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ORIGINAL ARTICLE
Year : 2018  |  Volume : 62  |  Issue : 4  |  Page : 253-258  

Vaccine hesitancy for childhood vaccinations in slum areas of Siliguri, India


1 Assistant Professor of Epidemiology, Institute of Public Health, Kalyani, Nadia, West Bengal, India
2 Assistant Professor, Department of Community Medicine, North Bengal Medical College and Hospital, Siliguri, West Bengal, India
3 Professor and Head, Department of Community Medicine, North Bengal Medical College and Hospital, Siliguri, West Bengal, India

Date of Web Publication11-Dec-2018

Correspondence Address:
Dr. Sharmistha Bhattacherjee
Department of Community Medicine, North Bengal Medical College and Hospital, Siliguri - 734 012, West Bengal
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijph.IJPH_397_17

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   Abstract 


Background: Despite evidence regarding the beneficial effects of vaccines, vaccination uptake has not been up to the mark across the globe in various sociocultural and sociodemographic groups. Logistics and workforce have been issues of concern to public health managers, but the latent issue of vaccine hesitancy leading to vaccine delays and refusals has not been widely addressed particularly in the Indian context. Objectives: The present study was conducted to find out the proportion and factors contributing to vaccine hesitancy for childhood vaccinations in slums of Siliguri, India. Methods: A cross-sectional study was carried out among 194, 0–59 months' children residing in slums of Siliguri in 2016. Data were collected at the household with interviews of mothers/primary caregivers using a predesigned pretested interview schedule developed based on the validated version of vaccine hesitancy survey questionnaire originally developed by the World Health Organization Strategic Advisory Group of Experts working group on vaccine hesitancy. Associations were analyzed using logistic regression. Results: Majority 161 (83%) of the families were vaccine-hesitant and only 33 (17%) were not hesitant. Nuclear families and mothers of lower educational status had significantly higher odds of vaccine hesitancy. Reluctance to vaccinate (26.1%) and to be unaware/having no reliable information (20.5%) were the major reasons cited for vaccine hesitancy. Conclusion: Most of the families of the children were vaccine-hesitant in the area. Uniformity in schedules in different health facilities in slum areas, appropriate antenatal information, and counseling regarding childhood vaccinations, widespread awareness, and improving mothers' education can address the issue of vaccine hesitancy.

Keywords: Household, India, public health, slums, vaccination


How to cite this article:
Dasgupta P, Bhattacherjee S, Mukherjee A, Dasgupta S. Vaccine hesitancy for childhood vaccinations in slum areas of Siliguri, India. Indian J Public Health 2018;62:253-8

How to cite this URL:
Dasgupta P, Bhattacherjee S, Mukherjee A, Dasgupta S. Vaccine hesitancy for childhood vaccinations in slum areas of Siliguri, India. Indian J Public Health [serial online] 2018 [cited 2019 Mar 19];62:253-8. Available from: http://www.ijph.in/text.asp?2018/62/4/253/247231




   Introduction Top


Vaccines are regarded as one of the most important public health measures to combat both communicable as well as noncommunicable diseases. However, over the years, vaccine hesitancy has become a growing focus of attention and concern.[1],[2],[3] The World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE) on immunization has defined vaccine hesitancy as “delay in acceptance or refusal of vaccination despite the availability of vaccination services.” Vaccine hesitancy is complex and context specific, varying across time, place, and vaccines. Vaccine hesitancy occurs along a continuum between full acceptance and outright refusal of all vaccines, i.e., when there is acceptance of some and delay or refusal of some of the recommended vaccines. It is influenced by factors such as complacency, convenience, and confidence.[4]

Vaccine hesitancy, thus, risks the public health consequences of vaccine-preventable disease outbreaks. While addressing vaccine hesitancy within a country or subgroup, an in-depth understanding of magnitude and setting of the problem is required.[5]

Countries should incorporate a plan to measure and address vaccine hesitancy into their country's immunization program as part of good program practices. Immunization programs of countries must fit their setting and resources to support vaccine uptake. Education and training of health-care workers need to be undertaken to address vaccine-hesitant behaviors among them.[5]

The childhood vaccination coverage of urban areas (76.2%) in West Bengal is less than total (79.5%) and rural (80.8%) coverage according to DLHS-4.[6] Logistics and workforce for immunization have been issues of concern to public health managers.[7],[8] However, the latent issue of vaccine hesitancy has not been widely addressed in the Indian context. Exploring this aspect of vaccination will definitely help our policymakers to undertake appropriate measures to improve vaccine acceptance, coverage, and reach desired national targets.

