Dengue Antibodies Research Articles

SEROPREVALENCE OF DENGUE IN A TERTIARY CARE HOSPITAL: CROSS SECTIONAL STUDY

Background: Dengue is endemic and an important emerging public health problem in India. Dengue illness is major concern causing increased morbidity and mortality. Disease burden is highly variable between different places within a country. This study was conducted to determine the age wise seroprevalence of dengue and seasonal variation of dengue infection in tertiary care hospital in Mumbai. Materials And Methods: The present cross sectional study was conducted from January 2021 to March 2022 for a period of 15 months. Total 1550 serum samples were collected from suspected dengue cases. All the samples were subjected to ELISA for detection of dengue NS1 antigen and IgM antibody. Results: Out of 1550 suspected dengue patients 187 (12.06%) were seropositive for NS1antigen or IgM antibody or both NS1 antigen & IgM antibody. Of 187 seropositive dengue cases 121 (64.71%) were male and 66 (35.29%) were female. The maximum dengue cases (31.55%) were from 31-40 years age group, followed by 21-30 (23.52%) years. Most dengue positive cases were seen in monsoon period. The monsoon peak was observed in September (22.00%) followed by August (17.11%). However, in May (dry season) few cases were reported. Conclusion: Dengue illness is a major public health concern. With early diagnosis and treatment, morbidity and mortality can be reduced. Knowledge of prior infection is also very important if vaccination strategy by WHO is implemented in future. Maximum cases were observed in monsoon period but dengue cases were seen throughout the year. Hence continuous surveillance of cases is required for early diagnosis and treatment, to know the prevalence throughout the year, for vector control measures & administration of dengue vaccine as per WHO strategy if implemented in future in our country

Development of a novel diagnostic kit candidate to detect dengue antibody, using IgY and protein a positive Staphylococcus aureus

Early diagnosis of dengue hemorrhagic fever (DHF) is very important in determining further management. Diagnostic kits are intended as relatively faster, easier, and cheaper diagnostic tools. The objectives of this experimental laboratory study was to prepare a diagnostic kit candidate to detect dengue antibody in human serum using co -agglutination methods by utilizing protein A positive Staphylococcus aureus as a carrier to bind Fc immunoglobulin fractions without altering its ability to bind antigen. To enhance the sensitivity and specificity of the diagnostic kit, chicken IgY was used as one of the components. Rabbit immunoglobulin chicken anti-IgY was used as an intermediary connection between protein A positive and Staphylococcus aureus with chicken IgY. Solution A contains Staphylococcus aureus Cowan I and rabbit immunoglobulin chicken anti-IgY serum while Solution B contains anti-dengue chicken serum and dengue antigen. The laboratory experiments produced a formula of A: B = 1~3: 1~3 (v/v), which was then tested to human serum and compared with IgM and IgG ELISA tests as the gold standard. Data on the results of the test were statistically analyzed using chi - square test. Of the 65 qualified samples used, 47.69% resulted in true positive and 41.54% resulted in true negative. Meanwhile, the remaining samples demonstrated false negative (6.15%), positive predictive value (91.2%) and negative predictive value (87.1%). The sensitivity and specificity were 89% and 90%, respectively, with no significant diffe rences (p>0.05). Therefore, co-agglutination method using S. aureus with protein A positive as a carrier can be proposed as a diagnostic kit candidate to detect human serum dengue antibody to screen dengue hemorrhagic fever cases.

Central nervous system manifestations of dengue infection: data from a tertiary care Centre in South India.

