Analysis of risk-factors among patients with Crimean-Congo haemorrhagic fever virus infection: severity criteria revisited

The aim of this study was to determine the predictors of mortality among patients infected with Crimean-Congo haemorrhagic fever (CCHF) virus. Among patients with acute febrile syndrome, characterised by malaise, bleeding, leukopenia and thrombocytopenia, who were admitted to hospital during the spring and summer of 2002-2004, 54 had positive IgM and/or PCR results for CCHF virus in blood or tissue. The overall case fatality rate was 7.4%. Among the fatalities, haematemesis (p 0.009), melaena (p 0.001) and somnolence (p 0.022) were more common, the median platelet count was significantly lower (10,600/mL vs. 20,000/mL; p 0.038), the mean prothrombin time (27 s vs. 16 s; p 0.002) and mean activated partial thromboplastin time (73 s vs. 44 s; p < 0.001) were longer, and the mean alanine transferase (ALT) level (1,125 vs. 331; p < 0.001), the mean aspartate transferase (AST) level (3,118 vs. 913; p 0.004) and the mean fibrinogen level (119 vs. 340; p 0.012) were higher. Serum IgM and IgG against CCHF virus was detected in 25% and 0%, respectively, of fatal cases, compared with 94% and 62%, respectively, of cases with favourable outcomes. Oral ribavirin was prescribed to 22 (41%) patients. Of the four fatal cases, it was the intention to prescribe ribavirin to three patients, but this was not possible because of haematemesis and melaena. Higher levels of AST (>or= 700 U/L) and ALT (>or= 900 U/L) are suggested for use as severity criteria. Oral ribavirin was not effective for patients with haematemesis, and intravenous ribavirin is necessary for treatment of CCHF.     

A new genetic variant of the Crimean–Congo hemorrhagic fever virus isolated in Crimea

The work presents the results of genetic identification of Crimean–Congo hemorrhagic fever (CCHF) virus isolates obtained in the Crimean federal district in the course of the 2015 epidemiological survey for a Crimean-Congo hemorrhagic fever case from Crimea. A PCR test for the presence of the CCHF virus RNA was performed for a single blood serum sample obtained from a patient and for 61 pools (506 individuals) of ixodic ticks collected during an epizootological study carried out in six administrative regions of the Crimean federal district. CCHF virus RNA was detected in the patient’s blood serum and in ten samples of ixodic ticks. Genetic identification of the CCHF virus isolates was performed by sequencing S, M, and L virus genome segments. The results of the molecular and genetic analysis showed that the RNAs of the CCHF viruses detected in the blood serum samples and three tick suspension samples are highly homologous to each other and belong to a new Crimea (Vd) genetic subgroup of the Europe 1 genotype. Whole genome sequences were obtained for two CCHF virus isolates from the Crimea subgroup (Vd). CCHF virus variants belonging to the Crimea subgroup (Vd) of the Europe 1 genotype have been described for the first time and are endemic for the Crimean peninsula.     

Successful clearance of human parainfluenza virus type 2 viraemia with intravenous ribavirin and immunoglobulin in a patient with acute myocarditis

Human parainfluenza virus (HPIV) infection as an aetiology of acute viral myocarditis is rare, with only few cases reported in the literature to date. Here we report a case of fulminant HPIV-2 myocarditis in a 47 year-old man with viraemia who was successfully treated with intravenous ribavirin and intravenous immunoglobulin (IVIG). There are currently no recommendations on the treatment of HPIV myocarditis. We are, to our knowledge, the first to report a patient with a documented HPIV-2 viraemia that subsequently cleared after the initiation of antiviral therapy. Although it is difficult to definitively attribute the patient's clinical improvement to ribavirin or IVIG alone, our case does suggest that clinicians may wish to consider initiating ribavirin and IVIG in patients with HPIV myocarditis and persistent viraemia not responding to supportive measures alone.     

The role of ribavirin in the therapy of Crimean-Congo hemorrhagic fever: early use is promising

Crimean-Congo hemorrhagic fever (CCHF) is a disease with high fatality. To demonstrate the effectiveness of ribavirin against CCHF. The first group of 21 patients received ribavirin within 4 days of the onset of symptoms (early use of ribavirin, EUR); the second group of 20 patients received ribavirin ≥5 days after the onset of the symptoms of the disease (late use of ribavirin, LUR); and the last group of 11 patients did not receive ribavirin (no use of ribavirin, NUR). At 5–10 days from the onset of symptoms the mean platelet counts of the patients in the EUR group were significantly higher than those of the patients in LUR group, and at 7–9 days, they were significantly higher than that of the patients in the NUR group. The mean aspartate transferase levels in the EUR group were significantly lower than of the NUR group on days 8 and 9, and the mean alanine transferase level was significantly lower on day 8 after the onset of the symptoms. There is a beneficial effect of ribavirin if given at an early phase of the CCHF. We suggest ribavirin use especially in the early phase of the disease.     

