Viewing Study NCT05996549



Ignite Creation Date: 2024-05-06 @ 7:24 PM
Last Modification Date: 2024-10-26 @ 3:06 PM
Study NCT ID: NCT05996549
Status: RECRUITING
Last Update Posted: 2023-08-18
First Post: 2023-07-26

Brief Title: Cost-effectiveness of the Influenza Vaccination
Sponsor: International Centre for Diarrhoeal Disease Research Bangladesh
Organization: International Centre for Diarrhoeal Disease Research Bangladesh

Study Overview

Official Title: Acceptability Cost-Effectiveness and Capacity of a Facility-Based Seasonal Influenza Vaccination A Study in Selected Hospitals of Bangladesh
Status: RECRUITING
Status Verified Date: 2023-07
Last Known Status: None
Delayed Posting: No
If Stopped, Why?: Not Stopped
Has Expanded Access: False
If Expanded Access, NCT#: N/A
Has Expanded Access, NCT# Status: N/A
Acronym: None
Brief Summary: Background In Bangladesh seasonal influenza imposes considerable health and economic burden particularly for those at high risk of severe disease To prevent influenza and lessen the economic burden despite the World Health Organizations WHO recommendation of seasonal influenza vaccination prioritizing high-risk groups many low-income countries including Bangladesh lack a national policyprogramme and relevant statistics on seasonal influenza vaccination

Objectives

1 To determine influenza vaccine acceptability health beliefs barriers and intention of receiving influenza vaccine among targeted high-risk populations
2 To determine the cost-effectiveness of a seasonal influenza vaccination targeting high-risk populations during visits to health facilities for routine care
3 To investigate the required capacity for a potential seasonal influenza vaccination programme targeting high-risk populations during their visits to health facilities for routine care

Methods The study will be conducted in three hospitals inpatient and outpatient departments with ongoing hospital-based influenza surveillance HBIS To meet objective 1 the investigators will collect quantitative data on participants acceptability health beliefs barriers and vaccination intentions using the health belief model HBM from patients meeting criteria for high-risk populations attending two public tertiary-level hospitals To meet objective 2 in one of the two hospitals the investigators will run an influenza vaccination campaign before the influenza season the vaccines will be in the southern hemisphere where the vaccine will be offered free of cost to high-risk patients and in the second hospital vaccination will not be offered Both the vaccinated and unvaccinated participants will then be followed-up for one year period once a month to record any influenza-like illness hospitalization and death Additional data for objective two on direct and indirect costs associated with influenza illness will be collected from patients with influenza-like illness ILI and severe acute respiratory infections SARI at one public and one private hospital To meet objective 3 the investigators will estimate the required number of influenza vaccines safe injections and total storage volume utilizing secondary data The investigators will use a deterministic Markov decision-analytic model to estimate the cost-effectiveness of facility-based vaccination in Bangladesh
Detailed Description: Background Globally seasonal influenza is a leading cause of morbidity and mortality with significant health and economic consequences According to the World Health Organization WHO influenza affects around one billion people each year with 3 to 5 million suffering from severe illness leading to 290000 to 650000 deaths each year The burden of influenza illness is significantly higher in low- and middle-income countries LMICs than in high-income countries HIC Pregnant women children under five years and adults with co-morbid conditions in LMICs are more likely to get severe influenza illness In a systematic review and meta-analysis of 27 studies found that elderly people were at higher risk of death and hospital admission during flu season That study also found that pregnant women and children were at higher risk of developing pneumonia and requiring hospital admission the adults with co-morbidity conditions were at risk of hospitalization and intensive care admission during flu seasons

In order to prevent influenza infection and lessen the severity of the illness in 2012 the WHO advised an annual influenza vaccine dosage for persons at high risk of acquiring a severe influenza illness Despite the WHO recommendation of seasonal influenza vaccination prioritizing high-risk groups 76 of the low-income countries including Bangladesh lack a national policyprogramme on seasonal influenza targeting high-risk groups Also the lack of context-specific knowledge on the economic burden of influenza vaccines on high-risk groups lack of medical socio-behavioral patterns and socio-economic consequences of influenza have been identified as challenges for promoting influenza vaccinations in LMICs

