High Circulating Levels of the Dengue Virus Nonstructural Protein NS1 Early in Dengue Illness Correlate with the Development of Dengue Hemorrhagic Fever

Abstract

Infection with any 1 of 4 dengue viruses produces a spectrum of clinical illness ranging from a mild undifferentiated febrile illness to dengue fever (DF) to dengue hemorrhagic fever (DHF), a potentially life-threatening disease. The morbidity and mortality of DHF can be reduced by early hospitalization and careful supportive care. To determine its usefulness as a predictor of DHF, plasma levels of the secreted dengue virus nonstructural protein NS1 (sNS1) were measured daily in 32 children with dengue-2 virus infections participating in a prospective, hospital-based study. Free sNS1 levels in plasma correlated with viremia levels and were higher in patients with DHF than in those with DF. An elevated free sNS1 level (> or =600 ng/mL) within 72 h of illness onset identified patients at risk for developing DHF.

Prevalencia y curso clínico de la infección por dengue en adultos mayores con cuadro febril agudo en un hospital de alta complejidad en Cali, Colombia

“…Se ha determinado, asimismo, que tanto los niveles de carga viral como de antígeno NS1 se correlacionan con el daño endotelial y las hemorragias graves en el dengue (25,(30)(31)(32).…”

The pathogenesis of dengue

“…80 The significance of these observations with the independent observation that early NS1 concentrations in blood are positively associated with disease severity are not yet clear, but are consistent with a role for NS1 and complement in pathogenesis . 81,82 Finally, it is plausible that the low levels of complement observed in severe dengue are merely a marker of a severe systemic disease rather than an indicator of their role in capillary permeability.…”

Evaluation of Nonstructural 1 Antigen Assays for the Diagnosis and Surveillance of Dengue in Singapore

“…The possibility of anti-NS1 antibodies resulting from a previous infection in quenching the NS1 antigen of a current infection has been discussed to explain this observation (Valdes et al 2000, Libraty et al 2002, Koraka et al 2003. Nevertheless, NS1 assay was found to have around 50% sensitivity among secondary dengue infections in Singapore, where approximately 45% of dengue cases are secondary infections (Low et al 2006).…”