Diagnostic Accuracy of Various Immunochromatographic Tests for NS1 Antigen and IgM Antibodies Detection in Acute Dengue Virus Infection

Clinical spectrum and risk factors of severe dengue infection: findings from the 2023 dengue outbreak in Bangladesh

BACKGROUND

Since the first detection of dengue in 2000, Bangladesh has been facing an increasing number of dengue patients and related deaths every year. This situation warrants the importance of quickly identifying severe dengue patients to expedite necessary medical interventions which could potentially reduce the adverse consequences. The aim of this study was to identify clinical features and laboratory parameters of the severe dengue patients in the 2023 dengue outbreak in Bangladesh.

METHODS

This hospital based cross-sectional study included the demographic, clinical and laboratory data of 1313 Dengue patients from several secondary and tertiary hospitals across Bangladesh from August 2023 to December 2023. According to the 2009 WHO classification, dengue cases were classified into severe dengue and non-severe dengue (with and without warning signs). Chi-square test, Fischer's exact test and multiple logistic regression analyses were conducted to identify potential risk factors associated with severe dengue cases.

RESULTS

Of the 1313 patients included in this study, nearly 20% had severe dengue, 36.71% of them were from the 16-25 year age bracket and nearly two-thirds were male. Fever (99.54%) was the most common clinical symptom followed by anorexia (69.54%) and severe headache (66.03%); whereas most common warning signs were severe lethargy (43.64%), persistent vomiting (27.57%), and severe abdominal pain and tenderness (20.03%) across all patients. Gastrointestinal symptoms such as nausea, vomiting, and diarrhea are significantly more common in severe dengue cases compared to non-severe ones. Among the laboratory parameters, decrease of platelet level and increased ALT level was more prominent in severe patients. Multiple logistic regression analysis found that severe abdominal pain, severe lethargy, respiratory distress, altered mental status, decreased urine output, pleural effusion and ascites were positively associated with the development of severe dengue.

CONCLUSION

This study presents warning signs, clinical symptoms and trends of laboratory parameters associated with severe cases of dengue in Bangladesh that can be used in improving patient management in the future.

Dengue among suspected patients with dengue admitted at a tertiary level hospital in Mymensingh region of Bangladesh: A hospital-based epidemiological study

BACKGROUND

Dengue, a mosquito-borne disease predominantly found in tropical and subtropical countries like Bangladesh. The Aedes species particularly Aedes aegypti carry and transmit the dengue virus thus causing dengue fever irrespective of age, gender, race or religion. Limited studies on dengue in low endemic zone of Bangladesh are available. This study attempted to investigate factors influencing dengue among suspected patients with dengue in a tertiary level hospital at Mymensingh region of Bangladesh.

METHODS

A hospital-based cross-sectional study was conducted among 381 suspected patients with dengue admitted to Mymensingh Medical College Hospital, Mymensingh, Bangladesh from June 2023 to December 2023. A face to face interview was performed and there were no ignored cases in this study. Dengue infection was confirmed by a positive result of NS1 dengue antigen test if the blood sample taken within 7 days of the onset of fever, and IgM antibody test if the blood sample taken after 7th day of symptoms. The chi-square test and binary logistic regression model were used to determine the influencing factors of dengue using SPSS software (IBM version 25).

RESULTS

Most of the suspected patients came from urban environment (64.3%). The prevalence of dengue among suspected patients with dengue admitted at hospital was 74.3%, among them 45.9% and 28.3% were confirmed as dengue fever by NS1 antigen and IgM test respectively. Logistic regression model demonstrated that female had more likely to get dengue than male [aOR = 2.08, CI:1.09-3.93; p < 0.05]. Similarly, patients came from urban environment [aOR = 5.99, CI:3.09-11.64; p < 0.01], travel history to Dhaka in last two weeks preceding the survey [aOR = 11.21, CI:5.30-23.72; p < 0.01], participants did not use mosquito net during sleeping at day time [aOR = 2.74, CI:1.41-5.55; p < 0.01] and presence of water containers around the house [aOR = 12.00, CI: 5.69-25.29; p < 0.01] had higher chance to get dengue compared to their counterparts.

CONCLUSION

More than 25% suspected patients were not identified as dengue patients. Some factors were identified as risk for dengue. A safe working and living environment, self and community awareness and planned urbanization can help to prevent breeding of mosquito larvae that transmit dengue virus thus causing dengue.

