Chikungunya arthritis

Expression of scFv-anti-CHIKV-E2 in Escherichia coli with chaperones Co-expression, and its functional assay by electrochemical immunosensor

Single Chain Variable Fragment (scFv), a small fragment of antibody can be used to substitute the monoclonal antibody for diagnostic purposes. Production of scFv in Escherichia coli host has been a challenge due to the potential miss-folding and formation of inclusion bodies. This study aimed to express anti-CHIKV E2 scFv which previously designed specifically for Asian strains by co-expression of three chaperones that play a role in increasing protein solubility; GroEL, GroES, and Trigger Factor. The scFv and chaperones were expressed in Origami B E. coli host under the control of the T7 promoter, and purified using a Ni-NTA column. Functional assay of anti-CHIKV-E2 scFv was examined by electrochemical immunosensor using gold modified Screen Printed Carbon Electrode (SPCE), and characterized by differential pulses voltammetry (DPV) using K3[Fe(CN)6] redox system and scanning microscope electron (SEM). The experimental condition was optimized using the Box-Behnken design. The results showed that co-expression of chaperone increased the soluble scFv yield from 54.405 μg/mL to 220.097 µg/mL (~5×). Furthermore, scFv can be used to detect CHIKV-E2 in immunosensor electrochemistry with a detection limit of 0.74048 ng/mL and a quantification limit of 2,24388 ng/mL. Thus, the scFv-anti-CHIKV-E2 can be applied as a bioreceptor in another immunoassay method.

Conjugates of ibuprofen inhibit CHIKV infection and inflammation

Chikungunya virus infection has become a global health concern because of its high rates of morbidity and mortality in patients with preexisting conditions. Inflammation and arthritis are the major symptoms of CHIKV that persist even after clearance of CHIKV. To develop an antiviral that can reduce infection and manage inflammation independent of the CHIKV infection, ibuprofen (IBU) conjugates with sulfonamide and thiosemicarbazide were synthesized. The conjugates, IBU-SULFA, IBU-ISS and IBU-IBT significantly inhibited CHIKV infection in vitro with a selectivity index (CC50/IC50) of > 11.9, > 25.1 and > 21, respectively. The reduction in infection was attributed to the interference of the conjugates in the early stages of CHIKV life cycle. With no acute oral toxicity, these compounds significantly reduced inflammation and arthritis in rats. Unlike IBU, the conjugates were not ulcerogenic. In conclusion, the conjugation imparted anti-CHIKV properties while retaining the anti-inflammatory properties of IBU. These findings can encourage further validation and research to develop an antiviral for CHIKV to manage both infection and arthritis.

Immunogenicity, safety and duration of protection afforded by chikungunya virus vaccines undergoing human clinical trials

Background. Chikungunya virus (CHIKV) causes chikungunya fever and has been responsible for major global epidemics of arthritic disease over the past two decades. Multiple CHIKV vaccine candidates are currently undergoing or have undergone human clinical trials, with one vaccine candidate receiving FDA approval. This scoping review was performed to evaluate the 'efficacy', 'safety' and 'duration of protection' provided by CHIKV vaccine candidates in human clinical trials.Methods. This scoping literature review addresses studies involving CHIKV vaccine clinical trials using available literature on the PubMed, Medline Embase, Cochrane Library and Clinicaltrial.gov databases published up to 25 August 2023. Covidence software was used to structure information and review the studies included in this article.Results. A total of 1138 studies were screened and, after removal of duplicate studies, 12 relevant studies were thoroughly reviewed to gather information. This review summarizs that all seven CHIKV vaccine candidates achieved over 90 % seroprotection against CHIKV after one or two doses. All vaccines were able to provide neutralizing antibody protection for at least 28 days.Conclusions. A variety of vaccine technologies have been used to develop CHIKV vaccine candidates. With one vaccine candidate having recently received FDA approval, it is likely that further CHIKV vaccines will be available commercially in the near future.

Longitudinal analysis of post-acute chikungunya-associated arthralgia in children and adults: A prospective cohort study in Managua, Nicaragua (2014-2018)

Chikungunya can result in debilitating arthralgia, often presenting as acute, self-limited pain, but occasionally manifesting chronically. Little is known about differences in chikungunya-associated arthralgia comparing children to adults over time. To characterize long-term chikungunya-associated arthralgia, we recruited 770 patients (105 0-4 years old [y/o], 200 5-9 y/o, 307 10-15 y/o, and 158 16+ y/o) with symptomatic chikungunya virus infections in Managua, Nicaragua, during two consecutive chikungunya epidemics (2014-2015). Participants were assessed at ~15 days and 1, 3, 6, 12, and 18 months post-fever onset. Following clinical guidelines, we defined participants by their last reported instance of arthralgia as acute (≤10 days post-fever onset), interim (>10 and <90 days), or chronic (≥90 days) cases. We observed a high prevalence of arthralgia (80-95%) across all ages over the study period. Overall, the odds of acute arthralgia increased in an age-dependent manner, with the lowest odds of arthralgia in the 0-4 y/o group (odds ratio [OR]: 0.27, 95% confidence interval [CI]: 0.14-0.51) and the highest odds of arthralgia in the 16+ y/o participants (OR: 4.91, 95% CI: 1.42-30.95) relative to 10-15 y/o participants. Females had higher odds of acute arthralgia than males (OR: 1.63, 95% CI: 1.01-2.65) across all ages. We found that 23-36% of pediatric and 53% of adult participants reported an instance of post-acute arthralgia. Children exhibited the highest prevalence of post-acute polyarthralgia in their legs, followed by the hands and torso - a pattern not seen among adult participants. Further, we observed pediatric chikungunya presenting in two distinct phases: the acute phase and the subsequent interim/chronic phases. Thus, differences in the presentation of arthralgia were observed across age, sex, and disease phase in this longitudinal chikungunya cohort. Our results elucidate the long-term burden of chikungunya-associated arthralgia among pediatric and adult populations.

