Abstract and Introduction
Abstract
Objectives: To assess the association between individual-level adherence to social-distancing and personal hygiene behaviors recommended by public health experts and subsequent risk of COVID-19 diagnosis in the United States.
Methods: Data are from waves 7 through 26 (June 10, 2020–April 26, 2021) of the Understanding America Study COVID-19 survey. We used Cox models to assess the relationship between engaging in behaviors considered high risk and risk of COVID-19 diagnosis.
Results: Individuals engaging in behaviors indicating lack of adherence to social-distancing guidelines, especially those related to large gatherings or public interactions, had a significantly higher risk of COVID-19 diagnosis than did those who did not engage in these behaviors. Each additional risk behavior was associated with a 9% higher risk of COVID-19 diagnosis (hazard ratio [HR] = 1.09; 95% confidence interval [CI] = 1.05, 1.13). Results were similar after adjustment for sociodemographic characteristics and local infection rates.
Conclusions: Personal mitigation behaviors appear to influence the risk of COVID-19, even in the presence of social factors related to infection risk.
Public Health Implications: Our findings emphasize the importance of individual behaviors for preventing COVID-19, which may be relevant in contexts with low vaccination.
Introduction
COVID-19 continues to be a major public health concern in the United States and worldwide. Since its recognition in late 2019 through August 2021, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 215 million individuals globally, with more than 39 million cases in the United States alone.[1] These cases have resulted in an enormous mortality toll: COVID-19 was the third-leading cause of death in the United States in 2020, and it reduced 2020 US life expectancy by more than a year.[2,3] At the time of writing (August 2021), many areas of the United States are experiencing surges of cases fueled by the highly transmissible Delta variant, and the Centers for Disease Control and Prevention (CDC) has revised its guidance to again recommend indoor masking for all individuals in high-transmission areas, regardless of vaccination status.[4]
Stopping the pandemic still requires using all available tools, including simple behavioral modifications. Government officials and public health experts have been urging people to engage in preventive behaviors, including wearing a mask that covers the nose and mouth, staying 6 feet apart from others, avoiding crowds and poorly ventilated indoor spaces, and washing hands often with soap and water or hand sanitizer.[5]
Empirical evidence has shown that social-distancing and personal hygiene recommendations or mandates at aggregate levels effectively slow the spread of the virus. In the United States, county-level and state-level mask mandates have significantly reduced the growth rates of local COVID-19 cases.[6–10] By the end of 2020, mask mandate policies were found to be associated with significant reductions in the growth rates of county-level daily case numbers and deaths within a month of implementation, as well as reductions in state-level cases.[6,7,9,11] Studies have also found that other nonpharmaceutical policy interventions, such as quarantine of exposed individuals, social distancing, workplace closures, and restrictions on large gatherings and events, help reduce the spread of the virus.[6,8,11–15] For example, reopening restaurant dining increased the growth rates of county-level cases and deaths within 41 to 80 days of reopening.[6] Isolation or quarantine, social distancing, and traffic restriction policies were found to have reduced the reproduction number of the disease by up to 43%.[11] Notably, the stringency of control measures was associated with greater reductions in disease proliferation.[15]
The effectiveness of preventive behaviors undertaken by individuals remains unclear, likely because of limitations of existing data sources. Studies on the topic have primarily been retrospective studies or case–control studies,[16–20] which may be biased by inaccurate recall of past behavior. A recent study linked preventive behaviors to COVID-19 infection using prospective data, but it focused on a limited set of social-distancing behaviors, captured infections through only October 2020, and was based on a sample that may not be widely generalizable.[21] Population-level studies have typically focused on large gatherings or public spaces as sources of exposure to COVID-19, but there has been less evidence about the risk of COVID-19 from smaller gatherings, which were less amenable to policy interventions.[22] Although individuals who repeatedly engage in risky behaviors likely have a higher risk of COVID-19 infection than those who do not, no nationally representative research has examined the cumulative role of individual behaviors in determining the risk of COVID-19 infection.
We addressed these gaps in the literature by using the Understanding America Study (UAS) survey, one of the only nationally representative longitudinal data sources that assess changes in behaviors that affect one’s risk of COVID-19 infection over time. We hypothesized that not practicing the recommended social distancing or COVID-19–related personal hygiene behaviors would elevate the risk of COVID-19 infection and that the risk of COVID-19 infection would increase with engagement in additional numbers of risky behaviors.