scholarly journals Ethanol inactivation of orthonairoviruses in ixodid ticks

2021 ◽  
Author(s):  
A. Schulz ◽  
K. Methling ◽  
M. Lalk ◽  
A. Eisenbarth ◽  
M. Keller ◽  
...  
Keyword(s):  
Spectroscopic Analysis ◽  
Hemorrhagic Fever ◽  
Scientific Data ◽  
Ethanol Exposure ◽  
Ixodid Ticks ◽  
Prolonged Storage ◽  
Virus Infectivity ◽  
Virus Inactivation ◽  
Residual Concentration ◽  
H Nmr

AbstractIxodid ticks represent vectors and reservoirs for a broad range of zoonotic pathogens. Collected ticks from field studies are therefore usually stored in ethanol, which in higher concentrations effectively inactivates most of the known tick-borne pathogens. Although commonly practiced as gold standard for inactivation, hardly any scientific data demonstrate that ethanol sufficiently penetrates the comparatively thick cuticula of ticks. Therefore, Amblyomma hebraeum tick pools were stored for 21 days in ethanol (96%). Afterwards, the ethanol was removed and the ticks were homogenized. Quantitative 1H-NMR spectroscopic analysis was applied to determine the residual concentration of ethanol inside the ticks. 1H-NMR spectroscopic analysis revealed that ethanol constituted 28.3–42.6 mg of the total weight of three ticks in the pools (89.9–121.5 mg). In addition, the low-pathogenic Hazara orthonairovirus (HAZV) was used as a cell culture model for this study. The virus was exposed to ethanol concentrations between 0 and 60% and incubated under various temperature conditions for four time periods. Afterwards, the residual virus infectivity was determined by titration. Following ethanol exposure, HAZV did not grow in cells after 9 h of exposure to an ethanol concentration of 25%. These results demonstrate an extremely low ethanol resistance of the virus, which was generally in line with previously reported ethanol inactivation data for Crimean-Congo hemorrhagic fever orthonairovirus (CCHFV). After prolonged storage and impregnation, comparable ethanol concentrations are achieved in the ticks, indicating the suitability of this inactivation method also for Bunyaviruses in ticks. At the very least, a massive virus inactivation can be assumed. Definitive proof of virus inactivation would require a bioassay of ethanol-treated infected ticks under appropriate biosafety conditions.

scholarly journals Modelling the thermal inactivation of viruses from the Coronaviridae family in suspensions or on surfaces with various relative humidities

2020 ◽  
Author(s):  
Laurent Guillier ◽  
Sandra Martin-Latil ◽  
Estelle Chaix ◽  
Anne Thébault ◽  
Nicole Pavio ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Thermal Inactivation ◽  
Inactivation Kinetics ◽  
Virus Infectivity ◽  
Virus Inactivation ◽  
Public Authorities ◽  
Contact Transmission ◽  
D Values ◽  
Major Factors ◽  
The Impact

AbstractTemperature and relative humidity are major factors determining virus inactivation in the environment. This article reviews inactivation data of coronaviruses on surfaces and in liquids from published studies and develops secondary models to predict coronaviruses inactivation as a function of temperature and relative humidity. A total of 102 D-values (time to obtain a log10 reduction of virus infectivity), including values for SARS-CoV-2, were collected from 26 published studies. The values obtained from the different coronaviruses and studies were found to be generally consistent. Five different models were fitted to the global dataset of D-values. The most appropriate model considered temperature and relative humidity. A spreadsheet predicting the inactivation of coronaviruses and the associated uncertainty is presented and can be used to predict virus inactivation for untested temperatures, time points or new coronavirus strains.ImportanceThe prediction of the persistence of SARS-CoV-2 on fomites is essential to investigate the importance of contact transmission. This study collects available information on inactivation kinetics of coronaviruses in both solid and liquid fomites and creates a mathematical model for the impact of temperature and relative humidity on virus persistence. The predictions of the model can support more robust decision-making and could be useful in various public health contexts. Having a calculator for the natural clearance of SARS-CoV-2 depending on temperature and relative humidity could be a valuable operational tool for public authorities.

