DEN-3 Serotypes Research Articles

IJCM_281A: Climatic Factors And Vector Indices In The Occurrence Of Dengue Fever Cases In Northern Kerala

Background: The number of dengue cases reported to WHO increased over 8-fold over the last two decades, from 505,430 cases in 2000, to over 2.4 million in 2010, and 5.2 million in 2019. The disease is now endemic in more than 128 countries with Asia representing ~70% of the global burden of disease. The transmission of dengue is dependent on various environmental factors and socio-demographic and economic factors. This study aimed to describe the climatic factors and vector Indices in the occurrence of dengue fever cases in Northern Kerala. Objectives: 1) To describe the epidemiological factors for occurrence of dengue cases in Northern Kerala. 2) Serological typing of Dengue confirmed cases admitted in a tertiary care Centre in Northern Kerala. Methodology: Data of dengue fever cases admitted to a tertiary care centre in Northern Kerala for a period of one year were collected from Regional Prevention of Epidemics and Infectious Diseases Cell (R-PEID CELL). Vector indices data obtained from District vector control unit. Serology details were collected from Microbiology lab of the tertiary centre and Regional Virus Research and Diagnostic Laboratory (RVRDL). Geographical mapping and analysis of occurrence of dengue cases with rainfall done. Results: Total 518 cases were admitted to the tertiary centre during January 23-October 23. 68% Male and 32% female.77.7% Cases were reported from Kozhikode district.25 % cases were belonging to age group 20-29. Admission of cases were more during October followed by August. Serological typing of sub sample showed DEN2 as the predominant serotype. DEN1 and DEN3 serotypes were also identified. Conclusion: There is increased case transmission occurred during rainy season i.e. in North East and South West Monsoon which is in accordance with district vector indices data. DEN2 was the predominant serotype followed by DEN1.

Dengue Fever Outbreak Investigation in Werder Town, Dollo Zone, Somali Region, Ethiopia.

Dengue fever (DF) is a mosquito-borne disease caused by the dengue virus. DF is endemic to many tropical and subtropical countries around the world. In Ethiopia, DF emerged in 2013 and caused a serious public health problem. We investigated the outbreak to describe by time, place, person, and to identify risk factors associated with the outbreak in Werder town, Dollo Zone, Somali Region, Ethiopia. Descriptive and case-control studies (1:2 ratio) were conducted. We used the World Health Organization (WHO) case definition to identify cases in Werder town from December 10, 2020, to January 4, 2021. Controls were selected from the same town that did not suffer from DF. Serum samples were tested by reverse transcription polymerase chain reaction (RT-PCR) to detect the dengue virus and to identify serotypes. A structured questionnaire was used to collect socio-demographic, behavioural, and environmental characteristics. We identified a total of 57 cases and 114 controls. The overall attack rate was 334.41/100,000 with a zero case fatality rate. Six out of twenty serum samples tested positive for the DEN-3 serotype. In multivariate analysis, not hearing of DF (Adjusted odd ratio (AOR): 2.2, 95% CI: 1.015-4.701), not knowing the mode of transmission (AOR: 2.9, 95% CI: 1.338-6.831), not using long-lasting insecticidal net (LLITN) (AOR: 4.4, 95% CI: 1.592-12.330) and not spraying insecticide (AOR: 3.6, 95% CI: 1.591-8.098) were statistically significant risk factors associated with DF outbreak. However, wearing long sleeves (AOR: 0.435, 95% CI: 0.206-0.918) was a protective factor for the DF outbreak. DF outbreak in Werder town has been confirmed. The present study provides evidence-based information regarding the identified risk factors that have contributed to the occurrence of DF outbreaks. We recommended implementing vector control measures and strengthening dengue surveillance systems is strongly advised.

