Study of viremic profile in febrile specimens of chikungunya in Bandung, Indonesia.

ABSTRACT

BACKGROUND: Data regarding the viremia profile of chikungunya virus (CHIKV) infected patients especially during the pre-febrile period is limited. OBJECTIVE: To obtain virological kinetic data on CHIKV infections. STUDY DESIGN: A two-week community observation for dengue transmission was conducted in Bandung, Indonesia, from 2005 to 2009. Acute specimens from non-dengue febrile patients were screened by pan-alphavirus conventional RT-PCR. The positives were confirmed for CHIKV RNA by a specific RT-PCR followed by sequencing. Simultaneously these specimens were also cultured in Vero cells and tested for anti-CHIK IgM MAC-ELISA. All the available serial specimens,including the pre-febrile specimens, from confirmed CHIK cases, were tested by virus isolation, RT-PCR, qRT-PCR, and CHIK IgM ELISA. RESULTS: There were five laboratory confirmed CHIK cases identified and studied. Among these, viremia was determined to extend from as early as 6 days prior to until 13 days post fever onset. Quantitative RT-PCR showed viremia peaked at or near onset of illness. CONCLUSION: In this study, individuals were identified with viremia prior to fever onset and extending beyond the febrile phase. This extended viremic phase has the potential to impact transmission dynamics and thus the public health response to CHIK outbreaks.