Polio vaccine hesitancy in the networks and neighborhoods of Malegaon, India

doi:10.1016/j.socscimed.2016.01.024

Social Science & Medicine

Volume 153, March 2016, Pages 99-106

https://doi.org/10.1016/j.socscimed.2016.01.024 Get rights and content

Highlights

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De novo collection of a large-scale sociocentric health-based social network in India.
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Vaccine refusers nominate twice the number of refusers compared to non-refusers.
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Vaccine refusers cluster both in the social network and in the neighborhoods.

Abstract

Objectives

Eradication and control of childhood diseases through immunization can only work if parents allow their children to be vaccinated. To learn about social network factors associated with polio vaccine hesitancy, we investigated social and spatial clustering of households by their vaccine acceptance status in Malegaon, India, an area known for vaccine refusal and repeated detection of polio cases.

Methods

We interviewed family heads from 2462 households in 25 neighborhoods in July 2012 and constructed social networks based on advice seeking from other households. We restricted our main analyses to surveyed households for which we also had data on whether they accepted the polio vaccine for their eligible children or not.

Results

Data from 2452 households was retained and these households made 2012 nominations to 830 households. Vaccine-refusing households had fewer outgoing ties than vaccine-accepting households. After excluding 24 isolated households, vaccine-refusing households had 189% more nominations to other vaccine-refusing households (93% more in the largest component of the network) compared to vaccine-accepting households, revealing that vaccine-refusing households cluster in the social network. Since roughly half of all ties connect households within neighborhoods, vaccine-refusing clusters lie in spatially localized “pockets”.

Conclusions

The social (and spatial) clustering of vaccine-refusing households could be leveraged to tailor communication strategies to improve vaccine acceptance and community perceptions of immunization programs for polio and other vaccine-preventable diseases.

Introduction

The Global Polio Eradication Initiative (GPEI), a partnership between national governments and five core agencies, including the World Health Organization (WHO), Rotary International, the US Centers for Disease Control and Prevention (CDC), the United Nations Children's Fund (UNICEF), and the Bill and Melinda Gates Foundation (BMGF) is striving to eradicate polio worldwide. Polio incidence in the developing world, especially among under-served and hard-to-reach populations, has been reduced through increased rates of vaccination supported by sustained media campaigns and by mobilizing community leaders (Obregón et al., 2009). Since its launch, the number of polio cases has been reduced from an estimated 350,000 in 1988 to 358 in 2014 (Data in WHO HQ as of 27 January 2015). In addition, the number of countries with endemic polio has been reduced from 125 to three, namely Pakistan, Afghanistan and Nigeria. India had its last case in 2011 and the whole South-East Asia region was certified polio-free in 2014.

In spite of these achievements, polio remains an international concern. In May 2014, renewed outbreaks led the WHO's International Health Regulations Emergency Committee to declare the situation a Public Health Emergency of International Concern (WHO). In particular, segments of susceptible populations continue to resist having their children vaccinated for a variety of reasons. Rumors and misinformation are likely to propagate through social connections, and they might amplify the rates of vaccine refusal. GPEI supported the present study in order to understand better vaccine-refusing behavior.

That vaccine acceptance might be related to social connections should not be surprising. People are connected, and so their health is connected (Smith and Christakis, 2008). Social networks play an important role in human health and disease, through mechanisms such as provision of social support, social engagement, and access to resources, as well as through the dissemination of information and behaviors (Valente, 2010, Berkman et al., 2000). We would expect the structure of social networks to play a critical role in funneling both information and misinformation, including that related to vaccines (Christakis and Fowler, 2010).

Our goal was to investigate whether the resistance of households to having their young children vaccinated against polio might be related to similar resistance in households to which they are socially connected. If children of unvaccinated households interact frequently, they might reinforce inaccurate beliefs and be substantially more likely to contract and propagate the disease, as herd immunity is reduced within these clusters. Learning about the possible existence of such clusters is therefore critical for eradicating infectious diseases like polio in developing countries by identifying “social pockets” of vaccine hesitancy. Moreover, to the extent that such clusters can be identified, public health officials might be able to use more targeted approaches to overcoming vaccine resistance. We also investigated differences in vaccine acceptance across the surveyed neighborhoods and the geographic distribution of nominations across neighborhoods. This enabled us to distinguish between network and neighborhood effects; in short, does your behavior with respect to polio vaccines depend on whom you know, where you live, or both?