Molecular and Haematological Analysis of Dengue Virus-3 Among Children in Lahore, Pakistan

Background: Dengue virus (DENV) is an RNA virus belonging to the family Flaviviridae of the genus Flavivirus with worldwide distribution. Dengue fever is caused by any of four closely-related serotypes DENV, an emerging pandemic-prone viral disease in many regions of the world. Objectives: The present study aimed to determine the prevalence of dengue virus genotypes and serotypes in children aged below 15 years in Lahore, Pakistan. Methods: In this study, 112 serum samples were collected from clinically suspected dengue fever patients from March 2017 to December 2018 at different tertiary care hospitals in Lahore, Pakistan. Regarding the patients’ age, the samples were divided into four groups from A to D (i.e., 0 - 1, 1 - 5, 5 - 10, and 10 - 15 years of age). Rapid immuno-chromatography (ICT) test was conducted on the collected serum samples, followed by quantitative RT-PCR for serotype of dengue virus. Results: Out of 112 samples, 34 samples were diagnosed as DENV positive by the rapid ICT screening method. No virus was detected in groups A and B, while three samples were positive in group C (1 boy and two girls), and 31 samples (23 boys and 8 girls) were positive in group D. The results of quantitative RT-PCR exclusively showed DEN-3 serotype in all the ICT positive samples. The results indicated that the prevalence of DEN-3 serotype in children was 100%, indicating that DEN-3 serotype might cause severe epidemics in the future in Lahore, Pakistan. Hematological analysis revealed an increase in hematocrits in 41.1% dengue-positive cases. Leucopenia was prominent in 79.4% of the cases, while Thrombocytopenia was reported in 70.5% of the participants. The biochemical analysis also indicated an increase in liver enzymes in patients (ALT 88%, AST 79%), while the lower levels of cholesterol (69 %) and serum albumin (25%) were also observed. Conclusions: Dengue virus spreads and grows quickly worldwide over a highly short time interval. Dengue fever claims for a significant number of lives. This study would help individuals know about the status of laboratory parameters in dengue fever and detect how to overcome the prevalence of Dengue virus.

Retrospective analysis of dengue mortalities over a 32 month period in a state hospital, Malaysia

Background: Dengue is endemic in Malaysia with 147 deaths and a case fatality rate of 0.18% in 2018. Our aim is to study the complications and predominant clinical manifestations associated with dengue mortality and correlate the mortalities with the dengue serotypes over 32 months. Methods and materials: A retrospective review and descriptive analysis of medical records of laboratory confirmed dengue mortalities in Hospital Tengku Ampuan Rahimah, Klang, from January 2017 to August 2019 was performed. Results: A total of 15 mortality cases over 32 months, of which 73% were males. Mean (SD) age was 43.69 (15.9) years. Median (IQR) days of illness were 4 (5–2.5) days. 80% had bleeding and leaking manifestations. 40% of cases had occult bleed while 26.7% bled from the gut and oral cavity. 60% of mortalities showed clinical and radiological signs and symptoms of pleural effusion and 61% developed ascites respectively. 93.3% (n = 14) had serum pH less than 7.35 and 100% had lactate more than 2. Serum ferritin was >10,000 ng/mL in 73% of the mortalities. 93.3% (n = 14) had renal failure requiring CRRT (continuous renal replacement therapy), 93.3% had severe hepatitis and 53% with myocarditis. CNS (central nervous system) manifestations were documented in 27% of mortalities. Dengue serotype were only recovered in 13 patients in which 46% (6 of 13) were infected with DEN-2, 31% (4 of 13) DEN-3 and 23% (3 of 13) DEN-1. However, the predominant serotype causing mortality according to years was DEN-3 (50%) in 2017, DEN-1 (66%) in 2018 and DEN-2 (83%) in 2019. We also observed that hemophagocytic lymphohistiocytosis (HLH) manifestations occurred in 100% DEN-2 and 75% DEN-3 fatality cases. In addition, DEN-3 serotype infection was also associated with myocarditis (100%) and encephalitis (50%). Conclusion: This study highlights the importance of recognising dengue, its manifestations and identifying its complications earlier to manage these cases better, hence reducing mortality. Continuous surveillance of dengue serotype provides information about the dynamic nature of dengue virus serotype circulation and its role in emerging of outbreaks.

