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Kamaladasa A, Gomes L, Wijesinghe A, Jeewandara C, Toh YX, Jayathilaka D, Ogg GS, Fink K, Malavige GN. Altered monocyte response to the dengue virus in those with varying severity of past dengue infection. Antiviral Res 2019; 169:104554. [PMID: 31288040 DOI: 10.1016/j.antiviral.2019.104554] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 07/05/2019] [Accepted: 07/05/2019] [Indexed: 11/18/2022]
Abstract
OBJECTIVE We sought to investigate the differences in monocyte immune responses to the dengue virus (DENV) in those who previously had either severe disease (past SD) or non-severe dengue (past NSD) following a secondary dengue infection. METHOD Monocytes from healthy individuals who had either past SD (n = 6) or past NSD (n = 6) were infected at MOI one with all four DENV serotypes following incubation with autologous serum. 36-hours post infection, levels of inflammatory cytokines and viral loads were measured in the supernatant and expression of genes involved in viral sensing and interferon signaling was determined. RESULTS Monocytes of individuals with past SD produced significantly higher viral loads (p = 0.0426 and cytokines (IL-10 p = 0.008, IL-1β p = 0.008 and IL-6 p = 0.0411) when infected with DENV serotypes they were not immune to, compared to those who has past NSD. Monocytes of individuals with past SD also produced significantly higher viral loads (p = 0.022) and cytokines (IL-10 p < 0.0001, IL-1β < 0.0001 and IL-6 p < 0.0001) when infected with DENV serotypes they were previously exposed to, despite the monocytes being infected in the presence of autologous serum. A significant upregulation of NLRP3 (p = 0.005), RIG-I (0.0004) and IFNB-1 (0.01) genes were observed in those who had past SD compared to past NSD when infected with non-immune DENV serotypes. CONCLUSION Monocytes from those with past SD appear to show marked differences in viral loads, viral sensing and production of inflammatory mediators in response to the DENV, when compared to those who experienced past NSD, suggesting that initial innate immune responses may influence the disease outcome.
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Affiliation(s)
- Achala Kamaladasa
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka
| | - Laksiri Gomes
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka
| | - Ayesha Wijesinghe
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka
| | | | - Ying Xiu Toh
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Deshni Jayathilaka
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka
| | - Graham S Ogg
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka; MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, Oxford NIHR Biomedical Research Centre and University of Oxford, OX3 9DS, UK
| | - Katja Fink
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Singapore
| | - G N Malavige
- Centre for Dengue Research, University of Sri Jayawardanapura, Sri Lanka; MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, Oxford NIHR Biomedical Research Centre and University of Oxford, OX3 9DS, UK.
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Adikari TN, Gomes L, Wickramasinghe N, Salimi M, Wijesiriwardana N, Kamaladasa A, Shyamali NLA, Ogg GS, Malavige GN. Dengue NS1 antigen contributes to disease severity by inducing interleukin (IL)-10 by monocytes. Clin Exp Immunol 2016; 184:90-100. [PMID: 26621477 DOI: 10.1111/cei.12747] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 11/20/2015] [Accepted: 11/25/2015] [Indexed: 01/20/2023] Open
Abstract
Both dengue NS1 antigen and serum interleukin (IL)-10 levels have been shown to associate with severe clinical disease in acute dengue infection, and IL-10 has also been shown to suppress dengue-specific T cell responses. Therefore, we proceeded to investigate the mechanisms by which dengue NS1 contributes to disease pathogenesis and if it is associated with altered IL-10 production. Serum IL-10 and dengue NS1 antigen levels were assessed serially in 36 adult Sri Lankan individuals with acute dengue infection. We found that the serum IL-10 levels correlated positively with dengue NS1 antigen levels (Spearman's r = 0·47, P < 0·0001), and NS1 also correlated with annexin V expression by T cells in acute dengue (Spearman's r = 0·63, P = 0·001). However, NS1 levels did not associate with the functionality of T cell responses or with expression of co-stimulatory molecules. Therefore, we further assessed the effect of dengue NS1 on monocytes and T cells by co-culturing primary monocytes and peripheral blood mononuclear cells (PBMC), with varying concentrations of NS1 for up to 96 h. Monocytes co-cultured with NS1 produced high levels of IL-10, with the highest levels seen at 24 h, and then declined gradually. Therefore, our data show that dengue NS1 appears to contribute to pathogenesis of dengue infection by inducing IL-10 production by monocytes.
