1
|
Oraby T, Balogh A. Modeling the effect of observational social learning on parental decision-making for childhood vaccination and diseases spread over household networks. FRONTIERS IN EPIDEMIOLOGY 2024; 3:1177752. [PMID: 38455928 PMCID: PMC10910890 DOI: 10.3389/fepid.2023.1177752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 12/27/2023] [Indexed: 03/09/2024]
Abstract
In this paper, we introduce a novel model for parental decision-making about vaccinations against a childhood disease that spreads through a contact network. This model considers a bilayer network comprising two overlapping networks, which are either Erdős-Rényi (random) networks or Barabási-Albert networks. The model also employs a Bayesian aggregation rule for observational social learning on a social network. This new model encompasses other decision models, such as voting and DeGroot models, as special cases. Using our model, we demonstrate how certain levels of social learning about vaccination preferences can converge opinions, influencing vaccine uptake and ultimately disease spread. In addition, we explore how two different cultures of social learning affect the establishment of social norms of vaccination and the uptake of vaccines. In every scenario, the interplay between the dynamics of observational social learning and disease spread is influenced by the network's topology, along with vaccine safety and availability.
Collapse
Affiliation(s)
- Tamer Oraby
- School of Mathematical and Statistical Sciences, The University of Texas Rio Grande Valley, Edinburg, TX, United States
| | | |
Collapse
|
2
|
d'Albis H, Etner J, Thuilliez J. Vaccination under pessimistic expectations in clinical trials and immunization campaigns. JOURNAL OF PUBLIC ECONOMIC THEORY 2022; 25:JPET12617. [PMID: 36246735 PMCID: PMC9538933 DOI: 10.1111/jpet.12617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 08/16/2022] [Accepted: 08/21/2022] [Indexed: 06/16/2023]
Abstract
We provide one of the first formalizations of a vaccination campaign in a decision-theoretic framework. We analyze a model where an ambiguity-averse individual must decide how much effort to invest into prevention in the context of a rampant disease. We study how ambiguity aversion affects the effort and the estimation of the vaccine efficacy in clinical trials and immunization campaigns. We find that the behaviors of individuals participating in a clinical trial differ from individuals not participating. Individuals who are more optimistic toward vaccination participate more in trials. Their behaviors and efforts are also affected. As a result, because vaccine efficacy depends on unobserved behaviors and efforts, the biological effect of the vaccine becomes difficult to evaluate. During the scale-up phase of a vaccination campaign, provided that vaccine efficacy is established, we show that vaccine hesitancy may still be rational.
Collapse
Affiliation(s)
| | - Johanna Etner
- EconomiX, UPL, Paris Nanterre UniversityCNRSParisFrance
| | - Josselin Thuilliez
- CNRS—Centre d'Economie de la Sorbonne, UMR8174Université Panthéon‐Sorbonne‐CNRSParisFrance
| |
Collapse
|
3
|
Azarpanah H, Farhadloo M, Vahidov R, Pilote L. Vaccine hesitancy: evidence from an adverse events following immunization database, and the role of cognitive biases. BMC Public Health 2021; 21:1686. [PMID: 34530804 PMCID: PMC8444164 DOI: 10.1186/s12889-021-11745-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/29/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Vaccine hesitancy has been a growing challenge for public health in recent decades. Among factors contributing to vaccine hesitancy, concerns regarding vaccine safety and Adverse Events (AEs) play the leading role. Moreover, cognitive biases are critical in connecting such concerns to vaccine hesitancy behaviors, but their role has not been comprehensively studied. In this study, our first objective is to address concerns regarding vaccine AEs to increase vaccine acceptance. Our second objective is to identify the potential cognitive biases connecting vaccine hesitancy concerns to vaccine-hesitant behaviors and identify the mechanism they get triggered in the vaccine decision-making process. METHODS First, to mitigate concerns regarding AEs, we quantitatively analyzed the U.S. Vaccine Adverse Event Reporting System (VAERS) from 2011 to 2018 and provided evidence regarding the non-severity of the AEs that can be used as a communicable summary to increase vaccine acceptance. Second, we focused on the vaccination decision-making process. We reviewed cognitive biases and vaccine hesitancy literature to identify the most potential cognitive biases that affect vaccine hesitancy and categorized them adopting the Precaution Adoption Process Model (PAPM). RESULTS Our results show that the top frequent AEs are expected mild reactions like injection site erythema (4.29%), pyrexia (3.66%), and injection site swelling (3.21%). 94.5% of the reports are not serious and the average population-based serious reporting rate over the 8 years was 25.3 reports per 1 million population. We also identified 15 potential cognitive biases that might affect people's vaccination decision-making and nudge them toward vaccine hesitancy. We categorized these biases based on the factors that trigger them and discussed how they contribute to vaccine hesitancy. CONCLUSIONS This paper provided an evidence-based communicable summary of VAERS. As the most trusted sources of vaccine information, health practitioners can use this summary to provide evidence-based vaccine information to vaccine decision-makers (patients/parents) and mitigate concerns over vaccine safety and AEs. In addition, we identified 15 potential cognitive biases that might affect the vaccination decision-making process and nudge people toward vaccine hesitancy. Any plan, intervention, and message to increase vaccination uptake should be modified to decrease the effect of these potential cognitive biases.