Circulating Dengue Serotypes in Central Delhi during 2015 Outbreak

Introduction: Dengue fever is caused by an arthropod borne dengue virus. Delhi has witnessed various outbreaks in the last two decades. All the four dengue serotypes are being reported to circulate during each outbreak with predominance of one or more. Each year the prevalent circulating serotype changes. This study was planned to identify the predominant circulating dengue serotype during 2015 Delhi outbreak. Material and Methods: Venous blood was collected from the 150 suspected adult patients attending the outdoor department of medicine. Dengue fever was diagnosed using NS-1 antigen ELISA and dengue serotypes were detected using conventional RT-PCR among 15 randomly selected NS-1 antigen positive sera. Result: Out of 150 suspected cases, 44 were positive for dengue NS-1 antigen. RT-PCR among 15 positive sera detected five DEN-1, three DEN-2 and seven DEN-3 serotypes. Conclusion: The prevalent circulating dengue serotype in central Delhi during 2015 outbreak was DEN-3 followed by DEN-1. How to cite this article: Abhishek KS, Kumar N, Chakravarti A, Baveja CP. Circulating Dengue Serotypes in Central Delhi during 2015 Outbreak. J Adv Res Med 2020; 7(1): 1-4. DOI: https://doi.org/10.24321/2349.7181.202001

Frequency of dengue infection in febrile patients attended Dhaka Medical College Hospital during January to December, 2018

Introduction: Dengue is a major public health concern in our country. The alarming thing is that the seasonal trend of dengue infection is changing with time in Bangladesh due to climate change and unplanned urbanization. Our study was conducted to determine the frequency of dengue virus infection among the febrile patients in 2018 at Dhaka Medical College Hospital (DMCH) and to observe the seasonal trend.
 Materials and Methods: The study was carried out on 899 febrile patients attended in DMCH from January to December, 2018. Whole blood samples were collected and sera were tested for dengue NS1 antigen and anti-dengue IgM antibodies using commercial test kits (NS1 by OMC Healthcare (Pvt.) Ltd & IgM antibody by Omega Diagnostics Ltd.), respectively. All negative dengue cases were tested for anti Chikungunya antibody to exclude chikungunya.
 Results: Of the total 899 febrile patients, 350(38.93%) were positive for Dengue infection. Out of them 264(75.43%) were positive for NS1, 82 (23.43%) were positive for IgM and 4 (1.14%) were positive for dengue NS1antigen + anti dengue IgM antibody. More than 50% patients belonged to age group 15-29 years. Males were predominant. More than 60% cases were detected in the post monsoon season.
 Conclusion: Highest dengue cases were detected in this year in comparison to the previous year’s probably due to re-emergence of DEN-3 serotype. Due to pattern of climate change, seasonal trend of dengue infection was not maintained. Moreover, unplanned urbanization and poor solid waste management have worsened the situation more.
 J Dhaka Medical College, Vol. 28, No.1, April, 2019, Page 105-111

Largest dengue outbreak of the decade with high fatality may be due to reemergence of DEN-3 serotype in Dhaka, Bangladesh, necessitating immediate public health attention.

Largest dengue outbreak of the decade with high fatality may be due to reemergence of DEN-3 serotype in Dhaka, Bangladesh, necessitating immediate public health attention.

Involvement of dual serotypes during a severe dengue outbreak in Wadi area, Nagpur district, Maharashtra 2017.

