Detection of human parvovirus 4 DNA in the patients with acute encephalitis syndrome during seasonal outbreaks of the disease in Gorakhpur, India

Study on genotyping and coinfection rate of human parvovirus 4 among the HTLV-I/II infected blood donors in Khorasan Razavi, Iran

Human Parvovirus 4 (PARV4) is an emerging virus infecting individuals with other blood-borne diseases. This study aimed to determine the prevalence of PARV4 in confirmed HTLVI/II positive samples from blood donors, assessing PARV4 viral load (DNA) and genotyping.

METHODS

A novel qReal-Time PCR, based on a plasmid construct, was developed to simultaneously detect all three PARV4 genotypes using in-house primers and probes. Positive qPCR samples were subjected to nested PCR amplification and subsequent sequencing. Phylogenetic trees were constructed using the Neighbor-joining (N.J.) method.

RESULTS

The coinfection rate of PARV4-DNA in HTLVI/II confirmed infected donors, who were previously deferred, was 14.4 % (13 out of 90), with no observed association with donation status (p = 1.0). Phylogenetic analysis indicated that PARV4-positive samples closely resembled genotype 2 in Iran.qPCR quantification demonstrated significant PARV4 viral loads in positive samples, ranging between 104 and 106 DNA copies/mL of serum.

CONCLUSION

This study presents the first evaluation of HTLVI/II and PARV4coinfection rates among blood donors. Notably, elevated PARV4-DNA titers were detected in HTLVI/II-positive donors. Given PARV's resistance to standard plasma refinery inactivation methods and the absence of its targeted inactivation, its potential impact remains a concern.

Global magnitude of encephalitis burden and its evolving pattern over the past 30 years

OBJECTIVE

We aimed to estimate the spatiotemporal patterns of the encephalitis burden along with its attributable risk factors at the national, regional, and global levels, which may be helpful in guiding targeted prevention and treatment programs.

METHODS

Based on available data sources, the incidence, mortality, and disability-adjusted life years (DALYs) of encephalitis in 204 countries and regions from 1990 to 2019 were reconstructed by the Global Burden of Disease Study 2019 using the Cause of Death Ensemble model, spatiotemporal Gaussian process regression, and DisMod-MR 2.1. We conducted a systematic analysis on the epidemiological characteristics of encephalitis in detail by gender, region, and age over the past three decades.

RESULTS

Globally, 1,444,720 incident cases, 89,900 deaths, and 4.80 million DALYs related to encephalitis were estimated in 2019. The age-standardized incidence rate and age-standardized mortality rate (ASMR) decreased from 23.17 and 2.18 to 19.33 and 1.19 per 100,000 person-years over the past 30 years, respectively. However, beginning in 2011-2013, the burden of encephalitis has shown an inflection point, with a further decline of the ASRs ceasing. Lower socio-demographic index (SDI) regions in South Asia, Western and Eastern Sub-Saharan Africa had the highest burden of encephalitis in 2019. During the past three decades, most countries of South Asia achieved significant control of the burden. In contrast, developed countries with a higher SDI have shown a notable increase in ASMR and age-standardized DALYs rate. Children and older adults have always been high-risk groups for encephalitis.

CONCLUSION

Although the global burden of encephalitis has decreased in the past 30 years, a further decline stopped from 2011-2013. The diverse burden in different regions calls for differentiated management, and the persistent high burden in some low-SDI regions and the increased burden in developed countries with higher SDIs deserve more attention.

ABBREVIATIONS

ASDR: age-standardized DALY rate, ASIR: age-standardized incidence rate, ASMR: age-standardized mortality rate, ASR: age-standardized rate, CI: confidence interval, DALY: disability-adjusted life-year, EAPC: estimated annual percentage change, GBD: Global Burden of Disease Study, HAP: household air pollution from solid fuels, HSE: herpes simplex encephalitis, HSV: herpes simplex virus, ICD: International Classification of Diseases, JE: Japanese encephalitis, PCR: polymerase chain reaction, SDI: socio-demographic index, TBE: tick-borne encephalitis, UI: uncertainty interval.

Identification of human parvovirus 4 genotypes 1 and 2 in Chinese source plasma pools

Human parvovirus B19 (B19V) and human parvovirus 4 (PARV4) are known to infect humans and transmit through contaminated blood and blood products. Globally, three genotypes of B19V, as well as PARV4, have been identified, respectively. The existence of different B19V genotypes in Chinese plasma donors has been investigated, however, the data regarding PARV4 were not available. The main objective of this study is to identify the genotypes of PARV4 circulating in Chinese plasma donors. By using a duplex quantitative polymerase chain reaction assay adapted for all genotypes of B19V and PARV4, 78 source plasma pools for fractionation were screened and quantified. Results showed that positive rates of B19V and PARV4 DNA in plasma pool samples were 25.64% and 14.10%, respectively. PARV4 sequences in two positive samples were next genotyped, and these two sequences belonged to PARV4 genotypes 1 and 2, respectively. In conclusion, the data present demonstrate the existence of PARV4 genotypes 1 and 2 in Chinese plasma donors for the first time and also show the relatively lower prevalence and level of PARV4 DNA in Chinese plasma donors in comparison with that of B19V DNA.