The present study was conducted with the objective of finding out the proportion and factors contributing to vaccine hesitancy for childhood vaccinations in slum areas of Siliguri city, West Bengal.


   Materials and Methods Top


A community-based study with cross-sectional design was conducted in the slums of Siliguri city, India, from March to July 2016. The city has a total of 47 wards and 154 slums with a total population of 509,709 as per census 2011.[9]

Study subjects

Children aged 0–59 months, whose family resides in the study area for the past 12 months, were the primary study subjects. Those without immunization cards were excluded from the study.

Sampling

Owing to the scarcity of studies in India showing vaccine hesitancy in the slum areas, the anticipated proportion of vaccine hesitancy was taken as 50% to generate maximum possible sample size. Considering 95% confidence level, 10% absolute precision, design effect of 2, nonresponse rate of 10%, the sample size was calculated as 211.[10]

Thirty slums or “clusters” were identified using principles of cluster sampling from 154 slums. From each selected cluster equal number, i.e., seven children were selected.

Tools and techniques

Data were collected by interviewing the mothers/primary caregivers using a predesigned schedule and reviewing immunization cards of the children. In addition to the questions on sociodemographic characteristics of the family and immunization status-related variables, the schedule comprised questions based on vaccine hesitancy survey questions: Version 1.0 developed by the SAGE Working Group on vaccine hesitancy.[11]

Before starting the present study, the schedule was validated in local vernacular by initial translation, back translation, and retranslation, followed by a pilot study in urban field practice area of North Bengal Medical College, Darjeeling.

Variables

Sociodemographic variables included age of the child, gender, birth order, education of mother, type of family, and socioeconomic status (SES) using modified BG Prasad scale.[12]

Immunization status related variables included, “vaccine delay” and “vaccine refusal/reluctance” for any dose. Only the vaccines given under the National Immunization Schedule of India[13] and introduced in the study area at the time of data collection, were considered for vaccine delay or hesitancy. These vaccines are Bacille Calmette–Guérin (BCG), Hepatitis-B (0, 1st, 2nd, 3rd dose); Oral-Polio-Vaccine (OPV) (0, 1st, 2nd, 3rd and Booster dose); Diphtheria-Pertussis-Tetanus (DPT) (1st, 2nd, 3rd and Booster dose); Pentavalent (1st, 2nd, 3rd dose) constituting of  Haemophilus influenzae Scientific Name Search pe b, DPT, and Hepatitis-B; measles (1st, 2nd dose); and Japanese-encephalitis (JE) (1st, 2nd dose). Since Vitamin A is a nutritional supplement, it was not included in the present study.

Vaccine “delay” was operationally defined as any dose received beyond 24 h for birth dose of Hepatitis-B. However, any doses received beyond 14 days of expected date were considered as “delay” for other vaccines.[14] Expected date for a particular dose of vaccine was calculated as per the date of birth recorded in the immunization cards. “Vaccine refusal/reluctance” was defined as refusal of or reluctance to any dose of a particular vaccine, resulting in the child not receiving the dose despite the availability of vaccination services.

The main outcome variable was “vaccine hesitancy.” Vaccine hesitancy was considered to be present in those families who refused, were reluctant or delayed any of the recommended vaccine dose of their child, as per his/her age. Vaccine hesitancy was considered to be absent in those families, where the selected child, received all the recommended vaccines within stipulated time as operationally defined.

Open-ended questions were also asked the respondents regarding the reason for vaccine hesitancy. The responses were then grouped into discrete nonoverlapping categories. The responses to vaccine hesitancy attitude statements regarding childhood vaccinations ranged from 1 (strongly disagree) to 5 (strongly agree).

Data collection

After obtaining clearance from Institutional Ethics Committee, permission and cooperation were sought from the local authorities. In a cluster, from a known landmark, in a random direction seven consecutive households (having 0– 59-month-old aged child) were visited with the help of local health workers. On reaching the selected household, the family was explained about the purpose of the study and assured about confidentiality and anonymity of the information and mother/primary caregiver of the child was interviewed. In case of more than one children of the required age group in the same household, only one was included randomly in the study. In case of the absence of mother/primary caregiver, refusal to respond, or if the immunization cards were incomplete etc., it was considered as nonresponder.

