Individually optimal choices can be collectively disastrous in COVID-19 disease control

Abstract

Background The word ‘pandemic’ conjures dystopian images of bodies stacked in the streets and societies on the brink of collapse. Despite this frightening picture, denialism and noncompliance with public health measures are common in the historical record, for example during the 1918 Influenza pandemic or the 2015 Ebola epidemic. The unique characteristics of SARS-CoV-2—its high basic reproduction number (R0), time-limited natural immunity and considerable potential for asymptomatic spread—exacerbate the public health repercussions of noncompliance with interventions (such as vaccines and masks) to limit disease transmission. Our work explores the rationality and impact of noncompliance with measures aimed at limiting the spread of SARS-CoV-2. Methods In this work, we used game theory to explore when noncompliance confers a perceived benefit to individuals. We then used epidemiological modeling to predict the impact of noncompliance on control of SARS-CoV-2, demonstrating that the presence of a noncompliant subpopulation prevents suppression of disease spread. Results Our modeling demonstrates that noncompliance is a Nash equilibrium under a broad set of conditions and that the existence of a noncompliant population can result in extensive endemic disease in the long-term after a return to pre-pandemic social and economic activity. Endemic disease poses a threat for both compliant and noncompliant individuals; all community members are protected if complete suppression is achieved, which is only possible with a high degree of compliance. For interventions that are highly effective at preventing disease spread, however, the consequences of noncompliance are borne disproportionately by noncompliant individuals. Conclusions In sum, our work demonstrates the limits of free-market approaches to compliance with disease control measures during a pandemic. The act of noncompliance with disease intervention measures creates a negative externality, rendering suppression of SARS-CoV-2 spread ineffective. Our work underscores the importance of developing effective strategies for prophylaxis through public health measures aimed at complete suppression and the need to focus on compliance at a population level.

Determinants of COVID-19 skepticism and SARS-CoV-2 vaccine hesitancy: findings from a national population survey of U.S. adults

“…Up to now, exposing the myths inherent in skepticism and hesitancy has been ineffective in countering resistance to immunization. Noncompliance with primary-preventive measures remains “a significant impediment to suppression of SARS-CoV-2 spread” and thus requires more creative approaches [ 43 ]. For example, providing evidence of the dangers of communicable disease exposure to unvaccinated individuals, especially vulnerable loved ones such as children, was found to be a better strategy to combat antivaccination attitudes pre-COVID-19 [ 44 ].…”

COVID-19 Vaccine Hesitancy in Three Latin American Countries: Reasons Given for Not Becoming Vaccinated in Colombia, Ecuador, and Venezuela

“…Although prevention measures such as mask wearing, social distancing, and handwashing have been used to slow the spread of COVID-19 (Regmi & Lwin, 2021), the development of several vaccines is essential to prevent this disease and stop the pandemic (Robinson et al, 2021). The rapid development of these vaccines is an important achievement, but it is essential that people who can be vaccinated become vaccinated because noncompliance threatens public health (Stoddard et al, 2021). Indeed, it has been estimated that a minimum of 75-80% of a country's population be vaccinated to prevent future outbreaks (Adil Mahmoud Yousif et al, 2021).…”

The impact of vaccination frequency on COVID-19 public health outcomes: A model-based analysis

“…Modeling studies have had substantial predictive value during the course of this pandemic. Our team has used model-based approaches to predict the rapid pace of evolutionary immune evasion [68], the inability of vaccines to enable a return to pre-pandemic conditions [69], the tendency of noncompliance with mitigation measures to incentivize further noncompliance [70], and the rapid variantdriven rebound observed upon premature relaxation of mitigation measures [71]. In each of these cases, our predictions were made months in advance [72][73][74][75].…”