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Affiliation(s)
- T N Adikari
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - L Gomes
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - N Wickramasinghe
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - M Salimi
- Radcliffe Department of Medicine, MRC Human Immunology Unit, NIHR Biomedical Research Centre, Weatherall Institute of Molecular Medicine, Oxford, UK
| | - N Wijesiriwardana
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - A Kamaladasa
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - N L A Shyamali
- Department of Medicine, Faculty of Medical Sciences, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
| | - G S Ogg
- Radcliffe Department of Medicine, MRC Human Immunology Unit, NIHR Biomedical Research Centre, Weatherall Institute of Molecular Medicine, Oxford, UK
| | - G N Malavige
- Centre for Dengue Research, University of Sri Jayawardanapura, Nugegoda, Sri Lanka.,Radcliffe Department of Medicine, MRC Human Immunology Unit, NIHR Biomedical Research Centre, Weatherall Institute of Molecular Medicine, Oxford, UK
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Crack LR, Jones L, Malavige GN, Patel V, Ogg GS. Human antimicrobial peptides LL-37 and human β-defensin-2 reduce viral replication in keratinocytes infected with varicella zoster virus. Clin Exp Dermatol 2012; 37:534-43. [PMID: 22639919 DOI: 10.1111/j.1365-2230.2012.04305.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND There is mounting evidence that antimicrobial peptides have an important role in cutaneous defence, but the expression of these antimicrobial peptides in atopic eczema (AE) is still unclear. There are several families of antimicrobial peptides, including cathelicidins and human β-defensins. Patients with AE are more susceptible to severe cutaneous viral infections, including varicella zoster virus (VZV). AIM To characterize the functional activity of the antimicrobial peptides LL-37 (human cathelicidin) and human β-defensin (hBD)-2 keratinocytes were infected with VZV, in a skin-infection model. METHODS Flow-cytometry analysis was used to investigate LL-37 expression in normal human keratinocytes, and quantitative PCR was used to determine viral loads in infected HaCaT keratinocytes and B cells, with and without exogenous LL-37 and hBD-2. RESULTS LL-37 expression was present in keratinocytes, and both exogenous LL-37 and hBD-2 significantly reduced VZV load in infected keratinocytes and B cells. Specific antibodies blocked the antiviral action exhibited by these antimicrobial peptides. Pre-incubation of VZV with LL-37, but not hBD-2, further reduced VZV load. CONCLUSIONS Both LL-37 and hBD-2 have an antiviral effect on VZV replication in the keratinocyte HaCaT cell line and in B cells, but their mechanism of action is different. Evidence of the relationship between antimicrobial peptide expression and higher susceptibility to infections in AE skin is still emerging. Developing novel antiviral therapies based on antimicrobial peptides may provide improved treatment options for patients with AE.
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Affiliation(s)
- L R Crack
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford and NIHR Research Centre, Oxford, Oxfordshire, UK
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Malavige GN, McGowan S, Atukorale V, Salimi M, Peelawatta M, Fernando N, Jayaratne SD, Ogg G. Identification of serotype-specific T cell responses to highly conserved regions of the dengue viruses. Clin Exp Immunol 2012; 168:215-23. [PMID: 22471283 DOI: 10.1111/j.1365-2249.2012.04566.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Determining previous infecting dengue virus (DENV) serotypes has been difficult due to highly cross-reactive immune responses from previous DENV infections. Determining the correlates of serotype-specific immune responses would be crucial in understanding dengue transmission in the community and would also help to determine the correlates of protective immune responses. Therefore, we set out to define highly conserved, serotype-specific regions of the DENVs. Serotype-specific and highly conserved regions of the four DENV serotypes were identified using Basic Local Alignment Search Tool (BLAST) searches and custom perl scripts. Using ex-vivo and cultured enzyme-linked immunospot (ELISPOT) assays, we identified serotype-specific T cell epitopes within the four DENV serotypes in healthy adult donors from Sri Lanka. We identified T cell responses to 19 regions of the four DENV serotypes. Six peptides were from the NS2A region and four peptides were from the NS4A region. All immune donors responded to peptides of at least two DENV serotypes, suggesting that heterologous infection is common in Sri Lanka. Eight of 20 individuals responded to at least two peptides of DENV-4, despite this serotype not being implicated previously in any of the epidemics in Sri Lanka. The use of these regions to determine past and current infecting DENV serotypes will be of value to characterize further the dynamics of silent dengue transmission in the community. In addition, these T cell responses to these regions could be used to characterize DENV serotype-specific immune responses and thus possibly help us to understand the immune correlates of a protective immune response.