The impact of arthritogenic viruses in oral tissues

Arthritis and periodontitis are inflammatory diseases that share several immunopathogenic features. The expansion in the study of virus-induced arthritis has shed light on how this condition could impact other parts of the human body, including the mouth. Viral arthritis is an inflammatory joint disease caused by several viruses, most notably the alphaviruses Chikungunya virus (CHIKV), Sindbis virus (SINV), Ross River virus (RRV), Mayaro virus (MAYV), and O'nyong'nyong virus (ONNV). These viruses can induce an upsurge of matrix metalloproteinases and immune-inflammatory mediators such as Interleukin-6 (IL6), IL-1β, tumor necrosis factor, chemokine ligand 2, and receptor activator of nuclear factor kappa-B ligand in the joint and serum of infected individuals. This can lead to the influx of inflammatory cells to the joints and associated muscles as well as osteoclast activation and differentiation, culminating in clinical signs of swelling, pain, and bone resorption. Moreover, several data indicate that these viral infections can affect other sites of the body, including the mouth. The human oral cavity is a rich and diverse microbial ecosystem, and viral infection can disrupt the balance of microbial species, causing local dysbiosis. Such events can result in oral mucosal damage and gingival bleeding, which are indicative of periodontitis. Additionally, infection by RRV, CHIKV, SINV, MAYV, or ONNV can trigger the formation of osteoclasts and upregulate pro-osteoclastogenic inflammatory mediators, interfering with osteoclast activation. As a result, these viruses may be linked to systemic conditions, including oral manifestations. Therefore, this review focuses on the involvement of alphavirus infections in joint and oral health, acting as potential agents associated with oral mucosal inflammation and alveolar bone loss. The findings of this review demonstrate how alphavirus infections could be linked to the comorbidity between arthritis and periodontitis and may provide a better understanding of potential therapeutic management for both conditions.

Salicylic Acid Conjugate of Telmisartan Inhibits Chikungunya Virus Infection and Inflammation

There is no approved antiviral for the management of the Chikungunya virus (CHIKV). To develop an antiviral drug that can manage both CHIKV and arthritis induced by it, an ester conjugate of telmisartan (TM) and salicylic acid (SA) was synthesized (DDABT1). It showed higher potency (IC50 of 14.53 μM) and a good selectivity index [(SI = CC50/IC50) > 33]. On post-treatment of DDABT1, CHIKV infection was inhibited significantly by reducing CPE, viral titer, viral RNA, and viral proteins. Further, the time of addition experiment revealed >95% inhibition up to 4hpi indicating its interference predominantly in the early stages of infection. However, the late stages were also affected. This conjugate of SA and TM was found to increase the antiviral efficacy, and this might be partly attributed to modulating angiotensin II (Ang II) receptor type 1 (AT1). However, DDABT1 might have other modes of action that need further investigation. In addition, the in vivo experiments showed an LD50 of 5000 mg/kg in rats and was found to be more effective than TM, SA, or their combination against acute, subacute, and chronic inflammation/arthritis in vivo. In conclusion, DDABT1 showed remarkable anti-CHIKV properties and the ability to reduce inflammation and arthritis, making it a very good potential drug candidate that needs further experimental validation.

Predictors of chronic joint pain after Chikungunya virus infection in the INOVACHIK prospective cohort study

BACKGROUND

Chikungunya can cause persistent chronic joint pain. Knowledge of the risk factors for disease progression is important for preventing and controlling complications. This study aimed to identify factors associated with chronic joint pain.

METHODS

This prospective cohort study was conducted at a reference center in Rio de Janeiro. Men and women (aged ≥ 18 years) in the acute phase of Chikungunya were included. Clinical data and samples were collected over three months. Risk factors were evaluated using multivariate and logistic regression analyses.

RESULTS

A total of 107 patients were followed up. The incidence rate of joint tenderness was 61.7 %. Female sex (adjusted odds ratio [AOR] 3.24, 95 % confidence interval [CI]:1.07-9.77), diarrhea (AOR 5.08, 95 % CI:1.55-16.67), severe joint pain (AOR 4.26, 95 % CI:1.06-17.06), and CHIKV real-time reverse transcription polymerase chain reaction positivity up to 5 days after the onset of symptoms in urine or saliva (AOR 4.56, 95 % CI:1.41-14.77) were identified as predictors of persistent chronic pain.

CONCLUSIONS

In a predominantly female population, musculoskeletal symptoms are not the sole determinant of chronic pain, and careful evaluation of CHIKV detection in alternative body fluids (such as saliva and urine) during the early phase of the disease is warranted.

Chikungunya Virus, Metabolism, and Circadian Rhythmicity Interplay in Phagocytic Cells

Chikungunya virus (CHIKV) is transmitted to humans by mosquitoes of the genus Aedes, causing the chikungunya fever disease, associated with inflammation and severe articular incapacitating pain. There has been a worldwide reemergence of chikungunya and the number of cases increased to 271,006 in 2022 in the Americas alone. The replication of CHIKV takes place in several cell types, including phagocytic cells. Monocytes and macrophages are susceptible to infection by CHIKV; at the same time, they provide protection as components of the innate immune system. However, in host-pathogen interactions, CHIKV might have the ability to alter the function of immune cells, partly by rewiring the tricarboxylic acid cycle. Some viral evasion mechanisms depend on the metabolic reprogramming of immune cells, and the cell metabolism is intertwined with circadian rhythmicity; thus, a circadian immunovirometabolism axis may influence viral pathogenicity. Therefore, analyzing the interplay between viral infection, circadian rhythmicity, and cellular metabolic reprogramming in human macrophages could shed some light on the new field of immunovirometabolism and eventually contribute to the development of novel drugs and therapeutic approaches based on circadian rhythmicity and metabolic reprogramming.

Inflammation, fibrosis and E1 glycoprotein persistence in joint tissue of patients with post-Chikungunya chronic articular disease

INTRODUCTION

Chikungunya chronic joint disease causes debilitating arthralgia, significantly impacting the quality of life of affected individuals.

METHODS

In this study, patients underwent clinical follow-ups, joint biopsies, and pre-biopsy and 24 months post-biopsy serum dosage of cytokines.

RESULTS

All participants were female and had pain in 12 joints on average, with 41.17% exhibiting moderate disease activity. Histopathological analysis revealed collagen deposition. Indirect immunofluorescence detected the CHIKV glycoprotein E1 antigen, and an increase in cytokines.

CONCLUSIONS

Persistent inflammation and ineffective antiviral immune responses leading to antigen persistence may contribute to chronic CHIKV arthritis.

