Correlation Between Quantitative Hepatitis B Surface Antigen and Hepatitis B Virus Deoxyribonucleic Acid Levels in Hepatitis B e Antigen-Positive and Hepatitis B e AntigenNegative Chronic Hepatitis B Patients.

BACKGROUND: This study aimed to analyze the relationship between quantitative hepatitis B surface antigen and hepatitis B virus deoxyribonucleic acid in hepatitis B e antigen-positive and hepatitis B e antigen-negative chronic hepatitis B patients and to determine the best cut-off value for quantitative hepatitis B surface antigen to predict high hepatitis B virus deoxyribonucleic acid levels (≥2000 IU/mL). METHODS: Ninety-seven sera from chronic hepatitis B patients were collected in this study. Hepatitis B virus deoxyribonucleic acid levels were quantified by real-time polymerase chain reaction. Quantitative hepatitis B surface antigen and hepatitis B e antigen levels were determined by two-site sandwich chemiluminescence immunoassay. Alanine transaminase levels were measured by the International Federation of Clinical Chemistry-approved methods. RESULTS: A significant correlation between quantitative hepatitis B surface antigen and hepatitis B virus deoxyribonucleic acid levels was observed in hepatitis B e antigen-positive group (r = 0.453, P = .002), but not in hepatitis B e antigen-negative group (r = 0.117, P = .454). No significant correlation between quantitative hepatitis B surface antigen and alanine transaminase was found in the hepatitis B e antigen-positive group (r = 0.521, P = .241). However, a significant correlation was shown between quantitative hepatitis B surface antigen and alanine transaminase levels in the hepatitis B e antigen-negative group (r = 0.455, P = .001). The best cut-off value of quantitative hepatitis B surface antigen for predicting high hepatitis B virus deoxyribonucleic acid levels was 3.422 × 103 IU/mL. CONCLUSION: Correlation between quantitative hepatitis B surface antigen and hepatitis B virus deoxyribonucleic acid levels is significant in the hepatitis B e antigen-positive group. Quantitative hepatitis B surface antigen can be used to predict high hepatitis B virus deoxyribonucleic acid levels in the hepatitis B e antigen-positive group.

The Comparison of Monocyte Human Leukocyte Antigen-D-Related (mHLA-DR) Expression Levels Between Corona Virus Disease 2019 (COVID-19) Patients and Healthy Subjects.

BACKGROUND: SARS-CoV-2 can trigger a dysfunctional immune response in COVID-19 patients and lead to immunosuppression. HLA-DR molecule expressed on the surface of monocytes, known as mHLA-DR, has been widely used as a reliable marker of immunosuppression. Downregulation of mHLA-DR reflects an immunosuppressed state. This study aimed to compare the expression level of mHLA-DR between COVID-19 patients and healthy subjects concerning immune system dysregulation that can be triggered by SARS-CoV-2 and lead to immunosuppression. METHODS: This was an analytic observational study with a cross-sectional design that measured the mHLA-DR expression in EDTA blood samples from 34 COVID-19 patients and 15 healthy subjects using the BD FACSLyricTM Flow Cytometry System. The mHLA-DR examination results were expressed in AB/C (antibodies bound per cell) that were quantified using a standard curve constructed with Quantibrite phycoerythrin beads (BD Biosciences). RESULTS: Expression of mHLA-DR in COVID-19 patients (n = 34) were 21,201 [2,646-92,384] AB/C, with 40,543.5 [9,797-92,384] AB/C mild cases (n = 22), 21,201 [9,831-31,930] AB/C moderate cases (n = 6), and 7,496 [2,646-13,674] AB/C severe to critical cases (n= 6). Expression of mHLA-DR in healthy subjects (n = 15) was 43,161 [25,147-89,846] AB/C. Based on the Mann-Whitney U test, the mHLA-DR expression in COVID-19 patients significantly differed from the mHLA-DR expression in healthy subjects (p = 0.010). CONCLUSION: The level of mHLA-DR expression in COVID-19 patients was lower and significantly different from healthy subjects. Moreover, immunosuppression could be indicated by the decrease of mHLA-DR expression, which was below the reference range found in severe to critically ill COVID-19 patients.

Impact of Hemin on Interleukin-21 Levels and Plasma Cells in Transfusion-Dependent Thalassemia with Positive and Negative Allo-Autoantibody.

