Chandima Jeewandara

Background: During the 2024–2025 Chikungunya virus (CHIKV) resurgence in Sri Lanka, atypical neurological manifestations (neuro-CHIKV) emerged. We aimed to define the clinical, diagnostic, and longitudinal profiles of these patients. Methods: This descriptive case series at National Hospital Galle (April–September 2025) evaluated 11 adults (median age 59; five >60 years) presenting with neurological symptoms and serologically confirmed CHIKV infection. Results: Central nervous system (CNS) involvement predominated (n=9). Acute presentations (≤7 days) included encephalitis (n=4) and meningoencephalitis (n=1) and delayed presentations (≥7 days) featured late-onset encephalitis (n=3), acute disseminated encephalomyelitis (n=1), and peripheral syndromes (Guillain-Barré variant, Bell's palsy). Reduced consciousness affected 7 out of 9 CNS cases, occasionally compounded by acute kidney/liver injury or profound hyponatremia. Diagnostically, 30% exhibited atypical cerebrospinal fluid profiles (hypoglycorrhachia or hyperproteinorrhachia without pleocytosis) mimicking bacterial meningitis. Neuroimaging revealed variety of radiological findings such as non-haemorrhagic acute necrotizing encephalopathy, a spinal cord "H-sign" and isolated bilateral caudate/putamina hyperintensities. Early systemic corticosteroids (≤7 days, n=4) correlated with favourable functional recovery, whereas delayed initiation yielded negligible responses in 2 out of 3 patients. Overall mortality was 18.2% (n=2), and 62.5% of survivors exhibited persistent non-severe neurological or rheumatological sequelae at three months. Conclusion: Neuro-CHIKV poses a high-mortality diagnostic challenge due to atypical clinical, biochemical and neuroradiological presentations. Early immunomodulation with therapeutic options such as steroids was associated with favourable neurological recovery and warrants prospective evaluation.

Severe dengue can damage the liver through unestablished mechanisms. We investigated the role of myeloperoxidase (MPO), a neutrophil enzyme, in dengue through patients, fatal liver samples, and mouse infection models. Observations from two independent clinical cohorts revealed elevated plasma MPO levels in dengue and, in one cohort, MPO was further linked to liver injury markers during the critical phase of disease, whereas livers from dengue fatal cases revealed MPO build-up in the vicinity of CD177+ activated neutrophils. In mice, dengue led to MPO overexpression, oxidative damage, and broad activation of innate and systemic inflammatory pathways in livers. Blocking MPO activity alleviated these and improved survival in one model and delayed disease progression without preventing death in another. These findings establish MPO as a functional mediator of severe dengue-associated liver injury and inflammation, which warrants further preclinical investigation into its hepatic pathogenic mechanism and its validity as target for therapeutic intervention.

Background: Determining serotype-specific age stratified dengue (DENV) and Zika (ZIKV) seroprevalence rates is crucial for implementing vaccines and vector control strategies. Therefore, we sought to assess age-stratified seroprevalence of monotypic or multi-typic exposure in a community cohort in Sri Lanka. Methods: The DENV-specific serostatus was assessed in 4,161 children aged 4 to 16 years, using an in-house DENV specific IgG ELISA and compared the results with a widely used commercial assay (dengue indirect Panbio IgG ELISA). We also used a multiplexed, microsphere-based serological assay, to characterise monotypic vs multi-typic responses and to differentiate exposure rates to different DENV serotypes and ZIKV in a sub-cohort of children (n=604). Results: By IgG-ELISA DENV seropositivity was 72.34% (n=4,161), and the seropositivity rate significantly increased with age (Spearman’s r=1.0, p=0.003). The estimated FOI was 0.16 (95% credible interval 0.14–0.17). Of the 604 individuals tested by Luminex, 258 (42.7%) had a monotypic dengue response, whereas 209 (34.9%) had a multi-typic response. 100 (16.5%) had evidence of a past infection to Zika, while 20 (3.33%) children, only had antibodies to the ZIKV. Of the 258 individuals with evidence of a monotypic response to DENV, DENV2 (56.83%) and DENV1 (30.57%) accounted for most infections. An inverse correlation between exposure to ZIKV and age (Spearmans’s r=-0.72, 0=0.007). Discussion: 72.3% of children were seropositive for dengue with 42.7% been infected with only one DENV in the past. The data suggests that prior immunity to DENV may reduce the risk of ZIKV infection, which should be further assessed.

