Secondary Dengue Infection Research Articles

Comparison of the Hemagglutination Inhibition Test and IgG ELISA in Categorizing Primary and Secondary Dengue Infections Based on the Plaque Reduction Neutralization Test.

Secondary dengue infection by heterotypic serotypes is associated with severe manifestations of disease, that is, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The World Health Organization (WHO) has recommended criteria based on the hemagglutination inhibition (HI) test to distinguish between primary and secondary dengue infections. Since the HI test has practical limitations and disadvantages, we evaluated the accuracy of WHO HI criteria and compared it with criteria based on an IgG enzyme-linked immunosorbent assay (ELISA) using a plaque reduction neutralization test (PRNT) as the gold standard. Both WHO HI criteria and IgG ELISA criteria performed strongly (16/16) in determining primary infection. However, to determine secondary infection, the IgG ELISA criteria performed better (72/73) compared to the WHO HI criteria (23/73).

Differentiating primary and secondary dengue infections: Why and how?

Differentiating primary and secondary dengue infections: Why and how?

Immunoglobulin A Antibody Responses in Patients with Primary or Secondary Dengue Infections

IgM serological diagnostic plays an important role in the dengue epidemiological surveillance. However, IgA has been identified as a possible diagnostic marker for early stage and recent infections. The aim of this study was to know the IgA response in dengue patients in relation to type of infection, serotype specificity and role as early and recent infection marker. IgA behavior in dengue patients, using a method defined as Indirect Sandwich ELISA-IgA (ELISA-IgA) and Capture IgM ELISA (MAC- ELISA) as reference assay was studied. The sensibility and specificity of the system were 91.06% and 83.73% respectively. In acute phase of illness, IgA was only detected in secondary cases with 32.3%. IgM appears later than IgA in secondary cases. No significant differences in IgA or IgM responses between primary and secondary cases were found in samples collected after day 5 of onset of symptoms. In days 41-54, the percentage of IgA was lower respect to IgM. IgA was detected until day47 inprimary and until day50 insecondary cases. An elevated cross-reactivity in IgA was observed between dengue serotypes contrary to IgM. The usefulness of IgA, as alternative early diagnostic tool, could be influenced by the absence or very low percentages of positives cases in the first four days of onset of symptoms. However, for definition of secondary infection could be important. IgA could be an alternative tool, better than IgM, as recent infection marker for dengue fever, but this requires more studies in future investigations.

Dengue Outbreak in Martin County, Florida in 2013

Following a 2013 outbreak of dengue serotype 1 in Martin County, Florida, plasma samples from individuals with suspected dengue illness were tested for serotypespecific neutralization of dengue viruses 1-4. Titers and seroprevalence in these suspected cases from Florida were compared to those from (1) healthy donors from the U.S. and (2) dengue-suspected and dengue-confirmed samples collected from dengue-endemic regions during outbreaks in Puerto Rico in 2010 and Brazil in 2014. By dengue plaque reduction neutralization titer assays, we confirmed that four of the nine suspected individuals from Martin County Florida had been exposed to dengue virus serotype 1, and that these were primary dengue viral infections. Furthermore, primary and secondary dengue viral infections were observed in the Brazilian cohort, and a high incidence of secondary infections was observed in the Puerto Rican samples. Routine serotype-specific surveillance may be needed to continue monitoring establishment of dengue serotype 1 and

Prevalence of dengue viral and malaria parasitic co-infections in an epidemic district, Angul of Odisha, India: An eco-epidemiological and cross-sectional study for the prospective aspects of public health.

The co-existence of dengue and malaria infection in an individual and the primary and secondary dengue infection during co-infection were assessed. Over 1 year, 1980 blood samples were collected from suspected cases of dengue fever and analyzed by rapid diagnostic test (RDT), enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods to detect dengue infection. RDT and microscopic methods were used to detect malaria. Of the 1980 samples, only 22 (3.0%) cases were identified as dengue-malaria co-infection cases, out of which 13 were male and 9 were female. The highest number of confirmed cases were found during the hot and humid months of September and October (7 cases, 31.8%) and within the over 15 years age group. Of the cases of co-infection, dengue primary infection (21 cases, 95.5%) was significantly more common than dengue secondary infection (1 case, 4.5%) among all of the age groups. There were 12 cases of Plasmodium falciparum and 10 cases of Plasmodium vivax infection among malarial cases. A high prevalence of concurrence of dengue and malaria infection was recorded in this ecosystem. In light of the severity of co-infection and overlapping symptoms, a multidimensional diagnostic approach is suggested.