Introduction: Antibody formation in transfusion-dependent thalassemia is associated with chronic hemolysis and repeated transfusions. Hemolysis produces heme, which mediates B-cell differentiation into plasma cells and produces antibodies influenced by interleukin-21 (IL-21). Objective: This study aimed to compare IL-21 levels, plasma cell percentage, and red blood cell antibodies between positive and negative allo-autoantibody thalassemia before and after hemin administration. Materials and Methods: This research employed a quasi-experimental nonequivalent control group pre-test and post-test design performed from April to November 2021 at Soetomo Academic Hospital in Surabaya, Indonesia. Heparinized blood samples of 5 mL and 4 mL and EDTA blood samples of 3 mL were taken from positive (29 patients) and negative (28 patients) allo-autoantibody thalassemia participants. Hemin 20 µM was added to 5 mL of heparinized blood, incubated for 2 hours, prepared into peripheral blood mononuclear cells (PBMCs), and cultured for 3 days. The percentage of plasma cells (CD38+CD184+) of cultured and uncultured PBMCs was measured by BD FACSCalibur Flow Cytometer. IL-21 levels of plasma and supernatants were measured with Sandwich Enzyme-Linked Immunosorbent Assay by Elabscience. Red blood cell antibodies were detected by QWALYS 3 E.M. Technology. Autoantibodies were determined by the Grifols gel tube method. Results: IL-21 levels were significantly different in the positive and negative allo-autoantibody thalassemia groups after hemin administration. The percentage of plasma cells in the positive allo-autoantibody group increased significantly after the administration of hemin. The percentage of plasma cells between thalassemia groups was not significantly different before the hemin administration but increased significantly after it. Red blood cell antibodies after the administration of hemin were significantly different in the negative allo-autoantibody group but not significantly different in the positive allo-autoantibody group. Conclusion: Hemin administration affected IL-21 levels, plasma cell percentage, and antibody formation in positive and negative allo-auto antibody thalassemia.

Effect of MTHFR A1298C Gene Polymorphism on Acute Coronary Syndrome.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Acute coronary syndrome is a manifestation of CVD. In Indonesia, limited studies have been conducted on genetics as a potential risk factor for acute coronary syndrome (ACS). Consequently, this study aimed to examine the effect of the methylenetetrahydrofolate reductase (MTHFR) A1298C gene polymorphism on the incidence of ACS. METHOD: The study employed a case-control design. Outpatients from the cardiology and internal medicine clinics at the University of Airlangga (UNAIR) Hospital in Surabaya, Indonesia, constituted the study population. The case group comprised 60 patients with a history of ACS, while the control group consisted of 30 patients without a history of cardiovascular complaints. MTHFR A12980C gene polymorphism examination was performed using the polymerase chain reaction-restriction fragment length polymorphism (PCR RFLP) method at the Tropical Disease Center UNAIR Laboratory. RESULTS: Among the ACS group, 29 (48.1%), 13 (21.7%), and 18 (30%) of the individuals had AA, AC, and CC genotype patterns, respectively. In the control group, 16 individuals had AA (53.3%), 6 AC (20%), and 8 CC (26.7%). The C allele variant was identified in 41% of the ACS group and 37% of the control group. The odds ratio (OR) for the incidence of ACS was 1.195 (95% confidence interval [CI]; 0.381-3.752), 1.241 (95% CI; 0.481-3.486), and 1.222 (95% CI; 0.381-3.752). Chi-square analysis revealed no association between MTHFR A1298C gene polymorphism and the incidence of ACS (P > 0.05). CONCLUSIONS: MTHFR A1298C gene polymorphism did not significantly affect ACS incidence.

Non-structural protein 1 and hematology parameters as predictors of dengue virus infection severity in Indonesia.