Cognitive impairment in post-acute sequelae of COVID-19 and short duration myalgic encephalomyelitis patients is mediated by orthostatic hemodynamic changes

Introduction

Cognitive impairment is experienced by people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-acute sequelae of COVID-19 (PASC). Patients report difficulty remembering, concentrating, and making decisions. Our objective was to determine whether orthostatic hemodynamic changes were causally linked to cognitive impairment in these diseases.

Methods

This prospective, observational cohort study enrolled PASC, ME/CFS, and healthy controls. All participants underwent clinical evaluation and assessment that included brief cognitive testing before and after an orthostatic challenge. Cognitive testing measured cognitive efficiency which is defined as the speed and accuracy of subject's total correct responses per minute. General linear mixed models were used to analyze hemodynamics and cognitive efficiency during the orthostatic challenge. Additionally, mediation analysis was used to determine if hemodynamic instability induced during the orthostatic challenge mediated the relationship between disease status and cognitive impairment.

Results

Of the 276 participants enrolled, 256 were included in this study (34 PASC, 71 < 4 year duration ME/CFS, 69 > 10 year ME/CFS duration, and 82 healthy controls). Compared to healthy controls, the disease cohorts had significantly lower cognitive efficiency scores immediately following the orthostatic challenge. Cognitive efficiency remained low for the >10 year ME/CFS 2 and 7 days after orthostatic challenge. Narrow pulse pressure less than 25% of systolic pressure occurred at 4 and 5 min into the orthostatic challenge for the PASC and ME/CFS cohorts, respectively. Abnormally narrow pulse pressure was associated with slowed information processing in PASC patients compared to healthy controls (-1.5, p = 0.04). Furthermore, increased heart rate during the orthostatic challenge was associated with a decreased procedural reaction time in PASC and < 4 year ME/CFS patients who were 40 to 65 years of age.

Discussion

For PASC patients, both their disease state and hemodynamic changes during orthostatic challenge were associated with slower reaction time and decreased response accuracy during cognitive testing. Reduced cognitive efficiency in <4 year ME/CFS patients was associated with higher heart rate in response to orthostatic stress. Hemodynamic changes did not correlate with cognitive impairment for >10 year ME/CFS patients, but cognitive impairment remained. These findings underscore the need for early diagnosis to mitigate direct hemodynamic and other physiological effects on symptoms of cognitive impairment.

Longitudinal Analysis of the Burden of Post-Acute Chikungunya-Associated Arthralgia in Children and Adults: A Prospective Cohort Study in Managua, Nicaragua (2014-2019)

Chikungunya can result in debilitating arthralgia, often presenting as acute, self-limited pain, but occasionally manifesting chronically. Little is known about differences in chikungunya-associated arthralgia comparing children to adults over time. To characterize long-term chikungunya-associated arthralgia, we recruited 770 patients (105 0-4 year olds [y/o], 200 5-9 y/o, 307 10-15 y/o, and 158 16+ y/o) with symptomatic chikungunya virus infections in Managua, Nicaragua, during two chikungunya epidemics (2014-2015). Participants were assessed at ~15 days and 1, 3, 6, 12, and 18 months post-fever onset. Following clinical guidelines, we defined participants by their last reported instance of arthralgia as acute (≤10 days post-fever onset), interim (>10 and <90 days), or chronic (≥90 days) cases. We observed a high prevalence of arthralgia (80-95%) across all ages over the study period. Overall, the odds of acute arthralgia increased in an age-dependent manner, with the lowest odds of arthralgia in the 0-4 y/o group (odds ratio [OR]: 0.27, 95% confidence interval [CI]: 0.14-0.51) and the highest odds of arthralgia in the 16+ y/o participants (OR: 4.91, 95% CI: 1.42-30.95) relative to 10-15 y/o participants. Females had a higher odds of acute arthralgia than males (OR: 1.63, 95% CI: 1.01-2.65) across all ages. We found that 23-36% of pediatric and 53% of adult participants reported an instance of post-acute arthralgia. Children exhibited the highest prevalence of post-acute polyarthralgia in their legs, followed by the hands and torso - a pattern not seen among adult participants. Further, we observed pediatric chikungunya presenting in two distinct phases: the acute phase and the associated interim and chronic phases. Differences in the presentation of arthralgia were observed across age, sex, and disease phase in this longitudinal chikungunya cohort. Our results elucidate the long-term burden of chikungunya-associated arthralgia among pediatric and adult populations.

Chikungunya fever

Chikungunya virus is widespread throughout the tropics, where it causes recurrent outbreaks of chikungunya fever. In recent years, outbreaks have afflicted populations in East and Central Africa, South America and Southeast Asia. The virus is transmitted by Aedes aegypti and Aedes albopictus mosquitoes. Chikungunya fever is characterized by severe arthralgia and myalgia that can persist for years and have considerable detrimental effects on health, quality of life and economic productivity. The effects of climate change as well as increased globalization of commerce and travel have led to growth of the habitat of Aedes mosquitoes. As a result, increasing numbers of people will be at risk of chikungunya fever in the coming years. In the absence of specific antiviral treatments and with vaccines still in development, surveillance and vector control are essential to suppress re-emergence and epidemics.

Post-exertional malaise among people with long COVID compared to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

BACKGROUND

Long COVID describes a condition with symptoms that linger for months to years following acute COVID-19. Many of these Long COVID symptoms are like those experienced by patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

OBJECTIVE

We wanted to determine if people with Long COVID experienced post-exertional malaise (PEM), the hallmark symptom of ME/CFS, and if so, how it compared to PEM experienced by patients with ME/CFS.

METHODS

A questionnaire that asked about the domains of PEM including triggers, experience, recovery, and prevention was administered to 80 people seeking care for Long COVID at Bateman Horne Center. Their responses were compared to responses about PEM given by 151 patients with ME/CFS using chi-square tests of independence.

RESULTS

All but one Long COVID respondent reported having PEM. There were many significant differences in the types of PEM triggers, symptoms experienced during PEM, and ways to recover and prevent PEM between Long COVID and ME/CFS. Similarities between Long COVID and ME/CFS included low and medium physical and cognitive exertion to trigger PEM, symptoms of fatigue, pain, immune reaction, neurologic, orthostatic intolerance, and gastrointestinal symptoms during PEM, rest to recover from PEM, and pacing to prevent PEM.

CONCLUSION

People with Long COVID experience PEM. There were significant differences in PEM experienced by people with Long COVID compared to patients with ME/CFS. This may be due to the newness of Long COVID, not knowing what exertional intolerance is or how to manage it.

