Hyperendemicity associated with increased dengue burden

Abstract

Over 105 million dengue infections are estimated to occur annually. Understanding the disease dynamics of dengue is often difficult due to multiple strains circulating within a population. Interactions between dengue serotype dynamics may result in complex cross-immunity dynamics at the population level and create difficulties in terms of formulating intervention strategies for the disease. In this study, a nationally representative 16-year time series with over 43 000 serotyped dengue infections was used to infer the long-run effects of between and within strain interactions and their impacts on past outbreaks. We used a novel identification strategy incorporating sign-identified Bayesian vector autoregressions, using structural impulse responses, historical decompositions and counterfactual analysis to conduct inference on dengue dynamics post-estimation. We found that on the population level: (i) across-serotype interactions on the population level were highly persistent, with a one time increase in any other serotype associated with long run decreases in the serotype of interest (range: 0.5–2.5 years) and (ii) over 38.7% of dengue cases of any serotype were associated with across-serotype interactions. The findings in this paper will substantially impact public health policy interventions with respect to dengue.

Fine-scale estimation of effective reproduction numbers for dengue surveillance

“…Also, we did not account for variation in the transmissibility of each of the four dengue serotypes that are in circulation in Singapore [55], which might depend on other factors such as levels of population immunity and/or cross-immunity to each serotype. However, given that these dynamics are likely long-term trends, they are unlikely to affect estimates as effective reproduction numbers are short-term metrics [56]. Lastly, while we revealed significant spatial autocorrelation in R t estimates, these were not explicitly incorporated in our estimates, due to the limitations in the utilised functional form of R t .…”

Assessing the efficacy of male Wolbachia-infected mosquito deployments to reduce dengue incidence in Singapore: study protocol for a cluster-randomized controlled trial

“…Singapore is an equatorial city-state in Southeast Asia where Ae. aegypti is ubiquitous and dengue is hyperendemic [ 26 , 27 ]. Besides dengue, the country has also reported sporadic chikungunya infections since 2013, following an outbreak in 2008 and 2013 [ 28 , 29 ] and experienced a Zika outbreak in 2016 [ 30 , 31 ].…”

Review of Importance of Weather and Environmental Variables in Agent-Based Arbovirus Models

“…Furthermore, the active circulation of multi-serotypes of dengue make it hyperendemic in many countries. It is posited that, decrease in cross-immunity is among the contributory factor to large dengue outbreaks [ 11 ]. Outbreaks happening in new areas for the first time mostly tend to involve immunologically naïve populations resulting into high rates of attack [ 11 ].…”

“…It is posited that, decrease in cross-immunity is among the contributory factor to large dengue outbreaks [ 11 ]. Outbreaks happening in new areas for the first time mostly tend to involve immunologically naïve populations resulting into high rates of attack [ 11 ]. Marchi, Trombetta, and Montomoli [ 10 ] report that “the greatest health risk of arbovirus emergence comes from extensive tropical urbanization and colonization of this expanding habitat by the highly anthropophilic mosquito, Aedes aegypti , together with the recent invasion into the Americas, Europe and Africa of Aedes albopictus that could enhance transmission of these viruses in temperate regions”.…”

“…Mahmood et al [ 14 ] reported that 3.98 billion people in 128 countries are at risk of contracting dengue [ 13 , 26 , 27 ]. An annual estimate of over 105 million dengue cases is reported [ 11 , 28 ]. A study by Cattarino et al [ 28 ] further estimates that most dengue disease burden was concentrated in South and Southeast Asia valued to about 58%, 26% occurring in SSA mostly concentrated in Central and Eastern Africa, and Latin America had an estimation of 16% of the global burden.…”