scholarly journals Detection of Crimean-Congo Hemorrhagic Fever Virus Markers in Samples of Ixodes Ticks Collected in the Territory of the Republic of Guinea

2019 ◽  
pp. 93-98
Author(s):  
E. V. Naydenova ◽  
K. S. Zakharov ◽  
M. Yu. Kartashov ◽  
D. A. Agafonov ◽  
A. V. Boiko ◽  
...  
Keyword(s):  
Viral Antigen ◽  
Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
Republic Of Guinea ◽  
Cchf Virus ◽  
Ixodes Ticks ◽  
Polymerase Chain ◽  
The Republic ◽  
Available Information ◽  
Positive Results

Objective of the study. This work was carried out to identify markers (antigen and RNA) of CrimeanCongo hemorrhagic fever (CCHF) virus in samples from ticks, collected in all landscape-geographical areas of Guinea: Lower, Middle, Upper and Forest, to obtain up-to-date data on the distribution of the pathogen in the country.Materials and methods. Total of 4276 specimens of 8 species of ticks collected in 2016–2019 in the territory of the Republic of Guinea were studied, which were compiled into 1406 samples. Ectoparasites were collected from livestock animals, dogs, and small mammals. Viral antigen was detected using enzyme immunoassay (ELISA). The presence of RNA of the CCHF virus was determined by reverse transcription polymerase chain reaction (RT-PCR).Results and discussion. As a result of the studies, the antigen of the CCHF virus was detected in 21 samples (1.5 %), and RNA – in 37 (2.6 %). All samples, in which the viral antigen was detected, contained RNA of the CCHF virus. Positive results were obtained in samples from all geographical areas of the country. The main vectors and reservoirs of the pathogen in Guinea are ticks of the species Rh. sanguineus, Rh. geigyi, Rh. annulatus and Am. variegatum. The data obtained confirm the previously available information on the possibility of the pathogen circulation in this region and determine the need for further study of the spread of the CCHF virus in the territory of the Republic of Guinea. 

scholarly journals Genetic Monitoring of Crimean-Congo Hemorrhagic Fever Virus in the South of the European Part of Russia

2012 ◽  
pp. 80-85 ◽  
Author(s):  
A. S. Volynkina ◽  
A. N. Kulichenko
Keyword(s):  
Genetic Variants ◽  
Hemorrhagic Fever ◽  
Nucleotide Sequences ◽  
European Part ◽  
Clinical Samples ◽  
Virus Variant ◽  
Hemorrhagic Fever Virus ◽  
Cchf Virus ◽  
European Part Of Russia ◽  
First Time

Presented are the results of gene-typing of CCHF virus detected in clinical samples from CHF patients from the Stavropol, Rostov and Astrakhan Regions in 2011. For 28 samples determined are nucleotide sequences of the fragments 115–652 (S segment) and fragments 984–1469 (M segment). Philogenetic analysis of these nucleotide sequences demonstrated that typical strains circulated in 2011 in the regions under surveillance, importation of the new genetic variants of the virus did not take place. CCHF virus variant affiliated to the subgroup “Astrakhan-2” was detected in the clinical samples for the first time and characterized for its genome S- and M-segment fragments.

scholarly journals Study of the prevalence of antibodies to some arboviruses in the population of the Republic of Guinea

2021 ◽  
Vol 66 (5) ◽  
pp. 346-353
Author(s):  
E. V. Naidenova ◽  
M. Yu. Kartashov ◽  
K. S. Zakharov ◽  
A. P. Shevtsova ◽  
M. G. Diallo ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Hemorrhagic Fever ◽  
Serum Samples ◽  
African Region ◽  
Republic Of Guinea ◽  
Disease Patterns ◽  
Urgent Task ◽  
The Republic ◽  
Total Structure ◽  
Batai Virus

