Dataset Information

Differences in Transmission and Disease Severity Between 2 Successive Waves of Chikungunya.

ABSTRACT:

Background

Chikungunya, an arboviral disease, caused massive epidemics in Central and South America in 2014-2016. In a prospective pediatric cohort study, we examined the introduction of chikungunya in a naive population and investigated transmission and clinical characteristics.

Methods

Children presenting to the study health center with a chikungunya-like illness or undifferentiated fever were tested for chikungunya virus (CHIKV) infection by reverse transcriptase-polymerase chain reaction (RT-PCR) and serological assays. Inapparent CHIKV infections in the intervening year were determined by seroconversion in healthy blood samples collected annually.

Results

A total of 4353 children participated in the cohort study from March 2014 to February 2016 during the 2 epidemic waves of chikungunya. A total of 539 cases of chikungunya were documented, for an incidence rate of 80.2 cases per 1000 person-years (95% confidence interval [CI]: 73.7, 87.2); and a total of 893 CHIKV infections were documented, for an incidence rate of 137.1 infections per 1000 person-years (95% CI: 128.4, 146.4). The seroprevalence of anti-CHIKV antibodies increased linearly with age, with seroprevalence of >45% in 14-year-old children at the end of Epidemic 2. Symptom presentation varied between the epidemics, with Epidemic 2 exhibiting both a higher symptomatic-to-inapparent ratio (1:1.20 in Epidemic 1 vs. 1:0.65 in Epidemic 2) and more severe clinical presentation among cases. The mean reproduction number was also greater in Epidemic 2 than in Epidemic 1.

Conclusions

The intensity of transmission and severity of clinical presentation varied between the 2 epidemics, with higher transmission intensity associated with greater disease severity.

SUBMITTER: Gordon A

PROVIDER: S-EPMC6233685 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Publications

Differences in Transmission and Disease Severity Between 2 Successive Waves of Chikungunya.

Gordon Aubree A Gresh Lionel L Ojeda Sergio S Chowell Gerardo G Gonzalez Karla K Sanchez Nery N Saborio Saira S Mercado Juan Carlos JC Kuan Guillermina G Balmaseda Angel A Harris Eva E

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 20181101 11

<h4>Background</h4>Chikungunya, an arboviral disease, caused massive epidemics in Central and South America in 2014-2016. In a prospective pediatric cohort study, we examined the introduction of chikungunya in a naive population and investigated transmission and clinical characteristics.<h4>Methods</h4>Children presenting to the study health center with a chikungunya-like illness or undifferentiated fever were tested for chikungunya virus (CHIKV) infection by reverse transcriptase-polymerase cha ...[more]

PMID: 29697796

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Dataset Information

Differences in Transmission and Disease Severity Between 2 Successive Waves of Chikungunya.

Background

Methods

Results

Conclusions

Publications

Differences in Transmission and Disease Severity Between 2 Successive Waves of Chikungunya.

Similar Datasets

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