Long-Term Persistence of Chikungunya Virus-Associated Manifestations and Anti-Chikungunya Virus Antibody in Southern Thailand: 5 Years After an Outbreak in 2008-2009

Chikungunya virus infection under high glucose environment reverts insulin unresponsiveness and promotes cellular metabolic shift to increase anaplerosis and virion production

AIMS

Chikungunya virus (CHIKV) is a medically significant arbovirus responsible for Chikungunya fever (CHIKF), a debilitating disease marked by persistent joint and muscle pain. The most severe outcomes of CHIKF, including mortality, are frequently observed in individuals with comorbidities diabetes mellitus (DM). This study aimed to investigate how varying glucose concentrations influence CHIKV infection.

MATERIALS AND METHODS

Human umbilical vein endothelial cells (HUVEC) were cultured in normal glucose (NG - 5.5 mM glucose) or high glucose (HG - 25 mM glucose) to mimic normoglycemia and hyperglycemia conditions. Cells were infected with CHIKV and changes in host glucose metabolism were evaluated. Metabolic flux, viral replication, and cellular insulin sensitivity were assessed through biochemical, molecular analyses and metabolomics.

KEY FINDINGS

CHIKV infection modulates host cell metabolism in a glucose-dependent manner. Under NG conditions, the virus regulates glucose metabolism to support replication and virion production. In contrast, HG environments enhance viral replication, exploiting the altered metabolic landscape. Notably, CHIKV restores insulin sensitivity in HG conditions, leading to increased glucose uptake. It also promotes anaplerotic reactions by diverting tricarboxylic acid (TCA) cycle intermediates toward amino acid synthesis and upregulates glycolytic flux into the hexosamine biosynthesis pathway (HBP).

SIGNIFICANCE

These findings provide mechanistic insight into how hyperglycemia associated with DM can exacerbate CHIKV pathogenesis. The virus's ability to hijack and redirect host metabolic processes in high glucose environments may underline the worsened disease severity observed in diabetic patients. Understanding these interactions could inform targeted therapeutic strategies for managing CHIKF in individuals with metabolic comorbidities.

Chikungunya and other viral arthritis

Several viruses cause acute and chronic arthritis. Millions of people suffered from Chikungunya(CHIK) during the recent epidemics/outbreaks in Asia, Africa and the Americas. Almost 20-40 % failed to recover completely and suffered from chronic pain and arthritis sequel. A wide spectrum of clinical phenotypic arthritis was described. Non-specific arthralgias(NSA) and soft tissue pains were predominant although inflammatory arthritis (mostly undifferentiated)(IA-U) was substantial. Specifically, rheumatoid arthritis(RA) and spondyloarthritis(SpA) like disorders were described. The frequency of biomarkers such as rheumatoid factor(RF) was low. Arthritis was mostly non-erosive in population studies. Abnormal immune mechanisms and persistent specific CHIK virus (CHIKV) IgM and IgG antibodies were shown. The etiopathogenetic evidence was divided between intense joint tissue inflammation due to prolonged virus persistence and abnormal autoimmune mechanisms. There was no specific therapy. The symptomatic management was often combined with an empirical use of disease modifying anti rheumatoid drugs and steroids. Substantial research is required to address knowledge gaps and unravel evidence-based medicine.

A brief overview of chikungunya-related pain

Pain is an important symptom associated with the arboviral disease caused by the Chikungunya virus (CHIKV). For a significant number of patients, this symptom can persist for months or even years, negatively affecting their quality of life. Unfortunately, pharmacological options for this condition are limited and only partially effective, as the underlying mechanisms associated with CHIKV-induced pain are still poorly understood. The re-emergence of CHIKV has led to new outbreaks, and the expected high prevalence of pain in these global events requires new scientific advances to find more effective solutions. Here we review the main aspects of pain caused by CHIKV infection, such as the anatomy of the affected sites, the prevalence and management of this symptom, the diversity of possible cellular and molecular mechanisms, and finally highlight a promising meningeal pathway to elucidate the mechanisms involved in the unsolved problem of CHIKV-associated pain.

