Chikungunya virus aches and pains: an emerging challenge

Detection of musculoskeletal inflammatory lesions in patients with chronic chikungunya infection using 3T whole-body magnetic resonance imaging

BACKGROUND

Musculoskeletal inflammatory lesions in chronic Chikungunya virus (CHIKV) infection have not been thoroughly assessed using whole-body magnetic resonance imaging (WBMRI). This study aimed to determine the prevalence of these lesions in such patients.

METHODS

From September 2018 to February 2019, patients with positive Chikungunya-specific serology (Immunoglobulin M/Immunoglobulin G anti-CHIKV), with a history of polyarthralgia for > 6 months prior to MRI with no pre-existing rheumatic disorders, underwent 3T WBMRI and localized MRI. The evaluation focused on musculoskeletal inflammatory lesions correlated with chronic CHIKV infection. Pain levels were assessed using a visual analogue scale on the same day as WBMRI.

RESULTS

The study included 86 patients of whom 26 met the inclusion criteria. All patients reported pain and most (92.3%) categorized it as moderate or severe. The most common finding across joints was effusion, particularly in the tibiotalar joint (57.7%) and bursitis, with the retrocalcaneal bursa most affected (48.0%). Tenosynovitis was prevalent in the flexor compartment of the hands (44.2%), while Kager fat pad and soleus edema were also observed. Bone marrow edema-like signals were frequently seen in the sacroiliac joints (19.2%). Most WBMRI findings were classified as mild.

CONCLUSIONS

This study represents the first utilization of 3T WBMRI to assess musculoskeletal inflammatory disorders in chronic CHIKV infection. The aim was to identify the most affected joints and prevalent lesions, providing valuable insights for future research and clinical management of this condition regarding understanding disease pathophysiology, developing targeted treatment strategies, and using advanced imaging techniques in the assessment of musculoskeletal manifestations.

Interleukin-17 contributes to Ross River virus-induced arthritis and myositis

Arthritogenic alphaviruses are mosquito-borne viruses that are a major cause of infectious arthropathies worldwide, and recent outbreaks of chikungunya virus and Ross River virus (RRV) infections highlight the need for robust intervention strategies. Alphaviral arthritis can persist for months after the initial acute disease, and is mediated by cellular immune responses. A common strategy to limit inflammation and pathology is to dampen the overwhelming inflammatory responses by modulating proinflammatory cytokine pathways. Here, we investigate the contribution of interleukin-17 (IL-17), a cytokine involved in arthropathies such as rheumatoid arthritis, in the development RRV-induced arthritis and myositis. IL-17 was quantified in serum from RRV-infected patients, and mice were infected with RRV and joints and muscle tissues collected to analyse cellular infiltrates, tissue mRNA, cytokine expression, and joint and muscle histopathology. IL-17 expression was increased in musculoskeletal tissues and serum of RRV-infected mice and humans, respectively. IL-17–producing T cells and neutrophils contributed to the cellular infiltrate in the joint and muscle tissue during acute RRV disease in mice. Blockade of IL-17A/F using a monoclonal antibody (mAb) reduced disease severity in RRV-infected mice and led to decreased proinflammatory proteins, cellular infiltration in synovial tissues and cartilage damage, without affecting viral titers in inflamed tissues. IL-17A/F blockade triggered a shift in transcriptional profile of both leukocyte infiltrates and musculoskeletal stromal cells by downregulating proinflammatory genes. This study highlights a previously uncharacterized role for an effector cytokine in alphaviral pathology and points towards potential therapeutic benefit in targeting IL-17 to treat patients presenting with RRV-induced arthropathy.

Some viruses transmitted by mosquitoes cause painful and debilitating arthritis, which manifests both as an acute form shortly following infection, and a chronic form long after the initial symptoms have subsided. These viruses, termed arboviruses, are difficult to control and there are currently no specific treatments to alleviate the pain and loss of mobility. Arthritis caused by arboviruses shares similarities with a non-infectious, autoimmune form of arthritis called rheumatoid arthritis (RA). In RA, an immune molecule termed interleukin-17, or IL-17, has been shown to drive arthritis and treatments that target or block IL-17 are being developed to treat RA. Here, we asked whether arthritis caused by an arbovirus, Ross River virus (RRV), was also associated with elevated IL-17 in humans and mice. Disease severity in mice was associated with high IL-17 expression in the feet and muscle, and blocking IL-17 using an anti-IL-17 monoclonal antibody ameliorated disease in mice infected with RRV. Our study provides new information on a molecule that is implicated in arthritic inflammation, and could be targeted to treat disease caused by arthritogenic arboviruses.

Long-Term Persistence of Serum-Specific Anti-Chikungunya IgM Antibody - A Case Series of Brazilian Patients

The persistence of serum-specific anti-chikungunya IgM antibodies (CHIKV-IgM) can vary after chikungunya fever (CHIK) infection. However, the factors related to its production are not yet known. We described a case series drawn up from data collected from 57 patients between 12 and 36 months after the acute phase of CHIK infection in Northeastern Brazil. CHIKV-IgM was detectable in 7/57 (12.3%) patients after 28.3 months of infection. No frequency differences in chronic musculoskeletal manifestations and underlying conditions were detected between patients with or without CHIKV-IgM. CHIKV-IgM was detected for up to 35 months in Brazilian patients after CHIK infection.

Development and Validation of a Rapid Lateral Flow E1/E2-Antigen Test and ELISA in Patients Infected with Emerging Asian Strain of Chikungunya Virus in the Americas

Since its 2013 emergence in the Americas, Chikungunya virus (CHIKV) has posed a serious threat to public health. Early and accurate diagnosis of the disease, though currently lacking in clinics, is integral to enable timely care and epidemiological response. We developed a dual detection system: a CHIKV antigen E1/E2-based enzyme-linked immunosorbent assay (ELISA) and a lateral flow test using high-affinity anti-CHIKV antibodies. The ELISA was validated with 100 PCR-tested acute Chikungunya fever samples from Honduras. The assay had an overall sensitivity and specificity of 51% and 96.67%, respectively, with accuracy reaching 95.45% sensitivity and 92.03% specificity at a cycle threshold (Ct) cutoff of 22. As the Ct value decreased from 35 to 22, the ELISA sensitivity increased. We then developed and validated two lateral flow tests using independent antibody pairs. The sensitivity and specificity reached 100% for both lateral flow tests using 39 samples from Colombia and Honduras at Ct cutoffs of 20 and 27, respectively. For both lateral flow tests, sensitivity decreased as the Ct increased after 27. Because CHIKV E1/E2 are exposed in the virion surfaces in serum during the acute infection phase, these sensitive and specific assays demonstrate opportunities for early detection of this emerging human pathogen.

