Epidemiology Study of Dengue Virus In Surabaya, Bogor, and Bangkalan, Indonesia 2008-2018

Dengue virus (DENV) is mosquito-borne viral diseases, transmitted by the vector mosquitoes such as Aedes sp. Infection with four serotypes of DENV-1 to 4. Indonesia, dengue haemorrhagic fever (DHF) was first recognized in 1968 in the cities of Jakarta and Surabaya. In 2007, we started DENV surveillance in Surabaya supported by the joined program of the Japan Initiative for Global Research Network on Infectious Disease (J-GRID) established the Indonesia-Kobe University Collaborative Research Center for Emerging and Reemerging Infectious Diseases (CRC-ERID). The results of serotype and genotype, in Surabaya and Bangkalan are similar with previous result in Indonesia, but especially in Bogor similar with Japan 2014. This study showed the importance of continuous virus surveillance in dengue endemic areas, in order to understand the dynamic of dengue infection disease in Indonesia.

Genetic Variant of SARS-CoV-2 Isolates in Indonesia: Spike Glycoprotein Gene

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), a novel coronavirus and the primary causative agent of coronavirus disease 2019 (COVID-19), first occurred in China and rapidly spread worldwide. The government of the Republic of Indonesia confirmed its first two cases of COVID-19 in March 2020. COVID-19 is a serious illness with no efficacious antiviral medication or approved vaccine currently available. Therefore, there is a need to investigate the genome of SARS-CoV-2. In this study, we characterized SARS-CoV-2 spike glycoprotein genes from Indonesia to investigate their genetic composition and variability. Overall, ten SARS-CoV-2 spike glycoprotein gene sequences retrieved from GenBank (National Center for Biotechnology Information, USA) and the GISAID EpiCoV database (Germany) were compared. We analyzed nucleotide variants and amino acid changes using Molecular Evolutionary Genetics Analysis (MEGA) X and analyzed gene similarity using the LALIGN web server. Interestingly, we revealed several specific mutation sites, however, there were no significant changes in the genetic composition of SARS-CoV-2 spike glycoprotein genes, when compared to the Wuhan-Hu-1 isolate from China. However, this is a preliminary study and we recommend that molecular epidemiology and surveillance programs against COVID-19 in Indonesia be improved.

RNA ISOLATION OF DENGUE VIRUS TYPE 1 WITH DIFFERENT PRECIPITATION SOLVENTS: DIMETHYL SULFOXIDE, ACETONE, AND ETHANOL 70%

Dengue Hemorrhagic Fever (DHF) is caused by dengue viruses that belong to Flaviviridae. The disease is known to be caused by 4 types of dengue viruses, namely DENV-1, DENV-2, DENV-3, and DENV-4 associated with antigenic. Dengue virus is a virus RNA that causes illness with clinical manifestations of Dengue Fever, Dengue Hemorrhagic Fever and Dengue Shock Syndrome. The aim of research was to determine the effectiveness of dimethyl sulfoxide, acetone, and ethanol 70% as precipitation solvent in the process of RNA isolation. The method used was Reverse Transcription - Polymerase Chain Reaction (RT-PCR) and Polymerase Chain Reaction (PCR) with specific primers for dengue virus type 1 (DENV-1). RNA isolation can be done easily using an RNA Isolation Kit. Use of RNA Isolation Kit results in a purer RNA isolate from contaminants and from RNA degradation. In generally the isolation is using cold ethanol / alcohol with concentration 90-95%. Ethanol / Alcohol does not dissolve RNA and light density of alcohol lighter than water makes RNA rise and hover on the surface. In RNA isolation solvent precipitation that used are acetone, ethanol 70%, and DMSO. In qualitative RNA measurements using agarose gel electrophoresis and was examined under the UV light-illuminator and quantitative RNA measurements using Nanodrop spectrophotometry with absorbance ratio at 260/280 and 260/230 showed a good result indicated by the appearance of the band on electrophoresis results in PCR. While the measurement quantitatively is showed that there was still protein contamination but the results are quite good because it does not much different from the ratio set in the reference. Acetone, ethanol 70%, and DMSO can be used as a substitute of 96% ethanol in the process of RNA isolation in DENV-1 virus and can also be applied to other dengue virus because the structure of the 4th antigen serotype is very similar one with the other and no effect.