In Bangladesh around 25 million people of all ages sought outpatient treatment for influenza where the yearly direct cost of influenza-associated outpatient visits was US 108 million Moreover approximately 30592 laboratory-confirmed influenza patients of all ages were hospitalized each year with an estimated annual influenza-associated hospitalization cost of US 14 million Influenza vaccines are the most reliable method for preventing influenza infection But unfortunately Bangladesh does not have a national influenza vaccination program among the WHO-recommended high-risk population The Ministry of Health and Family Welfare MoHFW Government of the Peoples Republic of Bangladesh only offers influenza vaccination to all Hajj pilgrims free of cost as part of the mandatory requirement for all Hajj pilgrims by the Saudi Government However there is a lack of information to drive the MoHFW policy on influenza vaccinations in high-risk populations

For reducing the influenza disease burden particularly among high-risk populations influenza vaccination has been proven to be the most effective and cost-effective approach Immune responses elicited by influenza vaccines are generally strain-specific Antibody against one influenza virus type or subtype generally confers limited or no protection against another type or subtype nor does it typically confer protection against antigenic variants of the same virus that arise by antigenic drift However among adults vaccination can cause a back boost of antibody titers against influenza A viruses that have been encountered previously either by vaccination or natural infection Due to antigenic drift and shift influenza vaccines are taken annually with an efficacy between 40-60 varies widely by setting and by influenza seasons In addition a systematic review of 118 studies on the cost-effectiveness of influenza vaccination revealed that 22 of the 118 studies showed influenza vaccination to be cost-saving The study reported cost-effectiveness ratios of 10000outcome in 13 studies 10000 to 50000 in 13 studies and 50000 in 3 studies Despite the fact that influenza vaccination was cost-effective the cost-effectiveness parameters may not be applicable for all countries contexts because of the differences in influenza disease profile influenza vaccination unit costs and health system delivery mechanisms Hence country-specific estimates are essential for the optimal allocation of scarce resources

The investigators extensively searched influenza vaccination cost-effectiveness studies targeting high-risk populations in Bangladesh But to date there is scarce evidence in Bangladesh to inform policymakers about the acceptability cost-effectiveness and required capacity of influenza vaccination among the WHO-defined high-risk group population Therefore the investigators propose to generate preliminary data on high-risk groups health beliefs barriers and intent to receive the influenza vaccine The investigators will also generate preliminary data on the acceptability cost-effectiveness and required capacity for a facility-based influenza vaccination program to support policy decisions on influenza vaccination in Bangladesh among the high-risk population

Research Design and Methods

Study design

The investigators have been conducting our study leveraging hospital-based influenza surveillance HBIS ongoing in nine tertiary-level hospitals across Bangladesh The study design is quasi-experimental

Study sites

The investigators have chosen study hospitals considering several factors Firstly the investigators will conduct this study leveraging hospital-based influenza surveillance The investigators have chosen Rajshahi medical college hospital and Khulna medical college hospital for study activities related to objectives 1 2 To meet objectives 1 2 as hospital-based influenza surveillance identifies SARI ILI or influenza-positive patients it will be helpful to enroll SARI and ILI patients including those with laboratory-confirmed influenza to collect data on the costs of influenza illness This approach will save funds for influenza testing not allocated in the current study budget Secondly to assess the outcome of influenza vaccination the investigators plan to enroll patients from public tertiary-level hospitals one treatmentvaccinated and the other control hospital to minimize baseline differences between the treatmentvaccinated and control arm Thirdly the investigators have chosen Ragib-Rabeya Medical College Hospital to track public and private healthcare facility cost differences while estimating the costs of influenza illness

Study sites for Objective 1

The investigators have conducted an HBM survey in two conveniently selected hospitals

1 Rajshahi Medical College Hospital Rajshahi
2 Khulna Medical College Hospital Khulna

Study sites for Objective 2

For objective two the investigators are collecting data on the health outcome of vaccination and the cost associated with influenza illness Data on health outcomes have been collected from two public tertiary-level hospitals same sites for objective 1 The cost associated with influenza illness data has been collected from one public and one private hospital