Collapse
Affiliation(s)
- Hossein Azarpanah
- John Molson School of Business, Concordia University, 1450 Guy St, Montreal, Quebec, H3H 0A1, Canada.
| | - Mohsen Farhadloo
- John Molson School of Business, Concordia University, 1450 Guy St, Montreal, Quebec, H3H 0A1, Canada
| | - Rustam Vahidov
- John Molson School of Business, Concordia University, 1450 Guy St, Montreal, Quebec, H3H 0A1, Canada
| | - Louise Pilote
- Centre for Outcomes Research and Evaluation, McGill University, 5252 De Maisonneuve Blvd, Montreal, Quebec, H4A 3S5, Canada
| |
Collapse
|
4
|
Ferreira PL, Santos FC, Pequito S. Risk sensitivity and theory of mind in human coordination. PLoS Comput Biol 2021; 17:e1009167. [PMID: 34264938 PMCID: PMC8315544 DOI: 10.1371/journal.pcbi.1009167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 07/27/2021] [Accepted: 06/09/2021] [Indexed: 11/19/2022] Open
Abstract
What humans do when exposed to uncertainty, incomplete information, and a dynamic environment influenced by other agents remains an open scientific challenge with important implications in both science and engineering applications. In these contexts, humans handle social situations by employing elaborate cognitive mechanisms such as theory of mind and risk sensitivity. Here we resort to a novel theoretical model, showing that both mechanisms leverage coordinated behaviors among self-regarding individuals. Particularly, we resort to cumulative prospect theory and level-k recursions to show how biases towards optimism and the capacity of planning ahead significantly increase coordinated, cooperative action. These results suggest that the reason why humans are good at coordination may stem from the fact that we are cognitively biased to do so. We propose a new computational model characterizing coordination among self-regarding individuals under theory of mind and risk sensitivity. Theory of mind enables decision-making based on the attribution of beliefs, knowledge, or goals to others, whereas different risk sensitivities allows one to assess the impact of different ways of valuing uncertain returns, as captured by descriptive theories from social-economic studies. Together they provide evidence that biases towards optimism, and the capacity for planning ahead, significantly increase coordinated, cooperative action.
Collapse
Affiliation(s)
- Pedro L. Ferreira
- INESC-ID and Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Francisco C. Santos
- INESC-ID and Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Sérgio Pequito
- Center for Systems and Control, Delft University of Technology, Delft, Netherlands
- * E-mail:
| |
Collapse
|
5
|
Tomljenovic H, Bubic A, Erceg N. Contribution of rationality to vaccine attitudes: Testing two hypotheses. JOURNAL OF BEHAVIORAL DECISION MAKING 2021; 35:e2260. [PMID: 34518738 PMCID: PMC8426977 DOI: 10.1002/bdm.2260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/17/2021] [Accepted: 06/17/2021] [Indexed: 12/03/2022]
Abstract
Although previous studies have demonstrated an association between vaccine attitudes and cognitive biases, often resulting in vaccination hesitancy, the exact contribution of rationality has not been fully clarified. We tested two hypotheses regarding the impact of rationality on vaccine attitudes stemming from bounded and expressive rationality. We focused on parental vaccine attitudes operationalized by the affective, behavioral, and cognitive attitude components and investigated how these are influenced by disillusionment toward authorities and ability to engage in rational thinking operationalized using cognitive reflection and heuristics and biases tasks. The study was of a cross‐sectional correlational design with a non‐probabilistic sample of 823 volunteer participants surveyed online in April and May 2018 in Croatia. The results identified disillusionment toward authorities as a predictor of all components. Furthermore, performance on heuristics and biases tasks also predicted the affective and cognitive, but not the behavioral component, whereas cognitive reflection had no impact on vaccine attitudes. Next, a moderation effect of disillusionment toward authorities on the association between the omission bias task and all attitude components was identified. Parents with low disillusionment demonstrated positive vaccine attitudes regardless of their rationality, whereas for parents with high disillusionment a significant positive correlation between performance on the omission bias task as assessed with a vaccination vignette and attitudes was identified. This suggests that the ability to resist vaccine specific omission bias, that is, higher rationality, can decrease the negative effects of disillusionment, which supports the bounded rationality hypothesis.
