Dengue diagnosis, advances and challenges

Abstract

Dengue diagnosis was one of the topics discussed at the symposium 'The Global Threat of Dengue - Desperately Seeking Solutions' organized during the 10th International Congress of Infectious Diseases held in Singapore in 2002. In this paper, a review is presented focusing on the main advances, problems and challenges of dengue diagnosis.IgM capture ELISA, virus isolation in mosquito cell lines and live mosquitoes, dengue specific monoclonal antibodies and PCR have all represented major advances in dengue diagnosis. However, an appropriate rapid, early and accessible diagnostic method useful both for epidemiological surveillance and clinical diagnosis is still needed. Also, tools that suggest a prognosis allowing for better management are also needed. Finally, laboratory infrastructure, technical expertise and research capacity must be improved in endemic countries in order to positively influence dengue surveillance, clinical case management and the development of new approaches to dengue control.

The pathogenesis of dengue

“…21,22 In many settings DEN is diagnosed clinically; however the features of early infection are non-specific and mimic those of other febrile illnesses. [23][24][25] An early diagnosis would assist in patient triage and will have an increasingly important role as therapeutic drugs, e.g. anti-virals, become available for DEN.…”

Single-tube nested PCR using immobilized internal primers for the identification of dengue virus serotypes

“…Molecular techniques based on the detection of genomic sequences by reverse transcription (RT)-PCR, nested PCR, and real-time PCR allow for rapid diagnosis of dengue virus serotypes and have replaced virus isolation as the new standard method for the detection of dengue virus in acute-phase serum samples (Guzman and Kouri, 2004). One of these, the two-step nested RT-PCR (RT-NPCR) approach, is routinely employed in laboratories worldwide.…”

“…Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. severe clinical forms such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) (Guzman and Kouri, 2004). In recent years, dengue virus infection has emerged as a major public health problem, with expanding geographical distribution and increasing epidemic activity (Guha-Sapir and Schimmer, 2005).…”

“…Epidemiological studies have shown that secondary infection is a major risk for DHF and DSS (Rothman, 2004). Thus, discrimination between primary and secondary dengue virus infection and current infection is important for both patient management and epidemiological investigations.Because of the extensive cross-reactivity among flaviviruses, and the fact that IgM antibody responses are often low during the first 5 days of symptoms, identification of the infecting virus by serology during the acute phase of the infection is not possible in many cases in which flaviviruses are circulating (Guzman and Kouri, 2004). Molecular techniques based on the detection of genomic sequences by reverse transcription (RT)-PCR, nested PCR, and real-time PCR allow for rapid diagnosis of dengue virus serotypes and have replaced virus isolation as the new standard method for the detection of dengue virus in acute-phase serum samples (Guzman and Kouri, 2004).…”

“…One of these, the two-step nested RT-PCR (RT-NPCR) approach, is routinely employed in laboratories worldwide. Identification and typing of dengue virus serotypes is achieved by RT-PCR followed by nested PCR, using complex-and serotypespecific primers, respectively (Guzman and Kouri, 2004). Although real-time PCR offers the additional advantage of providing quantitation of the viral burden (Anwar et al, 2006;Chien et al, 2006;Kong et al, 2006), its use is still limited to well-structured reference laboratories.…”