Health outcomes of vaccination

1 Rajshahi Medical College Hospital Rajshahi
2 Khulna Medical College Hospital Khulna

Cost associated with influenza illness

1 Rajshahi Medical College Hospital Rajshahi
2 Jalalabad Ragib-Rabeya Medical College Hospital Sylhet

Study sites for objectives 3

The investigators will utilize secondary data to estimate the required capacity for seasonal influenza vaccination at three hospital catchment areas

Study population

Study participants are the WHO-defined four different high-risk groups children six months to 8 years pregnant women elderly 60 years and adults with chronic diseases

Data collection to assess health beliefs barriers and intention to receive an influenza vaccine objective 1

The investigators have collected data on acceptability health beliefs obstacles and current intentions to receive the vaccine from enrolled participants The investigators have captured these data using the health belief model HBM The questionnaire has been developed using an existing literature review The investigators have included items to assess five theoretical constructs of HBM based on reviewing relevant literature including high-risk individuals perceived susceptibility to disease perceived severity of influenza perceived benefits of the vaccine perceived barriers to the vaccine cues to action and self-efficacy The investigators have conducted face-to-face interviews for the data collection

Data collection to determine the cost-effectiveness of seasonal influenza vaccination objective 2

Health outcomes of vaccination

Vaccination campaign

To record health outcomes after influenza vaccination objective 2 in one of the two study hospitals the investigators have been running an influenza vaccination campaign before the influenza season where the vaccine has been offering free of cost to high-risk patients Inpatients and outpatients of all departments are informed about the ongoing immunization campaign Eligible patients have been offered to take the vaccine during the vaccination campaign Benefits significance adverse effects and how to manage them have been explained to the patients

In the second hospital the investigators are enrolling participants meeting the high-risk group individual criteria However no vaccination campaign will be conducted The investigators have named this group as an unvaccinated cohort Control Arm

Follow-up of vaccinated and unvaccinated participants

The investigators will follow up with vaccinated and unvaccinated study participants bi-weekly through mobile phones for the entire influenza season During the follow-up data will be recorded on health outcomes including respiratory symptoms influenza-like illness hospitalization and death

Cost associated with influenza illness

For collecting data on costs associated with influenza illness the investigators will enroll high-risk individuals visiting study hospitals who will meet the SARI and ILI case definitions

Severe acute respiratory illness SARI For patients of all ages a history of or measured temperature 380C and cough began during the last ten days and necessitated hospitalization

Influenza-like illness ILI Measured fever above 380C with cough having an onset within the last ten days The investigators will collect data on the enrolled participants direct and indirect medical costs associated with influenza illness episodes Cost breakdowns for influenza illness episodes are provided below

Direct medical and non-medical costs for influenza illness episodes

Direct costs will consist of health care provider fees hospital registration fees bed rental prescriptions laboratory testing transportation and mobile phone calls The investigators will also record informal payments made during hospital visits Costs for all medications laboratory tests registration and room rental will also be included The investigators will also collect payment if patients visit a pharmacy or other clinics prior to hospitalization The non-medical expenses for patients or caregivers include food lodging and transportation The investigators will collect data directly from patients and their families Members of the participants family or the participants themselves will be able to determine which drugs and tests they received for free hospital subsidized cost and which they paid for out of pocket out-of-pocket

Productivity loss or indirect cost

The investigators will also collect data on participants or caregivers or family members lost productivity and indirect costs incurred during illness The investigators will record the number of workdays missed by participants family members participants themselves and caregivers due to sickness or family caregiving The investigators will exclude weekends and national holidays from our calculation Every day missed due to illness or while caring for sick family members will be considered a lost workday for hourly-wage workers and housewives The investigators will not consider the days missed due to decreased activity such as a half-day of work school absences or influenza-related fatalities

Costs of durable equipment and other fixed costs

The investigators are collecting the primary data on the costs of the supplies and materials consumed not purchased and stored at the hospitals involved in diagnosing and treating influenza illness by department ward and service for example per unit cost and required units for blood drawn x-ray C-reactive protein complete blood count blood culture test widal test etc The investigators are also collecting data related to health facility operating hours working hours by ward and department the ticket price of different departments inpatients or outpatients units and bed rent