Clinical manifestations associated with the chronic phase of Chikungunya Fever: A systematic review of prevalence

INTRODUCTION

The aim of this systematic review of prevalence is to observe and discuss the clinical manifestations of Chikungunya Virus disease in its chronic phase.

METHODS

To be eligible, the observational studies should accompany the individuals for at least six months. The research was conducted using electronic databases MEDLINE and EMBASE. The methodological quality was evaluated using the "Joanna Briggs Institute's critical appraisal checklist for studies reporting prevalence data" tool.

RESULTS

The search has found 175 articles. The application of the inclusion criteria defined a total of 29 selected studies. From the included studies, only one did not present arthralgia as a prevalent symptom in the chronic phase. Other signs and symptoms observed were: fatigue; sleep disorders; myalgia; skin lesions; depression; digestive disorders.

CONCLUSION

Because it is an often incapacitating symptom, arthralgia can affect the individuals' quality of life, with implications in their social and work life. Since the chronic phase is common in infected individuals, all levels of health care should be prepared to monitor, in the medium to long term, the patients affected by this condition.

Chikungunya Virus Vaccines: A Review of IXCHIQ and PXVX0317 from Pre-Clinical Evaluation to Licensure

Chikungunya virus is an emerging mosquito-borne alphavirus that causes febrile illness and arthritic disease. Chikungunya virus is endemic in 110 countries and the World Health Organization estimates that it has caused more than 2 million cases of crippling acute and chronic arthritis globally since it re-emerged in 2005. Chikungunya virus outbreaks have occurred in Africa, Asia, Indian Ocean islands, South Pacific islands, Europe, and the Americas. Until recently, no specific countermeasures to prevent or treat chikungunya disease were available. To address this need, multiple vaccines are in human trials. These vaccines use messenger RNA-lipid nanoparticles, inactivated virus, and viral vector approaches, with a live-attenuated vaccine VLA1553 and a virus-like particle PXVX0317 in phase III testing. In November 2023, the US Food and Drug Administration (FDA) approved the VLA1553 live-attenuated vaccine, which is marketed as IXCHIQ. In June 2024, Health Canada approved IXCHIQ, and in July 2024, IXCHIQ was approved by the European Commission. On August 13, 2024, the US FDA granted priority review for PXVX0317. The European Medicine Agency is considering accelerated assessment review of PXVX0317, with potential for approval by both agencies in 2025. In this review, we summarize published data from pre-clinical and clinical trials for the IXCHIQ and PXVX0317 vaccines. We also discuss unanswered questions including potential impacts of pre-existing chikungunya virus immunity on vaccine safety and immunogenicity, whether long-term immunity can be achieved, safety in children, pregnant, and immunocompromised individuals, and vaccine efficacy in people with previous exposure to other emerging alphaviruses in addition to chikungunya virus.

Elevated Complement Activation Fragments and C1q-Binding Circulating Immune Complexes in Varied Phases of Chikungunya Virus Infection

Chikungunya virus (CHIKV) is a causative agent of a disease continuum, ranging from an acute transient chikungunya fever to chronic incapacitating viral arthralgia. The interaction between anti-CHIKV antibodies and the complement system has recently received attention. However, the contribution of complement activation in CHIKV-induced pathologies has not been fully elucidated. The present study was undertaken to delineate the possible contribution of complement activation in CHIKV-induced disease progression. In this study, using plasma specimens of chikungunya patients in the acute, chronic, and recovered phases of infection, we explicated the involvement of complement activation in CHIKV disease progression by ELISAs and Bio-Plex assays. Correlation analysis was carried out to demonstrate interrelation among C1q-binding IgG-containing circulating immune complexes (CIC-C1q), complement activation fragments (C3a, C5a, sC5b-9), and complement-modulated pro-inflammatory cytokines (IL-1β, IL-18, IL-6, and TNF-α). We detected elevated complement activation fragments, CIC-C1q, and complement-modulated cytokines in the varied patient groups compared with the healthy controls, indicating persistent activation of the complement system. Furthermore, we observed statistically significant correlations among CIC-C1q with complement activation fragments and C3a with complement modulatory cytokines IL-1β, IL-6, and IL-18 during the CHIKV disease progression. Taken together, the current data provide insight into the plausible association between CICs, complement activation, subsequent complement modulatory cytokine expression, and CHIKV etiopathology.