Dengue virus infection (DVI) remains a significant health challenge, and diagnosis must still be considered. Non-structural protein 1 (NS1) is a potential marker of the dengue virus that can help diagnose DVI. The study aimed to assess the role of NS1 as a predictor of the severity of DVI. We utilized Dengue PCR-confirmed samples and employed semi-quantitative NS1Ag ELISA for NS1 examination, adhering to the World Health Organization South-East Asia Region (WHO-SEARO) 2011 criteria for DVI. We included DVI patients from Indonesia aged 1-65 years. Secondary infections had more severe clinical conditions than primary infections. Leukocyte and platelet levels had a more significant effect on NS1 positivity (6.19 (1.9-30.2); p<0.001; 190 (11-417); p=0.015; respectively). Multivariate analysis revealed leukocytes as a more significant predictor of NS1 values than platelets, with an odds ratio of 5.38 contributing to 30.5% of the NS1 value variation. The NS1 value could distinguish undifferentiated fever and dengue fever in the children group with a sensitivity of 76.0% and specificity of 87.5% (p=0.015). The number of NS1(-) in the severe dengue hemorrhagic fever (DHF) group was higher than NS1(+). DENV-4 type and primary infection were dominant in this study, although they did not significantly differ from the NS1 value. NS1 value can be used as a predictor to determine the severity of DVI in children but not in the adult group. The levels of leukocytes and platelets influenced the NS1 value.

The role of mediator suppressor of cytokine signaling (SOCS), toll-like receptor 3 (TLR-3) and nuclear factor kappa B (NFκB) on cytokine production during dengue virus infection.

Inability to understand the pathogenesis of severe dengue, in particular the control mechanism of immune responses, has led to high mortality rate for patients with dengue shock syndrome (DSS). The aim of this study was to determine the control mechanism of cytokine production by mediator suppressor of cytokine signaling (SOCS), toll-like receptor 3 (TLR-3) and nuclear factor kappa B (NFκB) during DENV infection. Peripheral blood mononuclear blood cells (PBMC), isolated from healthy individuals, were infected with dengue virus (DENV)-2 strain SJN-006 Cosmopolitan genotype (isolated from Bali, Indonesia). The relative gene expression of SOCS-3, TLR-3, NFκB, and the cytokine genes (interleukin (IL)-6, IL-8, interferon inducible protein 10 (IP-10), and macrophage inflammatory protein-1 beta (MIP-1ß)) were measured using qRT-PCR at 6, 12 and 24 hours post infection (hpi). Student t-test and Mann-Whitney test were used to compare the gene expressions while causal correlations were analyzed using regression test and path analyses. DENV-2 infection increased the gene expression of SOCS-3, TLR-3, and NFκB after 12 and 24 hpi. The expression of IL-6, IL-8, IP-10, and MIP-1ß genes was increased and peaked at different times post-infection. NFκB and SOCS-3 genes likely have role in the upregulation of IL-8 and IL-6 gene expression, respectively. MIP-1ß gene expression was significantly induced by both NFκB and SOCS-3. In conclusion, our study suggested that SOCS-3, TLR-3, and NFκB are important in regulating the production of IL-6, IL-8, IP-10, MIP-1ß during early phase of DENV-2 infection. This enriches our understanding on pathogenesis pathway of DENV-associated cytokine storm.

Risk Assessment on the Release of Wolbachia-Infected Aedes aegypti in Yogyakarta, Indonesia.

Wolbachia-infected Aedes aegypti is the latest technology that was developed to eliminate dengue fever. The Ministry of Research and Technology of the Republic of Indonesia (Kemenristekdikti) established an expert group to identify future potential risks that may occur over a period of 30 years associated with the release of Wolbachia-infected Ae. aegypti. The risk assessment consisted of identifying different hazards that may have impacts on humans and the environment. From the consensus among the experts, there were 56 hazards identified and categorized into 4 components, namely, ecological matters, efficacy in mosquito management, economic and sociocultural issues, and public health standards. There were 19 hazards in the ecological group. The overall likelihood in the ecology of the mosquito is very low (0.05), with moderate consequence (0.74), which resulted in negligible risk. For the efficacy in mosquito management group, there were 12 hazards that resulted in very low likelihood (0.11) with high consequence (0.85). The overall risk for mosquito management efficacy was very low (0.09). There were 14 hazards identified in the public health standard with very low likelihood (0.07), moderate consequence (0.50) and negligible risk (0.04). Lastly, 13 hazards were identified in the economic and sociocultural group with low likelihood (0.01) but of moderate consequence (0.5), which resulted in a very low risk (0.09). The risk severity level of the four components leading to the endpoint risk of "cause more harm" due to releasing Wolbachia-infected Ae. aegypti is negligible (0.01).

Relationship between Bax and Bcl-2 Protein Expression and Outcome of Induction Phase Chemotherapy in Pediatric Acute Lymphoblastic Leukemia.