Secondary dengue virus infections during the 2009 outbreak in Buenos Aires.

To evaluate the occurrence of secondary dengue virus (DENV) infections during the 2009 outbreak in a non-endemic area. Viral loads were evaluated in serum from acute-phase patients, comparing primary and secondary infection. Serum samples from patients with clinical diagnosis of suspected dengue were referred to the Virology Laboratory at 'Ricardo Gutiérrez' Children's Hospital. Dengue-positive samples were classified as primary or secondary DENV infections through serological methods (anti-DENV IgM and IgG). Viral loads were measured by quantitative real-time PCR (qRT-PCR) in samples obtained in the first 5 days of infection. Statistical analyses were performed to evaluate factors that might correlate with differences in the viral load of primary or secondary infection. A total of 229 DENV cases were confirmed; among them, 22.7% were secondary infections. No significant differences were found between the viral load of primary and secondary infections. We detected a high percentage of secondary DENV infections in a non-endemic area; this finding might correspond to socio-demographic characteristics of the group under study or indicate a previous cryptic DENV circulation causing inapparent infections.

An epidemiological study of dengue in Delhi, India

Delhi, the capital of India, is an important metropolitan hub for major financial and sociocultural exchanges, offering challenging threats to current public health infrastructure. In recent past, an upsurge of dengue cases in Delhi posed a significant menace to the existing dengue control policies. To reform the control strategies and take timely intervention to prevent future epidemics, an epidemiological study on the proportion of both asymptomatic and symptomatic dengue infections in selected population was conducted. The aim of the study was to investigate and assess the epidemiology of dengue infection and to estimate the proportion of asymptomatic and symptomatic dengue infections in Delhi. In this study, around 50 confirmed dengue cases, a total of 2125 individuals as household and neighbourhood contacts, with or without dengue febrile illness, were finger pricked and serologically detected as dengue positive or negative using SD Duo Bioline Rapid Diagnostic Test (SD Inc, Korea) with NS1, IgM & IgG combo test, which detected dengue virus antigen and antibodies to dengue virus in human blood. Out of 2125 individuals, 768 (36.1%) individuals showed positive dengue test with past (25.5%), primary (1.88%) or secondary (8.8%) dengue infections. Higher percentage of IgG was found in age groups 15–24 years and 25–50 years (36% each). Infants (<1 year) presented higher incidence of new infections (22% of NS1+IgM positives) as compared to adults. Further analysis revealed that out of the 226 newly infected cases (including NS1 and IgM positives), 142 (63%) were asymptomatic and 84 (37%) were symptomatic, as per WHO guidelines. Our findings also suggest that out of the total population screened, 10.6% dengue infection was either primary or secondary. On the basis of these results, it may be hypothesized that there are large number of asymptomatic dengue infections in the community as compared to reported symptomatic cases in Delhi. For the effective control of dengue transmission in such community like Delhi where dengue epidemics have frequently been encountered, it is essential to ascertain the proportion of asymptomatic dengue infections which may act as a reservoir for dengue transmission, as well as threat for developing dengue haemorrhagic fever (DHF).

Endothelial Cell Sensitization by Death Receptor Fractions of an Anti-Dengue Nonstructural Protein 1 Antibody Induced Plasma Leakage, Coagulopathy, and Mortality in Mice.