Chikungunya-Induced Arthritis in Reunion Island: A Long-Term Observational Follow-Up Study Showing Frequently Persistent Joint Symptoms, Some Cases of Persistent Chikungunya Immunoglobulin M Positivity, and No Anticyclic Citrullinated Peptide Seroconversion After 13 Years

Background

Reunion Island was struck by a massive Chikungunya outbreak in 2005–2006. Chikungunya infection is characterized by inflammatory joint symptoms, which may evolve into chronic arthritis.

Methods

In this long-term longitudinal observational monocentric study, after the 2005–2006 outbreak in Reunion Island, 159 patients were first referred to a rheumatologist for post-Chikungunya chronic musculoskeletal pain, 73 of them were diagnosed with classifiable Chikungunya-related chronic inflammatory rheumatic diseases (>3 month symptom duration from the initial viral infection). Thirty of these 73 patients were clinically evaluated by a second rheumatologist in 2018–2019. The main objective of this second examination was to estimate the proportion of patients with persistent Chikungunya-related inflammatory joint symptoms after 13 years.

Results

Inflammatory joint symptoms persisted in 17/30 patients after 13 years (therefore in at least 23.3% of the 73 patients initially diagnosed with Chikungunya-related inflammatory joint symptoms and 10.7% of the 159 patients referred for post-Chikungunya chronic musculoskeletal pain). In the symptom persistence subgroup, the prevalence of positive autoantibodies (antinuclear or ACPA) was significantly higher – without any seroconversion, Chikungunya IgG and IgM levels were higher, long-term IgM positivity and radiographic damage were more frequent. Overall, after 13 years, pain and fatigue levels remained significant, 5 patients were still treated by methotrexate, 3 by TNF-blockers, highlighting long-term Chikungunya-related patient burden.

Conclusions

Such a long-term persistence of Chikungunya-related chronic inflammatory rheumatic diseases had not been reported so far. Furthermore, the long-term Chikungunya IgM positivity we observed in some cases might corroborate the hypothesis of residual viral antigen-driven chronic arthritis.

Manifestations of Atypical Symptoms of Chikungunya during the Dhaka Outbreak (2017) in Bangladesh

Chikungunya (CHIK) has emerged as a major public health concern worldwide. Recently, atypical manifestations are drawing special attention because these might be associated with various complications. Information on atypical manifestations of CHIK is still limited. Here, we analyzed a dataset of 1,326 cases from our recent Dhaka outbreak study to explore the demographics and distributions of atypical manifestations. About 80% of cases reported at least one atypical symptom. Among all atypical symptoms, the most common and unique atypical symptom was joint pain before fever (90.2%), occurred predominantly in female respondents. Other common symptoms included red eye (68.2%), oral ulcer (37.7%), and dermatological manifestations (27.1%). More than two-thirds of patients reported multiple atypical symptoms. Atypical manifestations were not significantly different across age groups, except ocular complications. This study would be an important resource for clinicians and epidemiologists to understand the diversity of Chikungunya infection and, thus, help in better patient management.

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 fever, a disease caused by chikungunya virus (CHIKV), reemerged and affected over 52,000 people in southern Thailand in 2008 and 2009. The CHIKV strain involved in this outbreak was the East Central South African (ECSA) strain with the E1-A226V mutation. The prevalence of CHIKV-associated chronic discomfort varied by virus lineage. This retrospective cohort study aims to describe the CHIKV-related symptoms persisting in CHIKV-affected patients, related factors, and the presence of anti-CHIKV immunoglobulin G (IgG) antibodies 5 years after the onset of disease. From 5,344 of the study population screened, a total of 89 affected patients reported persistent arthralgia 5 years after the disease onset (nonrecovery rate = 1.7%). Of the 141 affected patients enrolled, 122 cases (86.5%; 77 cases with persistent arthralgia and 45 cases of fully recovered) still had detectable levels of anti-CHIKV IgG antibodies. Long-term persistence of chronic joint symptoms is associated with the severity of the disease during the initial phase of the infection, but not gender, age, or comorbidities. The common manifestations were arthralgia (75.3%), morning joint stiffness (39.0%), muscle pain (19.5%), and occasional joint swelling (16.9%). Chronic joint symptoms could occur in either a fluctuating or a persistent manner and usually caused moderate pain. The joints affected were mainly fingers (71.4%), wrists (51.9%), and knees (50.6%). Most patients had polyarthralgia with symmetrical joint involvement. In some cases with persistent arthralgia, atypical manifestations, including severe depression with suicide attempts, severe weight loss, and severe hair loss, were found, and some patients still experienced severe joint pain.

Stiffness, pain, and joint counts in chronic chikungunya disease: relevance to disability and quality of life

INTRODUCTION/OBJECTIVES

To characterize the importance of musculoskeletal stiffness in a cohort of chikungunya patients with chronic joint symptoms.

METHOD

Eighty-two patients were followed up 3 years after chikungunya infection. Tender and swollen joint counts, a pain intensity scale, Health Assessment Questionnaire-Disability Index (HAQ-DI), and the EuroQol EQ-5D quality of life instrument were completed. A musculoskeletal stiffness questionnaire provided scores for overall stiffness and its components: stiffness severity, physical impact, and psychosocial impact.

RESULTS

Patients had a mean age 51 ± 14 years. Sixty-seven patients were still experiencing chronic arthralgia. Musculoskeletal stiffness was reported by 43/67 patients with arthralgia and 3/15 patients without arthralgia. A physical impact of stiffness was reported by 87% patients and psychosocial impact by 71% patients. Mean tender joint count in patients reporting arthralgia was 6 ± 7, mean pain intensity 65 ± 20 out of 100, mean HAQ-DI was 0.54 ± 0.52, and mean EQ-VAS global health perception was 68 ± 62 out of 100. Stiffness severity was correlated with tender joint counts (ρ = 0.46) and pain intensity (ρ = 0.40). All three measures were equally well correlated with the EuroQol-VAS global health perception. Pain and tender joints were better correlated with the HAQ-DI (ρ = 0.68 and ρ = 0.63), but stiffness was more strongly correlated with several quality of life domains, including mobility. Swollen joints were a poor predictor of outcomes.

CONCLUSIONS

Musculoskeletal stiffness following chikungunya infection is distinct from arthralgia. It does not always occur in the same patients or with a corresponding intensity. Joint pain and stiffness may be independently associated with disability and quality of life assessments.