Denguefever is the second most common mosquito-borne disease affecting human beings and neurological manifestations (NMs) of this arboviral infection are increasingly being reported. In this retrospective study, conducted in a tertiary care centre in south India, we sought to describe the spectrum of NMs of dengue fever. The records of all patients admitted in the Department of Internal Medicine over 8 years, with a diagnosis of dengue-based on clinical symptoms and the detection of dengue IgM antibodies or detection of NS1 antigen or nucleic acid by reverse transcriptase-polymerase chain reaction (RT-PCR); with Glasgow coma score (GCS) ≤14, neck stiffness, focal neurological signs, seizures, or visual disturbances-were explored. Of 1121 patients admitted with dengue fever, 341 (30%) had severe dengue and 23 (2%) had NMs. Encephalopathy was seen in 9 patients (39%), encephalitis in 6 (27%), cerebellitis in 4 (17%), acute disseminated encephalomyelitis (ADEM) in 2 (9%), ischaemic stroke in 1 (4%) patient, and neuro-ophthalmological manifestations in 1 (4%) patient. The median duration of hospital stay was 7 days. Nine (39% of) patients required intensive care unit (ICU) admission and 5 (22%) had fatal outcomes. There was no association between thrombocytopenia, metabolic acidosis, transaminitis, hyponatremia, the type of dengue infection, and the various NMs described. The NMs of dengue infection are varied, and a high index of suspicion is needed to identify them in patients who present with lethargy or altered sensorium on the background of an acute febrile illness suggestive of dengue.

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.

The Clinical and Laboratory Profiles of Immunocompetent Patients With Short-Duration Fever With Neutropenia in a Tertiary Care Hospital in Pune, India.

Background Management of a febrile patient is based on understanding the pathophysiology of an abnormal temperature and temperature regulation, impacts of fever, and its treatment. In the current study, we aimed to characterize and compare the epidemiological, etiologic, microbiological, serological, clinical, and outcome traits of febrile patientswith acute neutropenia admitted to a tertiary care center in Western Maharashtra. Methods Adult patientswith a history of fever of less than two weeks' duration and without any immunosuppressive state were screened with predefined inclusion and exclusion criteria. General anddemographic information (age andgender), and clinical examinations (type and duration of fever) were recorded. Biochemical, hematologic(total and differential cell counts), and immunologicmeasurements (rapid malaria, dengue, Leptospira, and viral hepatitis antigen antibodies) were performed. Data were analyzed using an appropriate statistical package. Results A total of 403 (214 males) young adults (aged: 29±11 years) with clinical presentation of fever were studied. The majority (n=361, 89.6%) had low-grade continuous fever with an average duration of 3±1 (mean±standard deviation (SD)) days. Headache and myalgia were the common symptoms present, and patients had an average hospital stay of 4±1 days. Dengue (55%) was the most common cause of febrile neutropenia, and all patients recovered well without antibiotics and granulocyte colony-stimulating factor. The mean C-reactive protein (CRP) level was 61.4±4.4 mg/L. CRP and procalcitonin (PCT) were directly correlated with the degree of neutropenia and inverselycorrelated with total leucocyte count (TLC). Conclusions It was highlighted from this study that antibiotics are not necessary for viral infections that have been diagnosed to stop the development of secondary bacterial infections. A clinician should be aware of "when not to use antibiotics,"or the world will soon have to deal with superbugs.

Seropositivity of dengue cases at a tertiary care centre in Chhindwara, Madhya Pradesh: A three year trend

BackgroundDuring the recent decades, dengue virus infection has been emerged as a major public health problem. Dengue is one of the important mosquito borne infections causing high mortality and morbidity of humans. Methods: This study was carried out from October 2018 to December 2020. A total of 354 serum samples of clinically suspected dengue patients were tested for immunoglobulin M (IgM) anti-dengue antibodies by dengue monoclonal antibody capture enzyme-linked immunosorbent assay (NIV DEN IgM Capture MAC ELISA). Seasonal variations, age and sex wise incidences were also determined. ResultsTotal of 354 serum samples were processed from October 2018 to December 2020. Each year males were mostly infected with Dengue 08, 10, and 03 in 2018, 2019, and 2020, respectively. Age group 11–20 was found to be mostly infected by Dengue in case of both male and female. The prevalence of Dengue in each year was from July to November might be due to the rainy season. Clinical characteristics of patients such as fever, headache, abdominal pain and nausea/vomiting, retro-orbital pain, epistaxis, petechiae, altered sensorium, positive tourniquet test were reported. ConclusionsContinuous dengue virus surveillance is required for monitoring of dengue virus so that early detection can be carried out. Effective vector control measures should be implemented for early detection of impending outbreak and to initiate timely control measures.