The mechanisms leading to the life-threatening dengue hemorrhagic fever (DHF) remain elusive. DHF preferentially occurs during secondary dengue infections, suggesting that aberrant immune responses are involved in its development. We previously demonstrated that the autoantibodies elicited by dengue virus (DENV) nonstructural protein 1 (NS1; anti-NS1 Igs) induce plasma leakage and mortality in mice with warfarinized anticoagulant suppression. However, the involved pathogenic Ig fractions of anti-NS1 Igs remain unclear. In this study, the autoreactive Igs in patients with DHF and in NS1-immunized rabbits crossreacted with TNF-related apoptosis-inducing ligand receptor 1 (death receptor [DR]4). Challenges with the DENV in a subcytotoxic dose sensitized endothelial cells to apoptosis. Treatments with the autoantibodies induced proapoptotic activities and suppressed the surface expression of endothelial anticoagulant thrombomodulin. Combined treatments comprising the DENV and DR4 affinity-purified fractions of anti-NS1 IgGs (anti-NS1-DR4 Ig), but not preimmune control IgGs, in subcytotoxic doses led to apoptosis in endothelial cells. Treatments with the anti-NS1-DR4 Ig led to plasma leakage, coagulopathy, and morality in mice with warfarinized anticoagulant suppression. These results suggest that DR4-induced endothelial cell sensitization through NS1-elicited autoantibodies exacerbates anticoagulant suppression, vascular injury, and plasma leakage. Detecting and blocking anti-DR Igs in patients may be novel strategies for managing severe DENV infection.

Does immunoglobulin therapy have a role in treating Dengue virus infection with induced systemic capillary leak syndrome?

The report of severe cardiovascular changes in the eight children with secondary dengue infection and dengue shock syndrome (DSS) by Kositseth et al. [1] was consistent with systemic capillary leak syndrome (SCLS). It is thought to be distinct from classical dengue fever (DF). However, clinicians working in endemic areas need to be aware that such textbook presentations may not be applicable in this age when extremes of climate and increase in air travel have complicated the infection demographics in clinical medicine. A report published in March 2012, showed the high prevalence of SCLS among travelers, a third of which were primary dengue cases and 85% also had classical DF [2]. It is interesting to hypothesize that patients co-infected with two serotypes of dengue virus (DENV) may develop multiple organ failure and DSS, but no specific reports on these complications are available from Asia (DENV-2/-3 and DENV-3/-4), or the Americas (DENV-2/-3 and DENV-3/-4). Whether complications from multiple organ failure and DSS was the case in the recent epidemic of dengue virus related deaths in children and adults from Eastern India during the rainy season/autumn 2012 remains to be proven [3]. As with most infectious pathogens, homologous DENV genetic recombination events have been widely reported [4,5], but fortunately, there have not been any reports of heterologous DENV-serotype recombination events. Such events would result in new chimeric strains and the immunological hypothesis of antibodyenhanced disease and multi-organ failure would be the most likely explanation [6]. Does high-dose intravenous immunoglobulin (hdIVIG) sourced from the local donor population, rather than imported, offer a viable treatment option in DENV-related SCLS? A publication from the European Registry of patients with idiopathic SCLS showed improvement after treatment with hdIVIG [7]. Treatment with hdIVIG certainly remains a feasible option with viral-related autoimmune manifestations such as Kawasaki disease, but will this treatment prove effective against the dreaded thrombocytopenia and SCLS in DENV infection? [8,9] Only a multi-center clinical trial can answer this question. In the interim time, civic and health authorities must work together with entomology and virology centers to prevent unnecessary deaths from this vector-borne disease.

Immunoglobulin G (IgG) to IgM ratio in secondary adult dengue infection using samples from early days of symptoms onset.

BackgroundDengue virus (DENV) infection is an emerging arboviral infection in tropical and sub-tropical countries in South-East Asia, the Western Pacific and South and Central America. Secondary DENV infection is the most widely accepted risk factor for the development of severe forms. Methods to discriminate primary and secondary DENV infection may be of great prognostic value. ELISA based detection of specific antibodies (IgG and IgM) to the four DENV serotypes is valuable for detemination of primary or secondary infection. Several studies had been performed to discriminate primary and secondary DENV infection using the ratio of IgG and IgM at the various days of symptoms onset. The aim of this study is to determine the best cut-off point of IgG to IgM ratio is able to discriminating secondary from primary DENV infection in adult using samples from early days of symptoms onset.MethodsThis prospective cohort study on 48 adult patients with DENV infected patients on the period of August 2011–January 2012 in 5 out-patient settings health facilities in Tangerang district, Banten province, Indonesia with chief complaint of fever less than 3 days. Datas were collected on the day the patients attended health facilities, consisted of demographic, clinical, laboratory, and serological data. Serological data from 48 serum sample from adult patients were evaluated using Focus Diagnostics Dengue Virus IgM and IgG Capture DxSelect™ ELISA Kits to determine IgG, IgM index values and SD Bioline Dengue Duo™ Rapid Tests to determine NS1, IgG, and IgM result.ResultsAccording to NS1, IgG and IgM results, 36 patients were classified as secondary infection, 12 were primary Infection. The mean (SD) of IgG/IgM ratios for secondary and primary infection were 3.28 (0.54) and 0.18 (0.11) consecutively. The IgG/IgM ratio of ≥ 1.14 confirmed secondary infection with sensitivity of 80.56 %, specificity 91.67 %, accuracy level 83.33 %, and likely hood ratio of (LR) 9.67.ConclusionThe IgG/IgM ratio of ≥ 1.14 as the best cut off point to determine secondary DENV infection in early days of symptoms onset.