Development of a Novel Chikungunya Virus-Like Replicon Particle for Rapid Quantification and Screening of Neutralizing Antibodies and Antivirals

Chikungunya fever is a mosquito-transmitted infectious disease that induces rash, myalgia, and persistent incapacitating arthralgia. At present, no vaccines or antiviral therapies specific to Chikungunya virus (CHIKV) infection have been approved, and research is currently restricted to biosafety level 3 containment. CHIKV-like replicon particles (VRPs) are single-cycle infectious particles containing viral structure proteins, as well as a defective genome to provide a safe surrogate for living CHIKV to facilitate the testing of vaccines and antivirals. However, inefficient RNA transfection and the potential emergence of the competent virus through recombination in mammalian cells limit VRP usability. This study describes a transfection-free system for the safe packaging of CHIK VRP with all necessary components via transduction of mosquito cell lines using a single baculovirus vector. We observed the release of substantial quantities of mosquito cell-derived CHIK VRP (mos-CHIK VRP) from baculovirus-transduced mosquito cell lines. The VRPs were shown to recapitulate viral replication and subgenomic dual reporter expression (enhanced green fluorescent protein [eGFP] and luciferase) in infected host cells. Interestingly, the rapid expression kinetics of the VRP-expressing luciferase reporter (6 h) makes it possible to use mos-CHIK VRPs for the rapid quantification of VRP infection. Treatment with antivirals (suramin or 6-azauridine) or neutralizing antibodies (monoclonal antibodies [MAbs] or patient sera) was shown to inhibit mos-CHIK VRP infection in a dose-dependent manner. Ease of manufacture, safety, scalability, and high throughput make mos-CHIK VRPs a highly valuable vehicle for the study of CHIKV biology, the detection of neutralizing (NT) antibody activity, and the screening of antivirals against CHIKV. IMPORTANCE This study proposes a transfection-free system that enables the safe packaging of CHIK VRPs with all necessary components via baculovirus transduction. Those mosquito cell-derived CHIK VRP (mos-CHIK VRPs) were shown to recapitulate viral replication and subgenomic dual reporter (enhanced green fluorescent protein [eGFP] and luciferase) expression in infected host cells. Rapid expression kinetics of the VRP-expressing luciferase reporter (within hours) opens the door to using mos-CHIK VRPs for the rapid quantification of neutralizing antibody and antiviral activity against CHIKV. To the best of our knowledge, this is the first study to report a mosquito cell-derived alphavirus VRP system. Note that this system could also be applied to other arboviruses to model the earliest event in arboviral infection in vertebrates.

Long lasting anti-IgG chikungunya seropositivity in the Mayotte population will not be enough to prevent future outbreaks: A seroprevalence study, 2019

Chikungunya is an arboviral disease causing arthralgia which may develop into a debilitating chronic arthritis. In Mayotte, a French overseas department in the Indian Ocean, a chikungunya outbreak was reported in 2006, affecting a third of the population. We aimed at assessing the chikungunya seroprevalence in this population, after over a decade from that epidemic. A multi-stage cross sectional household-based study exploring socio-demographic factors, and knowledge and attitude towards mosquito-borne disease prevention was carried out in 2019. Blood samples from participants aged 15-69 years were taken for chikungunya IgG serological testing. We analyzed associations between chikungunya serological status and selected factors using Poisson regression models, and estimated weighted and adjusted prevalence ratios (w/a PR). The weighted seroprevalence of chikungunya was 34.75% (n = 2853). Seropositivity for IgG anti-chikungunya virus was found associated with living in Mamoudzou (w/a PR = 1.49, 95%CI: 1.21-1.83) and North (w/a PR = 1.41, 95%CI: 1.08-1.84) sectors, being born in the Comoros islands (w/a PR = 1.30, 95%CI: 1.03-1.61), being a student or unpaid trainee (w/a PR = 1.35, 95%CI: 1.01-1.81), living in precarious housing (w/a PR = 1.30, 95%CI: 1.02-1.67), accessing water streams for bathing (w/a PR = 1.72, 95%CI: 1.1-2.7) and knowing that malaria is a mosquito-borne disease (w/a PR = 1.42, 95%CI: 1.21-1.83). Seropositivity was found inversely associated with high education level (w/a PR = 0.50, 95%CI: 0.29-0.86) and living in households with access to running water and toilets (w/a PR = 0.64, 95%CI: 0.51-0.80) (n = 1438). Our results indicate a long-lasting immunity from chikungunya exposure. However, the current population seroprevalence is not enough to protect from future outbreaks. Individuals naïve to chikungunya and living in precarious socio-economic conditions are likely to be at high risk of infection in future outbreaks. To prevent and prepare for future chikungunya epidemics, it is essential to address socio-economic inequalities as a priority, and to strengthen chikungunya surveillance in Mayotte.

Understanding the Biology and Immune Pathogenesis of Chikungunya Virus Infection for Diagnostic and Vaccine Development

Chikungunya virus, the causative agent of chikungunya fever, is generally characterized by the sudden onset of symptoms, including fever, rash, myalgia, and headache. In some patients, acute chikungunya virus infection progresses to severe and chronic arthralgia that persists for years. Chikungunya infection is more commonly identified in tropical and subtropical regions. However, recent expansions and epidemics in the temperate regions have raised concerns about the future public health impact of chikungunya diseases. Several underlying factors have likely contributed to the recent re-emergence of chikungunya infection, including urbanization, human travel, viral adaptation to mosquito vectors, lack of effective control measures, and the spread of mosquito vectors to new regions. However, the true burden of chikungunya disease is most likely to be underestimated, particularly in developing countries, due to the lack of standard diagnostic assays and clinical manifestations overlapping with those of other endemic viral infections in the regions. Additionally, there have been no chikungunya vaccines available to prevent the infection. Thus, it is important to update our understanding of the immunopathogenesis of chikungunya infection, its clinical manifestations, the diagnosis, and the development of chikungunya vaccines.

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.