Clinical and Laboratory Characteristics of an Acute Chikungunya Outbreak in Bangladesh in 2017

From April to September 2017, Bangladesh experienced a huge outbreak of acute Chikungunya virus infection in Dhaka. This series describes the clinical and laboratory features of a large number of cases (690; 399 confirmed and 291 probable) suffered during that period. This observational study was carried out at Dhaka Medical College Hospital, Bangladesh. The median age of the patients at presentation was 38 years (IQR 30–50) with a male (57.3%) predominance. Hypertension and diabetes were the most common comorbidities. The mean (±SD) duration of fever was 3.7 (±1.4) days. Other common manifestations were arthralgia (99.2%), maculopapular rash (50.2%), morning stiffness (49.7%), joint swelling (48.5%), and headache (37.6%). Cases were confirmed by anti-chikungunya IgG (173; 43.3%), IgM (165; 42.3%), and reverse transcription polymerase chain reaction (44; 11.0%). Important laboratory findings include high erythrocyte sedimentation rate (156; 22.6%), raised serum glutamic pyruvic transaminase (73; 10.5%), random blood sugar (54; 7.8%), leukopenia (72; 10.4%), thrombocytopenia (41; 5.9%), and others. The oligo-articular (453; 66.1%) variety of joint involvement was significantly more common compared with the poly-articular (237; 34.5%) variety. Commonly involved joints were the wrist (371; 54.1%), small joints of the hand (321; 46.8%), ankle (251; 36.6%), knee (240; 35.0%), and elbow (228; 33.2%). Eleven cases were found to be complicated with neurological involvement and two of them died. Another patient died due to myocarditis. Public health experts, clinicians, and policymakers could use the results of this study to construct the future strategy tackling chikungunya in Bangladesh and other epidemic countries.

Seroprevalence and Symptomatic Attack Rate of Chikungunya Virus Infection, United States Virgin Islands, 2014-2015

When introduced into a naïve population, chikungunya virus generally spreads rapidly, causing large outbreaks of fever and severe polyarthralgia. We randomly selected households in the U.S. Virgin Islands (USVI) to estimate seroprevalence and symptomatic attack rate for chikungunya virus infection at approximately 1 year following the introduction of the virus. Eligible household members were administered a questionnaire and tested for chikungunya virus antibodies. Estimated proportions were calibrated to age and gender of the population. We enrolled 509 participants. The weighted infection rate was 31% (95% confidence interval [CI]: 26-36%). Among those with evidence of chikungunya virus infection, 72% (95% CI: 65-80%) reported symptomatic illness and 31% (95% CI: 23-38%) reported joint pain at least once per week approximately 1 year following the introduction of the virus to USVI. Comparing rates from infected and noninfected study participants, 70% (95% CI: 62-79%) of fever and polyarthralgia and 23% (95% CI: 9-37%) of continuing joint pain in patients infected with chikungunya virus were due to their infection. Overall, an estimated 43% (95% CI: 33-52%) of the febrile illness and polyarthralgia in the USVI population during the outbreak was attributable to chikungunya virus and only 12% (95% CI: 7-17%) of longer term joint pains were attributed to chikungunya virus. Although the rates of infection, symptomatic disease, and longer term joint symptoms identified in USVI are similar to other outbreaks of the disease, a lower proportion of acute fever and joint pain was found to be attributable to chikungunya virus.

Establishment and Comparison of Pathogenicity and Related Neurotropism in Two Age Groups of Immune Competent Mice, C57BL/6J Using an Indian Isolate of Chikungunya Virus (CHIKV)

Chikungunya (CHIK) is a febrile arboviral illness caused by chikungunya virus (CHIKV) and has been identified in more than 60 countries across the globe. A major public health concern, the infection occurs as an acute febrile phase and a chronic arthralgic phase. The disease manifests differently in different age groups that can range from asymptomatic infection in the younger age group to a prolonged chronic phase in the elderly population. The present study was undertaken to evaluate strain-specific pathogenesis of ECSA genotype of CHIKV strains derived from clinical isolates in adult C57BL/6J mice model. The strain that was pathogenic and developed distinct acute and post-acute phase of CHIK infection was further evaluated for dose-dependent pathogenesis. Upon arriving on the optimal dose to induce clinical symptoms in the mice, the disease progression was evaluated across the acute and the post-acute phase of infection for a period of 15 days post-infection in two age groups of mice, namely eight weeks old and 20 weeks old mice groups. Biochemical, hematological, and virology attributes were measured and correlated to morbidity and linked neurotropism and limb thickness in the two age groups. Our results show that CHIKV exhibit strain-specific pathogenesis in C57BL/6J mice. Distinct dissimilarities were observed between the two age groups in terms of pathogenesis, viral clearance and host response to CHIKV infection.

Systems analysis of subjects acutely infected with the Chikungunya virus

The largest ever recorded epidemic of the Chikungunya virus (CHIKV) broke out in 2004 and affected four continents. Acute symptomatic infections are typically associated with the onset of fever and often debilitating polyarthralgia/polyarthritis. In this study, a systems biology approach was adopted to analyze the blood transcriptomes of adults acutely infected with the CHIKV. Gene signatures that were associated with viral RNA levels and the onset of symptoms were identified. Among these genes, the putative role of the Eukaryotic Initiation Factor (eIF) family genes and apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC3A) in the CHIKV replication process were displayed. We further compared these signatures with signatures induced by the Dengue virus infection and rheumatoid arthritis. Finally, we demonstrated that the CHIKV in vitro infection of murine bone marrow-derived macrophages induced IL-1 beta production in a mechanism that is significantly dependent on the inflammasome NLRP3 activation. The observations provided valuable insights into virus-host interactions during the acute phase and can be instrumental in the investigation of new and effective therapeutic interventions.

The Chikungunya virus (CHIKV) has infected millions of people worldwide and presents a serious public health issue. Acute symptomatic infections caused by contracting this mosquito-transmitted arbovirus are typically associated with an abrupt onset of fever and often debilitating polyarthralgia/ polyarthritis, as well as prolonged periods of disability in some patients. These dramatic effects call for a careful evaluation of the molecular mechanisms involved in this puzzling infection. By analyzing the blood transcriptome of adults acutely infected with CHIKV, we were able to provide a detailed picture of the early molecular events induced by the infection. Additionally, the systems biology approach revealed genes that can be investigated extensively as probable therapeutic targets for the disease.

The Clinical Features, Pathogenesis and Methotrexate Therapy of Chronic Chikungunya Arthritis

Chikungunya fever (CHIKF) is an emerging viral infection that has spread widely, along with its Aedes vectors, throughout the tropics and beyond, causing explosive epidemics of acute illness and persistent disabling arthritis. The rheumatic symptoms associated with chikungunya virus (CHIKV) infection include polyarthralgia, polyarthritis, morning stiffness, joint edema, and erythema. Chronic CHIK arthritis (CCA) often causes severe pain and associated disability. The pathogenesis of CCA is not well understood. Proposed hypotheses include the persistence of a low level of replicating virus in the joints, the persistence of viral RNA in the synovium, and the induction of autoimmunity. In this review, we describe the main hypotheses of CCA pathogenesis, some of which support methotrexate (MTX) treatment which has been shown to be effective in preliminary studies in CCA.