Higher levels of dengue-virus-specific IgG and IgA during pre-defervescence associated with primary dengue hemorrhagic fever.

Dengue hemorrhagic fever (DHF), although predominantly associated with secondary infections, has also been reported in primary infections. An enhanced immune response including antibodies and cytokines is implicated in the pathogenesis of secondary DHF. However, the factors operating in primary DHF are poorly understood. To understand the role of the antibody response, the relative levels of different antibody isotypes during the acute phase of infection in primary and secondary dengue infections were determined. Levels of DENV-specific IgM, IgG, IgA and IgE were measured in the serum samples of 200 dengue patients and 20 dengue-naïve individuals. Samples were collected within 15days of onset of illness. The DENV-specific IgM levels were significantly higher in DF cases compared to DHF, which was more evident in secondary infections and in post-defervescence samples. The levels of IgG, IgA and IgE were higher in DHF cases, with greater significance in primary infections. A higher level of IgG in DHF cases was evident in pre-defervescence samples, whilst the IgE level was higher in pre- and post-defervescence samples. There was a significant correlation of IgG titres with platelet counts, with higher titres associated with lower platelet counts. It is speculated that IgG, IgA and IgE produced in response to primary infections may contribute to pathogenesis, whilst IgM produced in response to secondary infections may protect against progression to severe disease.

Seroprevalence of Dengue infection in clinically suspected cases of dengue at tertiary care hospital in central India

Introduction: Dengue is one of the most serious mosquito borne viral infection of man affecting mainly tropical and subtropical countries and caused by four serotypes of dengue virus, namely DEN-1, DEN-2, DEN-3 and DEN-4 belonging to genus flavivirus and family flaviviridae. It spreads through the bite of infected Aedes mosquito. Dengue is potentially fatal viral infection that can culminate into dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The newer parameter NS1 antigen is detectable from day 1 of fever both in primary and secondary infections. Materials and Methods: Blood samples from clinically suspected cases of dengue tested immediately for qualitative detection of NS1 Ag, IgM and IgG antibodies by rapid solid phase immunochromatography test (ICT). Results: Out of 1090 samples tested, a total of 354 samples were tested positive for either one or more of the three markers i.e. NS1 Ag, IgM and IgG antibody tested. Of the 354 serum samples, 182 (51.41%) patients were positive for NS1 Ag only, 29 (8.19%) positive for IgM only, while 54 (15.25%) were positive for IgG only. More than one marker was detected in the remaining 89 (25.14%) samples. Primary dengue was detected in 224 (63.27%) cases and secondary dengue infection was detected in 130 (36.73%) cases. Conclusions: All suspected cases must be monitored for all three parameters i.e. NS1 Ag, IgM and IgG antibodies to differentiate between primary and secondary infection. Discrimination between primary and secondary dengue infections is important as the possibility of DHF and DSS is more in secondary infection.

Improving dengue viral antigens detection in dengue patient serum specimens using a low pH glycine buffer treatment.