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Affiliation(s)
- G N Malavige
- Department of Microbiology, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
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Gomes PLR, Malavige GN, Fernando N, Mahendra MHR, Kamaladasa SD, Seneviratne JKK, Karunatilaka DH, Ogg GS. Characteristics of Staphylococcus aureus colonization in patients with atopic dermatitis in Sri Lanka. Clin Exp Dermatol 2010; 36:195-200. [PMID: 21070340 DOI: 10.1111/j.1365-2230.2010.03962.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Colonization of the skin of patients with atopic dermatitis (AD) by Staphylococcus aureus (SA) is associated with more severe disease. AIM To determine the association of SA colonization patterns and densities in lesional and nonlesional skin in patients with varying severities of AD, and to determine the antibiotic sensitivity patterns of SA isolates from Sri Lanka. METHODS Skin and nasal swabs collected from 100 patients with AD and 120 controls were used to investigate the presence of SA. Severity of AD was graded using the Nottingham Eczema Severity Score. Colony counts were obtained for skin samples, and antibiotic sensitivity testing was performed in cases positive for SA. RESULTS Skin colonization was seen in 57 patients (57%) but in only 10 controls (8%). Lesional skin of most patients (52/57; 91%) had SA densities of > 300 colony-forming units/cm(2) . Colonization rates with SA significantly increased with increasing age (Spearman correlation coefficient R = 0.9, P < 0.05) and increasing duration of lesions in patients with AD (Spearman R = 0.87, P < 0.05). Isolates from eight patients (13.5%) were found to be methicillin-resistant S. aureus (MRSA). Only 6 isolates (10%) were susceptible to penicillin and 22 (37%) to erythromycin, while 28 (47%) isolates had erythromycin-induced resistance to clindamycin. CONCLUSIONS SA colonization rates were significantly associated with increasing age and severity of AD, and particularly with duration of lesions. Patients with severe disease were also more likely to be colonized with SA strains resistant to conventional antibiotics.
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Affiliation(s)
- P L R Gomes
- Department of Microbiology, University of Sri Jayawardanapura, Sri Lanka
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Malavige GN, Rohanachandra LT, Jones L, Crack L, Perera M, Fernando N, Guruge D, Ogg GS. IE63-specific T-cell responses associate with control of subclinical varicella zoster virus reactivation in individuals with malignancies. Br J Cancer 2010; 102:727-30. [PMID: 20087346 PMCID: PMC2837573 DOI: 10.1038/sj.bjc.6605542] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background: Reactivation of the varicella zoster virus (VZV) is more common in patients with malignancies; however, the molecular and cellular mechanisms underlying this susceptibility are unclear. Methods: Using ex vivo interferon-γ ELISpot assays, we set out to analyse VZV-specific immune responses in a large cohort of patients with malignancies. Results: We observed that patients with malignancies had impaired VZV-specific T-cell responses, particularly in those with haematological malignancies and breast carcinoma. Immediate-early protein 63 (IE63)-specific T-cell responses were significantly impaired in those with subclinical VZV re-activation. Conclusions: Our results suggest that T-cell responses to IE63 are important in controlling VZV replication.
