Oral Cholera Vaccine Delivery in Rural Bangladesh
Oral Cholera Vaccine Delivery in Rural Bangladesh
Background:

 Vibrio cholerae is one of the major causes of severe diarrheal disease in Bangladesh. It is
 estimated that there are about 450,000 cholera cases each year in Bangladesh. Cholera is
 prevalent in both urban and rural settings in the country. Policy decisions about how best a
 new public health tool can be incorporated into the system requires evidence. Investigators
 have recently carried out a feasibility study of oral cholera vaccine in urban Dhaka in
 Mirpur (Protocol #10061). However, whether a similar system can also be utilized in a rural
 area in Bangladesh needs to be studied.

 The hospital disease surveillance data from International Centre for Diarrhoeal Disease
 Research, Bangladesh (icddr,b) reveals a substantial burden of cholera from Keraniganj
 upazila. Investigators propose a feasibility study of oral cholera vaccination by using the
 existing national immunization service delivery mechanism in Keraniganj. This study will help
 to provide evidence for the policy makers in introducing oral cholera vaccine in preventing
 cholera in high risk rural areas in Bangladesh.

 Hypothesis:

 That icddr,b in collaboration with the Government of Bangladesh will be able to implement an
 oral cholera vaccine program that;

 1. reaches residents of rural union of Keraniganj

 2. reduces the incidence of diarrhea due to Vibrio cholerae

 Objectives:

 1. Carry out cholera vaccination in one rural union in Keraniganj.

 2. Evaluate the impact of vaccination in reducing cholera in the study area

 Methods:

 Two unions in Keraniganj will be selected; around 30,000 individuals in one union will be
 vaccinated and impact evaluated by comparison with another similar union. After vaccination,
 passive cholera surveillance at the Upazila hospital will be conducted for two years on the
 patients from the two unions.

 Outcome measures/variables:

 Cholera vaccination programme will be assessed by the number of doses administered, drop-out
 rates between the two rounds, the proportion of vaccine wastage, and the vaccine coverage.

 Proportion of diarrheal hospitalizations that are due to V. cholerae O1 between the
 vaccinated and non vaccinated union will be calculated and compared to assess the impact of
 intervention.
This study in two selected rural cholera endemic unions in Keraniganj Upazila near Dhaka city
 will continue for two and half years. The study has two major components- 1. Feasibility of
 intervention with oral cholera vaccine in one union; and, 2. Impact evaluation of the
 intervention through prospective passive surveillance for diarrheal patients coming from the
 two selected unions at the upazila health complex. For the cholera vaccination all male and
 non-pregnant female residents above one year age will be targeted for vaccination in the
 selected union. Investigators are excluding less than one year children and pregnant woman
 form vaccination. For the surveillance part a standardized questionnaire will be administered
 to all consented diarrheal patients or their guardians in order to obtain information on
 diarrhea, health and demographic issues. Stool samples will be co llected and tested for V.
 cholerae O1 and O139.

 Investigators, purposively, have selected Keraniganj Upazila of Dhaka as the study area due
 to high incidence of diarrhea and evidence of culture confirmed cholera and its close
 proximity to Dhaka. Based on the Keraniganj diarrheal disease report and evidence of cholera
 prevalence in icddr,b surveillance data, the Ruhitpur union with approximately thirty
 thousand population will be selected as our area for vaccination, the intervention union.

 To evaluate the effectiveness of intervention Investigators will include Basta union of
 Keraniganj as the non-intervention area. In selecting the two unions, to make them
 comparable, in addition to population size, evidence of diarrhea and cholera, Investigators
 have considered the closeness to the Upazila Health Complexes (UHC), presence of educational
 institutes and health facilities, literacy rates, land area, etc.

 Investigators will use the killed whole cell oral cholera vaccine, "Shanchol", manufactured
 by Shantha Biotechnics for the study. The vaccine is registered in India and is prequalified
 by WHO. In urban Mirpur area investigators have already successfully used more than 265,000
 doses of the same vaccine. Vaccines are stored in the EPI(Expanded program on immunization)
 cold room at 2-8 degree C. Based on available space in District and upazila cold stores,
 vaccines will be shifted from the EPI cold room facilities in Dhaka. Investigators will use
 the rural health facilities including community clinics as the vaccination site for
 vaccinating the catchment eligible targeted population. Investigators will use the existing
 EPI cold chain facilities at the Keraniganj Upazila health complex to deliver the vaccine in
 the selected union. During vaccination, vaccinators will gently shake the single dose vial
 well to disperse the suspension and then open it to feed its content to the recipient. Adults
 and older children can take the vaccine by themselves but vaccinators will feed the vaccine
 contents to younger children. Trained Community health care provider, Health Assistants and
 Family Welfare assistants of the community clinic area will act as vaccinators. There will be
 adequate training for all concerned prior to the vaccination programme.

 In addition, volunteers from the community will be recruited and trained to assist with the
 vaccination and social mobilization activities. Investigators will develop appropriate
 communication materials to inform the population about the cholera vaccination opportunity.
 Local health facilities, pharmacies and community residents will be involved to assist social
 mobilization of the population to attend vaccination sessions. Persons below one year of age
 and pregnant women will not receive the vaccine. People living in the adjacent unions will
 not be eligible to receive the vaccine, due to limited number of vaccines in hand.
 Investigators will have to clarify in a convincing way through the field workers, community
 volunteers/leaders and to the stakeholders that everyone cannot be given the intervention
 because of the targeted approach and unavailability of vaccine for all and because this study
 is only a feasibility study to test the vaccine delivery mechanism in a rural setting.

 All patients from the study area to the Keraniganj Upazila Health Complex (UHC) with
 diarrhoea will be included in cholera surveillance. All study participants will be encouraged
 to attend Upazila health complex for the treatment of diarrhoeal diseases at the initiation
 of the study and time to time will be reminded by the field workers. A patient who has in the
 last 24 hours three or more loose or liquid stool is defined as a case of diarrhea (13). The
 surveillance for cholera at the Upazila health complex will be carried out for two years. As
 the study is implementing passive surveillance in both the unions- intervention and control,
 to see the effectiveness of the intervention, the key element is to capture most of the cases
 coming from the two unions. To do so, the study will convey the messages to the people of the
 two unions to utilize the existing GoB(Government of Bangladesh) facility in the upazila
 health complex for diarrheal illness. Study will provide a card to the peoples in two unions
 which will contain such messages, while distributing the cards field workers will convey the
 messages and tell them to bring the cards for diarrheal illness at the Keraniganj UHC. The
 existing field health workers, workers in the health facilities (community clinics, health &
 family welfare center) will be encouraged to convey such messages and refer the diarrheal
 patients to the Keraniganj upazila health complex. The patients in the OPD(out patient
 department) and ORT(oral rehydration therapy) corners at the Keraniganj UHC will be included
 in the passive surveillance and other private clinics/hospital(if available and agrees) will
 also be taken under surveillance.

 Investigators will collect stool or rectal swab specimens from diarrheal patients coming from
 the study population for diarrheal diseases. Specimens will be evaluated for V. cholerae
 O1and O139 according to WHO/CDC guidelines at the icddr,b.
Inclusion Criteria:

 1. Apparently healthy residents

 2. Aged 1 year and above

 3. Non Pregnant women -

 Exclusion Criteria:

 1. Age less than 1 year

 2. Pregnant women -