Section snippets

Study design

We carried out a population-based study of 2462 households in contiguous high-risk (by polio planning definitions) neighborhoods in Malegaon Municipal Corporation in the Nashik district of Maharashtra state in the western region of India, about 280 km northeast of Mumbai. The study protocol was reviewed and approved by Research Ethics Review Committee of WHO Geneva and the Haffekine Research Institute Mumbai.

Twenty-five teams each consisting of a professional surveyor (recruited through Nielsen

Results

A total of 2462 household respondents were surveyed, and after excluding 10 respondents due to incomplete data, 2452 (or 99.6%) of the households approached for the interview were included in the study. Of these, 1355 included a child between the ages of 0 and 5 eligible for the vaccine for whom we had data on vaccine status; the ineligible households reported not having children in this age category and were excluded. Among eligible households, 1074 accepted the vaccine, 137 were reluctant,

Discussion

Using a population-based, household-level survey in Malegaon, India, we find that vaccine-refusing households have fewer outgoing ties than vaccine-accepting households and that they had fewer health ties than vaccine-accepting households. Moreover, the surveyed neighborhoods varied significantly by their vaccine status composition, and, on average, 49% of network nominations were to households in the same neighborhood. This suggests that social ties are spatially localized. Finally,

Acknowledgments

Sae Takada (Harvard Medical School) assisted with study design in India; Jeanette Lorme (Department of Biostatistics, Harvard T.H. Chan School of Public Health) helped with manuscript preparation. The following individuals and entities assisted with study coordination, logistics, surveying, data collection, and data coding: Alexandra Brown (WHO Geneva), Ravindra Banpel, Chetan Khade, Hemant Kharnare, Mujib Janu Sayyed (WHO-India), Preeti Dass (UNICEF India), The Nielsen (India) Private Limited,

References (24)

L.F. Berkman et al.
From social integration to health: Durkheim in the new millennium
Soc. Sci. Med.
(2000)
S. Borgatti et al.
Analyzing Social Networks
(2013)
N.A. Christakis et al.
The spread of obesity in a large social network over 32 years
N. Engl. J. Med.
(2007)
N.A. Christakis et al.
The collective dynamics of smoking in a large social network
N. Engl. J. Med.
(2008)
N.A. Christakis et al.
Social network sensors for early detection of contagious outbreaks
PLoS ONE
(2010)
N.A. Christakis et al.
Social contagion theory: examining dynamic social networks and human behavior
Stat. Med.
(2013)
P.D. Hoff et al.
Latent space approaches to social network analysis
J. Am. Stat. Assoc.
(2002)
H.J. Larson et al.
Lessons from polio eradication
Nature
(2011)
D. Lusher et al.
M. McPherson et al.
Birds of a feather: homophily in social networks
Annu. Rev. Sociol.
(2001)

M.E.J. Newman

Networks: An Introduction

(2010)

B. Nyhan et al.

Effective messages in vaccine promotion: a randomized trial

Pediatrics

(2014)

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For example, Alvergne et al. (2011) collected friendship network data in four villages in southern Ethiopia to investigate the effect of social networks on the spread of modern contraception. Onnela et al. (2016) used paper-based questionnaires to collect information about network contacts to investigate the polio vaccine hesitancy in India. Kamya et al. (2017) conducted structured social network surveys with key individuals involved in the HPV vaccine application process in Uganda.
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Onnela et al. thus demonstrated that in Malegaon, India, households opposed to vaccination were socially and geographically connected. They formed clusters or pockets of resistance to vaccination [25]. Better knowledge of the socio-spatial distribution of vaccine hesitancy could lead to more targeted interventions to promote vaccination.
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View full text

Polio vaccine hesitancy in the networks and neighborhoods of Malegaon, India

Highlights

Abstract

Objectives

Methods

Results

Conclusions

Introduction

Section snippets

Study design

Results

Discussion

Acknowledgments

Soc. Sci. Med.

Analyzing Social Networks

The spread of obesity in a large social network over 32 years

N. Engl. J. Med.

The collective dynamics of smoking in a large social network

N. Engl. J. Med.

Social network sensors for early detection of contagious outbreaks

PLoS ONE

Social contagion theory: examining dynamic social networks and human behavior

Stat. Med.

Latent space approaches to social network analysis

J. Am. Stat. Assoc.

Lessons from polio eradication

Nature

Birds of a feather: homophily in social networks

Annu. Rev. Sociol.

Networks: An Introduction

Effective messages in vaccine promotion: a randomized trial

Pediatrics