Chikungunya seroprevalence, force of infection, and prevalence of chronic disability after infection in endemic and epidemic settings: a systematic review, meta-analysis, and modelling study

BACKGROUND

Chikungunya is an arboviral disease transmitted by Aedes aegypti and Aedes albopictus mosquitoes with a growing global burden linked to climate change and globalisation. We aimed to estimate chikungunya seroprevalence, force of infection (FOI), and prevalence of related chronic disability and hospital admissions in endemic and epidemic settings.

METHODS

In this systematic review, meta-analysis, and modelling study, we searched PubMed, Ovid, and Web of Science for articles published from database inception until Sept 26, 2022, for prospective and retrospective cross-sectional studies that addressed serological chikungunya virus infection in any geographical region, age group, and population subgroup and for longitudinal prospective and retrospective cohort studies with data on chronic chikungunya or hospital admissions in people with chikungunya. We did a systematic review of studies on chikungunya seroprevalence and fitted catalytic models to each survey to estimate location-specific FOI (ie, the rate at which susceptible individuals acquire chikungunya infection). We performed a meta-analysis to estimate the proportion of symptomatic patients with laboratory-confirmed chikungunya who had chronic chikungunya or were admitted to hospital following infection. We used a random-effects model to assess the relationship between chronic sequelae and follow-up length using linear regression. The systematic review protocol is registered online on PROSPERO, CRD42022363102.

FINDINGS

We identified 60 studies with data on seroprevalence and chronic chikungunya symptoms done across 76 locations in 38 countries, and classified 17 (22%) of 76 locations as endemic settings and 59 (78%) as epidemic settings. The global long-term median annual FOI was 0·007 (95% uncertainty interval [UI] 0·003-0·010) and varied from 0·0001 (0·00004-0·0002) to 0·113 (0·07-0·20). The highest estimated median seroprevalence at age 10 years was in south Asia (8·0% [95% UI 6·5-9·6]), followed by Latin America and the Caribbean (7·8% [4·9-14·6]), whereas median seroprevalence was lowest in the Middle East (1·0% [0·5-1·9]). We estimated that 51% (95% CI 45-58) of people with laboratory-confirmed symptomatic chikungunya had chronic disability after infection and 4% (3-5) were admitted to hospital following infection.

INTERPRETATION

We inferred subnational heterogeneity in long-term average annual FOI and transmission dynamics and identified both endemic and epidemic settings across different countries. Brazil, Ethiopia, Malaysia, and India included both endemic and epidemic settings. Long-term average annual FOI was higher in epidemic settings than endemic settings. However, long-term cumulative incidence of chikungunya can be similar between large outbreaks in epidemic settings with a high FOI and endemic settings with a relatively low FOI.

FUNDING

International Vaccine Institute.

Extra-articular Manifestations of Chikungunya

Chikungunya fever (CHIK) is a neglected tropical disease associated with chronic arthritis. CHIK is usually a self-limiting condition; however, extra-articular manifestations present as atypical illness in a minority of patients. These atypical features may mimic other conditions and potentially distract physicians from the true diagnosis. This review analyzes the evidence of many unusual extra-articular manifestations reported in cases of CHIK. Depending on the affected system, these unusual manifestations include encephalitis, myocarditis, acute interstitial nephritis, cutaneous manifestations, acute anterior uveitis, abdominal pain, and depression. In addition, coinfections and comorbidities may cause atypical illness and obscure the diagnosis. Further studies are required to clarify the pathophysiology and natural history of CHIK, as it remains a burdening condition. Exploring its atypical symptoms may be the missing scientific piece of this puzzle.