Data analysis

Univariate and multivariate analysis was done using binary logistic regression to find predictors of vaccine hesitancy among the families. The crude odds ratio (OR) was calculated for each of the predictor variables. Adjusted OR (AOR) for vaccine hesitancy status was calculated after adjusting for background predictor variables. The differences in attitude scores between the vaccine-hesitant caregivers from those who were not vaccine-hesitant were assessed using Mann–Whitney U-test.

Further, for each child, vaccine-specific events were calculated based on his/her age and those which were available at the respective facilities. The proportion of delay, refusal/reluctance, and no delay was thus calculated for individual vaccines based on the total vaccine-specific events. The analysis was performed with IBM Statistical Package for the Social Sciences (SPSS, Armonk, NY: IBM Corp) version 20. P < 0.05 was considered statistically significant.


   Results Top


Of 210 families approached for the study, 194 participated in the study. In seven cases, mother/primary caregiver of the child was absent during visit, four cases immunization cards were incomplete, and five of the families refused to respond (response rate 92.4%).

The mean age of the children was 27.8 ± 15.9 months. Majority of the study subjects were females (58.8%), first birth order (59.3%), belonging to nuclear families (51.0%), and lower socioeconomic status (60.3%). About 73.7% of the mothers had ≥5 years of schooling [Table 1].
Table 1: Predictors of vaccine hesitancy (n=194)

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Vaccine hesitancy was present among 161 (83%) families. Majority (73.2%) of caregivers believed that vaccines can protect children from serious diseases and about 152 (78.4%) believed that most parents have their children vaccinated with all the recommended vaccines. Although all the children had institutional deliveries, major delay was seen for BCG and OPV-0 and reluctance for Hepatitis-B-birth dose. Delay was more common for the primary doses than for the booster doses and measles. However, refusal/reluctance was seen for nearly half of the JE doses [Table 2].
Table 2: Status of vaccination and vaccine hesitancy among beneficiaries

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When asked about the reasons for vaccine hesitancy, most commonly cited was reluctance to vaccinate (26.1%). About 33 (20.5%) reported to be unaware or confused of when and where to vaccinate; not explained properly by health care providers regarding dates and the vaccines and no reliable information. In other cases (18.0%), the child was sick or irritable [Table 3].
Table 3: Causes of vaccine hesitancy (n=161)#

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Nuclear families (AOR; 95% confidence interval [CI]: 1 [referent] vs. 0.414; 0.178, 0.962) and <5 years schooling of mother (AOR; 95% CI: 1 [referent] vs. 0.301; 0.095, 0.957) had significantly higher odds of vaccine hesitancy. The odds of vaccine hesitancy were higher among SES Class I, II and male child and child of second or higher birth order. The logistic regression model was statistically significant, χ2 = −12.9; P < 0.05. After controlling for predictors, the model explained between 6.5% (Cox and Snell R2) and 10.8% (Nagelkerke R2) of the variance in vaccine hesitancy; it correctly classified 83.0% of cases [Table 1].

There was a significant difference in opinion among vaccine-hesitant mothers/caregivers, and those who were not vaccine-hesitant regarding statements childhood vaccines are important for child's health and getting vaccinated is a good way to protect children from disease, and that new vaccines carry more risks than older vaccines [Table 4].
Table 4: Mothers/caregivers' opinion toward childhood vaccinations (n=194)

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   Discussion Top


Parenteral attitudes and behaviors regarding vaccination fall into a spectrum comprised five unfixed groups, unquestioning acceptance, cautious acceptance, hesitance, late or selective vaccinator, and refusal of all vaccines.[15] Vaccine hesitancy in the present study has adopted the WHO definition which describes a continuum between unquestioning acceptance and refusal of all vaccines.[3]

Proportion of mothers/caregivers with vaccine hesitancy

The increase in full immunization coverage in West Bengal from 64.3% in 2005–2006 to 84.4% in 2015–2016[16] reflect only the gross coverage of vaccines, undermining the timeliness, hesitance for one or more vaccines which is an important aspect of the quality of immunization.

Although most of the caregivers in the present study were convinced of the role of vaccines to protect children and reported that most would like to have their children vaccinated with all the vaccines, a deeper exploration shows that only 17% had actually gone for all recommended doses on time. Barman and Dutta[17] found month-specific immunization coverage to be 16.4% in West Bengal, despite the picture of high non-month specific full immunization coverage of 75.9%. Clark and Sanderson[18] have found that there is wide variation in timeliness of vaccine coverage within and between 45 low- and middle-income countries.