Dengue Burden and Circulation of Dengue-2 Serotype Among Children Along With Clinical Profiling in Uttarakhand, India: A Cross-Sectional Study From 2018 to 2020.

The multiple serotypes of the dengue virus (DENV) are always a major public concern for dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS). This study aimed to analyse the demographic characteristics and circulating serotypes of dengue among the paediatric age group. One hundred forty-one clinically suspected children were enrolled in the study from 2018 to 2020 in a tertiary care hospital in Uttarakhand, India. Central tendency, frequency, and One-Way ANOVA were measured for continuous and categorical data. The Shapiro-Wilks test was used to calculate the normality assumption. Dengue NS1 Ag, IgM, and IgG antibodies ELISA were performed, and NS1-positive samples were further tested for molecular studies. From one hundred forty-one suspected cases, 100 (70.92%) came positive for dengue NS1 antigen, 18 (12.76%), and three (2.12%) came positive for IgM and IgG antibodies respectively. Rest 20 (14.18%) samples came negative for dengue. Fever with chills (97.5%), headache (89%), and arthralgia (82%) were the most common clinical features. Molecular studies showed the dengue serotype-2 (DEN-2) was found in most cases, followed by the dengue-3 serotype (DEN-3). This is the preliminary study as the authors' best knowledge which demonstrate the burden of dengue in children with prevalent serotypes for consecutive three yearsin Uttarakhand. This study identifies that the serotype-2 (DEN-2) of the dengue virus was the primary cause of infection in children at the tertiary care hospital in northern India. These results will help further to understand the nature of the disease so that improved patient care management will imply. Further molecular studies on large sample sizes during the endemic would be helpful to gain knowledge of the actual load of the disease and the genetic characteristics of the virus.

Potential Protective Effect of Dengue NS1 Human Monoclonal Antibodies against Dengue and Zika Virus Infections.

Due to the lack of an effective therapeutic treatment to flavivirus, dengue virus (DENV) nonstructural protein 1 (NS1) has been considered to develop a vaccine owing to its lack of a role in antibody-dependent enhancement (ADE). However, both NS1 and its antibody have shown cross-reactivity to host molecules and have stimulated anti-DENV NS1 antibody-mediated endothelial damage and platelet dysfunction. To overcome the pathogenic events and reactogenicity, human monoclonal antibodies (HuMAbs) against DENV NS1 were generated from DENV-infected patients. Herein, the four DENV NS1-specific HuMAbs revealed the therapeutic effects in viral neutralization, reduction of viral replication, and enhancement of cell cytolysis of DENV and zika virus (ZIKV) via complement pathway. Furthermore, we demonstrate that DENV and ZIKV NS1 trigger endothelial dysfunction, leading to vascular permeability in vitro. Nevertheless, the pathogenic effects from NS1 were impeded by 2 HuMAbs (D25-4D4C3 and D25-2B11E7) and also protected the massive cytokines stimulation (interleukin [IL-]-1b, IL-1ra, IL-2, IL-4, IL-5, IL-6, IL-8, IL-9, IL-13, IL-17, eotaxin, granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, Inducible protein-10, monocyte chemoattractant protein-1, macrophage inflammatory protein [MIP]-1 α, MIP-1β, tumor necrosis factor-α, platelet-derived growth factor, and RANTES). Collectively, our findings suggest that the novel protective NS1 monoclonal antibodies generated from humans has multiple therapeutic benefits against DENV and ZIKV infections.