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Affiliation(s)
- G N Malavige
- Department of Microbiology, University of Sri Jayawardanapura, Nugegoda, Sri Lanka
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Malavige GN, Jones L, Black AP, Ogg GS. Varicella zoster virus glycoprotein E-specific CD4+ T cells show evidence of recent activation and effector differentiation, consistent with frequent exposure to replicative cycle antigens in healthy immune donors. Clin Exp Immunol 2008; 152:522-31. [PMID: 18363743 DOI: 10.1111/j.1365-2249.2008.03633.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Varicella zoster viru (VZV)-specific T cell responses are believed to be vital in recovery from primary VZV infection and also in the prevention of viral reactivation. While glycoprotein E (gE) is the most abundant and one of the most immunogenic proteins of the virus, there are no data addressing potential T cell epitopes within gE, nor the phenotype of specific T cells. Using interferon gamma enzyme-linked immunospot assays and intracellular cytokine assays, we identified gE-specific immune responses in 20 adult healthy immune donors which were found to be dominated by the CD4+ subset of T cells. We characterized three immune dominant epitopes within gE restricted through DRB1*1501, DRB1*07 and DRB4*01, and used DRB1*1501 class II tetrameric complexes to determine the ex vivo frequency and phenotype of specific T cells. In healthy immune donors, the cells were largely positive for CCR7, CD28 and CD27, but expressed variable CD62L and low levels of cutaneous lymphocyte associated antigen with evidence of recent activation. In summary, we show that circulating gE-specific CD4+ T cells are detected at a relatively high frequency in healthy immune donors and show evidence of recent activation and mixed central and effector memory phenotype. These data would be compatible with frequent exposure to replicative cycle antigens in healthy donors and are consistent with a role for gE-specific CD4+ T cells in the control of viral replication.
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Affiliation(s)
- G N Malavige
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
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Karunatilaka DH, De Silva JRS, Ranatunga PK, Gunasekara TM, Faizal MA, Malavige GN. Idiopathic purpura fulminans in dengue hemorrhagic fever. ACTA ACUST UNITED AC 2008. [PMID: 17679737 DOI: 10.4103/0019-5359.33712] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Purpura fulminans is a rapidly progressive thrombotic disease that has been described during both severe bacterial and viral infections. Disseminated intravascular coagulation (DIC), antiphospholipid antibodies and acquired or congenital C and S protein deficiency are thought to play a role in its pathogenesis. Here we report the case of a 4-year-old girl who developed gangrene of all her fingers and toes following dengue shock syndrome complicated by DIC and also discuss its management.
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Malavige GN, Rostron T, Seneviratne SL, Fernando S, Sivayogan S, Wijewickrama A, Ogg GS. HLA analysis of Sri Lankan Sinhalese predicts North Indian origin. Int J Immunogenet 2007; 34:313-5. [PMID: 17845299 DOI: 10.1111/j.1744-313x.2007.00698.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The origin of the Sinhalese population of Sri Lanka is debated. We subtyped HLA-A*02 in 101 Sinhalese and observed a preponderance of the rare allele HLA-A*0211 which was similar to reported frequencies in northern India. Taken with low-resolution typing for the remaining A, B, C, DR and DQ alleles, these data suggest a North Indian origin for the Sri Lankan Sinhalese.
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Affiliation(s)
- G N Malavige
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
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Malavige GN, Ranatunga PK, Jayaratne SD, Wijesiriwardana B, Seneviratne SL, Karunatilaka DH. Dengue viral infections as a cause of encephalopathy. Indian J Med Microbiol 2007; 25:143-5. [PMID: 17582186 DOI: 10.4103/0255-0857.32722] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The aim of this study was to determine the clinical characteristics and poor prognostic factors associated with high mortality in dengue encephalopathy. Fifteen patients with confirmed dengue infections, who developed encephalopathy, were recruited from two tertiary care hospitals in Colombo, Sri Lanka. Among the factors that contributed to encephalopathy were: Acute liver failure (73%), electrolyte imbalances (80%) and shock (40%). Five (33.3%) patients developed seizures. Disseminated intravascular coagulation was seen in five (33.3%). Secondary bacterial infections were observed in 8 (53.3%) of our patients. The overall mortality rate was 47%.
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Affiliation(s)
- G N Malavige
- Department of Microbiology, University of Jayawardenapura, Colombo, Sri Lanka.
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Karunatilaka DH, De Silva JRS, Ranatunga PK, Gunasekara TM, Faizal MA, Malavige GN. Idiopathic purpura fulminans in dengue hemorrhagic fever. Indian J Med Sci 2007; 61:471-3. [PMID: 17679737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Purpura fulminans is a rapidly progressive thrombotic disease that has been described during both severe bacterial and viral infections. Disseminated intravascular coagulation (DIC), antiphospholipid antibodies and acquired or congenital C and S protein deficiency are thought to play a role in its pathogenesis. Here we report the case of a 4-year-old girl who developed gangrene of all her fingers and toes following dengue shock syndrome complicated by DIC and also discuss its management.
