Clinical and epidemiologic characteristics associated with dengue fever in 2011–2016 in Bang Phae district, Ratchaburi province, Thailand

Abstract

Background Dengue is a major public health problem in Thailand, but data are often focused on certain dengue-endemic areas. Methods: To better understand dengue epidemiology and clinical characteristics in Thailand, a fever surveillance study was conducted among patients aged 1–55 years, who presented with non-localized febrile illness at Bang Phae Community Hospital in Ratchaburi province, Thailand from October 2011 to September 2016. Results Among 951 febrile episodes, 130 were dengue-confirmed. Individuals aged 10–14 years were mostly affected, followed by those 15–19 years-of-age, with about 15% of dengue-confirmed cases from adults 25 years and older. There were annual peaks of dengue occurrence between June-November. Most prevalent serotype in circulation was DENV-2 in 2012, DENV-3 in 2014, and DENV-4 & -3 in 2015. Among dengue cases, 65% were accurately detected using the dengue NS1 RDT. Detection rate was similar between secondary and primary dengue cases where 66% of secondary vs. 60% of primary dengue cases had positive results on the NS1 RDT. Among dengue cases, 66% were clinically diagnosed with suspected dengue or DHF, prior to lab confirmation. Dengue was positively associated with rash, headache, hematemesis and alterations to consciousness, when compared to non-dengue. Dengue patients were 10.6 times more likely to be hospitalized, compared to non-dengue cases. Among dengue cases, 95 were secondary and 35 were primary infections. There were 8 suspected DHF cases and all were identified to be secondary dengue. Secondary dengue cases were 3.5 times more likely to be hospitalized compared to primary dengue cases. Although the majority of our dengue-positive patients were secondary dengue cases, with few patients showing manifestations of DHF, our dengue cases were mostly mild disease. Even among children < 10 years-of-age, 61% had secondary infection and the rate of secondary infection increased with age. Conclusion While the majority of dengue-confirmed cases were children, almost three-quarters of dengue-confirmed cases in this study were secondary dengue. Our study results consistent with previous data from the country confirm the hyperendemic transmission of DENV in Thailand, even in the non-epidemic years. With various interventions becoming available for dengue prevention and control, including dengue vaccines, decision-making on future implementation strategies should be based on such burden of disease data.

Dengue virus seroprevalence study in Bangphae district, Ratchaburi, Thailand: A cohort study in 2012-2015

“…These subjects who sought care also reported that they had a previous dengue infection over the interval, but this was not verified with information on medical charts. In the same catchment population in Bangphae district during an overlapping study period, there was a facility-based fever surveillance study [ 21 ]. These serosurvey subjects who sought care for febrile illness at BPCH during the interval between serosurvey visits were enrolled in our fever surveillance study and tested for acute dengue fever (with IgM/IgG ELISA and RT-PCR) [ 21 ].…”

“…In the same catchment population in Bangphae district during an overlapping study period, there was a facility-based fever surveillance study [ 21 ]. These serosurvey subjects who sought care for febrile illness at BPCH during the interval between serosurvey visits were enrolled in our fever surveillance study and tested for acute dengue fever (with IgM/IgG ELISA and RT-PCR) [ 21 ]. There were few of these serosurvey subjects who were captured in the surveillance ( Table 1 ).…”

“…In the same target study area in Bangphae during an overlapping study period, we also conducted a fever surveillance study, with a separate consenting process, enrolling patients aged 1–55 years who presented with non-localized febrile illness at Bang Phae Community Hospital (BPCH) in Ratchaburi province, from October 2011 to September 2016 [ 21 ]. Paired blood samples were taken 10–21 days apart from enrolled patients and collected acute/convalescent sera were tested with in-house ELISA dengue IgM/IgG [ 21 , 22 ], and a subset (all of the serological positive cases with a small number of serological negative cases) with RT-PCR [ 21 , 23 ].…”

“…Serosurvey subjects who sought care for febrile illness at BPCH during the interval between bleeds were enrolled in the surveillance and tested for acute dengue fever. The surveillance study data were presented separately [ 21 ]. These numbers represent those serosurvey subjects who had fever, participated in the surveillance, and were RT-PCR-confirmed with dengue in the surveillance.…”

Lab-scale characterization and semi-field trials of Wolbachia Strain wAlbB in a Taiwan Wolbachia introgressed Ae. aegypti strain

“…albopictus , and widely used and highly safe vaccines and antiviral treatments currently exist [ 2 ]. In addition to interventions targeting the disease via the vector, such as insecticide application, clinical management can also be used to intervene in the spread of the disease [ 4 ]. However, existing strategies have proven insufficient for dealing with the significant increase in cases of dengue fever reported worldwide [ 5 ].…”