Healthy Davis Together: Creating a Model for Community Control of COVID-19

Abstract

While many higher-education institutions dramatically altered their operations and helped mitigate COVID-19 transmission on campuses, these efforts were rarely fully extended to surrounding communities. A community pandemic-response program was launched in a college town that deployed epidemiological infection-control measures and health behavior change interventions. An increase in self-reported preventive health behaviors and a lower relative case positivity proportion were observed. The program identified scalable approaches that may generalize to other college towns and community types. Building public health infrastructure with such programs may be pivotal in promoting health in the postpandemic era. (Am J Public Health. 2022;112(8):1142–1146. https://doi.org/10.2105/AJPH.2022.306880)

In response to the COVID-19 pandemic, many institutions of higher education dramatically altered their operations¹ to mitigate transmission on campuses.² Actions included testing, contact tracing, isolation and quarantine support for students and employees, wastewater monitoring, and a variety of behavior change interventions (e.g., masking, remote classes). While at many institutions of higher education campus life extends into the community where local economies depend on students, few institutions of higher education fully extended their mitigation efforts into their surroundings.³

INTERVENTION AND IMPLEMENTATION

The University of California, Davis (UC Davis) and the City of Davis, located within Yolo County, California, partnered to develop a community COVID-19 pandemic response program, Healthy Davis Together (HDT),⁴ which combined epidemiological infectious disease control measures and health behavior change interventions to mitigate the impact of the COVID-19 pandemic.

Together with UC Davis, the City of Davis, and key community stakeholders, HDT deployed several strategic approaches that fell under two thematic areas: epidemiology (such as testing, contact tracing, and quarantine and isolation) and health behavior change (focused on communication). Project organization is shown in Figure 1.

FIGURE 1—

Healthy Davis Together Program Organization

Note. PPE = personal protective equipment; SARS-CoV-2 = severe acute respiratory syndrome coronavirus 2. Each overarching theme (epidemiology and health behavior change) includes several approaches. Seven enabling cores provide support across the project. The targeted beneficiaries represent components of the Davis community.

Epidemiology strategies included expanding access to polymerase chain reaction (PCR) testing by adding new testing sites to those that were otherwise available to Yolo County residents and by offering voluntary, free-of-charge COVID-19 testing. Additional strategies included augmenting the county’s contact tracing capacity with rapid triage to isolation and quarantine, implementing citywide sub-sewershed–level wastewater monitoring, personal protective equipment (PPE) distribution, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Health behavior change interventions included targeted COVID-19 health education, mass communications through different media channels, and personal, group, and business incentives.

Built on a framework of community trust that meaningfully engaged citizens, businesses, and local government officials in planning and operations, we strengthened partnerships among the university, city, and county, and established new partnerships with private and community entities that enhanced communications capabilities, enabled implementation of joint local responses, and facilitated community-wide testing.

Epidemiological Approaches

SARS-CoV-2 RNA was detected by using a saliva-based reverse transcription‒ quantitative PCR test from the Clinical Laboratory Improvement Amendments‒approved laboratory at the UC Davis Genome Center for asymptomatic individuals who live or work in Davis. BinaxNOW point-of-care tests⁵ were administered for symptomatic individuals. Testing was offered to all Davis kindergarten through grade 12 schools. Quarantine and isolation facilities were offered to newly identified cases and close contacts, along with other need-based wraparound services such as housing, food, and transportation support. Administrative data were used to target some interventions to marginalized populations including persons with less than a four-year college degree, unemployed individuals, the Latinx community, those who were retired or aged 65 years or older, farmworkers, people living in high-density or congregate housing, and individuals utilizing government assistance. Wastewater from the treatment plant and from autosamplers located at 25 subsewershed nodes throughout the city were analyzed for the presence of SARS-CoV-2 RNA by reverse transcriptase‒droplet digital PCR.

A PPE procurement and distribution system for Davis residents was established at easily accessible locations (e.g., campus, businesses, K–12 schools, homeless shelters). When COVID-19 vaccines became available, we partnered with Yolo County Public Health and CommuniCare, a multicounty Federally Qualified Health Center, to equitably augment vaccination access.

Health Behavior Change Approaches

HDT implemented several health behavior‒change approaches to prevent community spread. A new workforce of more than 200 “Aggie” public health ambassador students was established and deployed on campus and throughout Davis. Ambassadors encouraged healthy behaviors through educational messaging, championing health-promoting behaviors, and distributing incentives. Mass communications, used to drive testing and health-promoting behaviors, were aimed at general as well as specific sectors of the community using print, broadcast, and social media. Incentives included gift cards, PPE, hand sanitizer, snacks and meals, HDT merchandise, prize drawings, and small grants for group-coordinated activities. A business partners program provided onsite consulting to help business owners adopt or adapt practices to increase safety and provided partners with grants, PPE, employee COVID-19 testing, patron incentives, marketing, and public health educational materials.