Serological Evidence of Zika virus Circulation with Dengue and Chikungunya Infections in Sri Lanka from 2017.

Arbovirus diseases remain a public health threat in Sri Lanka. Dengue is endemic and two outbreaks of chikungunya infections have been reported. There is limited data on Zika virus (ZIKV) infections in Sri Lanka, and this could be due to a lack of comprehensive ZIKV surveillance. Our aim was to determine the presence of antibodies to dengue, chikungunya, and Zika infections in adults from a suburban population in Sri Lanka. A total of 149 healthy adult volunteers over 18 years of age (mean age: 43±14 years, males - 43%), with no prior diagnosed arboviral infections and no history of overseas travel, participated in the study. ELISA and neutralization assays were carried out to detect past dengue, chikungunya, or Zika infections. A total of 94.6% (141/149) of the participants demonstrated dengue IgG antibodies, 37.5% (56/149) were positive for chikungunya IgG, and 5.3% (8/149) were positive for anti-ZIKV IgG antibodies. Neutralization assays confirmed ZIKV-specific antibodies in 6.7% (10/149), when 40/149 of the participating population were tested. This clearly demonstrated past ZIKV infections in this population. In addition, this study indicates that >90% of individuals had asymptomatic dengue but no serious symptoms. These results provide a cross-sectional view on the DENV, ZIKV, and CHIKV epidemic status and demonstrate a need for the implementation of enhanced surveillance and more effective measures against the spread of these arbovirus diseases.

Dengue Fever: A Case Study

Dengue is a pandemic that is brought on by the Dengue Virus (DENV), which is a single-stranded RNA (ribonucleic acid) virus. Dengue is also brought on by the bite of species in the Aedes family. Dengue, which is caused by the Dengue Virus, is the most common arboviral illness in the world and is a member of the Flaviviridae family. I present a study based on Dengue as a pandemic which outbreak on City Hospital of Delhi in the year 2010. Examining the clinical characteristics of dengue posi-tive cases, the prevalence of dengue diagnosis among patients with suspected dengue, and the effects of the aforemen-tioned on the environment and infectious illnesses. 4480 blood samples from clinically probable dengue fever patients were used in an enzyme-linked immunosorbent test (ELISA) to find dengue virus-specific IgM antibody protection. On 55 samples of C6/36 cell monolayers, virus isolation was carried out. The patient's application or the doctor might provide medical and public information about the patient. Results: Of the 4,480 blood samples tested, 1,800 blood samples (40.17%) were de-tected to be positive for the DENV with particular antibodies known as IgM antibodies. The most common group of single species of microorganism detected was DENV type 2. The conditions which were profusely detected were thrombocytopenia in which the blood platelet count observed is low and along with this Myalgia was also detected in which pain in the muscles is observed. In 32.4% and 17.9% of the 1,800-dengue fever IgM positive patients, respectively, low platelet count (thrombo-cytopenia) and muscle discomfort (myalgia) were noted. Together, these conditions accounted for 3% of the cases. Addition-ally, dengue hemorrhagic fever (DHF), which affects 10.3% of the 1,800 persons, has a fatality rate of 0.08%. Conclusions: Increased reporting due to changes in disease outbreaks, unprecedented rainfall, major infrastructure developments and improved medical facilities contributed to the shortage of dengue patients in 2010.

Treatment Dilemma in an Unusual Case of Dengue Fever with Cardiomyopathy and Nephropathy: A Case Report