Comprehensive innate immune profiling of chikungunya virus infection in pediatric cases

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes global epidemics of debilitating disease worldwide. To gain functional insight into the host cellular genes required for virus infection, we performed whole-blood RNA-seq, 37-plex mass cytometry of peripheral blood mononuclear cells (PBMCs), and serum cytokine measurements of acute- and convalescent-phase samples obtained from 42 children naturally infected with CHIKV Semi-supervised classification and clustering of single-cell events into 57 sub-communities of canonical leukocyte phenotypes revealed a monocyte-driven response to acute infection, with the greatest expansions in "intermediate" CD14++CD16+ monocytes and an activated subpopulation of CD14+ monocytes. Increases in acute-phase CHIKV envelope protein E2 expression were highest for monocytes and dendritic cells. Serum cytokine measurements confirmed significant acute-phase upregulation of monocyte chemoattractants. Distinct transcriptomic signatures were associated with infection timepoint, as well as convalescent-phase anti-CHIKV antibody titer, acute-phase viremia, and symptom severity. We present a multiscale network that summarizes all observed modulations across cellular and transcriptomic levels and their interactions with clinical outcomes, providing a uniquely global view of the biomolecular landscape of human CHIKV infection.

Immunomodulatory drug methotrexate used to treat patients with chronic inflammatory rheumatisms post-chikungunya does not impair the synovial antiviral and bone repair responses

Chikungunya virus (CHIKV) is a mosquito-transmitted RNA alphavirus causing major outbreaks of infectious chronic inflammatory rheumatisms (CIR). Recently, methotrexate (MTX), a disease modifying anti-rheumatic drug has been used successfully to treat patients suffering from rheumatoid-like arthritis post-CHIK but its immunomodulatory activity in the context of viral persistence has been a matter of concerns. We herein used a model of primary human synovial fibroblasts (HSF) and the synthetic molecule polyriboinosinic:polyribocytidylic acid (PIC) to mimic chronic infectious settings in the joints of CHIKV infected patients. The innate antiviral immune and inflammatory responses were investigated in response to MTX used at the therapeutic concentration of 1 μM. We found that MTX did not affect cellular viability as indicated by the LDH release assay. By quantitative RT-PCR, we observed that HSF responded robustly to PIC by increasing ISG15 and IFNβ mRNA levels. Furthermore, PIC upregulated the mRNA expression of two of the major pattern recognition receptors, RIG-I and MDA5 involved in the innate immune detection of viral RNA. MTX did not impact the antiviral response of PIC on ISG15, IFNβ, RIG-I and MDA5 mRNA expressions. MTX alone or combined with PIC did not affect the expression of proinflammatory CCL2 and CXCL8 chemokines. PIC strongly upregulated the mRNA and protein expression of osteoclastogenic factors (IL-6, GM-CSF but not RANKL). Critically, MTX treatment alone or combined with PIC did not affect the expression of all three tested osteoclastogenic cytokines. We found that MTX alone did not increase the capacity of CHIKV to infect and replicate in HSF. In conclusion, our study argues for a beneficial effect of MTX to treat CIR post-CHIKV given that it does not critically impact the antiviral, the proinflammatory and the bone tissue remodeling responses of synovial cells.

Chikungunya is a mosquito-borne virus (CHIKV) and has been incriminated in the development of arthralgia (pain of the joint) and arthritis particularly in elderly patients. Methotrexate (MTX) has been used widely to effectively treat these chronic rheumatic symptoms. Using a model of primary human joint fibroblasts (HSF), we investigated the capacity of the MTX immunosuppressive drug to affect the immune antiviral and inflammatory responses essential to clear the virus while allowing bone tissue repair. This study is important given that CHIKV and its RNA were shown to persist in the joint for months to years post infection and leading to injuries through ill-characterized mechanisms. The molecule PIC was used to mimic the effect of viral RNA. Interestingly, we found that MTX did not affect the expression of several proinflammatory and bone repair factors by HSF. Remarkably, MTX did not also impair the antiviral response of synovial fibroblasts. Our study revealed for the first time that MTX treatment should be considered as safe even in the context of viral persistence associated with chronic inflammation. MTX will not affect the capacity of the synovial tissue to maintain antiviral mechanism, to control inflammation and to promote bone tissue repair.

Rheumatology science and practice in India

The practice of rheumatology in a country like India presents its own unique challenges, including the need to manage patients in a cost-constrained setting, where the lack of uniform government funding for healthcare merits the need to optimize the use of cheaper medicines, as well as devise innovative strategies to minimize the use of costlier drugs such as biologic disease-modifying agents. Use of immunosuppressive agents is also associated with increased risks of infectious complications, such as the reactivation of tuberculosis. In this narrative review, we provide a flavor of such challenges unique to Rheumatology practice in India, and review the published literature on the management of common rheumatic diseases from India. In addition, we critically review existing guidelines for the management of rheumatic diseases from this part of the world. We also discuss infectious etiologies of rheumatic complaints, such as leprosy, tuberculosis, and Chikungunya arthritis, which are often encountered here, and pose a diagnostic as well as therapeutic challenge for clinicians. There remains a need to identify and test more cost-effective strategies for Indian patients with rheumatic diseases, as well as the requirement for more government participation to enhance scant facilities for the treatment of such diseases as well as foster the development of healthcare services such as specialist nurses, occupational therapists and physiotherapists to enable better management of these conditions.

A Case Report of Chikungunya Fever, Rheumatoid Arthritis, and Felty's Syndrome

INTRODUCTION

Chronic chikungunya (CHIK) arthritis, an inflammatory arthritis, often follows acute CHIK fever (CHIKF), a viral infection. The pathogenesis of chronic CHIK arthritis is poorly characterized, but may resemble other forms of inflammatory arthritis. Clinically, chronic CHIK arthritis sometimes mimics rheumatoid arthritis (RA).

CASE REPORT

We report a patient with well-characterized CHIKF followed 2 months later by chronic CHIK arthritis not only resembling RA clinically, but also associated with RA biomarkers and extra-articular features, including Felty's syndrome (FS).

CONCLUSIONS

We describe this patient's excellent response to methotrexate and discuss the implications her case provides in understanding this important emerging rheumatic disease.

Rheumatism and chronic fatigue, the two facets of post-chikungunya disease: the TELECHIK cohort study on Reunion island

Prolonged fatigue is increasingly reported among chikungunya virus (CHIKV)-infected populations. We investigated the relationships between CHIKV exposure, long-lasting rheumatic musculoskeletal pain (LRMSP) and chronic fatigue. 1094 participants (512 CHIKV seropositive and 582 seronegative) of the TELECHIK population-based cohort were analysed considering the duration of the manifestations throughout an average 2-year follow-up. Weighted prevalence rates and prevalence ratios for LRMSP, idiopathic chronic fatigue (ICF), and chronic fatigue syndrome (CFS)-like illness, both latter syndromes adapted from Centers for Disease Control (CDC)-1994/Fukuda criteria, were compared. Population attributable fractions (PAF) were estimated to assess the contribution of CHIKV infection to each of the three phenotypes. Among 362 adult subjects who had reported either rheumatic pain or fatigue at the onset of the infection, weighted prevalence rates of LRMSP, ICF and CFS-like illness were respectively of 32.9%, 38.7% and 23.9%, and of 8.7%, 8.5% and 7.4% among initially asymptomatic peers (P < 0.01, respectively). Each of the three outcomes was highly attributable to chikungunya (PAF of 43.2%, 36.2% and 41.0%, respectively). In the sub-cohort of CHIKV-infected subjects, LRMSP, ICF and CFS-like illness, which overlapped in 70%, accounted for 53% of the chronic manifestations. In addition to rheumatic disease, chronic fatigue could be considered in caring for patients with chronic chikungunya disease.