Statistical modeling for identifying chikungunya high-risk areas of two large-scale outbreaks in Thailand's southernmost provinces

Chikungunya fever (CHIKF) has re-emerged in the southernmost Thailand and presents a significant threat to public health. The problem areas can be identified using appropriate statistical models. This study aimed to determine the geographic epidemic patterns and high-risk locations. Data on CHIKF's case characteristics, including age, gender, and residence sub-district, were obtained from the Office of Disease Prevention and Control of Thailand from 2008 to 2020. A logistic model was applied to detect illness occurrences. After removing records with no cases, a log-linear regression model was used to determine the incidence rate. The results revealed that two large-scale infections occurred in the southernmost provinces of Thailand between 2008 and 2010, and again between 2018 and 2020, indicating a 10-year epidemic cycle. The CHIKF occurrence in the first and second outbreaks was 28.4% and 15.5%, respectively. In both outbreaks of occurrence CHIKF, adolescents and working-age groups were the most infected groups but the high incidence rate of CHIKF was elderly groups. The first outbreak had a high occurrence and incidence rate in 39 sub-districts, the majority of which were in Narathiwat province, whilst the second outbreak was identified in 15 sub-districts, the majority of which were in Pattani province. In conclusion, the CHIKF outbreak areas can be identified and addressed by combining logistic and log-linear models in a two-step process. The findings of this study can serve as a guide for developing a surveillance strategy or an earlier plan to manage or prevent the CHIKF outbreak.

The clinical manifestation and the influence of age and comorbidities on long-term chikungunya disease and health-related quality of life: a 60-month prospective cohort study in Curaçao

BACKGROUND

Persistent rheumatic symptoms and its impact on health-related quality of life (QoL), induced by the Indian Ocean Lineage (IOL) chikungunya virus (CHIKV) genotype have been widely studied. In 2014, a major CHIKV outbreak of the Asian genotype occurred in Curaçao, after which we established a longitudinal cohort in 2015, to follow the long-term CHIKV sequalae. Currently, the long-term clinical manifestations and its impact on QoL induced by the Asian CHIKV genotype, followed prospectively through time, and the association of age and comorbidities with rheumatic symptoms persistence, 60 months (M60) after disease onset is unknown.

METHODS

The cohort of 304 laboratory confirmed patients were followed prospectively in time at 3-16 months (M3-16), 30 months (M30), and M60 after disease onset. Demographic and clinical characteristics, and the 36-item short-form survey (SF-36) QoL status were collected through questionnaires. At M60, QoL scores were compared to general population (CHIK-) norms.

RESULTS

A total of 169 (56%) patients participated (74.6% female, mean age 56.1 years) at all time points, 107 (63%) were classified as recovered and 62 (37%) as affected. The affected patients reported an increase in the prevalence of arthralgia (P .001) and arthralgia in the lower extremities (P < .001), at M30 compared to M3-16. At M60, in comparison to recovered patients, affected patients reported a higher prevalence of recurrent rheumatic symptoms of moderate to severe pain, irrespective of age and comorbidities, and a higher prevalence of non-rheumatic symptoms (P < .001). Arthralgia in the upper (odds ratio (OR): 4.79; confidence interval (CI): 2.01-11.44; P < .001) and lower (OR: 8.68; CI: 3.47-21.69; P < .001) extremities, and headache (OR: 3.85; CI: 1.40-10.54; P = .009) were associated with being affected. The SF-36 QoL scores of the recovered patients were less impaired over time compared to the QoL scores of the affected patients. At M60, the QoL scores of the recovered patients were comparable to the CHIK- QoL scores.

