 62% of deaths).

At LNSP, the outbreak isolates were identified as V. cholerae serotype O1, serogroup Ogawa, and selected specimens were sent to CDC for confirmation and additional analyses. As of November 13, CDC had isolated V. cholerae from 14 specimens received from LNSP. All isolates were identified phenotypically and characterized by serotyping, biotyping, antimicrobial susceptibility testing, and by pulsed-field gel electrophoresis (PFGE), performed using a protocol developed by PulseNet International, the international molecular subtyping network for foodborne and waterborne disease surveillance. Additionally, the isolates were characterized genetically for the presence and subtype of certain virulence factors (e.g., the cholera toxin, genes specific for strains associated with the ongoing cholera pandemic, and antimicrobial resistance genes). The 14 isolates associated with the outbreak in Haiti were indistinguishable by all laboratory methods, revealing that the outbreak strain was V. cholerae serogroup O1, serotype Ogawa, biotype El Tor, and PulseNet PFGE pattern combination KZGN11.0092/KZGS12.0088. The strain possessed a cholera toxin variant that was first seen in cholera strains of the classical biotype. As of November 13, data indicated that a single strain caused illness among the 14 persons from Artibonite Department. If these isolates are representative of those currently circulating in Haiti, the findings suggest that V. cholerae was likely introduced into Haiti in one event. V. cholerae strains that are indistinguishable from the outbreak strain by all methods used have previously been found in countries in South Asia and elsewhere. PFGE analysis on isolates obtained from cholera patients who became ill in other departments in Haiti is ongoing.

Whole genome sequence (WGS) analysis of three isolates from the current outbreak, and other V. cholerae strains is under way. Comparative WGS analysis is the ultimate discriminatory subtyping tool because it detects any and all genetic difference among isolates. Limited WGS data are available currently for V. cholerae. Comprehensive libraries of V. cholerae genomes from epidemiologically or geographically related and unrelated isolates are needed before the sequence data of the Haiti outbreak strain can be interpreted in the proper epidemiologic context.

A representative outbreak isolate has been deposited into the American Type Culture Collection (ATCC) under the strain number BAA- 2163, and the draft genome sequences of the three isolates have been deposited into the GenBank database under the accession numbers AELH00000000, AELI00000000, and AELJ00000000.* Genome sequences will be updated in this database as they become available. Availability of an isolate and WGS of the Haiti outbreak strain as a public resource should facilitate rapid additional characterization by the global scientific community.

Initial antimicrobial susceptibility testing performed at LNSP indicated that all isolates were susceptible to tetracycline (a proxy for doxycycline) but resistant to sulfisoxazole and nalidixic acid. Additional antimicrobial susceptibility testing at CDC on 14 isolates determined that these isolates demonstrated susceptibility to azithromycin, reduced susceptibility to ciprofloxacin, and resistance to furazolidone. Antimicrobial treatment is recommended for severe cholera cases only. Recommended regimens include single-dose doxycycline (for nonpregnant adults and children), azithromycin (for pregnant women and all others), and other antimicrobial agents...

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5945a1.htm?s_cid=mm5945a1_e