Chikungunya fever: General and oral healthcare implications

Chikungunya virus (CHIKV) was first isolated in humans in 1952, following an epidemic in Tanzania. The origin of the name means "to bend forward or become contorted," in reference to the posture adopted by patients due to the joint pain that occurs during the infection. Epidemiology data suggest that by the end of 2015, about 1.6 million people had been infected with CHIKV. The acute period of the disease is characterized by high fever, myalgia, joint pain, and severe and disabling polyarthritis, sometimes accompanied by headache, backache, and maculopapular rash, predominantly on the thorax. Around half of the patients will progress to the subacute and chronic phases, that is manifested by persistent polyarthritis/polyarthralgia, accompanied by morning stiffness and fatigue, which could remain for years. Oral features may include gingivitis possibly as a consequence of arthralgia of the hands leading to limited oral health measures as well as burning sensation and oral mucosal ulceration. Treatment in the acute phase includes acetaminophen, and weak opioids (tramadol or codeine) should be used in cases of severe or refractory pain. For patients who have progressed to the subacute stage and who have not had notable benefit from common analgesics or opioids, NSAIDs, or adjunctive pain medications (anticonvulsants or antidepressants) may be of benefit. In patients with moderate-to-severe musculoskeletal pain or in those who cannot be given or tolerate NSIADs or opiates, prednisolone should be prescribed.

Ultrasonography of Hands and Wrists in the Diagnosis of Complications of Chikungunya Fever

The purpose of this series was to describe the ultrasonographic and radiographic manifestations of changes to the hands and wrists in 50 patients with chronic musculoskeletal symptoms secondary to Chikungunya fever during the 2016 outbreak that occurred in Rio de Janeiro, Brazil. Most of the plain radiographs were normal (62%). The most common ultrasonographic findings were small joint synovitis (84%), wrist synovitis (74%), finger tenosynovitis (70%), and cellulitis (50%). In most cases, power Doppler did not show an increase in synovial vascular flow. The plain radiographs showed no specific findings, whereas the ultrasound images revealed synovial compromise and neural thickening.

Chikungunya Virus: Pathophysiology, Mechanism, and Modeling

Chikungunya virus (CHIKV), a mosquito-transmitted alphavirus, is recurring in epidemic waves. In the past decade and a half, the disease has resurged in several countries around the globe, with outbreaks becoming increasingly severe. Though CHIKV was first isolated in 1952, there remain significant gaps in knowledge of CHIKV biology, pathogenesis, transmission, and mechanism. Diagnosis is largely simplified and based on symptoms, while treatment is supportive rather than curative. Here we present an overview of the disease, the challenges that lie ahead for future research, and what directions current studies are headed towards, with emphasis on improvement of current animal models and potential use of 3D models.

Chikungunya Virus-Associated Disease

PURPOSE OF REVIEW

Chikungunya virus (CHIKV) infection has become increasingly prevalent in the last decade not only across the southern hemisphere but also, because of a recently documented viral mutation, in southern Europe and the USA. With the global spread of CHIKV infection, practitioners should know its epidemiology, pathophysiology and clinical features.

RECENT FINDINGS

The acute phase of CHIKV disease is characterised by a fever-arthralgia-rash syndrome. Chronic rheumatic manifestations can persist for months to years with very variable clinical presentations. Some cases mimic inflammatory rheumatism such as rheumatoid arthritis. Several risk factors for persistent joint pain, notably older age, have been identified in cohort studies. Despite a low mortality rate with CHIKV infection, the rate of disability with chronic joint symptoms is high, and effective treatments are lacking. Current research is focusing on the development of vaccines and antiviral drugs, and data on treatment of CHIKV-induced chronic arthritis are needed.

Chikungunya Virus-Induced Arthritis: Role of Host and Viral Factors in the Pathogenesis

Chikungunya virus (CHIKV), a member of Alphavirus genus, is responsible for chikungunya fever (CHIKF), which is characterized by the presence of fever, rash, myalgia, and arthralgia. Reemergence of CHIKV has become a significant public health concern in Asian and African countries and is newly emerging in the Middle East, Pacific, American, and European countries. Cytokines, innate (monocytes, natural killer cells) and adaptive immune response (role of B cells and T cells i.e. CD4⁺ and CD8⁺), and/or viral factors contribute to CHIKV-induced arthritis. Vector factors such as vector competence (that includes extrinsic and intrinsic factors) and effect of genome mutations on viral replication and fitness in mosquitoes are responsible for the spread of virus, although they are not directly responsible for CHIKV-induced arthritis. CHIKV-induced arthritis mimics arthritis by involving joints and a common pattern of leukocyte infiltrate, cytokine production, and complement activation. Successful establishment of CHIKV infection and induction of arthritis depends on its ability to manipulate host cellular processes or host factors. CHIKV-induced joint damage is due to host inflammatory response mediated by macrophages, T cells, and antibodies, as well as the possible persistence of the virus in hidden sites. This review provides insight into mechanisms of CHIKV-induced arthritis. Understanding the pathogenesis of CHIKV-induced arthritis will help in developing novel strategies to predict and prevent the disease in virus-infected subjects and combat the disease, thereby decreasing the worldwide burden of the disease.

Management of chikungunya arthritis

Chikungunya fever (CHIKF) is an emerging viral infection that has spread widely, along with its Aedes vectors, throughout the tropics and beyond, causing explosive epidemics of both acute illness and persistent disabling arthritis. There is an urgent need to mitigate the devastating impact of this illness, through vector control, personal protection, and possibly vaccine development. There is also a need to improve treatment for both acute illness and chronic arthritis. In this review, we will review the emergence of CHIK, what is known about pathogenesis and clinical manifestations, and then focus on current understanding of how to treat individual patients, in particular, those who develop chronic arthritis.

Recommendations of the Brazilian Society of Rheumatology for diagnosis and treatment of Chikungunya fever. Part 1 - Diagnosis and special situations

Chikungunya fever has become a relevant public health problem in countries where epidemics occur. Until 2013, only imported cases occurred in the Americas, but in October of that year, the first cases were reported in Saint Marin island in the Caribbean. The first autochthonous cases were confirmed in Brazil in September 2014; until epidemiological week 37 of 2016, 236,287 probable cases of infection with Chikungunya virus had been registered, 116,523 of which had serological confirmation. Environmental changes caused by humans, disorderly urban growth and an ever-increasing number of international travelers were described as the factors responsible for the emergence of large-scale epidemics. Clinically characterized by fever and joint pain in the acute stage, approximately half of patients progress to the chronic stage (beyond 3 months), which is accompanied by persistent and disabling pain. The aim of the present study was to formulate recommendations for the diagnosis and treatment of Chikungunya fever in Brazil. A literature review was performed in the MEDLINE, SciELO and PubMed databases to ground the decisions for recommendations. The degree of concordance among experts was established through the Delphi method, involving 2 in-person meetings and several online voting rounds. In total, 25 recommendations were formulated and divided into 3 thematic groups: (1) clinical, laboratory and imaging diagnosis; (2) special situations; and (3) treatment. The first 2 themes are presented in part 1, and treatment is presented in part 2.

