Evaluation of the Diagnostic Utility of the Traditional and Revised WHO Dengue Case Definitions

Abstract

Dengue, a mosquito-borne viral illness, is a major public health problem worldwide, and its incidence continues to increase. In 2009, the World Health Organization published guidelines that included a revision of the dengue case definition. Compared to the traditional definition, the revised case definition relies more on signs than on symptoms, making it more applicable to young children. We evaluated the diagnostic utility of both case definitions in two studies of pediatric dengue in Managua, Nicaragua. In a community-based cohort study, we included data from 3,407 suspected dengue cases, of which 476 were laboratory-confirmed. In the second study, we collected information from 1,160 participants recruited at the national pediatric reference hospital (723 laboratory-confirmed). In the cohort study, the traditional definition had 89.3% sensitivity and 43.1% specificity, while the revised definition yielded similar sensitivity (86.6%) and higher specificity (55.2%, p<0.001). In the hospital study, the traditional case definition yielded 96.7% sensitivity and 22.0% specificity, whereas the revised case definition had higher sensitivity (99.3%, p<0.001) but lower specificity (8.5%, p<0.001). We then evaluated the performance of two diagnostic models based on the signs/symptoms included in each definition by analyzing the effect of increasing numbers of signs/symptoms on the sensitivity and specificity of case capture. Receiver operating characteristic analysis showed a slightly better performance for the revised model in both studies. Interestingly, despite containing less symptoms that cannot be readily expressed by children aged less than 4 years, the revised definition did not perform better in this age group. Overall, our results indicate that both case definitions have similar capacity to diagnose dengue. Owing to their high sensitivity and low specificity, they should be primarily used for screening purposes. However, in a primary care setting, neither of the case definitions performed well as a screening test in younger children.

Evaluation of the WHO classification of dengue disease severity during an epidemic in 2011 in the state of Ceará, Brazil

“…These data are similar to recent reports from Nicaragua ( Narvaez et al 2011 , Gutiérrez et al. 2013 ) and are the first evidence from Brazil.…”

Multicountry Prospective Clinical Evaluation of Two Enzyme-Linked Immunosorbent Assays and Two Rapid Diagnostic Tests for Diagnosing Dengue Fever

“…Thus, these techniques are not only time-consuming but also labor-intensive, requiring trained personnel and specialized equipment. A delay in obtaining laboratory results can hinder evidence-based patient care decisions, leading physicians to rely on symptomatic diagnosis, the accuracy of which varies with physician experience (23)(24)(25)(26)(27).…”

Evaluation of the World Health Organization 2009 classification of dengue severity in autopsied individuals, during the epidemics of 2011 and 2012 in Brazil

“…The WHO 2009 classifi cation proposes that countries calculate the fatality from SD by dividing the number of deaths from SD by the population of each region, and then multiplying the obtained value by 1,000. The adoption of the WHO 2009 classifi cation should improve the comparison of dengue fatality rates among different countries because it captures severe cases (8) (15) (22) . It is believed that if this indicator is used, the fatality rates from dengue can be easily compared among different regions, considering population size and the impact of the disease in each region.…”