Host/parental-specific factors

A significant association was found between nuclear family and vaccine hesitancy. In case the mother is the only caregiver, it results in delays, reluctance to take for vaccination due to household or other job. Often the problem is aggravated if the mother is sick, pregnant or she has to take care of other children. In traditional settings in India, the joint family structure has an added advantage of additional caregivers, where chances of getting timely vaccinated increase due to other parents of the household taking care, even if the mother is working.

Higher educational status of mothers has been associated with better immunization coverage in previous studies conducted in India[19],[20] and neighboring countries.[21] Educated mothers are more likely to remember dates, understand the importance of timely vaccination and interact more freely with health workers.

In the present study, higher SES showed a higher likelihood of vaccine hesitancy in contradiction to observations by previous authors.[17],[20] Vaccines are supplied free of costs in India in all government facilities. In the present study, parents who are economically better off, however, visit private facilities such as pediatricians' clinics where they must pay for vaccines as well as the services. If on the scheduled day or week, there is not enough money, they tend to be vaccine complacent[4] and delay or miss doses of costly vaccines such as pentavalent vaccine.

Among the characteristics of children, the gender of the child and birth order were not significant predictors for vaccine hesitancy in the present study. Barman and Dutta[17] support our observation. Although statistically not significant, the proportion of vaccine hesitancy in case of male child was marginally higher than girl child. This contradicts findings from some of earlier studies.[22],[23]

Agent/vaccine specific factors

Beneficiaries in the study area avail vaccination services from different facilities ranging from the nearby medical college, district hospital, municipal corporation funded clubs, subcenters, and private practitioners. Barring a few, the birth doses are either not given from the same facility or a few of recommended vaccines are given. There might be confusion among the caregivers where to vaccinate the child resulting in their delay like going for vaccination at a date when it has crossed the recommended period. In a study conducted by Patel and Pandit[24] in Gujarat, about 19.8% of infants received their first dose of vaccine after 2½ months of age.

Information regarding vaccines is often not properly disseminated resulting in apprehension and fear about newer vaccines. This might have refrained the families from getting the children vaccinated during the initial JE campaign in 2013. Freed et al.[25] reported more than half of the parents to be concerned regarding serious adverse reactions and question the safety of newer vaccines. In a study by Gust et al.[26] largest proportion of parents who changed their minds of delaying or not getting vaccinated gave “information or assurance from health care provider” as the main reason.

Environmental/external factors

Reluctance to vaccinate the child was the primary cause of vaccine hesitancy in the present study. Injectable vaccination at quick succession (6, 10, and 14 weeks) makes the child irritable-making the caregivers more reluctant. For the booster doses and measles, on the other hand, there is a greater time span of 9–12 months and 16–24 months. Lack of awareness, forgetfulness, laziness was reasons cited in previous studies in India.[27],[28],[29] Lack of trust in service providers was another reason cited by the respondents. This corroborates with the finding that a higher proportion of families who get their child vaccinated follow instructions of their doctors and health-care providers.

The inherent migratory and temporary nature of the slum population makes delay and hesitancy even more prominent. This can be deduced from the fact that about 8.7% of caregivers reported being away from home as the reason for hesitancy. The social behavior of mothers frequently traveling between husband's home and father's home during postnatal period is a major obstacle. Previous studies[24] support this observation. It is likely that mothers staying at father's home will miss reminders from the health workers who only register deliveries of daughters-in-law in the family to avoid duplication of birth registration.

The study was first of its kind to be conducted in the area. Mothers/caregivers' responses regarding vaccine hesitancy were corroborated with appropriate records. Open-ended questions complemented the data from structured questions for in-depth insight regarding the issue. Apart from inherent limitations of cross-sectional study, vaccine-specific causes of hesitancy could not be elicited properly because of likely incorporation of recall bias.


   Conclusion Top


Although national surveys have revealed improved immunization coverage in the area, most of the families of the children in the study were vaccine-hesitant; hinting toward gross quality underperformance. The multiplicity of service providing facilities lacking uniformity, slum population characteristics, poor spread of information, and long immunization schedule in repeated successions make the caregivers vaccine-hesitant.

District officials should ensure implementation of recommended national immunization schedule by proper dissemination of message and monitoring. Even if there is a change of facilities, service providers must ensure timely completion of remaining doses. In case of institutional deliveries, all health facilities, even if nongovernmental, should provide birth doses and inform mothers regarding subsequent doses. Mobile-based vaccine reminders can be widely used to address delays. Intricate issues of lack of trust, motivation to vaccinate need to be addressed by widespread awareness in slums where health access, in general, is poor.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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