Kinetics of the detritiation of [10,10-3H] mianserin and related compounds in highly basic media

1990 ◽  
Vol 68 (10) ◽  
pp. 1818-1820
Author(s):  
John R. Jones ◽  
David A. Wickenden ◽  
Carel W. Funke ◽  
Frans M. Kaspersen
Keyword(s):  
Spectroscopic Analysis ◽  
Exchange Process ◽  
Apparent Increase ◽  
H Nmr ◽  
Kinetics Of ◽  
Related Compounds

A recently developed procedure (Buist etal., J. Chem. Soc. Perkins II, 169 (1990)) has been used to study the kinetics of detritiation of [10,10-3H] mianserin and two other structurally related compounds in highly basic media. Over the H− range 16–20 the stereoselectivity of the exchange process keq/kax for all three compounds is virtually constant (5 ± 1). The apparent increase at still higher basicities is associated with distinct curvature in the log k vs. H− plots, indicating the onset of another mechanism. Partial detritiation studies at higher levels of radioactivity, when combined with 3H nmr spectroscopic analysis, confirms the greater lability of the C-10 (or C-9) equatorial hydrogen. Keywords: detritiation, high basic media, mianserin.

scholarly journals Modeling the Inactivation of Viruses from the Coronaviridae Family in Response to Temperature and Relative Humidity in Suspensions or on Surfaces

2020 ◽  
Vol 86 (18) ◽  
Author(s):  
Laurent Guillier ◽  
Sandra Martin-Latil ◽  
Estelle Chaix ◽  
Anne Thébault ◽  
Nicole Pavio ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Inactivation Kinetics ◽  
Virus Infectivity ◽  
Virus Inactivation ◽  
Public Authorities ◽  
Data Set ◽  
Contact Transmission ◽  
Major Factors ◽  
Response To Temperature ◽  
The Impact

ABSTRACT Temperature and relative humidity are major factors determining virus inactivation in the environment. This article reviews inactivation data regarding coronaviruses on surfaces and in liquids from published studies and develops secondary models to predict coronaviruses inactivation as a function of temperature and relative humidity. A total of 102 D values (i.e., the time to obtain a log10 reduction of virus infectivity), including values for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were collected from 26 published studies. The values obtained from the different coronaviruses and studies were found to be generally consistent. Five different models were fitted to the global data set of D values. The most appropriate model considered temperature and relative humidity. A spreadsheet predicting the inactivation of coronaviruses and the associated uncertainty is presented and can be used to predict virus inactivation for untested temperatures, time points, or any coronavirus strains belonging to Alphacoronavirus and Betacoronavirus genera. IMPORTANCE The prediction of the persistence of SARS-CoV-2 on fomites is essential in investigating the importance of contact transmission. This study collects available information on inactivation kinetics of coronaviruses in both solid and liquid fomites and creates a mathematical model for the impact of temperature and relative humidity on virus persistence. The predictions of the model can support more robust decision‐making and could be useful in various public health contexts. A calculator for the natural clearance of SARS-CoV-2 depending on temperature and relative humidity could be a valuable operational tool for public authorities.

Occurrence of poly(hydroxyalkanoate) in the gut homogenate of a phylogenetically higher termite: Macrotermes carbonarius

2008 ◽  
Vol 86 (6) ◽  
pp. 512-515 ◽  
Author(s):  
Kumar Sudesh ◽  
Bee-Yong Tay ◽  
Chow-Yang Lee
Keyword(s):  
Spectroscopic Analysis ◽  
Nile Blue ◽  
Carbon Sources ◽  
Chromatography Analysis ◽  
H Nmr ◽  
Gas Chromatography Analysis ◽  
Termite Gut ◽  
First Time ◽  
Macrotermes Carbonarius ◽  
Gut Homogenate

Gas chromatography analysis of a phylogenetically higher termite-gut homogenate detected the presence of trace amounts of poly(3-hydroxybutyrate) (PHB), a prokaryotic storage material. In addition, the gut homogenate smear, stained with Nile blue A, also suggested the presence of PHB-like granules. Chloroform extracts of both soldier and worker classes of this termite were obtained for further spectroscopic analysis. FTIR, 1H NMR, and 2D 1H-1H NMR analyses confirmed the presence of PHB in both the chloroform extracts. This showed for the first time the occurrence of bacteria capable of accumulating PHB in the termite gut. The results indicated that the physiological environment in the termite gut is suitable for the colonization by PHB-producing bacteria and is probably rich in organic carbon sources, which can be readily assimilated and stored as PHB.Key words: Macrotermes carbonarius, poly(hydroxyalkanoate), PHB, termite

scholarly journals Molecular Assay on Detection of Crimean Congo Hemorrhagic Fever (CCHF) Virus in Ixodid Ticks Collected from Livestock in Slaughterhouse from South of Iran