Early diagnosis of dengue virus (DENV) infection to monitor the potential progression to hemorrhagic fever can influence the timely management of dengue-associated severe illness. Nonstructural protein 1 (NS1) antigen detection in acute serum specimens has been widely accepted as an early diagnostic assay for dengue infection; however, lower sensitivity of the NS1 antigen-capture enzyme-linked immunosorbent assay (Ag-ELISA) in secondary dengue viral infection has been reported. In this study, we developed two forms of Ag-ELISA capable of detecting E-Ag containing virion and virus-like particles, and secreted NS1 (sNS1) antigens, respectively. The temporal kinetics of viral RNA, sNS1, and E-Ag were evaluated based on the invitro infection experiment. Meanwhile, a panel of 62 DENV-2 infected patients' sera was tested. The sensitivity was 3.042ng/mL and 3.840ng/mL for sNS1 and E, respectively. The temporal kinetics of the appearance of viral RNA, E, NS1, and infectious virus in virus-infected tissue culture media suggested that viral RNAs and NS1 antigens could be detected earlier than E-Ag and infectious virus. Furthermore, a panel of 62 sera from patients infected by DENV Serotype 2 was tested. Treating clinical specimens with the dissociation buffer increased the detectable level of E from 13% to 92% and NS1 antigens from 40% to 85%. Inclusion of a low-pH glycine buffer treatment step in the commercially available Ag-ELISA is crucial for clinical diagnosis and E-containing viral particles could be a valuable target for acute DENV diagnosis, similar to NS1 detection.

NMR plasma metabolome discriminates subjects with dengue infection from non‐specific febrile infection

Brazil has a very high incidence of dengue. In 2013, approximately 1,500,000 cases of dengue infection, which presents no specific treatments,and over 200 deaths were reported. We aim to investigate plasma metabolome of subjects presenting symptoms of dengue fever (DF; mild), dengue hemorrhagic fever (DHF; severe), and subjects with non‐specific infection (NS). Samples were obtained in a cohort with dengue patients in Recife, Brazil. Plasma metabolomic analyzes were carried out by 1H Nuclear Magnetic Resonance. Using multivariate analysis, plasma metabolome from NS was discriminated from DF and DHF subjects. Additionally, DF plasma metabolome presenting secondary Dengue infection varies during the course infection. Candidate metabolites that contributed to the discriminatory pattern include β‐hydroxybutirate, citrate, succinate, tyrosine and valine. Discriminating NS from dengue infection through plasma NMR‐based metabolomics indicates that these analyzes could provide insights into the underlying molecular mechanisms of dengue pathogenesis. Moreover, following plasma metabolome during the course of dengue infection could help discriminating individuals at risk to develop severe infection and to predict the disease outcome.

The role of antibody in enhancing dengue virus infection

Dengue virus has four distinct serotypes whose cross-reactive immune responses contribute to increased disease severity following heterologous infections. It was proposed that non-protective cross-reactive antibodies may play a role in disease enhancement. In this study we develop a mathematical model of host–virus interaction and predict the mechanisms responsible for virus expansion and loss during primary and secondary dengue infections. We use the model to determine the role of cross-reactive antibodies during dengue fever and dengue hemorrhagic fever-inducing secondary infections, and then compare the model to published patient data. We predict that the cross-reactive antibodies interfere with the non-neutralizing antibody effects by reducing the phagocyte-mediated removal of antibody-virus immune complexes.

Minimal within-host dengue models highlight the specific roles of the immune response in primary and secondary dengue infections.

In recent years, the within-host viral dynamics of dengue infections have been increasingly characterized, and the relationship between aspects of these dynamics and the manifestation of severe disease has been increasingly probed. Despite this progress, there are few mathematical models of within-host dengue dynamics, and the ones that exist focus primarily on the general role of immune cells in the clearance of infected cells, while neglecting other components of the immune response in limiting viraemia. Here, by considering a suite of mathematical within-host dengue models of increasing complexity, we aim to isolate the critical components of the innate and the adaptive immune response that suffice in the reproduction of several well-characterized features of primary and secondary dengue infections. By building up from a simple target cell limited model, we show that only the innate immune response is needed to recover the characteristic features of a primary symptomatic dengue infection, while a higher rate of viral infectivity (indicative of antibody-dependent enhancement) and infected cell clearance by T cells are further needed to recover the characteristic features of a secondary dengue infection. We show that these minimal models can reproduce the increased risk of disease associated with secondary heterologous infections that arises as a result of a cytokine storm, and, further, that they are consistent with virological indicators that predict the onset of severe disease, such as the magnitude of peak viraemia, time to peak viral load, and viral clearance rate. Finally, we show that the effectiveness of these virological indicators to predict the onset of severe disease depends on the contribution of T cells in fuelling the cytokine storm.