A Chikungunya Outbreak in a Dengue-endemic Region in Rural Northern Coastal Ecuador

Dengue virus (DENV) reemerged in the Americas in the 1980s and 1990s, whereas chikungunya virus (CHIKV) emerged in 2014. Although CHIKV produced large epidemics from 2014 to 2017, dengue fever has been the prominent arboviral disease identified through passive surveillance, bringing to question the degree to which cases are misdiagnosed. To address this concern, we conducted an active household-based surveillance of arboviral-like illnesses in six rural and remote communities in northern coastal Ecuador from May 2019 to February 2020. Although passive surveillance conducted by the Ecuadorian Ministry of Health reported only DENV cases in the region, more than 70% of the arbovirus-like illnesses detected by active surveillance in our study were positive for CHIKV. These findings underline the need for active surveillance of arboviral infections with laboratory confirmation, especially in rural communities where arboviral illnesses are more likely to be underreported.

Can hydroxychloroquine be used for COVID-19-induced arthritis? A debatable hypothesis

Hydroxychloroquine (HCQ) is a known disease-modifying antirheumatic drug for rheumatoid arthritis. It is also being used in viral arthritis on many occasions. HCQ is also being used to treat coronavirus disease 2019, but the results are not satisfactory. HCQ has been shown to have antiviral effects. In this context, we have a hypothesis that HCQ may be used as a treatment option in post-coronavirus disease 2019 arthritis.

Role of Arbovirus Infection in Arthritogenic Pain Manifestation—A Systematic Review

The number of publications on the development of arthritic pain after CHIKV infection is increasing; however, there is still a gap in the pathophysiological mechanisms that explain these outcomes. In this review, we conducted a descriptive analysis of the findings of patients to understand their prognosis and to explore therapeutic options. Here, we searched the Cochrane, BVS, PubMed, and Scielo databases using the keywords “arthritis”, “pain”, “arbovirus”, “disease”, “arthritogenic”, and “arthralgia” during the 2000 to 2022 period. Descriptive analyses were conducted to understand the association between CHIKV infection and arthritogenic pain. The present study shows the persistence of acute phase signals for months, making the chronic phase still marked by the presence of arthralgia, often disabling under stimuli, such as temperature variation. CHIKV infection appears to be remarkably similar to rheumatoid arthritis, since both diseases share common symptoms. Once diagnosed, patients are mostly treated with analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and disease modifying anti-rheumatic drugs (DMARD). As there are no prophylactic measures or specific treatments for arboviruses, this study gathered information on the development and manifestations of arthritogenic pain.

In silico design of a multi-epitope Chimera from Aedes aegypti salivary proteins OBP 22 and OBP 10: A promising candidate vaccine

BACKGROUND & OBJECTIVES

The emergence and re-emergence of arboviruses such as dengue, Chikungunya and Zika viruses causing morbidity and mortality around the globe are of serious concern. A safe and effective vaccine is essential to control viral transmission. The salivary proteins of the mosquito that aid in blood probing, feeding and development are immunogenic. We aimed to report a multi-epitope candidate vaccine chimera from Aedes aegyptii mosquito salivary proteins OBP 22 and OBP 10 that could confer protection against all pathogens transmitted by the vector.

METHODS

Linear and conformation B-cell epitopes and MHC class-I and class-II binding T- cell epitopes were predicted using bioinformatic tools. Selected B- and T-cell epitopes were chosen for designing a multiepitope vaccine construct. The chimeric construct was analyzed for its immunogenicity, TAP and proteasomal cleavage, allergenicity, and structural validation for its suitability to be used as a candidate vaccine. Molecular docking was carried out to analyze the binding interactions with TLRs molecules.

RESULTS

A chimeric multiepitope vaccine was designed with the best-selected combination of immunogenic B-cell epitope, cytotoxic and helper T-cell and gamma interferon inducing epitopes with suitable adjuvant and linkers. The interacting residues between the candidate vaccine and the TLR molecules have been identified.

INTERPRETATION & CONCLUSION

The proposed multiepitope candidate vaccine was designed from the mosquito salivary protein OBP 22 and OBP 10. The candidate vaccine was found promising for the protection against arboviruses. Further clinical validation is warranted to prove its efficacy, safety and immunogenicity for its potential use.

The impact of Chikungunya chronic arthralgia on women’s upper limbs motor function: a cross-sectional study

ABSTRACT Post-Chikungunya chronic arthralgia (PCCA) may lead to musculoskeletal repercussions and functional loss. The objective was to assess the upper limb physical disability and symptoms during daily, work, and leisure activities of women presenting PCCA compared to healthy controls (HC). This was a cross-sectional study conducted with 52 women. The participants were divided into PCCA (37) and HC (15) groups. Handgrip strength, range of motion, level of pain (numerical rating scale), and participants’ physical disability and symptoms (Disabilities of the Arm, Shoulder, and Hand Questionnaire - DASH) were evaluated. Differences between groups were evaluated using the Students t-test and Pearson’s correlations. The chi-square test was applied for categorical variables. The significance was set at α=0.05. The disease duration was 19.5±13.1 months. We found no differences between groups for peak force (PCAA:23.6±7.4kgf; HC: 24.5±6.2kgf; p=0.676). The results showed a significant difference between groups regarding range of motion (PCCA: 63.5±17.3o; HC: 77.2±9.6o), level of hand pain (PCCA: 5.8±2.2; HC: 0.4±1.5), and upper limbs functional levels (PCCA: 44.5±17.4; HC: 16.2±20.5). Participants related severe difficulty or inability to perform tasks such as opening a jar (78.4%), placing objects above head height (48.7%), doing heavy household chores (56.8%), and gardening (51.4%). Impairment in the upper limb physical function in daily, work, and leisure activities shows the higher prevalence in the long-term.

Epidemic Retinitis with Positive or Negative Weil Felix Test - a Comparative Study and Outcome with Doxycycline

PURPOSE

To compare clinical manifestations and disease outcomes in Epidemic Retinitis (ER) with positive or negative Weil Felix Test (WFT).

METHODS

Retrospective, observational, comparative study. WFT positive or negative patients formed Group 1 and 2, respectively. Patients receiving oral doxycycline monotherapy formed subgroup A and B. Duration of resolution of macular edema and retinitis was compared.

RESULTS

Novel finding of "ring retinitis" was observed equally in group 1 and 2. Complete resolution of macular edema took 41.3 days (range: 30-60 days) and 43.68 days (range: 20-105 days) (p = .668) and retinitis lesions resolved in 34.3 days (range: 14-65 days) and 34 days (range: 12-60 days) (p = .875) in group A and B, respectively. All (n = 14) eyes with retinitis within 1 disc diameter of fovea improved better than 20/80 except 1.