Dengue is a viral illness in humans caused by the bite of infected Aedes mosquitoes, mostly Aedes aegypti and also Aedes albopictus. There are four serotypes of the Dengue virus that cause infection in humans and may lead to a variety of complications. Myocarditis and cardiomyopathy can occur in several viral and non viral infections, increasing morbidity and mortality. Nephropathy may also arise in dengue fever, causing complications. The case presented here involved both complications, nephropathy and cardiomyopathy, posing treatment challenges in terms of altering fluid and electrolyte status, which hindered fluid therapy as fluid overload would be detrimental. However, the complications were reversible with the normalisation of echocardiography and urea and creatinine levels. Long-term follow-up is necessary to monitor cardiac and renal function, as some patients may progress to Chronic Kidney Disease (CKD). The patient presented with fever, headache, vomiting, and haematuria, along with signs of fluid overload. There was a past history of fever, and since both Immunoglobulin G (IgG) and IgM Dengue antibodies were positive, this may be a case of a second episode of dengue fever causing complications. This case report emphasises the diagnostic and treatment challenges in a dengue patient with cardiomyopathy and nephropathy, where excessive fluid replacement may increase morbidity and mortality. Additionally, long-term follow-up of these patients is necessary.

268. Dengue - SARS-CoV-2 co-infection: Experience in hospitalized patients during COVID-19 pandemic

Abstract Background Dengue fever and COVID-19 co-infection constitute a significant public health concern in Latin America, becoming a clinical challenge to distinguish these two entities in early stages of the disease. Clinical outcomes of coinfected hospitalized patients have not been well established. Methods A cross-sectional study was conducted. We included suspected patients diagnosed with COVID-19/dengue co-infection admitted at Hospital Fundación Valle del Lili, Cali – Colombia, from March 2020 to March 2021. All dengue patients had positive NS1 and/or IgM dengue antibodies. SARS-CoV-2 infection was confirmed by RT-PCR or antigen rapid test from nasopharyngeal swab. Laboratory and clinical data were recollected from the clinical laboratory database, clinical charts, and institutional COVID-19 registry. Results A total of 90 COVID-19 patients were included. 72 patients were confirmed only with COVID-19, and 18 with dengue co-infection. Most patients were male: 46 (63.9%) vs. 13 (72.2%). None of these study patients were vaccinated against COVID-19 or dengue. The median time from symptoms onset and the diagnosis was five days, and fever was the most common symptom for both groups. There were significant differences between COVID-19 patients and coinfected patients regarding presence of dyspnea (22.2% vs. 61.1%; p=0.003), desaturation (13.4% vs. 53.3%; p=0.002) and a higher neutrophil/lymphocyte ratio (NLR) (3.84 vs. 5.59; p = 0.038). The co-infection was associated with a worse presentation of the COVID-19 infection (p=0.002), an increased requirement of initial supplemental oxygen therapy (p=0.007), mechanical ventilation (p=0.0004), ICU management at the admission (p=0.002), and ICU final management (p=0.002). Overall mortality in patients with co-infection was 44.4% vs. 6.9% in only COVID-19 infected patients (p< 0.001). Conclusion Despite the pandemic era, the possibility of co-infection of these two entities must be considered. Admitted coinfected patients were associated with worse clinical outcomes and higher mortality. According to our results, patients with co-infection present with severe respiratory symptoms and an elevated NLR. The impact of the Covid 19 vaccination on this coinfection is unknown. Disclosures Olga Agudelo, n/a, Fundación valle del lili: Board Member.

109. Seroprevalence of Protective Antibodies against Varicella, Hepatitis-A and Dengue among Indian Children, Adolescents and Adults