Multicountry prospective clinical evaluation of two enzyme-linked immunosorbent assays and two rapid diagnostic tests for diagnosing dengue fever.

We evaluated four dengue diagnostic devices from Alere, including the SD Bioline Dengue Duo (nonstructural [NS] 1 Ag and IgG/IgM), the Panbio Dengue Duo Cassette (IgM/IgG) rapid diagnostic tests (RDTs), and the Panbio dengue IgM and IgG capture enzyme-linked immunosorbent assays (ELISAs) in a prospective, controlled, multicenter study in Peru, Venezuela, Cambodia, and the United States, using samples from 1,021 febrile individuals. Archived, well-characterized samples from an additional 135 febrile individuals from Thailand were also used. Reference testing was performed on all samples using an algorithm involving virus isolation, in-house IgM and IgG capture ELISAs, and plaque reduction neutralization tests (PRNT) to determine the infection status of the individual. The primary endpoints were the clinical sensitivities and specificities of these devices. The SD Bioline Dengue Duo had an overall sensitivity of 87.3% (95% confidence interval [CI], 84.1 to 90.2%) and specificity of 86.8% (95% CI, 83.9 to 89.3%) during the first 14 days post-symptom onset (p.s.o.). The Panbio Dengue Duo Cassette demonstrated a sensitivity of 92.1% (87.8 to 95.2%) and specificity of 62.2% (54.5 to 69.5%) during days 4 to 14 p.s.o. The Panbio IgM capture ELISA had a sensitivity of 87.6% (82.7 to 91.4%) and specificity of 88.1% (82.2 to 92.6%) during days 4 to 14 p.s.o. Finally, the Panbio IgG capture ELISA had a sensitivity of 69.6% (62.1 to 76.4%) and a specificity of 88.4% (82.6 to 92.8%) during days 4 to 14 p.s.o. for identification of secondary dengue infections. This multicountry prospective study resulted in reliable real-world performance data that will facilitate data-driven laboratory test choices for managing patient care during dengue outbreaks.

Atrial Fibrillation Due to Acute Myocarditis During Dengue Haemorrhagic Fever.

Atrial Fibrillation Due to Acute Myocarditis During Dengue Haemorrhagic Fever.

Naturally activated B-lymphocytes for dengue infection secrete CD27 and their plasma level is associated with severe forms of pediatric dengue

Naturally activated B-lymphocytes for dengue infection secrete CD27 and their plasma level is associated with severe forms of pediatric dengue

Dengue Antibody-Dependent Enhancement: Knowns and Unknowns.

Dengue provides the most abundant example in human medicine and the greatest human illness burden caused by the phenomenon of intrinsic antibody-dependent infection enhancement (iADE). In this immunopathological phenomenon infection of monocytes or macrophages using infectious immune complexes suppresses innate antiviral systems, permitting logarithmic intracellular growth of dengue virus. The four dengue viruses evolved from a common ancestor yet retain similar ecology and pathogenicity, but although infection with one virus provides short-term cross-protection against infection with a different type, millions of secondary dengue infections occur worldwide each year. When individuals are infected in the virtual absence of cross-protective dengue antibodies, the dengue vascular permeability syndrome (DVPS) may ensue. This occurs in around 2 to 4% of second heterotypic dengue infections. A complete understanding of the biologic mechanism of iADE, dengue biology, and the mechanism of host responses to dengue infection should lead to a comprehensive and complete understanding of the pathogenesis of DVPS. A crucial emphasis must be placed on understanding ADE. Clinical and epidemiological observations of DVPS define the research questions and provide research parameters. This article will review knowledge related to dengue ADE and point to areas where there has been little research progress. These observations relate to the two stages of dengue illnesses: afferent phenomena are those that promote the success of the microorganism to infect and survive; efferent phenomena are those mounted by the host to inhibit infection and replication and to eliminate the infectious agent and infected tissues. Data will be discussed as "knowns" and "unknowns."