Introduction. Acute febrile diseases kill more than 250,000 people annually in West Africa. Malaria and typhoid fever traditionally occupy most of the total structure of registered fevers. However, these data do not fully reflect the true overall disease patterns in the West African region. This is due to the fact that diagnosis is mainly based on the clinical signs of the infectious process, suggesting that a certain number of diseases may be caused by arboviruses. The detection of specific antibodies (ABs) to infectious pathogens in the blood sera of residents of a particular area is a reliable indicator of the circulation of these pathogens in a particular territory.The aim of this study was to determine the prevalence of antibodies to a number of arboviruses: Dengue (DENV), West Nile (WNV) (family Flaviviridae), Crimean-Congo hemorrhagic fever (orthonairo)virus (CCHFV), Batai (Batai virus), Bhanja (BHAV) (order Bunyavirales), Chikungunya (CHIKV), and Sindbis (SINV) (family Togaviridae) in the population of the Republic of Guinea.Material and methods. In total, a panel of 2,620 blood serum samples from people living in all landscape and geographical areas of Guinea was collected for the study. Detection of IgG antibodies was performed using an enzyme-linked immunoassay (ELISA).Results. In total, ABs to Batai virus were detected in 144 samples (5.5%), BHAV in 58 (2.2%), WNV in 892 (34.0 %), DENV in 659 (25.2 %), CCHFV in 58 (2.2 %), CHIKV in 339 (12.9 %), and SINV in 52 samples (2.0 %).Discussion. The obtained results indicate serological evidence of the spectrum of arboviruses in the population of all landscape and geographical zones of the Republic of Guinea, confirming their active circulation in this territory.Conclusion. Given the high epidemiological significance of arbovirus infectious diseases, it is an urgent task to continue studying its share in the structure of febrile diseases in the territory of the Republic of Guinea.

scholarly journals Screening studies in the diagnosis of chronic carrier of the causative agent of the typhoid fever among residents of different countries

2020 ◽  
Vol 22 (1) ◽  
pp. 91-94
Author(s):  
L A Kaftyreva ◽  
A A Porin ◽  
N N Ryzhman ◽  
E N Kolosovskaya
Keyword(s):  
Typhoid Fever ◽  
Central Asia ◽  
Russian Federation ◽  
Labor Migrants ◽  
Republic Of Guinea ◽  
The Russian Federation ◽  
Chronic Carriage ◽  
The Republic ◽  
Positive Results ◽  
Vi Antigen

The results of screening studies of chronic carriage of the causative agent of typhoid fever (S. Typhi) among residents of various countries are presented. We studied 810 blood serums, including: 462 from citizens of the Republic of Guinea, 244 from labor migrants who arrived in the Russian Federation from Central Asia, and 104 from residents of St. Petersburg. Antibodies to S. Typhi Vi antigen were determined in the passive hemagglutination reaction as a marker of possible chronic carriage of bacteria. When screening studies of sera of citizens of the Republic of Guinea in 21 (4,5%) cases, a positive result was obtained. The level of antibodies to Vi- antigen above diagnostic was found in 6 (1,3%) sera. In 5 samples, the level of antibodies was 1:80, in one - 1: 160. Positive results in a screening study of the sera of labor migrants were obtained in 24 people. A confirmatory test revealed antibodies to the Vi antigen in the diagnostic titer in 9 sera. Positive results were obtained from 2 (3,64%) citizens of Tajikistan and 7 (4,09%) citizens of Uzbekistan. Antibodies to the S. Typhi Vi antigen were not found in residents of St. Petersburg (citizens of the Russian Federation). A comparable level of possible chronic carriage of typhoid fever was revealed for residents of epidemiologically unfavorable territories (Africa) and labor migrants coming to our country from Central Asia. The chances of the emergence of sources of infection in our country are increasing due to the increase in international contacts, which requires additional preventive measures.

scholarly journals Infection Rate in the Population of Ticks Hyalomma marginatum in the Territory of the Crimean Hemorrhagic Fever (CHF) Natural Focus and Assessment of the Link with the CHF Incidence in the Stavropol Region

2021 ◽  
pp. 140-147
Author(s):  
N. V. Tsapko ◽  
V. M. Dubyansky ◽  
A. Yu. Gazieva ◽  
U. M. Ashibokov ◽  
A. S. Volynkina
Keyword(s):  
Infection Rate ◽  
Hemorrhagic Fever ◽  
Central Research Institute ◽  
Central Research ◽  
Natural Focus ◽  
Hemorrhagic Fever Virus ◽  
Hyalomma Marginatum ◽  
Cchf Virus ◽  
Stavropol Region ◽  
The Individual