2020 ◽  
Author(s):  
Mostafa Salehi-Vaziri ◽  
Hassan Vatandoos ◽  
Alireza Sanei-Dehkordi ◽  
Mehdi Fazlalipour ◽  
Mohammad Hassan Pouriayevali ◽  
...  
Keyword(s):  
Tick Infestation ◽  
Hemorrhagic Fever ◽  
The Body ◽  
Ixodid Ticks ◽  
Public Health Issue ◽  
Hard Tick ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hard Ticks ◽  
Slaughter House ◽  
Cchf Virus

Background: Ticks are vectors of a wide variety of pathogens that can be transmitted to humans, and tick-borne diseas­es are a significant public health issue worldwide. The present study was carried out on the hard tick infestation of live­stock transported to Rafsanjan slaughter house in the southeast of Iran. Methods: A cross-sectional survey was carried out biweekly from April to September 2016 to determine tick infesta­tion of the meat-producing animals. All the livestock included in our study were thoroughly inspected for the presence of hard ticks on different parts of their bodies. Results: A total of 258 hard ticks were collected from the body of livestock hosts. The ticks that were sampled were classified into two genera and five species: Hyalomma marginatum, Hy. anatolicum, Hy. asiaticum, Hy. dromedarii, and Rhipicephalus sanguineus. Hyalomma dromedarii was the most abundant species in the study area. More than 50 per­cent of the sampled ticks were collected from the body of camels brought to the slaughter house however molecular analysis showed no Crimean Congo Hemorrhagic Fever (CCHF) virus infection in tick specimens. The Sex ratio of the sampled hard ticks shows that female tick infestation was more common among the study livestock. Conclusion: Due to the crucial role of hard ticks in the transmission of different pathogens to humans, additional inves­tigations are necessary to determine the risk of consumption of infested meat-producing animals in the study area.

scholarly journals Emerging diseases: Crimean-Congo hemorrhagic fever

2004 ◽  
Vol 57 (9-10) ◽  
pp. 453-456 ◽  
Author(s):  
Nada Kuljic-Kapulica
Keyword(s):  
Eastern Europe ◽  
Central Asia ◽  
Hemorrhagic Fever ◽  
Emerging Diseases ◽  
Control Measures ◽  
Ixodid Ticks ◽  
Sub Saharan Africa ◽  
Antibody Detection ◽  
Crimean Congo Hemorrhagic Fever ◽  
Cchf Virus

Introduction Recognized for many years in central Asia and Eastern Europe, Crimean-Congo hemorrhagic fever (CCHF) is a severe zoonotic disease which affects people coming into contact with livestock or ticks. The range of the CCHF virus is now known to extend form central Asia to India, Pakistan, Afghanistan, Iran, Iraq, the Middle East, Eastern Europe, and to most of Saharan and sub-Saharan Africa. Etiology CCHF virus is a member of the Bunyavirus family, and is classified as a Nairovirus. Clinical features After an incubation period of approximately 3 to 6 days the abrupt onset of acute febrile illness occurs. The first symptoms are similar to severe influenza and include fever, headache, severe back and abdominal pain. The hemorrhagic fever manifestations occur after several days of illnesses and include petechial rash, ecchymoses, hematemmesis, and melenna. Cases typically present with some form of hepatitis. The mortality rate is 10-50% in different outbreaks with deaths typically occurring during the second week of illness. Epidemiology The genus Hyalomma of ixodid ticks is the most important vector of the CCHF virus. Vertebrates including birds and small animals provide excellent amplifier hosts of both the virus and the tick. The virus can be transmitted to humans by direct contact with infected animals and from person to person. Diagnosis Early diagnosis is possible in special laboratories using antigen detection by imunofluorescence or ELISA tests or molecular methods as PCR and antibody detection. Control Tick control measures need to be emphasized and utilized to prevent CCHF. This includes spraying camp sites, clothing and danger areas with acaricides or repellent. Strict isolation of patients with CCHF and a focus on barrier nursing would help to prevent nosocomial spread. Presently the vaccine is a dangerous mouse brain-derived version. Future development of a vaccine would help to prevent human infection.