Collapse
Affiliation(s)
| | - Andreja Bubic
- Faculty of Humanities and Social Sciences University of Split Split Croatia
| | - Nikola Erceg
- Faculty of Humanities and Social Sciences University of Zagreb Zagreb Croatia
| |
Collapse
|
6
|
Wagner CE, Prentice JA, Saad-Roy CM, Yang L, Grenfell BT, Levin SA, Laxminarayan R. Economic and Behavioral Influencers of Vaccination and Antimicrobial Use. Front Public Health 2020; 8:614113. [PMID: 33409264 PMCID: PMC7779682 DOI: 10.3389/fpubh.2020.614113] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/01/2020] [Indexed: 01/07/2023] Open
Abstract
Despite vast improvements in global vaccination coverage during the last decade, there is a growing trend in vaccine hesitancy and/or refusal globally. This has implications for the acceptance and coverage of a potential vaccine against COVID-19. In the United States, the number of children exempt from vaccination for “philosophical belief-based” non-medical reasons increased in 12 of the 18 states that allowed this policy from 2009 to 2017 (1). Meanwhile, the overuse and misuse of antibiotics, especially in young children, have led to increasing rates of drug resistance that threaten our ability to treat infectious diseases. Vaccine hesitancy and antibiotic overuse exist side-by-side in the same population of young children, and it is unclear why one modality (antibiotics) is universally seen as safe and effective, while the other (vaccines) is seen as potentially hazardous by some. In this review, we consider the drivers shaping the use of vaccines and antibiotics in the context of three factors: individual incentives, risk perceptions, and social norms and group dynamics. We illustrate how these factors contribute to the societal and individual costs of vaccine underuse and antimicrobial overuse. Ultimately, we seek to understand these factors that are at the nexus of infectious disease epidemiology and social science to inform policy-making.
Collapse
Affiliation(s)
- Caroline E Wagner
- Department of Bioengineering, McGill University, Montreal, QC, Canada
| | - Joseph A Prentice
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States
| | - Chadi M Saad-Roy
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, United States
| | - Luojun Yang
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States
| | - Bryan T Grenfell
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States.,Princeton School of Public and International Affairs, Princeton University, Princeton, NJ, United States.,Fogarty International Center, National Institutes of Health, Bethesda, MD, United States
| | - Simon A Levin
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States.,Princeton Environmental Institute, Princeton University, Princeton, NJ, United States
| | - Ramanan Laxminarayan
- Princeton Environmental Institute, Princeton University, Princeton, NJ, United States.,Center for Disease Dynamics, Economics & Policy, Washington, DC, United States
| |
Collapse
|
7
|
Li XJ, Li X. Vaccinating SIS epidemics under evolving perception in heterogeneous networks. THE EUROPEAN PHYSICAL JOURNAL. B 2020; 93:185. [PMID: 33024413 PMCID: PMC7531267 DOI: 10.1140/epjb/e2020-10355-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/10/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
ABSTRACT Vaccination is an effective intervention against epidemics. Previous work has demonstrated that psychological cognition affects individual behavior. However, perceptual differences between individuals, as well as the dynamics of perceptual evolution, are not taken into account. In order to explore how these realistic characteristics of psychological cognition influence collective vaccination behavior, we propose a prospect theory based evolutionary vaccination game model, where the evolution of reference points is used to characterize changes in perception. We compare the fractions of vaccinated individuals and infected individuals under variable reference points with those under the expected utility theory and the fixed reference point, and highlight the role of evolving perception in promoting vaccination and contributing to epidemic control. We find that the epidemic size under variable reference point is always less than that under the expected utility theory. Finding that there exists a vaccination cost threshold for the cognitive effect, we develop a novel mixed-reference-point mechanism by combining individual psychological characteristics with network topological feature. The effectiveness of this mechanism in controlling the network epidemics is verified with numerical simulations. Compared with pure reference points, the mixed-reference-point mechanism can effectively reduce the final epidemic size, especially at a large vaccination cost.