BACKGROUND: Overexpression of the antiapoptotic protein Bcl-2 causes apoptosis to stop and conversely the increased expression of the proapoptotic protein Bax makes lymphoblasts easy to destroy. The Bax/Bcl-2 ratio plays a role in the balance of apoptosis, immortality, resistance, and outcome of chemotherapy. We analyzed the relationship between the Bax/BCl-2 ratio and the outcome of induction phase chemotherapy in pediatric Acute Lymphoblastic Leukemia (ALL). METHODS: This research was conducted with a prospective observational study on pediatric ALL aged 1-18 years who were newly diagnosed based on bone marrow aspiration (morphology and immunophenotyping) at Dr. Soetomo General Hospital, Surabaya on October 2020 to March 2021. Expression of Bcl-2, Bax, and Bax/Bcl-2 protein ratio was measured by the flow cytometry method from lymphoblast on bone marrow aspirate samples before and after induction phase chemotherapy according to the 2018 Childhood ALL Indonesian Protocol. The outcomes evaluated were survival and remission rate (lymphoblasts in the bone marrow less than 5%). We used the Mann-Whitney U test and Wilcoxon Signed Rank test to analyze the differences between protein expression with p<0.05 for a two-tailed test. RESULTS: We included 17/26 pediatric ALL, consisting of 88% male, 94% LLA-L1, 76% B cell ALL and 24% T cell ALL. Mean expression of Bax, Bcl-2, and Bax/Bcl-2 protein ratio before chemotherapy among pediatric ALL who alive (N=11) and dead (N=6) were not significantly different (p>0.05). All children who completed the induction phase of chemotherapy went into remission. Bax and Bcl-2 expression before and after chemotherapy showed no difference (p>0.05). The Bax/Bcl-2 ratio increased from 1.74(SD 1.846) to 6.17(4.139) with p=0.021. CONCLUSION: Expression of Bax, Bcl-2, and Bax/Bcl-2 protein ratio at the beginning of diagnosis did not affect the survival of pediatric ALL after the induction phase of chemotherapy. The Bax/Bcl-2 protein ratio increased 3.5 times in pediatric ALL with remission outcomes, indicating proapoptotic dominance.

The Potential Predictive Role of Tumour Necrosis Factor-α, Interleukin-1ß, and Monocyte Chemoattractant Protein-1 for COVID-19 Patients Survival.

Background: Tumour necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and monocyte chemoattractant protein-1 (MCP-1) are early phase cytokines often encountered when the body is exposed to severe acute respiratory syndrome-associated-coronavirus-2. TNF-α, IL-1ß, and MCP-1 are pro-inflammatory cytokines critical in the defence response against systemic infection and injury. Therefore, TNF-α, IL-1ß, and MCP-1 are the most aggressive responses to viral infections in the acute phase, so they can be used to determine the survival of coronavirus disease 2019 (COVID-19) patients. Purpose: The study aimed to determine the levels of TNF-α, IL-1ß, and MCP-1 as predictors of survival for COVID-19 patients. Patients and Methods: A prospective cohort study was conducted on confirmed COVID-19 by a reverse-transcriptase-polymerase-chain-reaction (RT-PCR) in 84 adults admitted to the hospital in Indonesia. TNF-α, IL-1ß, and MCP-1 level were measured from serum subjects using the enzyme-linked immunosorbent assay. Results: The results from logistic regression modelling of the survival status of COVID-19 patients based on TNF-α, IL-1ß, and MCP-1 levels were significant (p-value=0.024). The predictors of all cytokines had P Wald <0.05, so the three cytokines could be used simultaneously to predict the survival status of COVID-19 patients. MCP-1 has the most dominant risk relative value (2.76; 95% CI; 2.53-4.68) compared to TNF-α and IL-1ß in predicting patient survival. Conclusion: TNF-α, IL-1ß, and MCP-1 as markers of acute systemic inflammatory cytokines can be measured at the beginning of hospitalisation of COVID-19 patients for early diagnosis of disease severity so that healthcare professionals can determine clinical guidance needs for therapeutic programs.

Characterization of SARS-CoV-2 East Java isolate, Indonesia.

