Comparison of National Vulnerability Indices Used by the Centers for Disease Control and Prevention for the COVID-19 Response

Abstract

Objective: Vulnerability indices use quantitative indicators and geospatial data to examine the level of vulnerability to morbidity in a community. The Centers for Disease Control and Prevention (CDC) uses 3 indices for the COVID-19 response: the CDC Social Vulnerability Index (CDC-SVI), the US COVID-19 Community Vulnerability Index (CCVI), and the Pandemic Vulnerability Index (PVI). The objective of this review was to describe these tools and explain the similarities and differences between them.

Methods: We described the 3 indices, outlined the underlying data sources and metrics for each, and discussed their use by CDC for the COVID-19 response. We compared the percentile score for each county for each index by calculating Spearman correlation coefficients (Spearman ρ).

Results: These indices have some, but not all, component metrics in common. The CDC-SVI is a validated metric that estimates social vulnerability, which comprises the underlying population-level characteristics that influence differences in health risk among communities. To address risk specific to the COVID-19 pandemic, the CCVI and PVI build on the CDC-SVI and include additional variables. The 3 indices were highly correlated. Spearman ρ for comparisons between the CDC-SVI score and the CCVI and between the CCVI and the PVI score was 0.83. Spearman ρ for the comparison between the CDC-SVI score and PVI score was 0.73.

Conclusion: The indices can empower local and state public health officials with additional information to focus resources and interventions on disproportionately affected populations to combat the ongoing pandemic and plan for future pandemics.

Keywords: COVID-19; GIS; geographic information systems; social vulnerability index; vulnerability.

Figure 1.

Centers for Disease Control and Prevention (CDC) 2018 Social Vulnerability Index, by US county, generated February 24, 2021. Social vulnerability refers to the negative effects on communities caused by external stresses on human health. Data were mapped by using quartile classification. Data source: CDC.

Figure 2.

The COVID-19 Community Vulnerability Index, by US county, generated February 24, 2021. Community vulnerability is defined as a limited ability to mitigate, treat, and delay transmission of virus and not withstand its secondary effects on health, economic, and social outcomes. Data were mapped by using quartile classification. Data source: Surgo Ventures.

Figure 3.

The National Institutes of Health COVID-19 Pandemic Vulnerability Index, by US county, generated February 24, 2021. Pandemic vulnerability refers to the susceptibility of populations to the pandemic and lack of coping resources to alleviate its impact. Data were mapped by using quartile classification. Data source: National Institute for Environmental Health Sciences.

Figure 4.

Comparison of percentile scores of 3 vulnerability indices for each US county, 2021. Vulnerability refers to the potential negative effects on communities caused by external stresses on human health, such as disease outbreaks or natural disasters. Each dot represents a US county. Percentile score for each county for each index was compared by calculating Spearman correlation coefficients. A, Comparison of CCVI and CDC-SVI. B, Comparison of PVI and CDC-SVI. C, Comparison of PVI and CCVI. Abbreviations and data sources: CCVI, US COVID-19 Community Vulnerability Index; CDC-SVI, Centers for Disease Control and Prevention Social Vulnerability Index; PVI, Pandemic Vulnerability Index (Model 11.2.1), accessed February 24, 2021.