Collapse
Affiliation(s)
- Xiao-Jie Li
- Adaptive Networks and Control Lab, Department of Electronic Engineering – Fudan University, Shanghai, 200433 P.R. China
| | - Xiang Li
- Adaptive Networks and Control Lab, Department of Electronic Engineering – Fudan University, Shanghai, 200433 P.R. China
- Research Center of Smart Networks and Systems, School of Information Science and Engineering – Fudan University, Shanghai, 200433 P.R. China
- MOE Frontiers Center for Brain Science, Institutes of Brain Science – Fudan University, Shanghai, 200433 P.R. China
| |
Collapse
|
8
|
Wells CR, Huppert A, Fitzpatrick MC, Pandey A, Velan B, Singer BH, Bauch CT, Galvani AP. Prosocial polio vaccination in Israel. Proc Natl Acad Sci U S A 2020; 117:13138-13144. [PMID: 32457142 PMCID: PMC7293608 DOI: 10.1073/pnas.1922746117] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Regions with insufficient vaccination have hindered worldwide poliomyelitis eradication, as they are vulnerable to sporadic outbreaks through reintroduction of the disease. Despite Israel's having been declared polio-free in 1988, a routine sewage surveillance program detected polio in 2013. To curtail transmission, the Israel Ministry of Health launched a vaccine campaign to vaccinate children-who had only received the inactivated polio vaccine-with the oral polio vaccine (OPV). Determining the degree of prosocial motivation in vaccination behavior is challenging because vaccination typically provides direct benefits to the individual as well as indirect benefits to the community by curtailing transmission. However, the Israel OPV campaign provides a unique and excellent opportunity to quantify and model prosocial vaccination as its primary objective was to avert transmission. Using primary survey data and a game-theoretical model, we examine and quantify prosocial behavior during the OPV campaign. We found that the observed vaccination behavior in the Israeli OPV campaign is attributable to prosocial behavior and heterogeneous perceived risk of paralysis based on the individual's comprehension of the prosocial nature of the campaign. We also found that the benefit of increasing comprehension of the prosocial nature of the campaign would be limited if even 24% of the population acts primarily from self-interest, as greater vaccination coverage provides no personal utility to them. Our results suggest that to improve coverage, communication efforts should also focus on alleviating perceived fears surrounding the vaccine.
Collapse
Affiliation(s)
- Chad R Wells
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT 06520
| | - Amit Huppert
- The Biostatistics & Biomathematics Unit, The Gertner Institute for Epidemiology and Health Policy Research, Sheba Medical Center, Tel Hashomer, 52621 Ramat Gan, Israel
- School of Public Health, The Sackler Faculty of Medicine, Tel-Aviv University, 69978 Tel Aviv, Israel
| | - Meagan C Fitzpatrick
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT 06520
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Abhishek Pandey
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT 06520
| | - Baruch Velan
- The Biostatistics & Biomathematics Unit, The Gertner Institute for Epidemiology and Health Policy Research, Sheba Medical Center, Tel Hashomer, 52621 Ramat Gan, Israel
| | - Burton H Singer
- Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610;
| | - Chris T Bauch
- Department of Applied Mathematics, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Alison P Galvani
- Center for Infectious Disease Modeling and Analysis, Yale School of Public Health, New Haven, CT 06520
| |
Collapse
|
9
|
Infection prevention behaviour and infectious disease modelling: a review of the literature and recommendations for the future. BMC Public Health 2018. [PMID: 29523125 PMCID: PMC5845221 DOI: 10.1186/s12889-018-5223-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background Given the importance of person to person transmission in the spread of infectious diseases, it is critically important to ensure that human behaviour with respect to infection prevention is appropriately represented within infectious disease models. This paper presents a large scale scoping review regarding the incorporation of infection prevention behaviour in infectious disease models. The outcomes of this review are contextualised within the psychological literature concerning health behaviour and behaviour change, resulting in a series of key recommendations for the incorporation of human behaviour in future infectious disease models. Methods The search strategy focused on terms relating to behaviour, infectious disease and mathematical modelling. The selection criteria were developed iteratively to focus on original research articles that present an infectious disease model with human-human spread, in which individuals’ self-protective health behaviour varied endogenously within the model. Data extracted included: the behaviour that is modelled; how this behaviour is modelled; any theoretical background for the modelling of behaviour, and; any behavioural data used to parameterise the models. Results Forty-two papers from an initial total of 2987 were retained for inclusion in the final review. All of these papers were published between 2002 and 2015. Many of the included papers employed a multiple, linked models to incorporate infection prevention behaviour. Both cognitive constructs (e.g., perceived risk) and, to a lesser extent, social constructs (e.g., social norms) were identified in the included papers. However, only five papers made explicit reference to psychological health behaviour change theories. Finally, just under half of the included papers incorporated behavioural data in their modelling. Conclusions By contextualising the review outcomes within the psychological literature on health behaviour and behaviour change, three key recommendations for future behavioural modelling are made. First, modellers should consult with the psychological literature on health behaviour/ behaviour change when developing new models. Second, modellers interested in exploring the relationship between behaviour and disease spread should draw on social psychological literature to increase the complexity of the social world represented within infectious disease models. Finally, greater use of context-specific behavioural data (e.g., survey data, observational data) is recommended to parameterise models. Electronic supplementary material The online version of this article (10.1186/s12889-018-5223-1) contains supplementary material, which is available to authorized users.
