Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus responsible for a recent, unexpectedly severe epidemic in countries of the Indian Ocean region. Although many alphaviruses have been well studied, little was known about the biology and pathogenesis of CHIKV at the time of the 2005 outbreak. Over the past 5 years there has been a multidisciplinary effort aimed at deciphering the clinical, physiopathological, immunological and virological features of CHIKV infection. This Review highlights some of the most recent advances in our understanding of the biology of CHIKV and its interactions with the host.

Biology and pathogenesis of chikungunya virus

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(11)60281-X.pdf

Chikungunya: a re-emerging virus

Alphaviruses, including Chikungunya virus (CHIKV), produce a transient illness in humans, but severe forms leading to chronic incapacitating arthralgia/arthritis have been reported by mechanisms largely ill-characterized. The pathogenesis of CHIKV was addressed in a prospective cohort study of 49 hospitalized patients from Reunion Island subsequently categorized into two distinct groups at 12 mo postinfection. Comprehensive analyses of the clinical and immunological parameters throughout the disease course were analyzed in either the “recovered” or the “chronic” groups to identify prognostic markers of arthritis-like pathology after CHIKV disease. We found that the chronic group consisted mainly of more elderly patients (\textgreater60 y) and with much higher viral loads (up to 1010 viruses per milliliter of blood) during the acute phase. Remarkably, a rapid innate immune antiviral response was demonstrated by robust dendritic/NK/CD4/CD8 cell activation and accompanied by a rather weak Th1/Th2 cytokine response in both groups. Interestingly, the antiviral immune response witnessed by high levels of IFN-α mRNA in PBMCs and circulating IL-12 persisted for months only in the chronic group. CHIKV (RNA and proteins) was found in perivascular synovial macrophages in one chronic patient 18 mo postinfection surrounded by infiltrating NK and T cells (CD4++ but rare cytotoxic CD8). Fibroblast hyperplasia, strong angiogenesis, tissue lesions given the high levels of matrix metalloproteinase 2, and acute cell death [high cleaved poly(ADP-ribose) polymerase staining] were observed in the injured synovial tissue. These observed cellular and molecular events may contribute to chronic arthralgia/arthritis targeted by methotrexate used empirically for effective treatment but with immunosuppressive function in a context of viral persistence.

Persistent Chronic Inflammation and Infection by Chikungunya Arthritogenic Alphavirus in Spite of a Robust Host Immune Response

Alphaviruses can cause rheumatic manifestations (usually polyarthralgia and/or polyarthritis) in humans. Arthritogenic alphaviruses are distributed globally and include chikungunya virus, Ross River virus, Barmah Forest virus, Sindbis virus, o'nyong nyong virus and Mayaro virus. In this Review, the authors provide an overview of these viruses, describing epidemiology, pathogenesis, disease manifestations, diagnosis and interventions.

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Arthritogenic alphaviruses—an overview

The incidence of acute kidney injury (AKI) in the intensive care unit (ICU) has increased during the past decade due to increased acuity as well as increased recognition. Early epidemiology studies were confounded by erratic definitions of AKI until recent consensus guidelines (RIFLE and AKIN) standardized its definition. This paper discusses the incidence of AKI in the ICU with focuses on specific patient populations. The overall incidence of AKI in ICU patients ranges from 20% to 50% with lower incidence seen in elective surgical patients and higher incidence in sepsis patients. The incidence of contrast-induced AKI is less (11.5%–19% of all admissions) than seen in the ICU population at large. AKI represents a significant risk factor for mortality and can be associated with mortality greater than 50%.

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Epidemiology of Acute Kidney Injury in the Intensive Care Unit

Systemic involvements and fatalities during Chikungunya epidemic in India, 2006.

Stroke care in India has evolved rapidly in the last decade with a focus on stroke awareness, prevention, rapid triage, treatment, and rehabilitation. But acute stroke care and poststroke rehabilitation in the country have limitations owing to the economic constraints and poor access to health care. The SARS-CoV-2/COVID-19 pandemic has made stroke care even more challenging. We outline the unfavorable circumstances in stroke care induced by the pandemic; propose mitigating measures; crisis management; and provide a comparative evaluation of stroke care between India and the United States during the pandemic. There is a need for public health systems in both developed and developing countries to improve awareness, implement proper strategies of triage, acute treatment, well-defined rehabilitation plans, telemedicine services, and virtual check-ins.

/pdf/the-sars-cov-2-covid-19-pandemic-and-challenges-in-stroke-3uj7dacko2.pdf

The SARS-CoV-2/COVID-19 pandemic and challenges in stroke care in India.

Neurological complications of influenza are well known. Influenza A is commonly associated with neurological complications. Neurological complications especially encephalitis is described in the pediatric age group of patients with current pandemic novel H1N1 infection. We are describing a case of novel H1N1 infection presenting with multi-system involvement (encephalitis, bilateral pneumonia, severe rhabdomyolysis leading to renal failure and polyneuropathy) in adult patient.

Adult Patient with Novel H1N1 Infection Presented with Encephalitis, Rhabdomyolysis, Pneumonia and Polyneuropathy.

Aims: To study the impact of vestibular suppressant drugs (VSD) on provocative positional tests (PPT) in patients with benign paroxysmal positional vertigo (BPPV). Settings and Design: A prospective case-control observational study. Materials and Methods: Patients with a history suggestive of BPPV were tested for PPT. Patients with vertiginous symptoms and with nystagmus on PPT were classified as objective BPPV (O-BPPV, control group), while those without nystagmus with no alternate diagnosis were classified as subjective BPPV (S-BPPV, case group). Details of VSD treatment were noted in all the patients. In both groups, patients were instructed to discontinue VSD and were further assigned as the VSD and non-VSD subgroups. Patients were followed for 2 months with PPT every week. PPT positive patients were treated by vestibular rehabilitation maneuvers. Statistics: Student t-test with two-tailed, unpaired, was used for continuous scale and Chi-square test for categorical differences between the two groups. Results: 295 consecutive BPPV patients were enrolled in the study, 55 in the S-BPPV group and 240 in the O-BPPV group. Significantly higher proportion of patients in the S-BPPV group were on VSD at presentation, 80.00% vs. 53.75% (OR 2.52; 95% CI: 1.30–4.86), P = 0.006. In an unadjusted analysis of the S-BPPV group following discontinuation of VSD, PPT became positive in 79.54% of patients as compared to 18.19% in the non-VSD group (OR 35.0; 95% CI: 6.2–197.3), P Study Design: Prospective case-control observational study.

Sudhir Shah

Papers

Systemic involvements and fatalities during Chikungunya epidemic in India, 2006.

The SARS-CoV-2/COVID-19 pandemic and challenges in stroke care in India.

Adult Patient with Novel H1N1 Infection Presented with Encephalitis, Rhabdomyolysis, Pneumonia and Polyneuropathy.

Negative Impact of Vestibular Suppressant Drugs on Provocative Positional Tests of BPPV: A Study from the Western Part of India.

A Rare Case of Hypokalemic Paralysis - Conn’s Syndrome.