CONCLUSIONS

Rheumatic and non-rheumatic symptoms, and QoL impairment may persist, 60 months following infection with the Asian CHIKV genotype, similar to the IOL genotype disease sequelae. Further research is needed to follow the clinical manifestations and QoL impact of each CHIKV genotype.

Determinants of Health-Related Quality of Life in Chronic Chikungunya Disease in Guadeloupe

Chronic chikungunya disease is associated with a poor quality of life and a variety of symptoms, not restricted to the musculoskeletal system. Patients with chronic chikungunya disease in Guadeloupe were evaluated in order to identify the main factors determining the quality of life. Patients were followed up at a mean of 36 months after chikungunya infection, undergoing detailed clinical examination for musculoskeletal involvement, with assessment of subjective symptoms and the impact on mood, physical activity, and quality of life (SF12). Patients had extensive musculoskeletal involvement shown by tenderness in 9 ± 4 joints and stiffness in 5 ± 4 joints. SF12 physical and mental component scores showed a poor health-related quality of life. Measures of joint pain, stiffness, and inflammation contributed to impaired quality of life scores. In addition, fatigue and interrupted sleep appeared to be important predictors for physical aspects of quality of life. The emergence of anxiodepressive syndromes post-chikungunya infection was associated with both physical and mental component scores of SF12. These data confirm that musculoskeletal symptoms are not the only determinants of quality of life in chronic chikungunya disease. Follow-up of patients should include assessment and management of fatigue, poor sleep quality, and anxiodepressive syndromes.

Immunoglobulin G Subclass Response After Chikungunya Virus Infection

Various vaccines are under development to prevent chikungunya (CHIKV) infection. For the assessment of the CHIKV vaccine-induced antibody response, it is extremely important to understand antibody response after the infection has occurred. Previously, we assessed IgG response in samples from healthy donors using I-CHIKV and found that IgG1 was the predominant subclass induced after CHIKV infection followed by IgG4. However, IgG3 subclass induction is reported in serum samples from patients with acute CHIKV infection. Therefore, in this study, we evaluated serum/plasma from samples of patients with acute CHIKV infection for the presence of IgG and IgG subclasses against I-CHIKV and recombinant E2 protein (rE2). Out of 44 samples that were positive against I-CHIKV, 43 were found reactive against rE2. The positivity of IgG1 either alone or together with other IgG subclasses using I-CHIKV was 89% samples, while 86% samples were positive using rE2. High titers of IgG1 are obtained with I-CHIKV (67%), while raised IgG4 levels are detected using rE2p (72%) in the samples that are positive for both these subclasses. Testing of 22 samples for neutralizing antibodies revealed 100% IgG1 positivity and neutralizing antibodies in 21, 1 sample negative for both. Overall, these data will be useful in assessing IgG subclass-specific CHIKV neutralization and response after CHIKV immunization.

Risk factors for infection with chikungunya and Zika viruses in southern Puerto Rico: A community-based cross-sectional seroprevalence survey

