Serum levels of soluble vascular cell adhesion molecules may correlate with the severity of dengue virus-1 infection in adults.

The damage of vascular endothelial cells has been speculated to be involved in the pathogenesis of dengue virus (DENV) infection. However, little is known about the role of soluble vascular cell adhesion molecule-1 (sVCAM-1) in predicting the severity of dengue infection in adults. In this study, 51 adults with DENV-1 infection (21 with severe dengue and 30 with dengue fever (DF) were included, and their serum levels of sVCAM-1 and other parameters were determined. The results indicated that the levels of sVCAM-1 were elevated on days 1-3 to 16.75 (11.55-34.74) ng/mL in the severe dengue patients. These levels increased rapidly to peak values of 43.53 (37.15-47.02) ng/mL on days 10-12 and then declined; however, the values were maintained at a high level (38.07 (26.06-39.63) ng/mL). Other parameters, including reduced platelet (PLT) counts, neutrophil (NEU) counts and increased levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine kinase (CK), were also observed in the severe dengue group but not in the DF group. The levels of cytokines, such as interleukin (IL)-6, IL-10, interferon γ (IFNγ), and tumor necrosis factor α (TNF-α), were transiently increased in the severe dengue patients. Among the aforementioned parameters, only sVCAM-1 levels were significantly elevated earlier and more persistently in the severe dengue patients than in the DF patients. sVCAM-1 positively correlated with the levels of ALT, AST, LDH, TNF-α, and IL-6 and negatively correlated with the levels of PLT, NEU, and viremia. Notably, the high levels of sVCAM-1 were closely associated with the severe dengue patients. In conclusion, sVCAM-1 may be a superior indicator for monitoring the severity of dengue.

Co-circulation of two genotypes of dengue virus serotype 3 in Guangzhou, China, 2009.

Dengue is emerging as the most important mosquito borne viral disease in the world. In mainland China, sporadic and large outbreaks of dengue illness caused by the four serotypes of dengue virus (DENV-1 to DENV-4) have been well documented. Guangdong province is the major affected area in China, and DENV-1 has dominantly circulated in Guangdong for a long time. In this study, a family cluster of DENV-3 infection in Guangzhou was described. Three cases were diagnosed as dengue fever based on clinical manifestation, serological and RT-PCR assays. Two DENV-3 strains were isolated in C6/36 cells and the complete genome sequences were determined. Phylogenetic analysis revealed that the new DENV-3 isolates from the family cluster were grouped within genotype III. Considering the fact that several DENV-3 strains within genotype V were also identified in Guangzhou in 2009, at least two genotypes of DENV-3 co-circulated in Guangzhou. Careful investigation and virological analysis should be warranted in the future.