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Liyanage NPM, Fernando S, Malavige GN, Mallikahewa R, Sivayogan S, Jiffry MTM, Vitarana T. Seroprevalence of varicella zoster virus infections in Colombo district, Sri Lanka. ACTA ACUST UNITED AC 2007. [PMID: 17337813 DOI: 10.4103/0019-5359.30747] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Although Varicella Zoster virus (VZV) infections occur worldwide, the epidemiology is remarkably different in tropical and temperate climates. VZV infections result in significant morbidity and mortality among adults in Sri Lanka. AIMS For future VZV vaccination strategies, we set to determine the age-specific seroprevalence rate of VZV infections in Colombo, Sri Lanka. MATERIALS AND METHODS The study was carried out from 1999 to 2000. Multi-stage cluster sampling technique was used to collect 913 blood samples, which were tested for the presence of VZV-specific IgG antibodies. RESULTS VZV seroprevalence rates were markedly lower in all age groups when compared to temperate climates. The seroprevalence rates increased with age in both the rural and urban populations. Of those aged 60 years, only 50% in the rural population and 78.9% in the urban population were immune to VZV. Seroprevalence rates of VZV infections were significantly different between the urban and rural populations (P< 0.001), with VZV-specific IgG antibodies detected in 47.5% in the urban population and 27.9% in the rural population. It was found that 56.2% (131) of females of childbearing age were nonimmune to VZV. CONCLUSIONS These findings highlight the need for a VZV vaccination program, which is likely to have a huge impact on the incidence of chickenpox and its associated morbidity and mortality.
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Affiliation(s)
- N P M Liyanage
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayawardanapura, Sri Lanka
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Malavige GN, Ranatunga PK, Jayaratne SD, Wijesiriwardana B, Seneviratne SL, Karunatilaka DH. DENGUE VIRAL INFECTIONS AS A CAUSE OF ENCEPHALOPATHY. Indian J Med Microbiol 2007. [DOI: 10.1016/s0255-0857(21)02174-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Liyanage NPM, Fernando S, Malavige GN, Mallikahewa R, Sivayogan S, Jiffry MTM, Vitarana T. Seroprevalence of varicella zoster virus infections in Colombo district, Sri Lanka. Indian J Med Sci 2007; 61:128-34. [PMID: 17337813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND Although Varicella Zoster virus (VZV) infections occur worldwide, the epidemiology is remarkably different in tropical and temperate climates. VZV infections result in significant morbidity and mortality among adults in Sri Lanka. AIMS For future VZV vaccination strategies, we set to determine the age-specific seroprevalence rate of VZV infections in Colombo, Sri Lanka. MATERIALS AND METHODS The study was carried out from 1999 to 2000. Multi-stage cluster sampling technique was used to collect 913 blood samples, which were tested for the presence of VZV-specific IgG antibodies. RESULTS VZV seroprevalence rates were markedly lower in all age groups when compared to temperate climates. The seroprevalence rates increased with age in both the rural and urban populations. Of those aged 60 years, only 50% in the rural population and 78.9% in the urban population were immune to VZV. Seroprevalence rates of VZV infections were significantly different between the urban and rural populations (P< 0.001), with VZV-specific IgG antibodies detected in 47.5% in the urban population and 27.9% in the rural population. It was found that 56.2% (131) of females of childbearing age were nonimmune to VZV. CONCLUSIONS These findings highlight the need for a VZV vaccination program, which is likely to have a huge impact on the incidence of chickenpox and its associated morbidity and mortality.