Background: Incidents of SARS-CoV-2 in East Java increased steadily, and it became the second epicenter in Indonesia. The COVID-19 pandemic caused a dire multisectoral crisis all around the world. This study investigates and characterizes local isolates from East Java, Indonesia.   Methods: There were 54 patients suspected with SARS-COV-2 infection and 27 patients were COVID-19 positive. Virus isolates were obtained from COVID-19 inpatients' nasopharyngeal swabs at the Dr Soetomo Teaching Hospital, Surabaya. There were only three isolates (#6, #11, #35) with good growth characteristics. Serial blind passage and cytopathic effect observation in the Vero E6 cell line were performed for virus isolation. Confirmation of the SARS-CoV-2 infection was proven by means of reverse transcriptase-polymerase chain reactions using SARS-CoV-2 specific primers, scanning electron microscopy, and scanning transmission electron microscopy examination. Whole genome sequencing was performed using ARTIC protocol. Furthermore, SARS-CoV-2 characterization was identified through a western blot using rabbit serum immunized with inactive SARS-CoV-2 vaccine and human natural COVID-19 infection serum.   Results: Spike gene analysis of three samples (#6, #11, #35) found that the D614G mutation was detected in all isolates, although one isolate exhibited the D215Y and E484D mutation. Based on whole genome analysis, those three isolates were included in clade 20A, and two isolates were included in lineage B.1.6 with one isolate belongs to lineage B.1.4.7.   Conclusion: Based on molecular characterization and immunogenicity of SARS-CoV-2 East Java, Indonesia showed high titer and it has mutation in some regions.

Correlation of miR-150, hsa-let-7e, and miR- 146a and gene expression of IL-6, IL-8, IP-10, and MIP-1ß during dengue virus infection.

Growing evidence suggests that microRNAs (miRNAs) play a pivotal role in viral infection. The objective of this study was to assess the association between the expression of miR- 150, hsa-let-7e, and miR-146a on cytokine expression during dengue infection. Dengue virus (DENV) strain SJN-006, a serotype 2 DENV strain of the Cosmopolitan genotype, isolated in Bali, Indonesia, was used to infect peripheral blood mononuclear cells (PBMCs) isolated from healthy individuals. The relative gene expressions of miR-150, hsa-let-7e, and miR-146a as well as the gene expression of cytokines (IL-6, IL-8, IP-10, and MIP-1ß) were determined using quantitative real time - polymerase chain reaction (qRT-PCR) at 6, 12 and 24 hours post infection (hpi). Correlations between the microRNAs and cytokines were analyzed by means of causality tests. Our data suggests that miR-150 and hsa-let-7e were significantly higher in infected-PBMCs after 12 hpi compared to the uninfected-PBMCs (p<0.05). The causality tests demonstrated that miR-150 and has-let- 7e were negatively correlated with IL-8 expression, meanwhile miR-146a was the contrast. DENV infection was negatively and positively correlated with miR-150 and hsa-let-7e, respectively, after 24 hpi. In conclusion, our data demonstrates the vital role of miR-150, hsa-let-7e, and miR-146a in regulating IL-8 expression with possible different pathways.

Effectivity of zinc oxide-turmeric extract dressing in stimulating the reepithelization phase of wound healing.

BACKGROUND AND AIM: Reepithelialization can be described as the resurfacing of a wound with new epithelium in the process of healing, with the overlapping step from keratinocyte migration and proliferation to the tissue contraction. Zinc oxide-turmeric extract dressing has been proven to have anti-inflammatory properties, but its effectivity in the reepithelialization process is still unknown. This study aimed to determine the effect of a wound dressing consisting of zinc oxide and turmeric extract on wound reepithelialization by assessing the expression of cytokeratin 14 (CK14), epidermal growth factor receptor (EGFR), and epithelial cadherin (E-cadherin). MATERIALS AND METHODS: A total of 40 Wistar rats were randomized into four control and four treatment groups (n=5 per group). On day 1, a square-shaped full-thickness skin excision measuring 6×6 mm in size was created in the dorsal thoracic area of the rats, and the wounds were either dressed with a combination of zinc oxide and turmeric extract in the treatment groups or left undressed in the control groups. Then, the rats were sequentially sacrificed on days 3, 5, 7, and 14 to obtain subepithelial excision samples, which were subsequently subjected to immunohistochemistry analysis for the expression of CK14, EGFR, and E-cadherin to ascertain wound reepithelization. The data were tabulated and analyzed using a one-way analysis of variance and least significant difference test. RESULTS: The highest expression levels of CK14, EGFR, and E-cadherin were observed on days 7 and 14 in the treatment and control groups, respectively. While the expression levels of these markers on day 7 were found to be significantly higher in the treatment than the control groups, no significant difference in the expression levels on day 14 was detected between the control and treatment groups (p<0.05). CONCLUSION: A wound dressing consisting of zinc oxide and turmeric extract can help accelerate reepithelization in the wound healing process.