Chikungunya Infection: a Global Public Health Menace

Chikungunya virus (CHIKV) has been involved in epidemics in African and Asian subcontinents and, of late, has transcended to affect the Americas. Aedes aegypti and Aedes albopictus are the major vectors for CHIKV infection, which results in dissemination of virus to various vital organs. Entry of virus into these tissues causes infiltration of innate immune cells, monocytes, macrophages, neutrophils, natural killer cells, and adaptive immune cells. Macrophages bearing the replicating virus, in turn, secrete pro-inflammatory cytokines IL-1β, TNF-α, and IL-17. Together, this pro-inflammatory milieu induces osteoclastogenesis, bone loss, and erosion. CHIKV is characterized by fever, headache, myalgia, rash, and symmetric polyarthritis, which is generally self-limiting. In a subset of cases, however, musculoskeletal symptoms may persist for up to 3-5 years. Viral culture and isolation from blood cells of infected patients are the gold standards for diagnosis of CHIKV. In routine practice, however, assays for anti-CHIKV IgM antibodies are used for diagnosis, as elevated levels in blood of infected patients are noted from 10 days following infection for up to 3-6 months. Early diagnosis of CHIKV is possible by nucleic acid detection techniques. Treatment of acute CHIKV is mainly symptomatic, with analgesics, non-steroidal anti-inflammatory agents (NSAIDs), and low-dose steroids. No vaccines or anti-viral medicines have been approved for clinical therapy in CHIKV as yet. Hydroxychloroquine and methotrexate have been used in chronic CHIKV infection with variable success.

Immunopathology of Chikungunya Virus Infection: Lessons Learned from Patients and Animal Models

Chikungunya virus (CHIKV) is an arthropod-borne alphavirus that causes acute and chronic arthritis. The virus reemerged in the Indian Ocean islands in 2005-2006 and is responsible for outbreaks in the Caribbean islands and the Americas since late 2013. Despite the wealth of research over the past 10 years, there are no commercially available antiviral drugs or vaccines. Treatment usually involves analgesics, anti-inflammatory drugs, and supportive care. Most studies have been focused on understanding the pathogenesis of CHIKV infection through clinical observation and with animal models. In this review, the clinical manifestations of CHIKV that define the disease and the use of relevant animal models, from mice to nonhuman primates, are discussed. Understanding key cellular factors in CHIKV infection and the interplay with the immune system will aid in the development of preventive and therapeutic approaches to combat this painful viral disease in humans.

Chikungunya Virus Disease: An Emerging Challenge for the Rheumatologist

Chikungunya is caused by an alphavirus that is transmitted to humans via the Aedes species mosquito. Chikungunya is endemic to tropical Africa and South and Southeast Asia, but over the past decade, the geographic distribution of the virus has been expanding rapidly. The disease is characterized by fever and severe polyarthritis, and although symptoms typically resolve within 7 to 10 days, some patients experience persistent arthritis and arthralgias for months to years.In December 2013, the first local transmission of chikungunya virus in the Americas was identified in the Caribbean Island of Saint Martin. Since then, the number of afflicted individuals has spread throughout the Caribbean and Central America, as well as into South America. The United States reported 2788 chikungunya virus disease cases among travelers returning from affected areas in 2014. In addition, 11 locally acquired cases were reported in Florida. Further spread and establishment of the disease in the Americas are likely considering the high levels of viremia in infected individuals, widespread distribution of effective vectors, lack of immunity among people living in the Americas, and the popularity of international travel.Considering the prominent rheumatic manifestations of chikungunya, rheumatologists are likely to encounter patients with the disease in their practice. We recommend that rheumatologists consider chikungunya in their differential diagnosis when evaluating patients presenting with fever and joint pain following travel to a chikungunya endemic area. Early diagnosis would ensure timely management and reduction of polypharmacy and its associated complications. In this article, we briefly describe the epidemiology of chikungunya, the clinical features, laboratory testing, prevention, and treatment of disease.

Persistent arthralgia and related risks factors in laboratory-confirmed cases of Chikungunya virus infection in Mexico

Objective.

To estimate the cumulative incidence of persistent arthralgia at 6 months from acute Chikungunya virus (CHIKV) infection and to evaluate the association of clinical markers with the risk of long-term arthralgia.

Methods.

This multicenter retrospective cohort study was conducted in the Mexican state of Colima. A total of 136 individuals aged 15 years and older with serologically confirmed CHIKV infection were enrolled. Participants were interviewed at 6 months from the onset of symptoms, and self-reported persistent arthralgia (PA) was the main binary outcome. A self-report numeric rating scale (NRS) ranging from 0 to 10 was used to estimate the severity of articular pain.

Results.

The cumulative incidence of PA was 41.9%. Severe pain (NRS ≥ 7) presented in 36.8% of participants with PA. In multiple analysis, individuals aged 40 years and older (risk ratio (RR) = 1.60; 95% confidence interval (CI), 1.03-2.48) and those with articular pain at 3 months post-infection (RR = 3.95; 95% CI, 1.95-8.01) had a significantly increased risk of PA at 6 months from CHIKV infection.

Conclusions.

To the best of our knowledge, this is first report of a CHIKV-associated longterm outcome in Mexico, where the incidence of the infection has been high. This is also the first study in Latin America evaluating several factors associated with the risk of PA. Our findings may be useful in health care settings to stratify the risk of chronic arthralgia secondary to CHIKV infection and to identify patients who would benefit clinically from early medical intervention.

Chikungunya virus: epidemiology, replication, disease mechanisms, and prospective intervention strategies

Chikungunya virus (CHIKV), a reemerging arbovirus, causes a crippling musculoskeletal inflammatory disease in humans characterized by fever, polyarthralgia, myalgia, rash, and headache. CHIKV is transmitted by Aedes species of mosquitoes and is capable of an epidemic, urban transmission cycle with high rates of infection. Since 2004, CHIKV has spread to new areas, causing disease on a global scale, and the potential for CHIKV epidemics remains high. Although CHIKV has caused millions of cases of disease and significant economic burden in affected areas, no licensed vaccines or antiviral therapies are available. In this Review, we describe CHIKV epidemiology, replication cycle, pathogenesis and host immune responses, and prospects for effective vaccines and highlight important questions for future research.