Collating secondary data for objective 2

Disability-adjusted life year DALY

The investigators will collect secondary data on disability-adjusted life years DALY from the WHO global health estimation The investigators will utilize age and symptoms-specific DALY estimates to determine the DALY associated with influenza-related health outcomes Though QALY is widely used for hospital patients due to the unavailability of publicly available QALY data related to influenza or influenza-like illnesses for LMICs the investigators have decided to use the WHO-estimated publicly available DALY estimates for the study

Data sources for estimating influenza-associated disease burden

To estimate the key parameters of influenza-associated disease burden such as the number of outpatients visits hospitalization and deaths the investigators will collect data from the following secondary sources Assumptions and data sources by each target group are indicated below

Target Study Group 1 Children 6 months to 8 years

Assumption and data sources Two doses will be delivered each four weeks apart Data on the total number of 5 years children will be adopted from the Statistical Yearbook of Bangladesh 2020 Monthly the number of children 8 years visited hospitals will be collected from respected hospitals or respective District Civil Surgeon Office

Target Study Group 2 Pregnant women

Assumption and data sources One dose to all pregnant women any trimesters The crude birth rate is assumed to be 219 BDHS 2017-18 Influenza vaccines were distributed evenly across the childbearing years 15 through 49 Data on the total number of women of childbearing age 15-49 years will be collected from the Statistical Yearbook of Bangladesh 2020 Monthly pregnant women who visited hospitals will be collected from respective hospitals or respective District Civil Surgeon Office

Target Study Group 3 Elderly 60 years

Assumption and data sources One dose for all persons aged 60 years and older Population data from the Statistical Yearbook of Bangladesh 2020 Monthly the total number of 60 years aged patients visited hospitals will be collected from respected hospitals or respective District Civil Surgeon Office

Target Study Group 4 Adults with chronic diseases

Assumption and data sources One dose for all persons with chronic disease The investigators will use the prevalence of having any chronic illness from the Bangladesh Household Income and Expenditure Survey HIES 2010 Then the total number of persons with any chronic illness will be estimated using data from the Statistical Yearbook of Bangladesh 2020 Monthly patients with chronic diseases visited hospitals will be collected from respected hospitals or respective District Civil Surgeon Office

Vaccine coverage

The investigators will use secondary data for the input parameters relating to seasonal influenza vaccination coverage in Bangladesh The investigators will extract information on hospitals catchment areas population size from the Statistical Yearbook of Bangladesh 2020

Vaccine adverse event costs

Vaccine adverse event costs will be estimated for each targeted risk group Using primary and secondary data the investigators will estimate the costs of influenza vaccination adverse events The investigators will use secondary data to estimate influenza vaccination rates and adverse events whereas primary data will be used to determine the cost

Data collection to estimate the required capacity of a hospital-based influenza vaccination programme objective 3

The investigators will collect secondary data to calculate the requirements capacity at each hospital Secondary data will be collected about the population size of the targeted risk group in the hospitals catchment area the number of doses required for vaccinating each high-risk individual the number of doses per vial packed volume doses syringes and safety box

Sample Size Calculation

The sample size for vaccine acceptability Primary outcome of this study for vaccine acceptability is the intention to receive the influenza vaccine According to high-risk group-specific health belief model studies from neighboring countries 91 of elderly people 88 of adults with chronic illness 763 of pregnant women and 624 of parents with six-month-to-three-year-olds intended to get the influenza vaccine The investigators expect a similar positive intention to receive the influenza vaccine ranging from 62 to 91 for our target study population The investigators utilize a 5 significance level 80 power design effect of 12 and 10 non-response to estimate the sample size The estimated sample size by the high-risk group for vaccine acceptability objective 1 is given below

The sample size for children six months to 8 years 659 The sample size for pregnant women 495 The sample size for Elderly 60 years 330 The sample size for adults with chronic diseases 425