Currently, the role of dengue virus-specific T-cell responses in disease pathogenesis and protection is not well understood, including potential differences in individuals with obesity. We sought to investigate the functionality and phenotype of T cells in patients with acute dengue fever (DF) or dengue haemorrhagic fever (DHF). T-cell function was assessed in paired samples (first sample on ≤4 days and second 5–6 days since onset of illness) in patients with DF (n = 50) and DHF (n = 12), using 109 peptides representing CD8+ epitopes and 90 peptides targeting CD4+ T-cell epitopes. Phenotypic analysis was performed in patients with DF (n = 21) and DHF (n = 21), recruited between days 6 and 8 since onset of illness, using multicolor flow cytometry. The frequency of ex vivo IFNγ ELISpot responses to both the CD4+ and CD8+ peptide pools significantly increased from first (F) to second (S) time point in patients with DF (P < 0.0001) but not with DHF. The frequency of ex vivo IFNγ ELISpot responses to CD4+ (P = 0.001) and CD8+ peptide pools (P = 0.0002) also significantly increased from the F to S in lean patients but not in obese patients. Cutaneous lymphocyte-associated antigen (CLA) expression was significantly higher in the CD8+ T-cell subset in patients with DF and DHF compared to healthy controls, and these differences were most significant in CD8+ CD45RA− T cells. CD8+ CD45RA−CLA+ T cells consisted of >50% of the T cells in 9/21 patients with DHF, with 92.7% expressing CD38. CLA expression was highest in the CD8+ CD45RA− T cells in obese individuals, which was significantly higher compared to lean individuals (P = 0.01). CD27 and CD127 were both significantly downregulated in patients with DHF compared to DF, with ICOS expression being significantly higher in CD8+ T cells in DHF. Patients with DHF and obese individuals had impaired T-cell functionality compared to patients with DF and lean individuals, with an expansion of activated, skin-homing CD8+ T cells exhibiting downregulation of CD27 and CD127. Our data suggest a contributory role of dysfunctional skin-homing T cells in disease pathogenesis, meriting further investigation.

Methamphetamine is a highly addictive stimulant with severe health and psychosocial consequences. Over recent decades, genetic and molecular research on methamphetamine use disorders has expanded considerably, yet a comprehensive synthesis of this growing body of literature is lacking. This study conducted a bibliometric analysis to map the scientific landscape of genetic and molecular biology research on methamphetamine use, identifying key contributors, influential publications, publication trends, and co-occurring keywords and citations. A systematic search of the Scopus database retrieved 1550 documents. After applying the inclusion criteria and manual screening, 449 peer-reviewed articles published between 1993 and 2025 were included. Performance analysis and scientific mapping were conducted using VOSviewer software through bibliographic coupling and keyword co-occurrence. The study followed the BIBLIO checklist for reporting bibliometric reviews in biomedical literature. Publication output increased markedly after 2005, peaking in 2022, followed by a decline that may reflect a shift in research priorities. The United States, China, and Japan emerged as leading contributors, underscoring their significant investment in addiction and molecular research. Keyword co-occurrence revealed strong emphasis on addiction, dopamine, neurotoxicity, gene expression, and genetic polymorphisms, highlighting their central role in the pathophysiology of methamphetamine use disorders. This bibliometric analysis demonstrates substantial growth and influence of genetic research on methamphetamine use. Despite a recent decline in publications, the field provides a solid foundation for future interdisciplinary research and funding priorities in addiction genetics.