Clinical Performance of MAGLUMI Diagnostic Tests for the Automated Detection of Dengue Virus

AIMS

The screening and diagnosis of dengue virus infection play a crucial role in controlling the epidemic of dengue fever, highlighting the urgent need for a highly sensitive, simple, and rapid laboratory testing method. This study aims to assess the clinical performance of MAGLUMI Denv NS1 in detecting dengue virus NS1 antigen.

METHODS

A retrospective study was conducted to assess the sensitivity and specificity of MAGLUMI Denv NS1 using residual samples. Dengue-confirmed and excluded samples, validated by qPCR, were subjected to testing with MAGLUMI Denv NS1 in accordance with the manufacturer's instructions. The linear range, endogenous interference, and cross-reactivity of MAGLUMI Denv NS1 were verified, and a consistency analysis with commercial comparator products was carried out.

RESULTS

The diagnostic specificity of MAGLUMI Denv NS1 is 98.41% (62/63), and the sensitivity is 98.32% (117/119). It effectively detects various serotypes of dengue virus, with no observed endogenous interference or cross-reactivity. Additionally, the consistency of NS1, IgM, and IgG tests on the MAGLUMI platform compared to commercial comparator reagents reaches 85.71%, 99.25%, and 98.97%, respectively.

CONCLUSIONS

The MAGLUMI Denv NS1 represents a highly sensitive laboratory testing method capable of enhancing the diagnostic accuracy and efficiency of dengue virus infection detection.

Evaluating a rapid molecular assay in a mobile laboratory for improved diagnosis of dengue in Bangladesh

OBJECTIVES

Dengue emerged as a significant health threat in endemic regions in recent years. However, inconsistent diagnostic accuracy in sequential dengue infections necessitate improved testing methods to ensure effective management of dengue cases. Here, we evaluated a portable, rapid, and sensitive molecular assay-reverse transcriptase recombinase polymerase amplification assay (RT-RAA)-utilizing a mobile suitcase laboratory to detect infections in suspected dengue cases in Bangladesh.

METHODS

A total of 364 suspected patients with dengue were enrolled in the study. Dengue cases were confirmed by a positive result from any of the four tests: non-structural protein 1 (NS1) rapid diagnostic test (RDT), immunoglobulin (Ig) M RDT, quantitative reverse transcriptive-polymerase chain reaction (RT-PCR), and RT-RAA assay. IgG RDT was performed to differentiate between primary and secondary dengue infections.

RESULTS

Of 364 suspected cases, 320 were confirmed dengue cases, with 55.94% classified as primary and 44.06% as secondary infections. Laboratory results showed comparable positivity rates between RT-RAA (78.8%) and NS1 RDT (77.1%) in primary dengue, followed by quantitative RT-PCR (57.5%) and IgM RDT (12.8%). RT-RAA demonstrated superior positivity rates in secondary dengue (76.6%), surpassing RT-PCR (60.3%), NS1 RDT (27%), and IgM RDT (24.8%). Combining RT-RAA with NS1 RDT detected infections in 89.95% primary and 81.56% secondary dengue.

CONCLUSIONS

The findings suggest that complementing RT-RAA with NS1 RDT could significantly improve dengue detection rate, particularly, for secondary infections.

Utilization of novel molecular multiplex methods for the detection and, epidemiological surveillance of dengue virus serotypes and chikungunya virus in Burkina Faso, West Africa

BACKGROUND

Dengue virus (DENV) and Chikungunya virus (CHIKV) are major arboviruses that are transmitted to humans by Aedes aegypti (A. aegypti) and Aedes Albopictus (A. Albopictus) mosquitoes. In absence of specific antivirals and vaccine against these two viruses, prompt diagnosis of acute infections and robust surveillance for outbreak identification remain crucial. Therefore, rapid, robust, high-throughput, accessible, and low-cost assays are essential for endemic countries. This study evaluated our recently developed multiplex RT-PCR and RT-qPCR assays to screen for DENV1-4 and CHIKV circulation in Burkina Faso.