Dengue Virus Serotype 4 Is Responsible for the Outbreak of Dengue in East Java City of Jember, Indonesia.

Outbreaks of dengue virus (DENV) in Indonesia have been mainly caused by the DENV serotype-1; -2; or -3. The DENV-4 was the least-reported serotype in Indonesia during the last five decades. We recently conducted a molecular epidemiology study of dengue in the Jember regency, East Java province, Indonesia. Dengue is endemic in the region and outbreaks occur annually. We investigated the clinical characteristics and etiology of dengue-like febrile illness in this regency to understand the disease dynamics. A total of 191 patients with clinical symptoms similar to dengue were recruited during an 11-month study in 2019-2020. Children accounted for the majority of cases and dengue burden was estimated in 41.4% of the cases based on NS1 antigen, viral RNA, and IgG/IgM antibody detection with the majority (73.4%) being primary infections. Secondary infection was significantly associated with a higher risk of severe dengue manifestation. All four DENV serotypes were detected in Jember. Strikingly, we observed the predominance of DENV-4, followed by DENV-3, DENV-1, and DENV-2. Genotype determination using Envelope gene sequence revealed the classification into Genotype I, Cosmopolitan Genotype, Genotype I, and Genotype II for DENV-1, -2, -3, and -4, respectively. The predominance of DENV-4 in Jember may be associated with a new wave of DENV infections and spread in a non-immune population lacking a herd-immunity to this particular serotype.

Emergence of Melioidosis in Indonesia and Today's Challenges.

A recent modeling study estimated that there could be as many as 20,000 human melioidosis cases per year in Indonesia, with around 10,000 potential deaths annually. Nonetheless, the true burden of melioidosis in Indonesia is still unknown. The Indonesia Melioidosis Network was formed during the first melioidosis workshop in 2017. Here, we reviewed 101 melioidosis cases (99 human and two animal cases) previously reported and described an additional 45 human melioidosis cases. All 146 culture-confirmed cases were found in Sumatra (n = 15), Java (n = 104), Kalimantan (n = 15), Sulawesi (n = 11) and Nusa Tenggara (n = 1). Misidentification of Burkholderia pseudomallei was not uncommon, and most cases were only recently identified. We also evaluated clinical manifestations and outcome of recent culture-confirmed cases between 2012 and 2017 (n = 42). Overall, 15 (36%) cases were children (age <15 years) and 27 (64%) were adults (age ≥15 years). The overall mortality was 43% (18/42). We conducted a survey and found that 57% (327/548) of healthcare workers had never heard of melioidosis. In conclusion, melioidosis is endemic throughout Indonesia and associated with high mortality. We propose that top priorities are increasing awareness of melioidosis amongst all healthcare workers, increasing the use of bacterial culture, and ensuring accurate identification of B. pseudomalleiand diagnosis of melioidosis.

Clinical and virological characteristics of dengue in Surabaya, Indonesia.

Dengue disease is still a major health problem in Indonesia. Surabaya, the second largest city in the country, is endemic for dengue. We report here on dengue disease in Surabaya, investigating the clinical manifestations, the distribution of dengue virus (DENV) serotypes, and the relationships between clinical manifestations and the genetic characteristics of DENV. A total of 148 patients suspected of having dengue were recruited during February-August 2012. One hundred one (68%) of them were children, and 47 (32%) were adults. Dengue fever (DF) and Dengue hemorrhagic fever (DHF) were equally manifested in all of the patients. We performed DENV serotyping on all of the samples using real-time RT-PCR. Of 148, 79 (53%) samples were detected as DENV positive, with DENV-1 as the predominant serotype (73%), followed by DENV-2 (8%), DENV-4 (8%), and DENV-3 (6%), while 5% were mixed infections. Based on the Envelope gene sequences, we performed phylogenetic analyses of 24 isolates to genotype the DENV circulating in Surabaya in 2012, and the analysis revealed that DENV-1 consisted of Genotypes I and IV, DENV-2 was of the Cosmopolitan genotype, the DENV-3 viruses were of Genotype I, and DENV-4 was detected as Genotype II. We correlated the infecting DENV serotypes with clinical manifestations and laboratory parameters; however, no significant correlations were found. Amino acid analysis of Envelope protein did not find any unique mutations related to disease severity.