CONCLUSION

No significant difference with respect to clinical, imaging findings and the treatment outcome was observed in WFT positive or negative cases.

Virological, Serological and Clinical Analysis of Chikungunya Virus Infection in Thai Patients

From 2018 to 2020, the Chikungunya virus (CHIKV) outbreak re-emerged in Thailand with a record of more than 10,000 cases up until the end of 2020. Here, we studied acute CHIKV-infected patients who had presented to the Bangkok Hospital for Tropical Diseases from 2019 to 2020 by assessing the relationship between viral load, clinical features, and serological profile. The results from our study showed that viral load was significantly high in patients with fever, headache, and arthritis. We also determined the neutralizing antibody titer in response to the viral load in patients, and our data support the evidence that an effective neutralizing antibody response against the virus is important for control of the viral load. Moreover, the phylogenetic analysis revealed that the CHIKV strains we studied belonged to the East, Central, and Southern African (ECSA) genotype, of the Indian ocean lineage (IOL), and possessed E1-K211E and E1-I317V mutations. Thus, this study provides insight for a better understanding of CHIKV pathogenesis in acute infection, along with the genomic diversity of the current CHIKV strains circulating in Thailand.

Chikungunya Immunopathology as It Presents in Different Organ Systems

Chikungunya virus (CHIKV) is currently an urgent public health problem as high morbidity from the virus leaves populations with negative physical, social, and economic impacts. CHIKV has the potential to affect every organ of an individual, leaving patients with lifelong impairments which negatively affect their quality of life. In this review, we show the importance of CHIKV in research and public health by demonstrating the immunopathology of CHIKV as it presents in different organ systems. Papers used in this review were found on PubMed, using “chikungunya and [relevant organ system]”. There is a significant inflammatory response during CHIKV infection which affects several organ systems, such as the brain, heart, lungs, kidneys, skin, and joints, and the immune response to CHIKV in each organ system is unique. Whilst there is clinical evidence to suggest that serious complications can occur, there is ultimately a lack of understanding of how CHIKV can affect different organ systems. It is important for clinicians to understand the risks to their patients.

Role of cytokines, chemokines, C3a, and mannose-binding lectin in the evolution of the chikungunya infection

The pathogenesis of the severity of chikungunya infection is not yet fully understood.

OBJECTIVE

To assess the role of the cytokines/chemokines and system of complement in the evolution of chikungunya infection.

METHODS

In both acute and chronic phases, we measured the serum levels of 12 cytokines/chemokines and two complement mediators: mannose-binding lectin (MBL) and C3a, in 83 patients with chikungunya infection and ten healthy controls.

RESULTS

During the acute phase, 75.9% of the patients developed musculoskeletal disorders, and in 37.7% of them, these disorders persisted until the chronic phase. In general, patients had higher levels of cytokines than healthy controls, with significant differences for IFN-γ, IL-6, IL-8, IL-10, and MIP-1. Most cytokines exhibited a downward trend during the chronic phase. However, only IL-10, and MIP-1 levels were significantly lower in the chronic phase. Additionally, these levels never decreased to concentrations found in healthy controls. Moreover, MBL levels were significantly higher in the acute phase compared with the chronic phase. C3a levels were significantly higher in patients with musculoskeletal disorder compared with patients without it, in both acute-phase 118.2 (66.5-252.9), and chronic phase 68.5 (64.4-71.3), P < 0.001. Interestingly, C3a levels were significantly higher when patients had a severe disease version. Besides, in the acute phase, C3a levels were higher in patients that suffer arthritis as opposed to when they suffer arthralgia, 194.3 (69.5-282.2), and 70.9 (62.4-198.8), P = 0.013, respectively.

CONCLUSIONS

Our results showed an immunological response that persisted until the chronic phase and the role of the complement system in the severity of the disease.

[Important arboviral diseases in returning travelers: dengue, chikungunya and zika]

Arboviral infections are an important differential diagnosis in returning travelers with fever, muscle or joint pain and rash. Arboviruses have spread widely around the globe in the last decades. The most common arboviral infections in returning travelers from tropical and subtropical areas are dengue, chikungunya and zika. Their most important vectors, Aedes (Stegomyia) mosquito species, have adapted to the urban environment, which enabled arboviruses to establish urban transmission cycles. Population growth, urbanization, globalization, modern means of transportation and global warming are speeding up their spread.Laboratory confirmation of an arboviral infection can generally be obtained by direct virus detection (PCR, antigen test) in the first week of illness; from the second week of illness serology can be used. Treatment is mostly symptomatic.Dengue fever is the most common cause of fever in returning travelers from South-East Asia. Patients have to be educated about and observed for warning signs of severe dengue that can rarely develop around day 5 of the disease and is marked by a rise in hematocrit.Chikungunya mostly occurs in epidemics and is characterized by severe and often long-lasting arthritis.Preconceptional screening for zika virus infection is not recommended. Instead, travelers should delay conception for up to three months after returning from a zika endemic area.Dengue, chikungunya and zika vaccine development has been hampered by difficulties, for example antibody-dependent-enhancement or the unpredictability of outbreaks, and up to now no vaccines for travelers have been licensed. Yet several promising vaccine candidates are currently under development.

Long-term Chikungunya sequelae and quality of life 2.5 years post-acute disease in a prospective cohort in Curaçao

Background

Little is known about the persistence and impact of non-rheumatic symptoms after acute chikungunya disease. We have studied the clinical presentation and long-term impact of rheumatic and non-rheumatic symptoms on health related quality of life (QoL) 2.5 years after disease onset. Additionally, the validity of the Curaçao Long-Term Chikungunya Sequelae (CLTCS) score in classifying disease severity over time was evaluated.

Methodology/Principal findings

This prospective cohort study followed 248 chikungunya patients. Symptoms and SF-36 QoL were evaluated during baseline and follow-up at 2.5 years using questionnaires. Chikungunya disease status was classified using the CLTCS-score. At 2.5 years after disease onset patients were classified as being recovered (43%), mildly (35%) or highly (22%) affected. In comparison to mildly affected, highly affected patients reported the highest prevalence of ongoing rheumatic and non-rheumatic/psychological symptoms, with increased prevalence of arthralgia in the lower extremities (p = .01) and fatigue (p = .049) over time, and higher pain intensity (p < .001). Compared to mildly affected, being highly affected was associated with weakness in the lower extremities (OR: 1.90; CI: 1.29–2.80, p = .001) and worsened physical and mental QoL impairment.

