A community-based prospective cohort study of dengue viral infection in Malaysia: the study protocol

Abstract

BackgroundGlobally, dengue infections constitute a significant public health burden. In recent decades, Malaysia has become a dengue hyper-endemic country with the co-circulation of the four dengue virus serotypes. The cyclical dominance of sub-types contributes to a pattern of major outbreaks. The consequences can be observed in the rising incidence of reported dengue cases and dengue related deaths. Understanding the complex interaction of the dengue virus, its human hosts and the mosquito vectors at the community level may help develop strategies for addressing the problem.MethodsA prospective cohort study will be conducted in Segamat district of Johor State in Peninsular Malaysia. Researchers received approval from the Malaysian Medical Research Ethics Committee and Monash University Human Research Ethics Committee. The study will be conducted at a Malaysian based health and demographic surveillance site over a 1 year period in three different settings (urban, semi-urban and rural). The study will recruit healthy adults (male and female) aged 18 years and over, from three ethnic groups (Malay, Chinese and Indian). The sample size calculated using the Fleiss method with continuity correction is 333. Sero-surveillance of participants will be undertaken to identify asymptomatic, otherwise healthy cases; cases with dengue fever who are managed as out-patients; and cases with dengue fever admitted to a hospital. A genetic analysis of the participants will be undertaken to determine whether there is a relationship between genetic predisposition and disease severity. A detailed medical history, past history of dengue infection, vaccination history against other flaviviruses such as Japanese encephalitis and Yellow fever, and the family history of dengue infection will also be collected. In addition, a mosquito surveillance will be carried out simultaneously in recruitment areas to determine the molecular taxonomy of circulating vectors.DiscussionThe research findings will estimate the burden of asymptomatic and symptomatic dengue at the community level. It will also examine the relationship between virus serotypes and host genotypes, and the association of the clinical manifestation of the early phase with the entire course of illness.Electronic supplementary materialThe online version of this article (doi:10.1186/s40249-016-0172-3) contains supplementary material, which is available to authorized users.

Seroprevalence of dengue among healthy adults in a rural community in Southern Malaysia: a pilot study

“…Participants were recruited from three localities (villages) within the Sungai Segamat subdistrict representing rural, urban, and semi-urban communities. Based on notified dengue cases, the three study localities had been identified as the dengue epicenter in the Sungai Segamat subdistrict since 2009 [ 11 ].…”

“…The comprehensive study protocol has previously been described by Jahan et al [ 11 ], and is briefly described here. Essentially, this study extended slightly over a one-year period and consisted of four phases of data and blood collection.…”

“…The target sample was based on a sample size calculation of 333 [ 11 ]. An open invitation was sent to eligible participants through flyers dropped to their homes and was followed up with visits by SEACO data collectors to confirm participation and provide information sheets ahead of consent.…”

“…Following the interview, a 5 ml blood sample was drawn from each participant by trained phlebotomists and collected in BD Vacutainer® blood collection tubes (Becton Dickinson, Franklin Lakes, NJ, USA), using a clot activator and gel separator. Proper storage and transportation of these blood samples from the community hall to the laboratory followed a standard protocol, as described elsewhere [ 11 ].…”

Seroprevalence and factors associated with IgG anti‐DENV positivity in blood donors in Burkina Faso during the 2016 dengue outbreak and implications for blood supply

“…Globally, dengue infections constitute a significant public health burden. Nearly two‐thirds of the global population is at risk, mainly in African, Asian and American inter‐tropical developing countries. In the last half century, the prevalence of the dengue virus (DENV) has increased dramatically (up to 30%) worldwide, especially in Sub‐Saharan Africa .…”