Dataset Information

Long-term and seasonal dynamics of dengue in Iquitos, Peru.

ABSTRACT:

Introduction

Long-term disease surveillance data provide a basis for studying drivers of pathogen transmission dynamics. Dengue is a mosquito-borne disease caused by four distinct, but related, viruses (DENV-1-4) that potentially affect over half the world's population. Dengue incidence varies seasonally and on longer time scales, presumably driven by the interaction of climate and host susceptibility. Precise understanding of dengue dynamics is constrained, however, by the relative paucity of laboratory-confirmed longitudinal data.

Methods

We studied 10 years (2000-2010) of laboratory-confirmed, clinic-based surveillance data collected in Iquitos, Peru. We characterized inter and intra-annual patterns of dengue dynamics on a weekly time scale using wavelet analysis. We explored the relationships of case counts to climatic variables with cross-correlation maps on annual and trimester bases.

Findings

Transmission was dominated by single serotypes, first DENV-3 (2001-2007) then DENV-4 (2008-2010). After 2003, incidence fluctuated inter-annually with outbreaks usually occurring between October and April. We detected a strong positive autocorrelation in case counts at a lag of ? 70 weeks, indicating a shift in the timing of peak incidence year-to-year. All climatic variables showed modest seasonality and correlated weakly with the number of reported dengue cases across a range of time lags. Cases were reduced after citywide insecticide fumigation if conducted early in the transmission season.

Conclusions

Dengue case counts peaked seasonally despite limited intra-annual variation in climate conditions. Contrary to expectations for this mosquito-borne disease, no climatic variable considered exhibited a strong relationship with transmission. Vector control operations did, however, appear to have a significant impact on transmission some years. Our results indicate that a complicated interplay of factors underlie DENV transmission in contexts such as Iquitos.

SUBMITTER: Stoddard ST

PROVIDER: S-EPMC4102451 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Publications

Long-term and seasonal dynamics of dengue in Iquitos, Peru.

Stoddard Steven T ST Wearing Helen J HJ Reiner Robert C RC Morrison Amy C AC Astete Helvio H Vilcarromero Stalin S Alvarez Carlos C Ramal-Asayag Cesar C Sihuincha Moises M Rocha Claudio C Halsey Eric S ES Scott Thomas W TW Kochel Tadeusz J TJ Forshey Brett M BM

PLoS neglected tropical diseases 20140717 7

<h4>Introduction</h4>Long-term disease surveillance data provide a basis for studying drivers of pathogen transmission dynamics. Dengue is a mosquito-borne disease caused by four distinct, but related, viruses (DENV-1-4) that potentially affect over half the world's population. Dengue incidence varies seasonally and on longer time scales, presumably driven by the interaction of climate and host susceptibility. Precise understanding of dengue dynamics is constrained, however, by the relative pauc ...[more]

PMID: 25033412

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Dataset Information

Long-term and seasonal dynamics of dengue in Iquitos, Peru.

Introduction

Methods

Findings

Conclusions

Publications

Long-term and seasonal dynamics of dengue in Iquitos, Peru.

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