Objective of the study was to assess the infection rate in the population of the main CCHF virus vector Hyalomma marginatum and its impact on the CHF incidence in the Stavropol Region.Materials and methods. The data on spontaneous infection of H. marginatum ticks in the territory of the CHF natural focus in the Stavropol Region for the period 2012–2018 are presented. In total, more than 22.000 H. marginatum specimens pooled in 1546 samples were tested. The indication of CCHF virus was performed by PCR method using the reagent set for detecting RNA of the CCHF virus “AmplySens® CCHFV-FL” (produced by Central Research Institute of Epidemiology, Russia). To determine the individual infection rate in pools Beklemishev`s method was used. The data on CCHF incidence and amount of tick-bitten persons are taken from official statistics and Annual Epidemiological Report on CHF Incidence provided by the Rospotrebnadzor Administration in the Stavropol Region for the period of 2012–2018.Results and discussion. RNA of CCHF virus was detected in 161 (10.4 %) out of 1546 pooled ticks. The highest infection rate (20 %) was among nymphs. The infection rate for pooled males of H. marginatum was 11 % and for females – 8.5 %. Circulation of Crimean-Congo hemorrhagic fever virus is confirmed in major part of the Stavropol Region. The average infection rate among H. marginatum population was 1.54 % for the period of 2012–2018, ranging from 0.23 % in 2014 to 2.97 % in 2017. It is established that the level of infection rate among H. marginatum population does not affect the CHF incidence in the Stavropol Region. Probably it is not the number of infected ticks in the population that determines the CHF incidence rate but their abundance.

scholarly journals Differential Cell Line Susceptibility to Crimean-Congo Hemorrhagic Fever Virus

2021 ◽  
Vol 11 ◽  
Author(s):  
Shiyu Dai ◽  
Qiaoli Wu ◽  
Xiaoli Wu ◽  
Cheng Peng ◽  
Jia Liu ◽  
...  
Keyword(s):  
Cell Lines ◽  
Ex Vivo ◽  
Animal Cell ◽  
Hemorrhagic Fever ◽  
Viral Disease ◽  
Permissive Cell ◽  
Hek 293 ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
Cchf Virus

Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne viral disease of global concerns due to the increasing incidence and lack of effective treatments. The causative agent, CCHF virus (CCHFV), has been characterized for years; however, its tropism in cell lines of different host and tissue origins remains unclear. This study characterized the susceptibility of 16 human and 6 animal cell lines to CCHFV. Increased viral load and viral nucleoprotein expression, and productive CCHFV replication were detected in human vascular (HUVEC), renal (SW-13 and HEK-293), hepatic (Huh7), and cerebral (U-87 MG) cell lines, which were considered CCHFV-highly permissive cell lines. Renal cell lines derived from monkey and dog could also support CCHFV replication. This study evaluated the susceptibility of different cell lines to CCHFV and identified CCHFV-permissive cell lines. Our findings raise concerns regarding the use of cell lines in ex vivo studies of CCHFV and may have important implications for further fundamental research, which would promote understanding of CCHFV pathogenesis and transmission, as well as benefit designing strategies for disease prevention and control.

scholarly journals Reverse Genetics for Crimean-Congo Hemorrhagic Fever Virus

2003 ◽  
Vol 77 (10) ◽  
pp. 5997-6006 ◽  
Author(s):  
Ramon Flick ◽  
Kirsten Flick ◽  
Heinz Feldmann ◽  
Fredrik Elgh
Keyword(s):  
Reporter Gene ◽  
Reverse Genetics ◽  
Hemorrhagic Fever ◽  
Eukaryotic Cell ◽  
Health Concern ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
Pol I ◽  
Prophylactic Measures ◽  
Cchf Virus

ABSTRACT The widespread geographical distribution of Crimean-Congo hemorrhagic fever (CCHF) virus (more than 30 countries) and its ability to produce severe human disease with high mortality rates (up to 60%) make CCHF a major public health concern worldwide. We describe here the successful establishment of a reverse genetics technology for CCHF virus, a member of the genus Nairovirus, family Bunyaviridae. The RNA polymerase I (pol I) system was used to generate artificial viral RNA genome segments (minigenomes), which contained different reporter genes in antisense (virus RNA) or sense (virus-complementary RNA) orientation flanked by the noncoding regions of the CCHF virus S segment. Reporter gene expression was observed in different eukaryotic cell lines following transfection and subsequent superinfection with CCHF virus, confirming encapsidation, transcription, and replication of the pol I-derived minigenomes. The successful transfer of reporter gene activity to fresh cells demonstrated the generation of recombinant CCHF viruses, thereby confirming the packaging of the pol I-derived minigenomes into progeny viruses. The system offers a unique opportunity to study the biology of nairoviruses and to develop therapeutic and prophylactic measures against CCHF infections. In addition, we demonstrated for the first time that the human pol I system can be used to develop reverse genetics approaches for viruses in the family Bunyaviridae. This is important since it might facilitate the manipulation of bunyaviruses with cell and host tropisms restricted to primates.

scholarly journals Evidence for recombination in Crimean-Congo hemorrhagic fever virus