Conclusions

Patients are both physically and psychologically affected by rheumatic and non-rheumatic symptoms of long-term chikungunya disease.

The CLTCS-score is an easy to use instrument for classifying long-term chikungunya disease severity and impact and can facilitate health care providers in identifying highly affected patients who are prone to develop severe QoL impairment. Highly affected patients are recommended to be treated in a multidisciplinary setting to improve physical and psychological functioning, and QoL.

Chikungunya disease manifestation is characterized by a sudden onset of non-rheumatic flu-like symptoms and debilitating rheumatic symptoms in the acute phase. Little is known about the persistence of non-rheumatic symptoms after acute disease. In this prospective cohort study we investigated the clinical manifestations and persistence of baseline rheumatic and non-rheumatic/psychological symptoms and their impact on health related quality of life (QoL) 2.5 years after disease onset. Moreover, we investigated the performance of the classification instrument the Curaçao Long-Term Chikungunya Sequelae (CLTCS) score in classifying chikungunya disease severity over time. We found that 57% of the patients were still affected 2.5 years after disease onset. An increase of mainly recurrent rheumatic and non-rheumatic/psychological symptoms including fatigue, insomnia, sombreness, and loss of vitality were reported, with a significantly higher symptom recurrence and pain intensity reported by highly affected patients. In addition, QoL assessment indicates that the disease burden impaired the physiological well-being of these patients. We also showed that the CLTCS-score can be used to easily identify highly affected patients. This study demonstrates that disease severity increases non-rheumatic symptoms and subsequent physiological impairments and suggests a multidisciplinary treatment approach to treat the psychological effects of long-term chikungunya disease.

Neglected tropical rheumatic diseases

The complexities of dealing with rheumatic diseases in tropical countries are diverse and likely due to limited health care infrastructure, lack of diagnostic and therapeutic facilities, impact of dominant prevailing diseases, and the challenges of differentiating from infectious and non-infectious disease mimics. Several tropical diseases present with musculoskeletal and rheumatic manifestations and often pose a diagnostic dilemma to rheumatologists. The diagnosis is often delayed or the disease is misdiagnosed, leading to poor patient outcomes. Endemic tropical diseases like tuberculosis and leprosy have myriad rheumatic presentations and remain important differentials to consider in patients with rheumatic manifestations. Infection with human immunodeficiency virus is a great masquerade and can mimic manifestations of multiple diseases. The role of viral infections in triggering and perpetuating autoimmunity is well known and chikungunya arthritis is a classic example of the same. This review highlights the rheumatic manifestations of tropical diseases and aims to create awareness among the caregivers. Key Points • It is crucial to be aware and identify infectious diseases presenting with rheumatic manifestations in the tropics. • Presentations akin to classic rheumatic syndromes such as rheumatoid arthritis, spondyloarthritis, systemic lupus erythematosus and vasculitis are common.

Chikungunya and arthritis: An overview

Chikungunya is caused by CHIKV (chikungunya virus), an emerging and re-emerging arthropod-vectored viral infection that causes a febrile disease with primarily long term sequelae of arthralgia and myalgia and is fatal in a small fraction of infected patients. Sporadic outbreaks have been reported from different parts of the world chiefly Africa, Asia, the Indian and Pacific ocean regions, Europe and lately even in the Americas. Currently, treatment is primarily symptomatic as no vaccine, antibody-mediated immunotherapy or antivirals are available. Chikungunya belongs to a family of arthritogenic alphaviruses which have many pathophysiological similarities. Chikungunya arthritis has similarities and differences with rheumatoid arthritis. Although research into arthritis caused by these alphaviruses have been ongoing for decades and significant progress has been made, the mechanisms underlying viral infection and arthritis are not well understood. In this review, we give a background to chikungunya and the causative virus, outline the history of alphavirus arthritis research and then give an overview of findings on arthritis caused by CHIKV. We also discuss treatment options and the research done so far on various therapeutic intervention strategies.

Pentosan polysulfate sodium prevents functional decline in chikungunya infected mice by modulating growth factor signalling and lymphocyte activation

Chikungunya virus (CHIKV) is an arthropod-borne virus that causes large outbreaks world-wide leaving millions of people with severe and debilitating arthritis. Interestingly, clinical presentation of CHIKV arthritides have many overlapping features with rheumatoid arthritis including cellular and cytokine pathways that lead to disease development and progression. Currently, there are no specific treatments or vaccines available to treat CHIKV infections therefore advocating the need for the development of novel therapeutic strategies to treat CHIKV rheumatic disease. Herein, we provide an in-depth analysis of an efficacious new treatment for CHIKV arthritis with a semi-synthetic sulphated polysaccharide, Pentosan Polysulfate Sodium (PPS). Mice treated with PPS showed significant functional improvement as measured by grip strength and a reduction in hind limb foot swelling. Histological analysis of the affected joint showed local inflammation was reduced as seen by a decreased number of infiltrating immune cells. Additionally, joint cartilage was protected as demonstrated by increased proteoglycan staining. Using a multiplex-immunoassay system, we also showed that at peak disease, PPS treatment led to a systemic reduction of the chemokines CXCL1, CCL2 (MCP-1), CCL7 (MCP-3) and CCL12 (MCP-5) which may be associated with the reduction in cellular infiltrates. Further characterisation of the local effect of PPS in its action to reduce joint and muscle inflammation was performed using NanoString™ technology. Results showed that PPS altered the local expression of key functional genes characterised for their involvement in growth factor signalling and lymphocyte activation. Overall, this study shows that PPS is a promising treatment for alphaviral arthritis by reducing inflammation and protecting joint integrity.

Sales of antibiotics and hydroxychloroquine in India during the COVID-19 epidemic: An interrupted time series analysis

BACKGROUND

We assessed the impact of the coronavirus disease 2019 (COVID-19) epidemic in India on the consumption of antibiotics and hydroxychloroquine (HCQ) in the private sector in 2020 compared to the expected level of use had the epidemic not occurred.