PLACE, TIME, AND PERSONS

HDT began implementing community-wide interventions on November 18, 2020, in Davis. HDT extended campus efforts (for 39 074 students enrolled in fall 2020)⁴ to the entire community that worked or lived in Davis (with a city population of approximately 70 000 residents).

PURPOSE

Our goal was to determine whether a program combining epidemiological infectious disease‒control measures and health behavior‒change interventions could lower the burden of COVID-19 beyond university campus borders and into an entire surrounding community.

EVALUATION AND ADVERSE EFFECTS

We assessed knowledge and practice of COVID-19 health behaviors through a series of repeated cross-sectional surveys using a randomly selected sample of approximately 600 individuals (equally stratified by City of Davis residents or Yolo County residents outside of Davis). We summarized test positivity using a seven-day moving average. We assessed change in test positivity proportion over time using a repeated-measures expanded beta-distributed generalized linear mixed-effects model to compare Davis with non-Davis.

From November 18, 2020, through February 23, 2022, there were 733 606 tests conducted in the Davis community with 13 066 positive results. In September 2021, individuals who reported testing at least once were 85.0% versus 75.5% for Davis residents versus non‒ Davis residents, respectively (P = .002; Table A, available as a supplement to the online version of this article at https://ajph.org). In November 2021, testing rates further increased to 92.3% versus 79.1% (P < .001), and 72.3% of Davis residents reported being tested three or more times compared with 41.8% for non‒Davis residents (P = .029). For Davis residents, 95.0% reported being fully vaccinated in November 2021 compared with 80.4% of non‒Davis residents (P = .034).

Figure 2 shows the test positivity proportion for Davis, Yolo County,⁶ and California from January 1, 2021, to February 23, 2022. Positivity was lower in Davis compared with Yolo County as a whole (overall difference –1.42; 95% confidence interval [CI] = –1.45, –1.38), and significantly lower for Davis compared with California (overall difference –2.15; 95% CI = –2.18, –2.12). Positivity was significantly lower for Yolo County compared with California (overall difference –0.73; 95% CI = –0.75, –0.71). During both the SARS-CoV-2 Delta and Omicron surges, more striking differences were observed when positivity proportion remained lower in Davis in contrast to the steep increases in Yolo County and California.

FIGURE 2—

Comparison of Test Positivity Proportion for the State of California, Yolo County, and the City of Davis: January 1, 2021, to February 23, 2022

Note. The 95% colored confidence bands were estimated from a beta-generalized linear mixed-effects model regression of seven-day moving average positivity proportions. State of California data exclude all Yolo County residents; however, Yolo County data include Davis residents.

Because the pandemic’s deadly consequences accelerated the timeline for implementing control measures, our ability to evaluate incremental contributions of each program component was limited. While many components targeted Davis residents, there was spillover to individuals who lived outside of Davis; some interventions such as PCR testing were made available to individuals who worked in Davis but resided elsewhere. Therefore, positivity proportion comparisons by geographic area may be biased by spillover effects, although most likely in the direction of the null value. The observed differences in positivity between Davis and Yolo County are likely understated. No adverse effects were reported or observed that were attributed to project interventions.

SUSTAINABILITY

Several HDT elements directly contributed to the development of local infrastructure in response to the COVID-19 pandemic and can be leveraged to address future public health challenges. These include new or strengthened public‒public and public‒private partnerships, an undergraduate community health promotion workforce, relatively low-cost measures such as multilevel incentives, and community-wide testing that can be used for other infectious agents. Even measures that required substantial upfront capital investment, like establishing our PCR testing platform, resulted in reduced unit costs more than an order of magnitude less expensive than commercial alternatives and rapidly returned results (typically within ≤ 24 hours). While the utility of wastewater surveillance has yet to be fully realized at a population level, it has the potential to be cost-efficient and complementary to individual testing efforts.⁷

PUBLIC HEALTH SIGNIFICANCE

Community interventions were built on successful efforts to mitigate infectious disease transmission on a university campus²—comporting with the highly interconnected nature of university and city life. Building partnerships with organizations, government, and key stakeholder groups while combining epidemiological and health behavior change approaches was achievable and likely generalizable to other college towns and to other types of communities. Our multimodal COVID-19 community intervention program resulted in favorable changes in key self-reported health behaviors (e.g., asymptomatic testing and vaccination). Case positivity proportion was much lower in Davis compared with other areas. Building public health infrastructure with such programs may be pivotal in promoting health in the postpandemic era.

POSTPUBLICATION UPDATE

October 2, 2025: Since initial publication, author Charlotte L. Bergheimer changed their name to Charlotte L. Kerber. The byline, citation, “About the Authors” section, and the “Contributors” section have been updated to reflect this change.