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Affiliation(s)
- N P M Liyanage
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayawardanapura, Sri Lanka
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Malavige GN, Weerasooriya N, de Alwis NMW, Fernando DJS. The validity of fasting blood glucose and post-prandial blood glucose measurement as an index of glycaemic control in Sri Lankan patients with type 2 diabetes. ACTA ACUST UNITED AC 2006; 51:40-1. [PMID: 16898040 DOI: 10.4038/cmj.v51i1.1380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Waduge R, Malavige GN, Pradeepan M, Wijeyaratne CN, Fernando S, Seneviratne SL. Dengue infections during pregnancy: A case series from Sri Lanka and review of the literature. J Clin Virol 2006; 37:27-33. [PMID: 16843056 DOI: 10.1016/j.jcv.2006.06.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 05/14/2006] [Accepted: 06/07/2006] [Indexed: 11/18/2022]
Abstract
BACKGROUND Dengue is a major public health problem in several countries. Few reports document presentations and outcomes of dengue during pregnancy. In many endemic countries as the average age of getting dengue infections is shifting upwards, dengue in pregnancy is likely to be encountered more frequently. Patterns of dengue in patients from different regions are needed if we are to draft evidence based management guidelines. OBJECTIVES To document clinical and laboratory findings in a cohort of hospitalised patients with dengue during pregnancy in Sri Lanka and compare their presentation and outcomes with previously published cases. STUDY DESIGN Clinical, laboratory, maternal and fetal outcomes and demographic information were collected from patients with confirmed dengue infections during pregnancy treated in a Maternity Hospital in Sri Lanka from 1 January 2000 to 30 June 2004. The Medline database was searched to identify reports relating to dengue infection during pregnancy since 1965. RESULTS Twenty-six patients [mean (S.D.) age: 29 (4.2) years] were studied. One (3.8%), 2 (7.7%) and 20 (77%) presented in the first, second and third trimesters of pregnancy, and 3 (11.5%) in the immediate post-partum period. Seventeen (65.3%) had primary and nine (34.7%) secondary dengue infections. Ten (38.5%) had DF, 6 (23.1%): DHF grade I and 10 (38.5%): DHF grade II. Five (19.2%) and three (11.5%) patients who first presented with cough/breathlessness or vaginal bleeding, were initially managed as having a pulmonary embolism or a primary obstetric cause for their vaginal bleeding. Bradycardia was noted in three of the four patients who had a cardiac arrhythmia. Seven (26.9%) needed admission to an ICU. Raised AST and ALT levels were seen in 81.2% and 43.7% of 16 patients in whom liver function tests results were available. No fetal malformations were seen in any of the babies born. The single patient who developed DHF in the first trimester had an abortion while having acute symptoms of dengue. CONCLUSIONS Awareness of clinical and laboratory manifestations of dengue in pregnancy should allow its early recognition and institution of appropriate treatment. Reports on dengue in pregnancy from different regions should allow more evidence-based guidelines to be formulated for optimum evaluation and care of such patients. Our data contributes towards this goal.
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Affiliation(s)
- Ranmali Waduge
- Department of Obstetrics & Gynaecology, Faculty of Medicine, University of Colombo, Sri Lanka
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Malavige GN, Velathanthiri VGNS, Wijewickrama ES, Fernando S, Jayaratne SD, Aaskov J, Seneviratne SL. Patterns of disease among adults hospitalized with dengue infections. QJM 2006; 99:299-305. [PMID: 16603571 DOI: 10.1093/qjmed/hcl039] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Recent years have seen an increase in dengue infections among adults in Sri Lanka, with similar trends seen in many other countries. Data on the natural history and outcome of dengue in adults are quite limited. AIM To study clinical and laboratory findings in adult dengue patients hospitalized in Sri Lanka during a recent major dengue epidemic. DESIGN Prospective observational study. METHODS Clinical, laboratory and demographic information were collected from adult patients with confirmed dengue infections (n = 108) treated in a general medical ward in Sri Lanka from 24 April to 31 July 2004. RESULTS There were 68 male and 40 female patients, mean age 26.6 years. Dengue fever (DF) was seen in 33 (30.6%) and dengue haemorrhagic fever (DHF) in 75 (69.4%). Of the 37 (34.3%) with primary dengue infections, 19 (51.4%) developed DF and 18 (48.6%) developed DHF. Overall, 42 patients (38.9%) had bleeding manifestations. These adults showed differences in clinical and laboratory findings, disease severity and mortality, compared to children seen during the same epidemic. Secondary dengue infections were significantly associated with development of severe disease (OR 5.0, 95%CI 1.9-13.5, p < 0.001). Mortality was 3.7%. DISCUSSION Pooling data on adult dengue patients from different regions should help us to understand the natural history of disease in this group. It would also help in developing evidence-based treatment guidelines and allocating limited and scarce health resources. Our data contribute towards this goal.