Abstract Background Varicella, Hepatitis-A and Dengue cause significant disease burden in our country. Estimation of age-wise seroprevalence of antibodies against these diseases not only help us in understanding age-specific incidence rates and susceptibility, but also help policy makers in deciding need and timing of vaccination. None of these vaccines are part of current national immunization program in India, yet. Methods In this observational cross-sectional study, apparently healthy children (9-12 years), adolescents (15-18 years) and adults (25-30 years) attending OPD of a tertiary care hospital in Northern India over two-year period (July 17- June 19) were enrolled after taking informed written consent, and their 3-ml venous blood sample was collected. Ethical clearance was obtained from Institute Ethics committee, before enrolling subjects. Serum was tested for IgG antibodies using specific commercial ELISA kits. Those who received received Hepatitis-A or Varicella vaccination in past were excluded from enrollment. Results Out of total 240 subjects (M:F=117:123) enrolled, 75 were children, 75 adolescents and 90 adults in specified age groups. Mean age in these three groups were 11.04, 16.52 and 26.53 years respectively. In our study, antibodies (IgG) against Varicella were >12 U/ml (seroprotective) in 36% (27/75), 74.6% (56/75), 64.5% (58/90) in children, adolescent and adults in specified age groups, respectively. Similarly, the antibodies (IgG) against Hepatitis-A were >10 U/ml (seroprotective) in above three groups were 68% (51/75), 85.3% (64/75), 95.5% (86/90). For dengue IgG antibodies also, seropositivity rates in above three groups were 37.3% (28/75), 62.7% (47/75), 53.3% (48/90). Conclusion Large proportion of children, adolescents and adults remain susceptible to Varicella and Hepatitis-A infection in India. Early childhood vaccination with Varicella and Hepatitis-A vaccines should be a part of National Immunization Programme in India, as a part of preventive strategy. Our study also showed a large proportion of children, adolescents and adults remain seronegative for Dengue antibodies in various age groups. Therefore, if currently available dengue vaccine (Dengvaxia) has to be used in our population, it can only be used after individual screening. Disclosures All Authors: No reported disclosures.

Frequency of Plasma Leak in Patients with Dengue Fever

Objective: To find out the frequency of plasma leak as evident by pleural effusion and ascites in the patients of dengue fever. Study Design: Cross-sectional study. Place and Duration: Medical unit of Hayatabad Medical Complex, Peshawar Pakistan from April 2021 to September 2021. Methodology: Patients diagnosed as having dengue fever based on positive dengue antigen (NS 1) test or antibodies serology on enzyme linked immunosorbent assay (ELISA) were evaluated. Plasma leak was defined as having ascites or pleural effusion evident on ultrasound or X ray chest of the patients with active dengue fever. Hematocrit of >50% in female and 55% in male was considered as indirect indicator of plasma leak. Results: In a total of 154 patients, 89 (57.8%) were male and 65 (42.2%) female with age ranging between 14 to 75 years while mean age was 40.6±15.54 years. The over all frequency of plasma leak as evident by ascites or pleural effusion was 44.2% (n=68. The minimum duration in which plasma leak was noted, remained 4 days while the maximum was 8 days after the start of illness. The duration of patient’s hospital stay was 5 to 17 days (mean 9.53±3.43 days). Practical implications: The frequency of plasma leak was higher in complicated dengue fever patients as compared to patients with less or no complications. Conclusion: Plasma leak is an important and frequent feature of dengue fever. X ray chest and ultrasound can detect majority of plasma leak in patients with hemoconcentration. Keywords: dengue fever, plasma leak, dengue NS1, dengue shock, dengue hemorrhage

Pattern of Aedes aegypti and Aedes albopictus Associated with Human Exposure to Dengue Virus in Kinshasa, the Democratic Republic of the Congo.

Dengue is a worldwide public health concern. The current study assessed the extent of human exposure to the dengue virus in relation to the distribution pattern of Aedes aegypti and Ae. albopictus in Kinshasa. Cross-sectional surveys were carried out in 2021 and 2022. The baseline entomological survey involved 19 municipalities using a grid cell sampling approach. All containers holding water were inspected for the presence of larvae in each grid. The collected larvae were kept in an insectary until the adult emergence for morphological identification. Four hundred febrile patients attending the hospital were screened for the presence of dengue antibodies (IgG, IgM) and NS1 antigen using a rapid diagnostic test (RDT) Biosynex®. Residences of positive cases were geo-referenced. We evaluated 1850 grid cells, of which 19.5% were positive for Aedes larvae. The positive grid cells were identified in the Ndjili (44.0%), Mont Ngafula (32.0%) and Ngaliema (26.0%), and Limete (32.0%) municipalities. The Ae. aegypti (11.2%) predominated in the northwestern, and Ae. albopictus (9.1%) appeared in the high vegetation coverage areas. Of 61 (15.3%) participants exposed to dengue, 8.3% presented acute dengue. Young, (6-17 years), male, and Mont Amba district participants were most exposed to dengue. In conclusion, dengue occurrence in Kinshasa overlaps somewhat the geographical and ecological distributions of Ae. aegypti and Ae. albopictus. Both species are not homogenously distributed, likely due to environmental factors. These findings can assist the targeted control activities.