Performance of Simplexa dengue molecular assay compared to conventional and SYBR green RT-PCR for detection of dengue infection in Indonesia.

Diagnostic tests based on detection of dengue virus (DENV) genome are available with varying sensitivities and specificities. The Simplexa Dengue assay (Focus Diagnostics) is a newly developed real-time RT-PCR method designed to detect and serotype DENV simultaneously. To assess the performance of the Simplexa Dengue assay, we performed comparison with conventional RT-PCR and SYBR Green real-time RT-PCR on patients sera isolated from eight cities across Indonesia, a dengue endemic country. A total of 184 sera that were confirmed using NS1 and/or IgM and IgG ELISA were examined. Using conventional and SYBR Green real-time RT-PCR, we detected DENV in 53 (28.8%) and 81 (44.0%) out of 184 sera, respectively. When the Simplexa Dengue assay was employed, the detection rate was increased to 76.6% (141 out of 184 samples). When tested in 40 sera that were confirmed by virus isolation as the gold standard, the conventional RT-PCR yielded 95% sensitivity while the sensitivity of SYBR Green real-time RT-PCR and Simplexa Dengue assay reached 97.5% and 100%, respectively. The specificities of all methods were 100% when tested in 43 non-dengue illness and 20 healthy human samples. Altogether, our data showed the higher detection rate of Simplexa Dengue compared to conventional and SYBR Green real-time RT-PCR in field/surveillance setting. In conclusion, Simplexa Dengue offers rapid and accurate detection and typing of dengue infection and is suitable for both routine diagnostic and surveillance.

Performance of commercial dengue NS1 ELISA and molecular analysis of NS1 gene of dengue viruses obtained during surveillance in Indonesia.

BACKGROUND: Early diagnosis of dengue infection is crucial for better management of the disease. Diagnostic tests based on the detection of dengue virus (DENV) Non Structural Protein 1 (NS1) antigen are commercially available with different sensitivities and specificities observed in various settings. Dengue is endemic in Indonesia and clinicians are increasingly using the NS1 detection for dengue confirmation. This study described the performance of Panbio Dengue Early NS1 and IgM Capture ELISA assays for dengue detection during our surveillance in eight cities in Indonesia as well as the genetic diversity of DENV NS1 genes and its relationship with the NS1 detection. METHODS: The NS1 and IgM/IgG ELISA assays were used for screening and confirmation of dengue infection during surveillance in 2010-2012. Collected serum samples (n = 440) were subjected to RT-PCR and virus isolation, in which 188 samples were confirmed for dengue infection. The positivity of the ELISA assays were correlated with the RT-PCR results to obtain the sensitivity of the assays. The NS1 genes of 48 Indonesian virus isolates were sequenced and their genetic characteristics were studied. RESULTS: Using molecular data as gold standard, the sensitivity of NS1 ELISA assay for samples from Indonesia was 56.4% while IgM ELISA was 73.7%. When both NS1 and IgM results were combined, the sensitivity increased to 89.4%. The NS1 sensitivity varied when correlated with city/geographical origins and DENV serotype, in which the lowest sensitivity was observed for DENV-4 (19.0%). NS1 sensitivity was higher in primary (67.6%) compared to secondary infection (48.2%). The specificity of NS1 assay for non-dengue samples were 100%. The NS1 gene sequence analysis of 48 isolates revealed the presence of polymorphisms of the NS1 genes which apparently did not influence the NS1 sensitivity. CONCLUSIONS: We observed a relatively low sensitivity of NS1 ELISA for dengue detection on RT-PCR-positive dengue samples. The detection rate increased significantly when NS1 data was combined with IgM. In our study, the low sensitivity of NS1 antigen detection did not relate to NS1 genetic diversity. Rather, the performance of the NS1 antigen test was affected by the infection status of patients and geographical origin of samples.