METHODS AND RESULTS

This study, conducted between June to August 2023, enrolled patients with suspected arbovirus infection presenting at healthcare facilities in three Burkina Faso cities (Bobo-Dioulasso, Houndé, and Ouagadougou). Serum samples were collected and screened for DENV serotypes and CHIKV using our newly multiplex RT-PCR and RT-q PCR techniques recently developed. A total of 408 patients (age median = 33, range from 3 to 84 years) participated in this study. Of these, 13.7% (56/408) had DENV infection; DENV-1 was 32.1% (18/56) and DENV-3 was 67.9% (38/56). DENV-2, DENV-4 and CHIKV were not detected.

CONCLUSIONS

This study demonstrates the effectiveness of our molecular methods for DENV detection and serotyping in Burkina Faso. The affordability of our methods makes them valuable for implementing widespread routine clinical diagnostics or arbovirus surveillance in resource-limited settings.

Systematic review and meta-analysis: assessing the accuracy of rapid immunochromatographic tests in dengue diagnosis

The objective of this systematic review is to analyze the diagnostic accuracy of rapid dengue diagnostic tests. The search was conducted in the following databases: LILACS, Medline (Pubmed), CRD, The Cochrane Library, Trip Medical Database and Google Scholar. ELISA and PCR assays were adopted as reference methods. Thirty-four articles were included in this systematic review. Receiver operating characteristic (ROC) and Forest Plot were performed to evaluate sensitivity and specificity for each parameter analyzed (NS1, IgM and IgG). The results revealed that the combined analysis of the IgM antibody with the NS1 antigen resulted in greater sensitivity than the isolated analysis of IgM. The three analytes together showed the best performance, with a combined sensitivity of 90 % (95 % CI: 89-92 %) using ELISA as a comparator. Thus, the present review provides relevant knowledge for decision-making between the available rapid diagnostic tests.

The One Health Concept

The concept of One Health has been developed as the appreciation that human health is intricately connected to those of other animals and the environment that they inhabit. In recent years, the COVID-19 pandemic and noticeable effects of climate change have encouraged national and international cooperation to apply One Health strategies to address key issues of health and welfare. The United Nations (UN) Sustainable Development Goals have established targets for health and wellbeing, clean water and sanitation, climate action, as well as sustainability in marine and terrestrial ecosystems. The One Health Quadripartite comprises the World Health Organization (WHO), the World Organization for Animal Health (WOAH-formerly OIE), the United Nations Food and Agriculture Organization (FAO) and the United Nations Environment Programme (UNEP). There are six areas of focus which are Laboratory services, Control of zoonotic diseases, Neglected tropical diseases, Antimicrobial resistance, Food safety and Environmental health. This article discusses the concept of One Health by considering examples of infectious diseases and environmental issues under each of those six headings. Biomedical Scientists, Clinical Scientists and their colleagues working in diagnostic and research laboratories have a key role to play in applying the One Health approach to key areas of healthcare in the 21st Century.

Diagnostic Performance of Dengue NS1 and Antibodies by Serum Concentration Technique

Dengue infection has been a public health problem worldwide, especially in tropical areas. A lack of sensitive diagnostic methods in the early phase of the illness is one of the challenging problems in clinical practices. We, herein, analyzed 86 sera of acute febrile patients, from both dengue and non-dengue febrile illness, to study the diagnostic performance of dengue diagnostics. When compared with detection by Polymerase Chain Reaction (PCR), dengue NS1 detection by enzyme-linked immunosorbent assay (ELISA) had the highest sensitivity of 82.4% (with 94.3% specificity), while NS1 by rapid diagnostic test (RDT) had 76.5% sensitivity. IgM detection by ELISA and RDT showed only 27.5% and 17.9% sensitivity, respectively. The combination of NS1 and IgM in RDT yielded a sensitivity of 78.4%, with 97.1% specificity. One of the essential steps in making a diagnosis from patient samples is the preparation process. At present, a variety of techniques have been used to increase the number of analytes in clinical samples. In this study, we focused on the sample concentration method. The sera were concentrated three times with the ultrafiltration method using a 10 kDa molecular weight cut-off membrane. The results showed an increase in the sensitivity of RDT-NS1 detection at 80.4%, with 100% specificity. When combining NS1 and IgM detection, the concentration method granted RDT an 82.4% sensitivity, with 100% specificity. In conclusion, serum concentration by the ultrafiltration method is a simple and applicable technique. It could increase the diagnostic performance of point-of-care dengue diagnostics.