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Affiliation(s)
- G N Malavige
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayawardanapura, Sri Lanka
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Abstract
BACKGROUND Dengue is the most important mosquito borne viral infection in the world. Nearly 90% of infections occur in children. At present, prospective information on clinical and laboratory findings in South Asian children with dengue is generally lacking. AIM To describe patterns of clinical disease in a cohort of children hospitalised with dengue during a major dengue epidemic in Sri Lanka. RESULTS A total of 104 children were studied during a three month period. Eighteen had dengue fever (DF) and 86 had dengue haemorrhagic fever (DHF). Of those with DHF, 34, 23, 27, and 2 had DHF grade I, II, III, and IV respectively. Based on dengue serology testing, 13 of the DF patients had a primary infection and 5 had secondary dengue infections. In contrast, 68 of the children with DHF had secondary and 18 had primary dengue infections. Oral candidiasis was seen in 19 children. The odds ratio for children with secondary dengue infection to develop DHF was 9.8 (95% CI 3.1 to 31.2). CONCLUSION Studies on patterns of paediatric dengue disease in different regions should help clinicians and health administrators make more informed and evidence based health planning decisions. It should also help towards mapping out dengue trends on a global scale. Oral candidiasis has not been previously documented in children suffering with acute dengue in Sri Lanka or elsewhere. Studying underlying reasons for this manifestation during future dengue epidemics may provide useful leads in understanding overall dengue pathogenesis.
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Affiliation(s)
- G N Malavige
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayawardenapura, Sri Lanka
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Seneviratne SL, Malavige GN, de Silva HJ. Pathogenesis of liver involvement during dengue viral infections. Trans R Soc Trop Med Hyg 2006; 100:608-14. [PMID: 16483623 DOI: 10.1016/j.trstmh.2005.10.007] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Revised: 10/21/2005] [Accepted: 10/21/2005] [Indexed: 12/31/2022] Open
Abstract
The dengue virus can infect many cell types and cause diverse clinical and pathological effects. We describe clinical and experimental observations that suggest that liver involvement occurs during dengue infections, and we outline the possible role played by host immune responses in this process.
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Affiliation(s)
- S L Seneviratne
- Department of Clinical Immunology, Level 7, John Radcliffe Hospital, Oxford OX3 9DU, UK.
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Abstract
Dengue viral infections are one of the most important mosquito borne diseases in the world. They may be asymptomatic or may give rise to undifferentiated fever, dengue fever, dengue haemorrhagic fever (DHF), or dengue shock syndrome. Annually, 100 million cases of dengue fever and half a million cases of DHF occur worldwide. Ninety percent of DHF subjects are children less than 15 years of age. At present, dengue is endemic in 112 countries in the world. No vaccine is available for preventing this disease. Early recognition and prompt initiation of appropriate treatment are vital if disease related morbidity and mortality are to be limited. This review outlines aspects of the epidemiology of dengue infections, the dengue virus and its mosquito vector, clinical features and pathogenesis of dengue infections, and the management and control of these infections.
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Affiliation(s)
- G N Malavige
- Department of Clinical Immunology, A Floor, West Block, Queens Medical Centre, University Hospital, Nottingham NG7 2UH, UK
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Affiliation(s)
- G N Malavige
- Faculty of Medical Sciences, University of Sri Jayawardanapura, Sri Lanka.
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Affiliation(s)
- G N Malavige
- University of Sri Jayawardanapura, Department of Microbiology, Faculty of Medical Sciences, Gangodawila Nugegoda, Sri Lanka;
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Malavige GN. Chronic cough. . . .and tropical pulmonary eosinophilia. BMJ 2003; 326:1036. [PMID: 12749330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
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Malavige GN, de Alwis NMW, Weerasooriya N, Fernando DJS, Siribaddana SH. Increasing diabetes and vascular risk factors in a sub-urban Sri Lankan population. Diabetes Res Clin Pract 2002; 57:143-5. [PMID: 12062860 DOI: 10.1016/s0168-8227(02)00015-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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