Kinetics of viral RNA, immunoglobulin-M & G antibodies in Kyasanur forest disease

Kyasanur forest disease in India: a case report

The presence of bleeding manifestations, generalized erythema, palatal petechiae, conjunctival congestion, haemoconcentration, leucopenia, thrombocytopenia, raised transaminases and coagulopathy in a patient with a history of residence or travel to endemic regions in South India should alert the travel medicine practitioner to the possibility of Kyasanur forest disease.

Kyasanur Forest Disease: A Comprehensive Review

Vector-borne microbial diseases are ubiquitous, and their management remains elusive. Such diseases with zoonotic potential result in public health challenges requiring additional control and preventive measures. Despite their cosmopolitan presence, vector-borne infections are neglected due to their endemicity in specified geographical regions. The Kyasanur forest disease (KFD) caused by the Kyasanur forest disease virus (KFDV) is among such diseases transmitted through ticks and localized to India. Despite its prevalence, high transmissibility, and potential to cause fatalities, KFDV has not been given the deserved attention by the governments. Further, KFDV circulates in the rural and wild geographical areas threatening infections to people living in these areas with limited access to medical and healthcare. Therefore, physicians, healthcare workers, and the general population need to understand the KFDV and its ecology, epidemiology, transmission, pathogenesis, laboratory diagnosis, and control and prevention as described comprehensively in this review.

Development of a clinical scoring system to make a presumptive diagnosis of Kyasanur Forest Disease: a case-control study from South India

Introduction

Kyasanur Forest Disease (KFD) is a viral haemorrhagic fever endemic in South India. Based on clinical presentation alone, it is challenging to distinguish KFD from other febrile illnesses in the region. The study aimed to develop a clinical scoring system for early presumptive diagnosis of KFD.

Patients and methods

This retrospective case-control study included microbiologically diagnosed KFD patients (n=186) with other undifferentiated febrile illnesses as controls (n=203). The clinical and laboratory features between cases and controls were compared. A logistic regression analysis included those variables found to be significantly associated with KFD on univariate analysis. The adjusted odds ratio for the significant variables was calculated and converted into logarithmic scales. These numbers were rounded off to the nearest integer to find the score assigned to each variable. A receiver operating characteristics curve was created to find the best cut-off for the scoring system that predicted the diagnosis of KFD.

Results

A total of 186 anonymised cases and 203 anonymised controls were recruited from the records for this study. Myalgia, headache, lymphadenopathy, bleeding manifestations, Central Nervous System (CNS) involvement, raised haematocrit, leukopenia, and raised transaminases were more common in patients with KFD. Except for lymphadenopathy and raised transaminases, all the other variables were independent predictors of making a diagnosis of KFD. Since raised transaminases tended towards significance, it was included in the scoring system with other independent predictors. A scoring system was created with a maximum score of 12. The receiver operating characteristic curve showed an Area Under Curve of 0.912 (95%CI: 0.88-0.94). A score of 4 or more was found to have a sensitivity and specificity of 83% and 87%, respectively.

Conclusion

The presence of specific features should alert primary care physicians working in endemic areas about the possibility of KFD. This diagnostic scoring system can be used to make a presumptive diagnosis of KFD after undergoing a prospective validation study.

Kyasanur forest disease: a state-of-the-art review

Kyasanur forest disease (KFD) virus is a flavivirus that can be transmitted to humans from monkeys or other mammals through hard ticks (Haemaphysalis spinigera). The disease is endemic to 16 districts in 5 states of Southern India and is reported in the dry season, most commonly in humans travelling to the forests in these areas. The aim of this systematic review is to raise awareness of the clinical and laboratory manifestation of KFD among physicians and travel medicine practitioners. A total of 153 articles were screened of which 16 articles that met the inclusion and exclusion criteria were included for qualitative analysis. KFD is an acute haemorrhagic fever with a biphasic component in some individuals. The second phase is usually marked by neurological symptoms. Leucopoenia, thrombocytopenia and elevated transaminases are the hallmarks of the first phase of KFD. The diagnostic modality of choice in the first few days of illness is polymerase chain reaction assay, whereas serology is used in the late phase. In the absence of a specific antiviral treatment, the clinical management of patients is limited to supportive care. Avoidance of exposure and vaccination is recommended to prevent this infection.