METHODS AND FINDINGS

We performed interrupted time series (ITS) analyses of sales volumes reported in standard units (i.e., doses), collected at regular monthly intervals from January 2018 to December 2020 and obtained from IQVIA, India. As children are less prone to develop symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we hypothesized a predominant increase in non-child-appropriate formulation (non-CAF) sales. COVID-19-attributable changes in the level and trend of monthly sales of total antibiotics, azithromycin, and HCQ were estimated, accounting for seasonality and lockdown period where appropriate. A total of 16,290 million doses of antibiotics were sold in India in 2020, which is slightly less than the amount in 2018 and 2019. However, the proportion of non-CAF antibiotics increased from 72.5% (95% CI: 71.8% to 73.1%) in 2019 to 76.8% (95% CI: 76.2% to 77.5%) in 2020. Our ITS analyses estimated that COVID-19 likely contributed to 216.4 million (95% CI: 68.0 to 364.8 million; P = 0.008) excess doses of non-CAF antibiotics and 38.0 million (95% CI: 26.4 to 49.2 million; P < 0.001) excess doses of non-CAF azithromycin (equivalent to a minimum of 6.2 million azithromycin treatment courses) between June and September 2020, i.e., until the peak of the first epidemic wave, after which a negative change in trend was identified. In March 2020, we estimated a COVID-19-attributable change in level of +11.1 million doses (95% CI: 9.2 to 13.0 million; P < 0.001) for HCQ sales, whereas a weak negative change in monthly trend was found for this drug. Study limitations include the lack of coverage of the public healthcare sector, the inability to distinguish antibiotic and HCQ sales in inpatient versus outpatient care, and the suboptimal number of pre- and post-epidemic data points, which could have prevented an accurate adjustment for seasonal trends despite the robustness of our statistical approaches.

CONCLUSIONS

A significant increase in non-CAF antibiotic sales, and particularly azithromycin, occurred during the peak phase of the first COVID-19 epidemic wave in India, indicating the need for urgent antibiotic stewardship measures.

An updated RT-qPCR assay for the simultaneous detection and quantification of chikungunya, dengue and zika viruses

The real-time reverse transcription-polymerase chain reaction (real-time RT-qPCR) has become a leading technique for the detection and quantification of arboviruses, including Chikungunya, Dengue, and Zika viruses. In this study, an updated real-time RT-qPCR assay was designed and evaluated together with a synthetic positive-control chimeric RNA for the simultaneous detection and quantification of Chikungunya, Dengue, and Zika viruses. Amplification assays were performed to verify the construct integrity and optimal reaction/thermal cycling conditions. The analytical sensitivity of the assay was determined for each virus in single and multiplex reactions, as well as the performance in the detection and viral load quantification of experimental samples. The real-time RT-qPCR assay presented here allowed for the simultaneous detection and quantification of Chikungunya, Dengue, and Zika viruses and could be applied in several studies where the accurate quantification of viral genomes is required.

Ankle arthritis - an important signpost in rheumatologic practice

Ankle arthritis is a useful clinical signpost to differential diagnosis in rheumatic disease. Biomechanical features and differences in cartilage physiology compared with the knee may confer protection of the ankle joint from factors predisposing to certain arthritides. The prevalence of ankle OA is low, and usually secondary to trauma. Primary OA of the ankle should be investigated for underlying causes, especially haemochromatosis. New presentations of inflammatory mono/oligo arthritis involving the ankle are more likely due to undifferentiated arthritis or spondyloarthritis than RA, and gout over CPPD. The ankle is often involved in bacterial and viral causes of septic arthritis, especially bacterial, chikungunya and HIV infection, but rarely tuberculosis. Periarticular hind foot swelling can be confused with ankle arthritis, exemplified by Lofgren’s syndrome and hypertrophic osteoarthropathy where swelling is due to subcutaneous oedema and osteitis respectively, and the ankle joint is rarely involved.

Role of MicroRNAs in Bone Pathology during Chikungunya Virus Infection

Chikungunya virus (CHIKV) is an alphavirus, transmitted by mosquitoes, which causes Chikungunya fever with symptoms of fever, rash, headache, and joint pain. In about 30%-40% of cases, the infection leads to polyarthritis and polyarthralgia. Presently, there are no treatment strategies or vaccine for Chikungunya fever. Moreover, the mechanism of CHIKV induced bone pathology is not fully understood. The modulation of host machinery is known to be essential in establishing viral pathogenesis. MicroRNAs (miRNAs) are small non-coding RNAs that regulate major cellular functions by modulating gene expression. Fascinatingly, recent reports have indicated the role of miRNAs in regulating bone homeostasis and altered expression of miRNAs in bone-related pathological diseases. In this review, we summarize the altered expression of miRNAs during CHIKV pathogenesis and the possible role of miRNAs during bone homeostasis in the context of CHIKV infection. A holistic understanding of the different signaling pathways targeted by miRNAs during bone remodeling and during CHIKV-induced bone pathology may lead to identification of useful biomarkers or therapeutics.

Persistence of chikungunya ECSA genotype and local outbreak in an upper medium class neighborhood in Northeast Brazil

The chikungunya East/Central/South/Africa virus lineage (CHIKV-ECSA) was first detected in Brazil in the municipality of Feira de Santana (FS) by mid 2014. Following that, a large number of CHIKV cases have been notified in FS, which is the second-most populous city in Bahia state, northeastern Brazil, and plays an important role on the spread to other Brazilian states due to climate conditions and the abundance of competent vectors. To better understand CHIKV dynamics in Bahia state, we generated 5 complete genome sequences from a local outbreak raised in Serraria Brasil, a neighbourhood in FS, by next-generation sequencing using Illumina approach. Phylogenetic reconstructions revealed that the new FS genomes belongs to the ECSA genotype and falls within a single strongly supported monophyletic clade that includes other older CHIKV sequences from the same location, suggesting the persistence of the virus during distinct epidemic seasons. We also performed minor variants analysis and found a small number of SNPs per sample (b_29L and e_45SR = 16 SNPs, c_29SR = 29 and d_45PL and f_45FL = 21 SNPs). Out of the 93 SNPs found, 71 are synonymous, 21 are non-synonymous and one generated a stop codon. Although those mutations are not related to the increase of virus replication and/or infectivity, some SNPs were found in non-structural proteins which may have an effect on viral evasion from the mammal immunological system. These findings reinforce the needing of further studies on those variants and of continued genomic surveillance strategies to track viral adaptations and to monitor CHIKV epidemics for improved public health control.