An outbreak of dengue-like illness was reported from Wadi area within the Nagpur Municipal Corporation during September-October 2017 with five deaths. Major symptoms reported were high fever (103-106 oF), acute joint pains, myalgia, drowsiness, breathlessness, etc. An investigation was conducted to confirm the etiological agent, its characterization and the vectors involved in the outbreak. Serological analysis was conducted to detect dengue (DEN)/chikungunya IgM antibodies in 158 sera samples. Nested-PCR was carried out to serotype eight ELISA positive samples. Adult and larval mosquito collections were conducted in the affected areas to determine species composition and mosquito density. Dengue IgM antibodies were detected in 44 sera samples. Molecular typing revealed involvement of DEN-2 and DEN-3 serotypes. Dengue hemorrhagic fever symptoms were observed in two patients. Aedes aegypti breeding was found rampant with Breteu index and house index ranging from 23 to 70 and 17 to 56, respectively. Major breeding habitats encountered were, used tyres, cement tanks and refrigerator trays. Clinical symptoms, detection of anti-DEN IgM antibodies in high number of samples and heavy breeding of Ae. aegypti confirmed it was a dengue outbreak.

Epidemiological and Entomological Investigation of Dengue Fever Outbreak in South Nias District, North Sumatera Province, Indonesia, 2016

Dengue infection continues to present as a serious public health problem in North Sumatera, Indonesia. A dengue fever outbreak was reported in Teluk Dalam Subdistrict, South Nias District, North Sumatera during February 2016. An epidemiological investigation was conducted to identify the risk factors and recommend control measures. An observational study with a matched case-control design was conducted. A case was defined as a resident of Teluk Dalam District who had suffered two or more clinical symptoms of fever, headache, pain behind eyes, muscle and joint pain, and rash from 14 Feb to 16 Mar 2016. Blood samples were tested to confirm the diagnosis and serotype identification. Total 68 cases and 68 controls were included in the matched case-control study. The case fatality rate was 2.9%, age ranged from six months to 51 years (median 25 years). Three out of six cases were tested positive for DEN-3 serotype. In multivariate analyses, not eliminating mosquito breeding sites routinely (adjusted odds ratio = 3.7, 95% CI = 1.48-9.46) and having habit of hanging worn clothes (adjusted odds ratio = 2.9, 95% CI = 1.21-6.96) were risk factors. Elimination of mosquito breeding sites routinely, proper management of worn clothes, and conducting strict surveillance for dengue infection were recommended.

Identification of Prevalent Dengue Serotypes by Reverse Transcriptase Polymerase Chain Reaction and Correlation with Severity of Dengue as per the Recent World Health Organization Classification (2009)

Context: A definite link between distinct dengue serotypes and severe clinical manifestations has not been established yet. The WHO classification (2009) of dengue is more competent in diagnosing severe cases compared to traditional (1997) classification. Aims: This study aimed to identify prevalent dengue serotypes and to correlate the severity of dengue with the dengue virus (DENV) serotypes in target population as per the recent WHO classification (2009). Settings and Design: A retrospective comparative observational study was conducted from 1st January 2015 to 31st December 2015. Subjects and Methods: We tested 242 dengue NS-1 antigen ELISA-positive cases for serotyping by dengue reverse transcriptase-polymerase chain reaction (RT-PCR). Severity of each dengue case confirmed by RT-PCR was determined as per the recent WHO classification (2009). Results: On the basis of RT-PCR, dengue infection was confirmed in 135 (55.78%) patients. DEN-3 was the most common serotype found in 71 (52.6%) patients, followed by DEN-2 serotype with 44 (32.6%) patients. Nearly 2.22% cases of DEN-2 and 2.96% cases of DEN-3 serotype were having dengue with warning signs. Severe dengue was found in 2.22% cases of DEN-2 and 5.18% cases of DEN-3 serotypes. Thrombocytopenia, haemorrhagic manifestations and atypical presentations were found most commonly in DEN-3 followed by DEN-2 serotype. Coinfection with more than one serotype was observed in our study, with the most common coinfection pattern being DEN-2 and DEN-3 serotypes. Conclusions: DENV-3 and DENV-2 serotypes are prevalent in the region and are associated with a more serious clinical profile than other serotypes.