To estimate the prevailing Serotype of dengue virus and IgM antibody in suspected dengue fever cases

Dengue virus infection a vector borne disease affecting more than 50 million people worldwide annually. It is distributed in tropical and subtropical regions of the world, abundant in urban and semi-urban areas. It is the disease that spreads by bite of Aedes aegypti and Aedes albopictus mosquitoes. The virus being a RNA virus belongs to Flaviviridae family. The four serotypes of Dengue virus are DENV-1, DENV-2, DENV-3, and DENV-4 which have distinct antigenicity complex.This study was conducted in Microbiology Department, Government Stanley Medical College, Chennai, during the period Jan 2018 to Dec 2018 with 120 blood samples from patients of suspected dengue fever. Samples were selected by stratified random sampling method into three strata and each strata consisting of 40 samples based on duration of fever. All the samples were subjected to procedure for both NS1 antigen and IgM antibodies.15 NS1 positives samples with duration of fever less than 5 days were serotyped by PCR. : A total of 18 cases had NS1 antigen, 26 cases had IgM antibodies and 27 cases had both. A combination of the two tests detected a total of 44 cases. The chance of detection of NS1antigen decreased with duration of fever and IgM antibodies increased with duration of fever. The serotyping detected were DENV1 and DENV3 NS1 antigen detection by ELISA is useful in early phase of infection. A combination of NS1 ELISA and IgM ELISA have high sensitivity depending upon the duration of illness. Detection of DENV1 and DENV3 by PCR procedure helps to know the presence of prevailing serotype in this particular region which would be a good guide to predict the recurrence of outbreak and for efficient prevention and management.

Molecular typing of dengue virus in Mizoram, Northeast India.

Dengue is an emerging vector-borne public health threat and characterization at the molecular level is important for proper management of the disease. The aim of the study is to examine the diversity of the dengue viral serotypes from a hilly mountainous region of Northeast India. Thirty-six blood samples that were positive for dengue virus IgM antibodies identified by the enzyme-linked immunosorbent assay (ELISA) method were collected and quantified for the IL6 gene expression by using reverse transcriptase polymerase chain reaction (RT-PCR). All the patients had dengue hemorrhagic fever (DHF); 12 samples had a monotypic infection and 14 samples had dual infection with various dengue virus (DENV) serotypes; one sample had triple infection with DENV-1, DENV-2, and DENV-3. This study identified DENV-1 as the major serotype in the state of Mizoram and it is the first report on the molecular typing of the dengue virus from the hilly mountainous state located in the Indo-Burma region bordering Myanmar and Bangladesh.

Sensitivity and specificity of DPP® Fever Panel II Asia in the diagnosis of malaria, dengue and melioidosis.