Collapse
|
10
|
Verelst F, Willem L, Beutels P. Behavioural change models for infectious disease transmission: a systematic review (2010-2015). J R Soc Interface 2016; 13:20160820. [PMID: 28003528 PMCID: PMC5221530 DOI: 10.1098/rsif.2016.0820] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/25/2016] [Indexed: 12/13/2022] Open
Abstract
We review behavioural change models (BCMs) for infectious disease transmission in humans. Following the Cochrane collaboration guidelines and the PRISMA statement, our systematic search and selection yielded 178 papers covering the period 2010-2015. We observe an increasing trend in published BCMs, frequently coupled to (re)emergence events, and propose a categorization by distinguishing how information translates into preventive actions. Behaviour is usually captured by introducing information as a dynamic parameter (76/178) or by introducing an economic objective function, either with (26/178) or without (37/178) imitation. Approaches using information thresholds (29/178) and exogenous behaviour formation (16/178) are also popular. We further classify according to disease, prevention measure, transmission model (with 81/178 population, 6/178 metapopulation and 91/178 individual-level models) and the way prevention impacts transmission. We highlight the minority (15%) of studies that use any real-life data for parametrization or validation and note that BCMs increasingly use social media data and generally incorporate multiple sources of information (16/178), multiple types of information (17/178) or both (9/178). We conclude that individual-level models are increasingly used and useful to model behaviour changes. Despite recent advancements, we remain concerned that most models are purely theoretical and lack representative data and a validation process.
Collapse
Affiliation(s)
- Frederik Verelst
- Centre for Health Economics Research and Modelling Infectious Diseases, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Lander Willem
- Centre for Health Economics Research and Modelling Infectious Diseases, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Philippe Beutels
- Centre for Health Economics Research and Modelling Infectious Diseases, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- School of Public Health and Community Medicine, The University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
11
|
Beyond Rational Decision-Making: Modelling the Influence of Cognitive Biases on the Dynamics of Vaccination Coverage. PLoS One 2015; 10:e0142990. [PMID: 26599688 PMCID: PMC4657916 DOI: 10.1371/journal.pone.0142990] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/29/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Theoretical studies predict that it is not possible to eradicate a disease under voluntary vaccination because of the emergence of non-vaccinating "free-riders" when vaccination coverage increases. A central tenet of this approach is that human behaviour follows an economic model of rational choice. Yet, empirical studies reveal that vaccination decisions do not necessarily maximize individual self-interest. Here we investigate the dynamics of vaccination coverage using an approach that dispenses with payoff maximization and assumes that risk perception results from the interaction between epidemiology and cognitive biases. METHODS We consider a behaviour-incidence model in which individuals perceive actual epidemiological risks as a function of their opinion of vaccination. As a result of confirmation bias, sceptical individuals (negative opinion) overestimate infection cost while pro-vaccines individuals (positive opinion) overestimate vaccination cost. We considered a feedback between individuals and their environment as individuals could change their opinion, and thus the way they perceive risks, as a function of both the epidemiology and the most common opinion in the population. RESULTS For all parameter values investigated, the infection is never eradicated under voluntary vaccination. For moderately contagious diseases, oscillations in vaccination coverage emerge because individuals process epidemiological information differently depending on their opinion. Conformism does not generate oscillations but slows down the cultural response to epidemiological change. CONCLUSION Failure to eradicate vaccine preventable disease emerges from the model because of cognitive biases that maintain heterogeneity in how people perceive risks. Thus, assumptions of economic rationality and payoff maximization are not mandatory for predicting commonly observed dynamics of vaccination coverage. This model shows that alternative notions of rationality, such as that of ecological rationality whereby individuals use simple cognitive heuristics, offer promising new avenues for modelling vaccination behaviour.
Collapse
|