ANALISIS FILOGENETIK DENGUE DI INDONESIA

Molecular epidemiology is needed to solve the problem for endemic Dengue Hemorrhagic Fever in Indonesia.This research has been carried out consisting of 525 Dengue Hemorrhagic Fever sera, according to the WHO criteria.These sera were collected from 19 cities in Indonesia comprising the islands of Sumatera, Batam, Kalimantan, Sulawesi, Papua, Java,Bali and Lombok from 2003 until 2005. The immune response profile was as follows 57.14% (300/525) secondary infection, 12.57%(66/525) primary infection, 4.20% (22/525) equivocal and 26.09% (137/525) negative. From 192 PCR samples, 100 (52%) serawere positive, consisting of 65% DEN-2, 15% DEN-3, 12% DEN-4 and 8% DEN-1. Homology analysis showed nucleotide differences incapsid region DEN-2 serotypes, while DEN-3 serotypes were relatively consistent. Phylogenetic analysis using envelope (E) gene revealedthat the Cosmopolitan genotype from Gorontalo in 2005, is currently circulating locally, with the potential to cause a severe hemorrhagicdisease. Members of this genotype were closely related to viruses from Malaysia, Singapore, Thailand, Philippines and Australia. Theisolate from Jakarta, 2003 showed DEN-3 with I genotype. This genotype was similar to the isolate from Indonesia 1978, 1985, andalso from Thailand 1992, Philippines 1997, and Fiji 1992. These results showed Cosmopolitan genotype from DEN-2 was similar toSoutheast Asia countries. It was also revealed that genotype-I from DEN-3 showed no change over the years since 1978.

Modeling and experimental assessment of a buried Leu–Ile mutation in dengue envelope domain III

Envelope protein domain III (ED3) of the dengue virus is important for both antibody binding and host cell interaction. Here, we focused on how a L387I mutation in the protein core could take place in DEN4 ED3, but cannot be accommodated in DEN3 ED3 without destabilizing its structure. To this end, we modeled a DEN4_L387I structure using the Penultimate Rotamer Library and taking the DEN4 ED3 main-chain as a fixed template. We found that three out of seven Ile387 conformers fit in DEN4 ED3 without introducing the severe atomic clashes that are observed when DEN3 serotype’s ED3 is used as a template. A more extensive search using 273 side-chain rotamers of the residues surrounding Ile387 confirmed this prediction. In order to assess the prediction, we determined the crystal structure of DEN4_L387I at 2 Å resolution. Ile387 indeed adopted one of the three predicted rotamers. Altogether, this study demonstrates that the effects of single mutations are to a large extent successfully predicted by systematically modeling the side-chain structures of the mutated as well as those of its surrounding residues using fixed main-chain structures and assessing inter-atomic steric clashes. More accurate and reliable predictions require considering sub-angstrom main-chain deformation, which remains a challenging task.

Multiple dengue serotypes and high frequency of dengue hemorrhagic fever at two tertiary care hospitals in Lahore during the 2008 dengue virus outbreak in Punjab, Pakistan

The objective of this study was to investigate the clinical characteristics of patients with dengue viral infection during the 2008 outbreak in Lahore in order to better understand the clinical pattern and severity of disease in Lahore. We analyzed the clinical characteristics of 110 patients infected with dengue virus; data were collected on standardized data collection sheets at two tertiary care hospitals from September to December 2008. Dengue infection was confirmed serologically or by real-time polymerase chain reaction (RT-PCR). Out of the total of 110 dengue infected patients, 70 were male and 40 were female. The most common symptoms included fever (100%), myalgia (68.2%), headache (55.5%), nausea (39.1%), skin rash (53.6%), mucocutaneous hemorrhagic manifestations (58.2%), and ocular pain (20%). Classic dengue fever (DF) was seen in 41.8% of the patients, 56.4% had dengue hemorrhagic fever (DHF), and only 1.8% developed dengue shock syndrome (DSS). The mean duration of fever was 6 days. Thrombocytopenia, leukopenia, and abnormal aspartate aminotransferase (AST)/alanine aminotransferase (ALT) were more frequently encountered in DHF and DSS as compared to DF. Viral RNA detection was done by RT-PCR in 17 patients. Ten patients had DEN4, five had DEN2, and two had DEN3 serotypes. The majority of the patients recovered completely without complications. The high frequency of DHF during the 2008 outbreak and the presence of three different dengue serotypes, emphasize the need to prevent and control dengue infection. Health authorities should consider strengthening surveillance for dengue infection, given the potential for future outbreaks with increased severity. It is also suggested that primary care physicians should be educated regarding recognition of DHF and to identify patients at high risk of developing DHF and DSS.