2005 ◽  
Vol 86 (8) ◽  
pp. 2333-2338 ◽  
Author(s):  
Alexander N. Lukashev
Keyword(s):  
Phylogenetic Trees ◽  
Hemorrhagic Fever ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
Bootscan Analysis ◽  
Phylogenetic Studies ◽  
Cchf Virus ◽  
L Segment ◽  
Virus Strains ◽  
Multiple Recombination

Crimean-Congo hemorrhagic fever (CCHF) virus has attracted considerable attention recently and a number of phylogenetic studies have been published, based mostly on partial sequences of S and M RNA segments. In this study, available full-length S, M and L segment sequences of CCHF virus were checked for recombination. Similarity plots and bootscan analysis of the S segment suggested multiple recombination events between southern European, Asian and African CCHF virus strains, with additional evidence provided by phylogenetic trees, the hidden Markov model and probabilistic divergence measures methods. No unambiguous signs of recombination were observed for M and L segments; however, the results did not exclude the possibility of this. These findings, coupled with a recent report on reassortment in CCHF virus, suggest caution when assessing CCHF virus phylogeny based on short sequence fragments.

scholarly journals Crimean-Congo Hemorrhagic Fever Virus Genomics and Global Diversity

2006 ◽  
Vol 80 (17) ◽  
pp. 8834-8842 ◽  
Author(s):  
Varough M. Deyde ◽  
Marina L. Khristova ◽  
Pierre E. Rollin ◽  
Thomas G. Ksiazek ◽  
Stuart T. Nichol
Keyword(s):  
Genetic Recombination ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Severe Illness ◽  
Long Distance ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
Individual Segment ◽  
Cchf Virus ◽  
Tree Topologies

ABSTRACT Crimean-Congo hemorrhagic fever (CCHF) is a severe illness with high case fatality that occurs in Africa, Europe, the Middle East, and Asia. The complete genomes of 13 geographically and temporally diverse virus strains were determined, and CCHF viruses were found to be highly variable with 20 and 8%, 31 and 27%, and 22 and 10% nucleotide and deduced amino acid differences detected among virus S (nucleocapsid), M (glycoprotein), and L (polymerase) genome segments, respectively. Distinct geographic lineages exist, but with multiple exceptions indicative of long-distance virus movement. Discrepancies among the virus S, M, and L phylogenetic tree topologies document multiple RNA segment reassortment events. An analysis of individual segment datasets suggests genetic recombination also occurs. For an arthropod-borne virus, the genomic plasticity of CCHF virus is surprisingly high.

scholarly journals Detection of Crimean-Congo hemorrhagic fever virus in blood-fed Hyalomma ticks collected from Mauritanian livestock

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
A. Schulz ◽  
Y. Barry ◽  
F. Stoek ◽  
M. J. Pickin ◽  
A. Ba ◽  
...  
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Hemorrhagic Fever ◽  
Blood Feeding ◽  
Fever Virus ◽  
Gene Marker ◽  
Crimean Congo Hemorrhagic Fever ◽  
Hemorrhagic Fever Virus ◽  
One Step ◽  
Polymerase Chain ◽  
Hyalomma Rufipes

Abstract Background Crimean-Congo hemorrhagic fever virus (CCHFV) belongs to the genus Orthonairovirus (Nairovididae) and is a (re)emerging tick-borne pathogen. It is endemic in most parts of Africa, Asia and southern Europe, and can cause severe hemorrhagic symptoms in humans, with high fatality rates (5–30%). Methods Hyalomma ticks were collected from four different livestock herds (cattle and camels) in Mauritania in 2018. The tick species were determined morphologically and confirmed molecularly by using the cytochrome oxidase 1 gene marker. For the detection of CCHFV, ticks were tested individually by one-step multiplex real-time reverse-transcriptase quantitative polymerase chain reaction. The small segment of all positive samples was sequenced to determine the CCHFV genotype. Results In total, 39 of the 1523 ticks (2.56%) collected from 63 cattles and 28 camels tested positive for CCHFV. Three Hyalomma species were identified. Hyalomma rufipes had the largest proportion of positivity (5.67%; 16/282), followed by Hyalomma dromedarii (1.89%; 23/1214). No Hyalomma impeltatum tested positive (0%; 0/21). Positive ticks were found in only six out of 91 host animals. Viral sequence analysis revealed the presence of two different CCHFV lineages (Africa I and Africa III). Conclusions In this study, 2.56% of Hyalomma ticks collected from camels and cattle in Mauritania tested positive for CCHFV. However, the true prevalence of CCHFV in unfed ticks may be lower, as a considerable number of ticks may have been passively infected during blood-feeding by co-feeding ticks or due to viremia of the host. The results indicate the need to track the actual area of circulation of this virus. Graphic Abstract

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