Background: Cardiovascular diseases (CVD) are the leading cause of death in South Asia with visceral adiposity and sarcopenic obesity emerging as critical risk factors. Methods: We conducted a cross-sectional study in 139 Sri Lankan adults (mean age 39.3, SD ± 10.7, 52 females and 87 males) to assess visceral adipose tissue (VAT) area, fat mass index (FMI), fat mass ratio (FMR) and lean muscle mass, expressed as the appendicular lean mass index (ALMI) using dual energy Xray absorptiometry (DEXA). Fasting blood sugar (FBS, lipid profiles, apolipoproteins (A1 and B) and inflammatory markers (IL-6 and IL-1b) were analysed. Results: 23 (44%) females and 67 (77%) of males had a VAT area of ≥ 100cm ² , 34 (65%) females and 79 (91%) males had an FMI of above the cut-off value and 30 (58%) females, and 33 (38%) males had an FMR above the cut-off value. Females with high VAT area (≥100cm ² ) had significantly higher levels of FBS (p=0.008) and lower HDL and Apo A1 (p2 . Further, females with an FMI of ≥9 had significantly higher FBS levels (p=0.01), and those with a FMR of ≥ of 1.2 were had significantly higher FBS and ApoB levels with significantly lower ApoA1 levels. There were no differences in metabolic risk factors or inflammatory mediators in males with an FMI above the cut-off value (≥6) or with a high FMR. 34 (65%) females had a low ALMI below (<5.5), while 47 (54%) males had a low ALMI (<7). ApoB levels, ApoB/ApoA1 ratio and serum cholesterol were significantly higher in males with a ALMI <7, than those with normal ALMI. Conclusion: Visceral adiposity and a low lean muscle mass appear to be prevalent in South Asians with gender specific metabolic implications. Given the marked rise in CVD, diabetes and obesity related diseases in South Asia, urgent measures should be adopted to reduce the burden of illness due to these illnesses and diseases associated with frailty.

Introduction Colorectal cancer (CRC) is the third most common and second most deadly cancer worldwide, with significant morbidity and mortality risks. Despite advancements in surgical care, postoperative complications and recovery challenges persist. The severity of these issues is linked to preoperative functional capacity and emotional distress. Mindfulness, known for enhancing emotional well-being, is being considered as a promising intervention in cancer care. This study investigates the effectiveness of mindfulness-based tri-modal prehabilitation in improving functional recovery and surgical outcomes for patients with CRC. Methods and analysis The sample size of this prospective, randomised controlled trial was calculated based on the primary outcome, which is the detection of the clinically significant difference in a 6 min walk test (6MWT). With our population variables, the size of the sample was estimated for an α level of 0·05 (two-sided) and 80% power to detect a clinically meaningful difference between groups at postsurgical follow-up of 32 m, with an estimated variability of 64 m based on previous studies. The final sample size is 72 patients, in both arms. Both groups will receive a 4-week standard tri-modal prehabilitation. The intervention group will receive a mindfulness practice module. Outcomes will be measured at four different time intervals for each patient. Secondary outcome measures cover nutritional status, psychological status and selected biomarker status. Patient recruitment to the study started in April 2022. Ethics and dissemination This study was approved by the Ethics Review Committee of the Faculty of the Medical Sciences University of Sri Jayewardenepura (Registration No: FMC/ USJP ERC 29/19) and the Ethics Review Committee of Colombo South Teaching Hospital (Reference number 915). The research results will be published in peer-reviewed publications and presented at international conferences. Trial registration number SLCTR/2020/022.

High prevalence of Aedes aegypti and Ae. albopictus vectors and dengue incidence as well as the presence of the four dengue virus serotypes underscore the need for effective and simple tools to monitor dengue vectors in Sri Lanka. Field studies were therefore undertaken with inexpensive gravid female trap (GFT) fabricated from local materials in Jaffna city in northern Sri Lanka. The study was initiated in April 2022, and GFT-based mosquito collection was conducted from June 2022 to April 2023. Five blocks of 30 to 40 houses, were selected in areas of high dengue prevalence in Jaffna city. Thirty houses were selected within each block and provided with five traps to be placed indoor and outdoor in each house. Conventional larval indices were determined at the beginning, middle and end of the study. Nine rounds of GFT collections were performed to identify and quantify trapped mosquitoes, their parity, and infection with virus serotypes. A total of 2177 and 3069 Aedes were collected respectively in indoor and outdoor GFTs, during nine rounds of collections and identified at the species level where possible. A total of 679 and 433 Ae. aegypti and Ae. albopictus were collected in indoor traps and 377 and 1288 in outdoor traps respectively. Adult and larval indices decreased respectively by 50% and 100% by the end of the study. Parous mosquitoes comprised 93% (of 120) and 94% (of 288) of the collected Ae. aegypti and Ae. albopictus respectively. In 110 pools of female Ae. aegypti and Ae. albopictus screened for virus serotype by PCR, five pools of Ae. aegypti and six pools of Ae. albopictus from both indoor and outdoor collections were positive for DENV-2. GFTs fabricated with locally available and inexpensive materials described here can be effective for monitoring the prevalence of Aedes vector species, parity and dengue virus infection status. The larval indices suggest that the use of GFTs can contribute to reducing dengue transmission.