Ultrasound of ankles in the diagnosis of complications of chikungunya fever

Objective

To describe the main ultrasound findings of chikungunya fever in the ankle.

Materials and Methods

This was a cross-sectional observational study involving 52 patients referred to the Hospital Universitário Pedro Ernesto and presenting with clinical and biochemical evidence of chikungunya fever. The examinations were performed by a radiologist with more than 20 years of experience in ultrasound.

Results

The predominant gender was female (in 88.5%), and the mean age was 58.4 years. The majority (61.5%) of the patients came from the northern part of the city of Rio de Janeiro, and 46.2% were using corticosteroids to treat inflammatory symptoms. The most common alterations observed by ultrasound were joint effusion (in 69.2%), tenosynovitis (in 59.6%), cellulitis (in 46.2%), Kager's fat pad thickening (in 29.9%), myositis (of the soleus or flexor hallucis longus muscle) (in 17.3%), retrocalcaneal bursitis (in 5.8%), tendon ruptures (in 3.8%), and increased vascular flow on power Doppler (in 3.8%).

Conclusion

Signs of synovitis and tenosynovitis were the main ultrasound findings in a predominantly female population with a mean age of 58.4 years. Further studies are needed in order to define the role of ultrasound in the follow-up of such patients.

A Review of Chikungunya Virus-induced Arthralgia: Clinical Manifestations, Therapeutics, and Pathogenesis

Background:

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that circulates predominantly in tropical and subtropical regions, potentially affecting over 1 billion people. Recently, an outbreak began in the western hemisphere and has resulted in over 1.8 million reported suspected cases. Infection often results in severe fever, rash and debilitating polyarthralgia lasting weeks to months. Additionally, the current literature reports that CHIKV can result in a severe chronic arthralgia and/or arthritis that can last months to years following the initial infection.

Objective:

The purpose of this review is to evaluate the literature and summarize the current state of knowledge regarding CHIKV-associated disease, including clinical presentation, diagnosis, risk factors for development of severe disease, treatment, and pathogenesis in human patients. Additionally, recommendations are presented regarding avenues for clinical research to help further elucidate the pathogenesis of joint disease associated with CHIKV infection.

Conclusion:

While there is an association between initial CHIKV infection and acute disease, a causal relationship with development of chronic arthralgia has not been established at this time. Potential causes of chronic CHIKV-induced arthritis have been postulated, including viral persistence, induction of autoimmune disease, and exacerbation of pre-existing joint disease. While there are numerous reports of chronic CHIKV-associated arthralgia and/or arthritis, there is currently no evidence of a definitive link between initial infection and development of chronic disease. Additional, prospective clinical research on CHIKV-associated disease is necessary to further determine the potential role of virus and development of chronic joint disease.

Efficacy of combination DMARD therapy vs. hydroxychloroquine monotherapy in chronic persistent chikungunya arthritis: a 24-week randomized controlled open label study

In a proportion of patients, chikungunya arthritis (CA) might run into a chronic persistent phase. The treatment for this phase is not very clear. In this randomized parallel group open label study of 24 weeks duration, we evaluated the efficacy of DMARD combination in persistent CA. Consecutive 139 patients with persistent CA (persistent arthritis for >1 year after the chikungunya fever either in 2008 or 2009 fulfilling epidemiological criteria for CA) were screened. Of these patients who were already taking hydroxychloroquine (HCQ) and had active arthritis were randomized to receive either fixed-dose combination therapy (methotrexate 15 mg/day, sulfasalazine 1 g/day, and HCQ 400 mg/day) or continue with HCQ 400 mg/day (dose optimized) monotherapy. Both groups received oral prednisolone up to 6 weeks. Assessments at every 4 weeks were carried out for primary efficacy (disease activity score; DAS ESR 28) and secondary efficacies, HAQ-Indian version and pain VAS100mm. Seventy-two patients were randomized (37 combination therapy, 35 monotherapy). Both groups were well matched in all respects. At 24 weeks, the combination therapy group showed significant improvement in both disease activity (mean ± SD DAS28; 3.39 ± 0.87 vs. 4.74 ± 0.65, p < 0.0001) and disability (mean ± SD HAQ; 1.4 ± 0.31 vs. 1.88 ± 0.47, p < 0.0001). At the study end, pain VAS was significantly less in the combination therapy group (46 ± 6.13 vs. 60.8 ± 11.6, p < 0.0001). Three patients withdrew from the combination group (inefficacy; 2, adverse event; 1) and seven from monotherapy (inefficacy; 7). This study provide evidence that for chronic persistent CA combination DMARD therapy with methotrexate, sulfasalazine and HCQ is superior to monotherapy with HCQ.

Rheumatology in India: a Bird's Eye View on Organization, Epidemiology, Training Programs and Publications

India is home to the world's second largest population. Rheumatology is an emerging specialty in India. We reviewed organization, epidemiology and training facilities for Rheumatology in India. Also, we also looked at publications in the field of rheumatology from India from over the past six years using Scopus and Medline databases. Despite rheumatologic disorders affecting 6%-24% of the population, rheumatology in India is still in its infancy. Till recently, there were as few as two centers in the country training less than five fellows per year. However, acute shortage of specialists and increasing patient numbers led to heightened awareness regarding the need to train rheumatologists. Subsequently, six new centers have now started 3-year training programs in rheumatology. The epidemiology of rheumatic diseases in India is being actively studies under the Community Oriented Programme for Control of Rheumatic Diseases (COPCORD) initiative. The most number of publications on rheumatic diseases from India are on rheumatoid arthritis, lupus and osteoporosis, many of which have been widely cited. Major collaborators worldwide are USA, UK and France, whereas those from Asia are Japan, Saudi Arabia and Singapore. The Indian Rheumatology Association (IRA) is the national organization of rheumatologists. The flagship publication of the IRA, the Indian Journal of Rheumatology, is indexed in Scopus and Embase. To conclude, rheumatology in India is an actively expanding and productive field with significant contributions to world literature. There is a need to train more personnel in the subject in India.

Novel Lesions of Bones and Joints Associated with Chikungunya Virus Infection in Two Mouse Models of Disease: New Insights into Disease Pathogenesis

Chikungunya virus is an arbovirus spread predominantly by Aedes aegypti and Ae. albopictus mosquitoes, and causes debilitating arthralgia and arthritis. While these are common manifestations during acute infection and it has been suggested they can recur in patients chronically, gaps in knowledge regarding the pathogenesis still exist. Two established mouse models were utilized (adult IRF 3/7 -/- -/- and wild-type C57BL/6J mice) to evaluate disease manifestations in bones and joints at various timepoints. Novel lesions in C57BL/6J mice consisted of periostitis (91%) and foci of cartilage of necrosis (50% of mice at 21 DPI). Additionally, at 21 DPI, 50% and 75% of mice exhibited periosteal bone proliferation affecting the metatarsal bones, apparent via histology and μCT, respectively. μCT analysis did not reveal any alterations in trabecular bone volume measurements in C57BL/6J mice. Novel lesions demonstrated in IRF 3/7 -/- -/- mice at 5 DPI included focal regions of cartilage necrosis (20%), periosteal necrosis (66%), and multifocal ischemic bone marrow necrosis (100%). Contralateral feet in 100% of mice of both strains had similar, though milder lesions. Additionally, comparison of control IRF 3/7 -/- -/- and wild-type C57BL/6J mice demonstrated differences in cortical bone. These experiments demonstrate novel manifestations of disease similar to those occurring in humans, adding insight into disease pathogenesis, and representing new potential targets for therapeutic interventions. Additionally, results demonstrate the utility of μCT in studies of bone and joint pathology and illustrate differences in bone dynamics between mouse strains.

