Role of Aedes aegypti and Aedes albopictus during the 2011 dengue fever epidemics in Hanoi, Vietnam

Objective: To record the human cases of dengue fever(DF) and investigate the Aedes mosquito species circulating during the Hanoi 2011 DF epidemics. Methods: 24 different outbreak points were recorded in 8 districts between August and December 2011. Results: 140 patients were hospitalized following dengue diagnostic with a predominance of males(59.3%) and the 15-34 age class. Only DENV-1(11.27%) and DENV-2(88.73%) serotypes were detected in human samples. Mosquito sampling performed in and around patients households revealed the predominance of Aedes aegypti(95.15%) versus Aedes albopictus(4.85%). There is a positive correlation between the population density of Aedes aegypti and the number of human cases and duration of outbreaks. Conclusions: This was not observed for Aedes albopictus. 3 pools of Aedes aegypti were positive with dengue virus, two with DENV-1 and one with DENV-2.

Surveillance of dengue and chikungunya infection in Dong Thap,Vietnam:A 13-month study

Objective:To establish a surveillance in Dong Thap,at the border with Cambodia by assessing the presence of DHNV serotypes and CHIKV among patients hospitalized at Dong Thap general hospital.Methods:Cross-sectional descriptive analysis was conducted on a cohort of 131 patients hospitalized with acute fever and symptoms compatible with dengue or chikungunya.The study was conducted from January 2012 to February 2013.The full clinical picture was established as well as serological and molecular detection.Serological analysis was sequentially performed on blood samples collected on admission and an average of seven days after admission.The detection of IgM antibody to DENV was performed by IgM capture ELTSA and the detection of DENV and CHIKV RNA was done by reverse-transcription multiplex PCR.Results:101 patients out of 131(77%) were confirmed with dengue.All four dengue serotypes were detected with a predominance of DENV2 and DENV4.No chikungunya infection was detected although reported in neighboring Cambodia.A differential efficiency of serological dengue detection was observed.Efficiency was 29%upon admission and 53%after seven days on the same patients.30 patients out of 131(23%) were negative with both DENV and CHIKV.Conclusions:Dengue is at risk of being underestimated and chikungunya is not systematically detected.Changes in detection and surveillance procedures are therefore discussed to increase efficiency of dengue detection and continue the monitoring the emergence of CHIKV in Dong Thap province and in Vietnam.

HIV-1 Assembly, Release and Maturation

Late steps of HIV-1 life cycle are determinant for optimal dissemination of the virus to new target cells. These steps include assembly of structural precursors, budding of the new particle and maturation into fully infectious virions. Each step is finely tuned and timely regulated to allow the appropriate assembly of structural components, the efficient recruitment of viral and cell partners and the timely regulated proteolytic processing of the protein precursors. Despite the huge number of studies devoted to the definition of molecular mechanisms regulating these steps, a number of question remains to be answered before they are clearly apprehended. The elucidation of the role played by each viral proteins, nucleic acids as well as host-encoded factors will provide new clues in the understanding of the retroviral assembly/maturation process and will allow further development of new antiviral compounds. This review reports the most recent progress as well as the questions that remain to be answered in the field of HIV-1 assembly, release and maturation. Finally, we also describe the data available on the design and use of new antiretroviral drugs targeting these specific steps of the retroviral replication.