The sample size for vaccine effectiveness Next outcome for health outcome for vaccination is vaccine efficacy against influenza-like illness among high-risk group populations Studies from neighboring countries found that ILI symptoms were 1530 of children 3123 of adults with chronic illness 1097 of pregnant women and 20 of the elderly A systematic review of seasonal influenza vaccine policy use and efficacy also revealed that pooled vaccine efficacy for high-risk groups in the tropics and subtropics ranged from 48 to 88 The investigators expect a similar vaccine efficacy between 50-81 for our studys targeted high-risk group population The investigators also assume a 5 significance level 80 power design effect of 12 and 10 non-response to estimate the sample size The high-risk groups estimated sample size for vaccine effectiveness is given below

The sample size for children six months to 8 years 465 The sample size for pregnant women 756 The sample size for Elderly 60 years 736 The sample size for adults with chronic diseases 610

The sample size for the cost-components survey Another outcome for costs-components is the total influenza-associated illness costs among high-risk group populations A study in Bangladesh on the economic evaluation of influenza-associated disease estimated that the total direct cost of influenza-associated illness was 7614 TK for children under five years followed by 20808Tk for pregnant women 13761 TK for elderly and 8222 TK for adults with chronic diseases The investigators expect a similar total direct cost of influenza-associated illness of 7614Tk-20808Tk for our studys targeted high-risk group population Other than that the investigators utilize a 5 significance level 80 power design effect of 12 and 10 non-response to estimate the sample size The high-risk groups estimated sample size for the cost-components survey is given below

The sample size for children six months to 8 years 60 The sample size for pregnant women 39 The sample size for the Elderly 60 years 56 The sample size for adults with chronic diseases 31

Data Analysis

The investigators will summarize all the data by descriptive statistics tools including frequency percentage mean median standard deviation SD and interquartile range 25th percentile - 75th percentile

Objective specific data analysis plan is as follows

Data analysis on the propensity to vaccine using results from the HBM survey Objective 1

In each of the five HBM constructs the investigators will use factor analysis using the principal axis factor technique and varimax rotation to find latent variables and minimize the number of independent variables The Kaiser-Meyer-Olkin test will be used to determine sample adequacy The investigators will also use Cronbachs alpha to test the internal consistency of survey items

Data analysis for cost-effectiveness analysis Objective 2

Vaccine efficacy estimation

The investigators will utilize Poisson regression to obtain rate ratios RRs for vaccinated and unvaccinated individuals against influenza In the final model the investigators will include all the variables that will be found to have a confounding effect or found to be significant at a 5 level of significance The investigators will calculate vaccine effectiveness with 95 CI for each risk group 1 - RR 100

Cost-effectiveness estimation

To estimate the pilot influenza vaccination cost-effectiveness targeted for the high-risk group the investigators will use the built-in formulas of the CETSIV tool Besides the investigators will recheck the outputs by developing a deterministic Markov decision-analytic model to simulate outcomes under alternative assumptions of input parameters The investigators will conduct a probabilistic sensitivity analysis PSA to see how parameter estimation precision uncertainty affects the models outcome If ICER is below less than three times the gross domestic product GDP per capita the investigators will consider the vaccination as cost-effective as per the WHO standard

Vaccination cost estimation The financial and economic costs of the vaccination programme will be collected using the WHO seasonal influenza immunization costing tool SIICT The WHO seasonal influenza immunization costing tool SIICT was updated in 2020 and was newly named The WHO Flutool Plus The investigators will use the newly developed WHO Flutool Plus and customize all the components for the facility-based vaccination However the investigators assume a discount rate of 5 Bangladesh Bank Dollars exchange rate of 105 to 110 TK will be used to represent the findings at all estimates According to the Bangladesh Bank the inflation rate will also be adjusted with all of our estimates

Data analysis to calculate required capacity Objective 3

The investigators will estimate annual influenza vaccine dose and safe-injection equipment requirements for the target hospitals adopting the WHO guidelines to calculate vaccine volumes and cold chain capacity The investigators will also estimate the required storage volume shortage volume for the vaccine and safe injection

Study Oversight

Has Oversight DMC: None
Is a FDA Regulated Drug?: False
Is a FDA Regulated Device?: False
Is an Unapproved Device?: None
Is a PPSD?: None
Is a US Export?: None
Is an FDA AA801 Violation?: None