Chikungunya virus pathogenesis and immunity

Chikungunya virus (CHIKV) is an arbovirus associated with acute and chronic arthralgia that re-emerged in the Indian Ocean islands in 2005-2006 and is currently responsible for the ongoing outbreaks in the Caribbean islands and the Americas. We describe here the acute and chronic clinical manifestations of CHIKV in patients that define the disease. We also review the various animal models that have been developed to study CHIKV infection and pathology and further strengthened the understanding of the cellular and molecular mechanisms of CHIKV infection and immunity. A complete understanding of the immunopathogenesis of CHIKV infection will help develop the needed preventive and therapeutic approaches to combat this arbovirosis.

The pathogenesis of chronic chikungunya: evolving concepts

Chikungunya virus (CHIKV) re-emerged and caused an outbreak in the Caribbean and the Americas. CHIKV can cause incapacitating arthralgia, which may be evolved in chronic arthritis that is similar to rheumatoid arthritis that lasts for months or years. This review provides an overview of known and hypothesized mechanisms that CHIKV uses to promote chronic arthritis. We hypothesized that the chronic inflammatory response that is stimulated by persisting CHIKV replication in the joints results in the arthritic symptoms seen in patients. Most hypotheses proposed in this review need to be tested or confirmed, which may help in the development of new specific treatments and vaccines against CHIKV that will not only combat viral persistence but also prevent tissue damage.

Chikungunya: bending over the Americas and the rest of the world

Chikungunya is an arthropod-borne virus transmitted by Aedes mosquito bites. A viral mutation has allowed Aedes albopictus to become the preferred vector extending the geographic spread of the condition. The virus causes an acute febrile illness occasionally followed by a chronic rheumatic condition causing severe impairment. The diagnosis is usually confirmed with serology. No specific treatment is currently available. This article reviews the condition with emphasis on his dissemination in the Americas.

Diagnóstico diferencial de dengue y chikungunya en pacientes pediátricos

<p><strong>Introducción.</strong> Las infecciones por el virus del dengue y del chikungunya presentan síntomas clínicos similares, lo cual dificulta el diagnóstico clínico. Además, son transmitidas por los mismos vectores, por lo que en una región puede haber circulación e infección simultánea con los dos virus. Los resultados de cada enfermedad, no obstante, son diferentes: la fiebre del chikungunya rara vez es fatal, pero puede dejar secuelas de tipo articular y neurológico, en tanto que el dengue es potencialmente fatal. De ahí la importancia de un diagnóstico preciso y oportuno.<br /><strong>Objetivo.</strong> Comparar el diagnóstico presuntivo basado en los hallazgos clínicos con el diagnóstico diferencial hecho mediante pruebas de laboratorio.<br /><strong>Materiales y métodos.</strong> Se utilizaron pruebas virológicas y serológicas específicas para dengue y chikungunya en ocho muestras de sangre de pacientes pediátricos con síndrome febril. Se empleó la reacción en cadena de la polimerasa con transcriptasa inversa para detectar los virus del dengue y del chikungunya y el método de ELISA basado en la captura de IgM para confirmar los casos de dengue.<br /><strong>Resultados.</strong> Con base en los hallazgos clínicos, dos pacientes se clasificaron como casos probables de dengue o chikungunya, dos como casos probables de chikungunya y en cuatro no hubo diagnóstico presuntivo de infección viral. Las pruebas de laboratorio confirmaron la infección por el virus del dengue en dos pacientes, por el virus del chikungunya en otros dos e infección simultánea de dengue y chikungunya en los cuatro restantes.<br /><strong>Conclusión.</strong> Los hallazgos clínicos no fueron suficientes para hacer un diagnóstico en pacientes pediátricos con síndrome febril, por lo cual se requirieron pruebas específicas de laboratorio para establecer con precisión el agente etiológico causante de la enfermedad.</p><p> </p>

Long-Term Arthralgia after Mayaro Virus Infection Correlates with Sustained Pro-inflammatory Cytokine Response

Mayaro virus (MAYV), an alphavirus similar to chikungunya virus (CHIKV), causes an acute debilitating disease which results in the development of long-term arthralgia in more than 50% of infected individuals. Currently, the immune response and its role in the development of MAYV-induced persistent arthralgia remain unknown. In this study, we evaluated the immune response of individuals with confirmed MAYV infection in a one-year longitudinal study carried out in Loreto, Peru. We report that MAYV infection elicits robust immune responses that result in the development of a strong neutralizing antibody response and the secretion of pro-inflammatory immune mediators. The composition of these inflammatory mediators, in some cases, differed to those previously observed for CHIKV. Key mediators such as IL-13, IL-7 and VEGF were strongly induced following MAYV infection and were significantly increased in subjects that eventually developed persistent arthralgia. Although a strong neutralizing antibody response was observed in all subjects, it was not sufficient to prevent the long-term outcomes of MAYV infection. This study provides initial immunologic insight that may eventually contribute to prognostic tools and therapeutic treatments against this emerging pathogen.

Mayaro virus (MAYV) causes an acute debilitating disease which results in the development of long-term arthralgia in more than 50% of infected individuals, similarly to what has been described with CHIKV. In this study, we evaluated the immune response of individuals with confirmed MAYV infection in a one-year longitudinal study carried out in Loreto, Peru. Here, we report that MAYV infection elicits robust immune responses that result in the development of a strong neutralizing antibody response and the secretion of pro-inflammatory immune mediators. These inflammatory mediators, in some cases, differed to those observed by others for CHIKV. We also observed a strong neutralizing antibody response in all the study subjects; however, this response was not sufficient to prevent the long-term outcomes of MAYV infection. Taken together, this study provides initial immunologic insight that may eventually contribute to the development of prognostic tools and potential therapeutic treatments against this emerging pathogen.

Imported chikungunya fever in Madrid

Chikungunya Fever is a mosquito-transmitted viral disease that causes fever, rash and musculoskeletal complaints. The latest may persist for several months, or even years or developed a relapsing course, that deserve an adequate treatment. Due to the large outbreak declared in the Caribbean in 2013, imported cases of Chikungunya as well as the risk of autochthonous transmission in case of available vectors have increased in non-endemic countries, like Spain. We described four cases of Chikungunya treated in our clinic.