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Multiplexed Isothermal Amplification Based Diagnostic Platform to Detect Zika, Chikungunya, and Dengue 1
Published on: March 13, 2018
Epidemics of chikungunya, Zika, and COVID-19 reveal bias in case-based mapping
Fausto Andres Bustos Carrillo1, Brenda Lopez Mercado2, Jairo Carey Monterrey2
1University of California, Berkeley, Berkeley, California, USA.
Abstract:
Accurate tracing of epidemic spread over space enables effective control measures. We examined three metrics of infection and disease in a pediatric cohort (N≈3,000) over two chikungunya and one Zika epidemic, and in a household cohort (N=1,793) over one COVID-19 epidemic in Managua, Nicaragua. We compared spatial incidence rates (cases/total population), infection risks (infections/total population), and disease risks (cases/infected population). We used generalized additive and mixed-effects models, Kulldorf's spatial scan statistic, and intracluster correlation coefficients. Across different analyses and all epidemics, incidence rates considerably underestimated infection and disease risks, producing large and spatially non-uniform biases distinct from biases due to incomplete case ascertainment. Infection and disease risks exhibited distinct spatial patterns, and incidence clusters inconsistently identified areas of either risk. While incidence rates are commonly used to infer infection and disease risk in a population, we find that this can induce substantial biases and adversely impact policies to control epidemics.
Insights
Incidence rates often underestimate epidemic risks. This study reveals significant spatial biases, impacting effective disease control strategies and public health policies during outbreaks.
Area of Science:
- Epidemiology
- Public Health
- Spatial Analysis
Background:
- Accurate spatial tracing of epidemic spread is crucial for effective control measures.
- Traditional incidence rates may not fully capture the true extent of infection and disease risks.
- Understanding spatial patterns of epidemics informs public health interventions.
Approach:
- Compared spatial incidence rates, infection risks, and disease risks in pediatric and household cohorts during chikungunya, Zika, and COVID-19 epidemics in Managua, Nicaragua.
- Employed generalized additive and mixed-effects models, Kulldorf's spatial scan statistic, and intracluster correlation coefficients.
- Analyzed data from approximately 3,000 children and 1,793 individuals in households.
Key Points:
- Incidence rates consistently underestimated infection and disease risks across multiple epidemics.
- Significant, spatially non-uniform biases were observed, distinct from ascertainment issues.
- Infection and disease risks displayed different spatial patterns, with incidence clusters not reliably indicating high-risk areas.
Conclusions:
- Relying solely on incidence rates can lead to substantial biases in assessing epidemic spread and risk.
- These biases can adversely affect the development and implementation of epidemic control policies.
- Accurate risk assessment requires metrics beyond simple incidence rates for effective public health management.
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