Human Alkhumra hemorrhagic Fever: Emergence, history and epidemiological and clinical profiles

Alkhumra hemorrhagic fever (AHF) is a severe, often fatal hemorrhagic disease in humans. It is caused by Alkhumra hemorrhagic fever virus (AHFV), a newly described flavivirus first isolated in 1995 in Alkhumra district, south of Jeddah City, Saudi Arabia. It is transmitted from infected livestock animals to humans by direct contact with infected animals or by tick bites. In the recent past, the incidence of AHF has increased, with a total of 604 confirmed cases have been reported in Saudi Arabia between 1995 and 2020. Yet, no specific treatment or control strategies have been developed and implemented against this infection. Hence, the likelihood of increased prevalence or the occurrence of outbreaks is high, particularly in the absence of appropriate prevention and control strategies. This narrative review presents an overview of the current knowledge and future concerns about AHF globally.

Clinical and laboratory profile of patients with Kyasanur forest disease: A single-centre study of 192 patients from Karnataka, India

INTRODUCTION

Kyasanur forest disease (KFD) is a biphasic tick-borne viral fever that is endemic to 16 districts and five states of Southern India. The aim of this study was to describe the clinical/ laboratory manifestations of KFD.

MATERIALS AND METHODS

This is a retrospective cohort study of confirmed KFD patients admitted in our hospital between December 2018 and June 2019. The demographic, clinical and laboratory parameters of patients during the first and second phase of illness was recorded in a pre-defined case study form.

RESULTS

A total of 192 patients from Karnataka were diagnosed with a mean age of 46.2 ± 15.6 years and a male preponderance (57 %). Fever (99 %), myalgia (52 %), headache (43 %), cough (14 %), conjunctival congestion (14 %), altered sensorium (13 %) and haemorrhagic manifestations (8%) were seen in the first phase. A total of 18 % of the patients came back with a second febrile episode. The features of meningoencephalitis were seen in 34 % of the patients during the second phase. Leucopenia, thrombocytopenia, and increase in liver enzymes, creatine phosphokinase (CPK) and activated partial thromboplastin time (APTT) was seen in the first phase but not in the second phase. Higher age, myocarditis, altered sensorium in the first phase, hypotension at admission, lower platelet count, elevated liver enzymes, higher APTT and CPK, were significantly associated with mortality.

CONCLUSION

The primary care physicians or travel medicine practitioners should be aware of the distinct clinical and laboratory manifestations of KFD, including the ones that may signify requirements of higher levels of care.

Kyasanur Forest Disease and Alkhurma Hemorrhagic Fever Virus-Two Neglected Zoonotic Pathogens

Kyasanur Forest disease virus (KFDV) and Alkhurma hemorrhagic fever virus (AHFV) are tick-borne flaviviruses that cause life-threatening hemorrhagic fever in humans with case fatality rates of 3-5% for KFDV and 1-20% for AHFV, respectively. Both viruses are biosafety level 4 pathogens due to the severity of disease they cause and the lack of effective countermeasures. KFDV was discovered in India and is restricted to parts of the Indian subcontinent, whereas AHFV has been found in Saudi Arabia and Egypt. In recent years, both viruses have spread beyond their original endemic zones and the potential of AHFV to spread through ticks on migratory birds is a public health concern. While there is a vaccine with limited efficacy for KFDV used in India, there is no vaccine for AHFV nor are there any therapeutic concepts to combat infections with these viruses. In this review, we summarize the current knowledge about pathogenesis, vector distribution, virus spread, and infection control. We aim to bring attention to the potential public health threats posed by KFDV and AHFV and highlight the urgent need for the development of effective countermeasures.