Effects of Ethanol on the NMR Characteristics of Rat Brain

1989 ◽  
Vol 155 (6) ◽  
pp. 818-821 ◽  
Author(s):  
J. A. O. Besson ◽  
S. G. Greentree ◽  
M. A. Foster ◽  
J. E. Rimmington
Keyword(s):  
Water Content ◽  
Bound Water ◽  
Nmr Relaxation ◽  
Chronic Administration ◽  
Ethanol Exposure ◽  
Acute Administration ◽  
H Nmr ◽  
Water State ◽  
Transient Rise ◽  
Membrane Changes

In rats, neither acute administration of ethanol nor the establishment of ethanol dependence by chronic administration for 28 days produced significant 1H-NMR relaxation changes. However, chronic ethanol intake for six months produced a transient rise in T1, with no change in T2 or water content. The significance of these results for study in man is discussed and a hypothesis is proposed to explain discrepant differences between T1, T2 and water content. It is suggested that T1 change with long-term ethanol exposure is related to altered free/bound water state secondary to cell membrane changes.

scholarly journals 25-Hydroxycholesterol Inhibition of Lassa Virus Infection through Aberrant GP1 Glycosylation

mBio ◽  
2016 ◽  
Vol 7 (6) ◽  
Author(s):  
Punya Shrivastava-Ranjan ◽  
Éric Bergeron ◽  
Ayan K. Chakrabarti ◽  
César G. Albariño ◽  
Mike Flint ◽  
...  
Keyword(s):  
Cholesterol Biosynthesis ◽  
Hemorrhagic Fever ◽  
Lassa Fever ◽  
Health Concern ◽  
Virus Infectivity ◽  
Lassa Virus ◽  
Critical Feature ◽  
Course Of Illness ◽  
Enveloped Virus ◽  
Alpha Dystroglycan

ABSTRACT Lassa virus (LASV) infection is a major public health concern due to high fatality rates and limited effective treatment. The interferon-stimulated gene cholesterol 25-hydroxylase ( CH25H ) encodes an enzyme that catalyzes the production of 25-hydroxycholesterol (25HC). 25HC is involved in regulating cholesterol biosynthesis and has recently been identified as a potent antiviral targeting enveloped virus entry. Here, we show a previously unrecognized role of CH25H in inhibiting LASV glycoprotein glycosylation and the production of infectious virus. Overexpression of CH25H or treatment with 25HC decreased LASV G1 glycoprotein N -glycan maturation and reduced the production of infectious LASV. Depletion of endogenous CH25H using small interfering RNA (siRNA) enhanced the levels of fully glycosylated G1 and increased infectious LASV production. Finally, LASV particles produced from 25HC-treated cells were found to be less infectious, to incorporate aberrantly glycosylated GP1 species, and to be defective in binding alpha-dystroglycan, an attachment and entry receptor. Our findings identify a novel role for CH25H in controlling LASV propagation and indicate that manipulation of the expression of CH25H or the administration of 25HC may be a useful anti-LASV therapy. IMPORTANCE Lassa fever is an acute viral hemorrhagic fever in humans caused by Lassa virus (LASV). No vaccine for LASV is currently available. Treatment is limited to the administration of ribavirin, which is only effective when given early in the course of illness. Cholesterol 25-hydroxylase ( CH25H ) is a recently identified interferon-stimulated gene (ISG); it encodes an enzyme that catalyzes the production of 25-hydroxycholesterol (25HC), which inhibits several viruses. Here, we identify a novel antiviral mechanism of 25HC that is dependent on inhibiting the glycosylation of Lassa virus (LASV) glycoprotein and reducing the infectivity of LASV as a means of suppressing viral replication. Since N-linked glycosylation is a critical feature of other enveloped-virus glycoproteins, 25HC may be a broad inhibitor of virus infectivity.

Sign in / Sign up

Export Citation Format

Share Document