IntroductionRapid diagnostic tests (RDTs) that can facilitate the diagnosis of a panel of tropical infectious diseases are critically needed. The ‘DPP® Fever Panel II Asia’ is a multiplex lateral flow immunoassay comprising of antigen and IgM panels for the diagnosis of pathogens that commonly cause febrile illness in Southeast Asia.AimTo evaluate sensitivity and specificity of DPP® Fever Panel II for malaria, dengue and melioidosis.MethodologyWe conducted a cohort-based case-control study. Both cases and controls were derived from a prospective observational study of patients presenting with community-acquired infections and sepsis in northeast Thailand (Ubon-sepsis). We included 143 and 98 patients diagnosed with malaria or dengue based on a positive PCR assay and 177 patients with melioidosis based on a culture positive for Burkholderia pseudomallei. Controls included 200 patients who were blood culture positive for Staphylococcus aureus, Escherichia coli or Klebsiella pneumoniae, and cases of the other diseases. Serum samples collected from all patients within 24 hours of admission were stored and tested using the DPP® Fever Panel II Asia antigen and IgM multiplex assays. We selected cutoff values for each individual assay corresponding to a specificity of ≥95%. When assessing diagnostic tests in combination, results were considered positive if either individual test was positive.ResultsWithin the DPP® Fever Panel II antigen assay, a combination of pLDH and HRPII for malaria had a sensitivity of 91% and a specificity of 97%. The combination of dengue NS1 antigen and dengue antibody tests had a sensitivity of 61% and a specificity of 91%. The B. pseudomallei CPS antigen test had a sensitivity of 27% and a specificity of 97%. An odds ratio of 2.34 (95% CI 1.16-4.72, p=0.02) was observed for the association between positivity of CPS and mortality among melioidosis patients.ConclusionThe performance of the DPP® Fever Panel II Asia for diagnosis of malaria was high and that for dengue and melioidosis was relatively limited. For all three diseases, performance was comparable with other established RDTs. The potential operational advantages of a multiplex and quantitative point of care assay are substantial and warrant further investigation.

Look Out for Fever: Clinical Profile of Dengue in Young Adults in a Tertiary Care Center in North India.

Background Dengue fever (DF) is a common viral disease, clinical manifestations of which vary from influenza-like illness (DF) to life-threatening dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS). The aim of this article was to study the clinical profile of DF in young adults. Material and Methods This was an observational study conducted in the department of medicine over a period of 2 years (January 1, 2013-December 31, 2014). Patients aged between 18 and 30 years with serology proven (nonstructural protein 1 [NS1]/dengue immunoglobulin M [IgM]) DF were included in this study. The clinical and laboratory data was recorded and analyzed. Results Out of 418 cases, the incidence of DF, DHF, and DSS was 87.32, 7.66, and 5.02%, respectively. The most common presentations were fever (99.76%) followed by vomiting (29.43%), pain abdomen (17.94%), myalgias (13.16%), petechial rash (12.92%), and bleeding (10.29%). Dengue NS1 and IgM antibodies were positive in 87.3% and 88.12% of the patients, respectively. Ascites, splenomegaly, hepatomegaly, pleural effusion, gall bladder wall edema, and pericardial effusion were present in 8.13, 6.94, 6.70, 5.98, 2.63, and 0.72% of the patients, respectively. Complications included bleeding (10.29%), acute respiratory distress syndrome (1.67%), myocarditis (1.44%), seizures (1.44%), hemarthrosis (0.24%), and encephalopathy (0.24%). The mortality rate was 3.35% with death of 14 patients. Shock, bleeding, and elevated serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase levels predicted adverse outcome. Conclusion DF can present with a plethora of clinical manifestations in endemic areas. Adverse outcome is more likely if patients have elevated SGOT levels, shock, and bleeding. Continuous seroepidemiological surveillance is essential to control outbreak and minimize morbidity and mortality.

Co-infection with SARS CoV-2 and dengue virus with thrombocytopenia: A first case report from Nepal

Co-infection of COVID-19 with dengue infection is quite challenging to differentiate due to it’s overlapping clinical and laboratory manifestations. We report a 22-year-old female with presented to Civil Service Hospital, emergency department with complaints of persistent fever with multiple episodes of vomiting, headache and myalgia. On examination, she was ill-looking, dehydrated with a low blood. Reverse transcriptase – polymerase chain reaction of nasopharyngeal swab detected SARS CoV-2, and dengue antibodies IgM detected. She was conservatively managed in COVID-high care unit with regular laboratory monitoring of platelet level and discharged after ninth day of admission.