At least two PARV4 genotypes, 1 and 2, were currently present in China.

The prevalence and level of PARV4 DNA in Chinese plasma donors were relatively lower in comparison with that of B19V DNA.

The rate of B19V and PARV4 coinfection in Chinese source plasma pools was low.

Next-generation Sequencing of Cerebrospinal Fluid for the Diagnosis of Unexplained Central Nervous System Infections

BACKGROUND

Central nervous system infections cause substantial morbidity and mortality in pediatric patients. However, in approximately half of the clinical cases, the etiology is unidentified. As an unbiased molecular diagnostic technology, next-generation sequencing is gradually being applied to investigate central nervous system infections. This review summarizes and critiques the literature on this new technology for etiologic identification of unexplained central nervous system infections in pediatric patients and discusses the future prospects for development of this technology in pediatrics.

METHODS

A comprehensive PubMed search was conducted of articles published from January 1, 2008, to June 26, 2020 in order to retrieve all available studies on this topic. Other relevant articles were identified from recent reviews and the bibliographies of the retrieved full-text articles.

RESULTS

Among the 441 studies retrieved, 26 pediatric studies, comprising 15 case reports and 11 case series, used next-generation sequencing as a diagnostic tool. In these 26 studies, next-generation sequencing was performed on cerebrospinal fluid samples from 529 pediatric patients, and potential causal pathogens were identified in 22.1% of the cases.

CONCLUSION

There is increasing evidence that next-generation sequencing can play a role in identifying the causes of unexplained encephalitis, meningoencephalitis, and meningitis in pediatric patients, although the diagnostic value of next-generation sequencing is difficult to quantify. There is an increasing need for close collaboration between laboratory scientists and clinicians. We believe that further clinical studies should be performed to evaluate the performance of next-generation sequencing for individual targets and in high-risk populations.

Central Nervous System Manifestations Associated with COVID-19

Purpose of Review

Coronavirus disease 2019 (COVID-19) has become a global health crisis of our time. The disease arises from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that binds to angiotensin-converting enzyme 2 (ACE2) receptors on host cells for its internalization. COVID-19 has a wide range of respiratory symptoms from mild to severe and affects several other organs, increasing the complexity of the treatment. There is accumulating evidence to suggest that SARS-CoV-2 can target the nervous system. In this review, we provide an account of the COVID-19 central nervous system (CNS) manifestations.

Recent Findings

A broad spectrum of the CNS manifestations including headache, impaired consciousness, delirium, loss of smell and taste, encephalitis, seizures, strokes, myelitis, acute disseminated encephalomyelitis, neurogenic respiratory failure, encephalopathy, silent hypoxemia, generalized myoclonus, neuroleptic malignant syndrome and Kawasaki syndrome has been reported in patients with COVID-19.

Summary

CNS manifestations associated with COVID-19 should be considered in clinical practice. There is a need for modification of current protocols and standing orders to provide better care for COVID-19 patients presenting with neurological symptoms.

Human Parvoviruses May Affect the Development and Clinical Course of Meningitis and Meningoencephalitis

Meningitis and meningoencephalitis are neurological inflammatory diseases, and although routine diagnostics include testing of a wide range of pathogens, still in many cases, no causative agent is detected. Human parvovirus B19 (B19V), human bocaviruses 1–4 (HBoV1–4), and human parvovirus 4 (hPARV4) are members of the Parvoviridae family and are associated with a wide range of clinical manifestations including neurological disorders. The main aim of this study was to determine whether human parvoviruses infection markers are present among patients with meningitis/meningoencephalitis in Latvia as well as to clarify the role of these viruses on the clinical course of the mentioned diseases. Our study revealed HBoV1–4 and B19V genomic sequences in 52.38% and 16.67% of patients, respectively. Furthermore, symptoms such as the presence of a headache and its severity, fatigue, disorientation, and difficulties to concentrate were significantly frequently present in patients with active parvovirus infection in comparison with parvoviruses negative patients, therefore we suggest that HBoV1–4 and B19V infection should be included in the diagnostics to reduce the number of meningitis/meningoencephalitis with unknown/unexplained etiology.

Encephalopathy and Encephalitis Associated with Cerebrospinal Fluid Cytokine Alterations and Coronavirus Disease, Atlanta, Georgia, USA, 2020

There are few detailed investigations of neurologic complications in severe acute respiratory syndrome coronavirus 2 infection. We describe 3 patients with laboratory-confirmed coronavirus disease who had encephalopathy and encephalitis develop. Neuroimaging showed nonenhancing unilateral, bilateral, and midline changes not readily attributable to vascular causes. All 3 patients had increased cerebrospinal fluid (CSF) levels of anti-S1 IgM. One patient who died also had increased levels of anti-envelope protein IgM. CSF analysis also showed markedly increased levels of interleukin (IL)-6, IL-8, and IL-10, but severe acute respiratory syndrome coronavirus 2 was not identified in any CSF sample. These changes provide evidence of CSF periinfectious/postinfectious inflammatory changes during coronavirus disease with neurologic complications.