Chikungunya virus (CHIKV) caused a large outbreak in Puerto Rico in 2014, followed by a Zika virus (ZIKV) outbreak in 2016. Communities Organized for the Prevention of Arboviruses (COPA) is a cohort study in southern Puerto Rico, initiated in 2018 to measure arboviral disease risk and provide a platform to evaluate interventions. To identify risk factors for infection, we assessed prevalence of previous CHIKV infection and recent ZIKV and DENV infection in a cross-sectional study among COPA participants. Participants aged 1-50 years (y) were recruited from randomly selected households in study clusters. Each participant completed an interview and provided a blood specimen, which was tested by anti-CHIKV IgG ELISA assay and anti-ZIKV and anti-DENV IgM MAC-ELISA assays. We assessed individual, household, and community factors associated with a positive result for CHIKV or ZIKV after adjusting for confounders. During 2018-2019, 4,090 participants were enrolled; 61% were female and median age was 28y (interquartile range [IQR]: 16-41). Among 4,035 participants tested for CHIKV, 1,268 (31.4%) had evidence of previous infection. CHIKV infection prevalence was lower among children 1-10 years old compared to people 11 and older (adjusted odds ratio [aOR] 2.30; 95% CI 1.71-3.08). Lower CHIKV infection prevalence was associated with home screens (aOR 0.51; 95% CI 0.42-0.61) and air conditioning (aOR 0.64; 95% CI 0.54-0.77). CHIKV infection prevalence also varied by study cluster of residence and insurance type. Few participants (16; 0.4%) had evidence of recent DENV infection by IgM. Among 4,035 participants tested for ZIKV, 651 (16%) had evidence of recent infection. Infection prevalence increased with older age, from 7% among 1-10y olds up to 19% among 41-50y olds (aOR 3.23; 95% CI 2.16-4.84). Males had an increased risk of Zika infection prevalence compared with females (aOR 1.31; 95% CI 1.09-1.57). ZIKV infection prevalence also decreased with the presence of home screens (aOR 0.66; 95% CI 0.54-0.82) and air conditioning (aOR 0.69; 95% CI 0.57-0.84). Similar infection patterns were observed for recent ZIKV infection prevalence and previous CHIKV infection prevalence by age, and the presence of screens and air conditioners in the home decreased infection risk from both viruses by as much as 50%.

Age-Dependent Evaluation of Immunoglobulin G Response after Chikungunya Virus Infection

Current chikungunya antibody prevalence and titers are likely to differ based on exposure rates before the 2006 reemergence. For vaccine usage, such data are of immense importance. This study addresses age-stratified IgG titers and its subtypes in Pune, India, endemic for the disease. One hundred seventy serum pools (791 individuals with prior chikungunya exposure, age stratified) from exposed and 15 samples from acute disease phase were screened. Inactivated chikungunya virus (CHIKV)-based indirect ELISA was used to determine anti-CHIKV-IgG and its subtypes. Neutralizing antibody titers (plaque reduction neutralization test [PRNT]) were compared with binding antibody titers (ELISA). Anti-CHIKV-IgG titers along with IgG1 and IgG4 increased till the age-group of 11-15 years and remained comparable thereafter till > 65 years. IgG1 was the predominant IgG subtype detected in all the pools, whereas IgG4 was present in 151/170 pools. Strong correlation of IgG1 was obtained with CHIKV-PRNT50 titers. None of the sample had anti-CHIKV-IgG2, whereas five pools had IgG3 antibody. In the acute-phase serum sample, IgG1 was present in all the samples, whereas IgG4 was present in 8/15 samples. IgG4 was predominant in four samples. During acute phase and at different times postinfection, IgG1 circulated in high titers followed by IgG4. Higher antibody titers in adults reflect reexposures. The data will prove useful in assessing immune response to CHIKV vaccine.

Immunopathogenesis of alphaviruses

Alphaviruses, members of the enveloped, positive-sense, single-stranded RNA Togaviridae family, represent a reemerging public health threat as mosquito vectors expand into new geographic territories. The Old World alphaviruses, which include chikungunya virus, Ross River virus, and Sindbis virus, tend to cause a clinical syndrome characterized by fever, rash, and arthritis, whereas the New World alphaviruses, which consist of Venezuelan equine encephalitis virus, eastern equine encephalitis virus, and western equine encephalitis virus, induce encephalomyelitis. Following recovery from the acute phase of infection, many patients are left with debilitating persistent joint and neurological complications that can last for years. Clues from human cases and studies using animal models strongly suggest that much of the disease and pathology induced by alphavirus infection, particularly atypical and chronic manifestations, is mediated by the immune system rather than directly by the virus. This review discusses the current understanding of the immunopathogenesis of the arthritogenic and neurotropic alphaviruses accumulated through both natural infection of humans and experimental infection of animals, particularly mice. As treatment following alphavirus infection is currently limited to supportive care, understanding the contribution of the immune system to the disease process is critical to developing safe and effective therapies.