Field- and laboratory-based active dengue surveillance in Chennai, Tamil Nadu, India: Observations before and during the 2001 dengue epidemic

Dengue cases are reported every year in the city of Chennai, Tamil Nadu, India. Since April 2001, longitudinal field- and laboratory-based active dengue surveillance has been carried out in Chennai to study dengue trends. A serologic survey of people in Chennai using the hemagglutination inhibition test (HIT) was performed to determine evidence of prior exposure to dengue virus infections. Dengue virus infections and their serotypes were demonstrated in vectors. The serum samples from clinical dengue patients were analyzed for dengue virus-specific immunoglobulins M (IgM) and G (IgG) antibodies by 2 commercial ELISA kits. There was an increase in the percentage of children with monotypic antibody responses to dengue in the later survey (April 2.2%, September 9.93%). DEN-3 serotype infections were demonstrated in male Aedes aegypti mosquitoes collected in September 2001. Dengue virus infection was diagnosed in 74.5% (143/192) of cases. While dengue-specific IgM responses were predominant among infants with dengue fever, IgG and mixed responses (M + G) were seen in 85% of the children with severe forms of dengue. The findings from these investigations suggest that antibody surveys in children and virus detection in vectors may be included as early warning system parameters in laboratory-based proactive dengue surveillance.

Dengue virus type 3 isolation from Aedes aegypti in the municipality of Nova Iguaçu, State of Rio de Janeiro.

In a prospective field study conducted from July 2000 to June 2001, adult Aedes aegypti and Ae. albopictus mosquitoes were caught from the municipality of Nova Iguaçu, State of Rio de Janeiro, Brazil. Virus isolation in Ae. albopictus clone C6/36 cell line and a semi-nested reverse transcription-polymerase chain reaction detected only dengue virus type 3 in three pools of Ae. aegypti, despite the co-circulation of DEN-1, DEN-2 and DEN-3 serotypes in that area. No viruses were detected in Ae. albopictus mosquitoes. This virological surveillance consists in a sentinel system alerting for dengue outbreaks.

Dynamics of dengue virus circulation: a silent epidemic in a complex urban area.

Serotypes of dengue DEN-1 and DEN-2 have been reported in much of Brazil over the last 15 years, and DEN-3 serotype was only recently detected. This prospective study was conducted in Salvador, a large city in north-east Brazil, where two epidemics were previously recorded (DEN-1 and DEN-2). We obtained the seroprevalence and 1-year incidence of dengue infections in the population of 30 sampling areas of Salvador and analysed the relationship between intensity of viral circulation, standard of living and vector density. High seroprevalence (68.7%) and annual incidence (70.6%) of infection for one or both circulating serotypes (DEN-1 and DEN-2) were found. High rates of transmission were observed in all studied areas, from the highest to the lowest socio-economic status. The mean PI (Premise Index) for Aedes aegypti was 7.4% (range 0.27-25.6%). Even in the areas with the lowest PI (</=3%) the observed seroincidence was 54.6%. These findings highlighted the existence of a silent epidemic during a period perceived by the Health Services as of low endemicity, indicating the strength and speed of dengue transmission in the city of Salvador.