The efficacy of ribavirin in the treatment of Crimean-Congo hemorrhagic fever in Eastern Black Sea region in Turkey

BackgroundThe efficiency of ribavirin for treatment of Crimean-Congo hemorrhagic fever (CCHF) is unknown. In the literature, prospective randomized studies investigating the efficacy of ribavirin are not found.ObjectivesTo investigate the efficacy of ribavirin in treatment of patients with CCHF.Study designIn this prospective randomized cohort study 136 cases were included between June 2004 and August 2007. The diagnosis was confirmed in the CCHF reference laboratory of Refik Saydam National Hygiene Central Institute of the Turkish Ministry of Health. Patients either received ribavirin plus supportive treatment (Group A) (n = 64) or only supportive treatment (Group B) (n = 72). For the evaluation of efficacy of ribavirin, various parameters were compared between Group A and Group B.ResultsAs well as the similarity of demographic features between the two groups, there were no statistical differences in incubation time; hospitalization time; patients requiring platelet replacement therapy; the time taken for platelet levels to return to normal levels and mortality. In Group B, the rate of tick contact was higher (p = 0.03). In Group A, leukocyte levels took longer to return to the normal levels (p = 0.02).ConclusionIn our study, there was no positive effect determined on clinical or laboratory parameters in CCHF patients treated with ribavirin, also it was observed that leukocyte levels took longer to return to normal (p = 0.02) and, while not statistically significant, the longer period of hospitalization (p = 0.09) needed was observed as a negative effect. Because of these reasons, it is thought that the use of ribavirin makes no significant contribution to the prognosis of the CCHF disease.     

Emergence of Crimean–Congo haemorrhagic fever in Greece

In the summer of 2008, the first case of Crimean–Congo haemorrhagic fever (CCHF) was observed in Greece. The laboratory diagnosis was established using nested RT-PCR and quantitative real-time RT-PCR. A high viral load and increased levels of cytokines were detected on the third day of illness and the patient died 7 days after the onset of symptoms. Nucleotide sequence analysis revealed that the Greek CCHF virus strain had high sequence identity with other Balkan CCHF virus strains.     

Rapid diagnosis of human Crimean-Congo hemorrhagic fever and detection of the virus in naturally infected ticks.

An enzyme-linked immunosorbent assay (ELISA) was developed to detect Crimean-Congo hemorrhagic fever (CCHF) virus-specific immunoglobulin M (IgM) in human serum samples. For this test, a heat-inactivated antigen was prepared from the brains of suckling mice infected with CCHF virus. The IgM-capture ELISA proved more sensitive than indirect fluorescence tests for IgM to this virus. A human serum containing high-titer IgM to CCHF virus was used for an antigen-capture ELISA to detect this virus in heat-inactivated suspensions of virus-infected ticks. The antigen-capture ELISA appeared to be as sensitive as virus isolation in suckling mice. The studies described suggest that the IgM-capture ELISA and the antigen-detection ELISA should provide a rapid and sensitive diagnosis of human CCHF virus infection and should be useful in ecologic studies of this virus.     

Inhibition of Semliki Forest virus multiplication by ribavirin: a potential method for the monitoring of antiviral agents in serum

An enzyme immunoassay (EIA) to determine 50% inhibitory concentrations of ribavirin which suppresses Semliki Forest virus (SFV) multiplication in L-cells is described. Inhibition of SFV replication by ribavirin was measured by detection of viral glycoprotein, on the surface of infected L-cell monolayers, with a horseradish peroxidase labeled monoclonal antibody with specificity for the E2 glycoprotein of SFV. The concentration of ribavirin in culture fluid associated with 50% reduction of control absorbance values was defined as the 50% inhibitory concentration (IC50). The IC50 of ribavirin measured with EIA was mainly influenced by the multiplicity of infection (MOI). At MOI values of 3, 6 and 12 reduction of absorbance values was already obvious at 4.5 h of infection. Furthermore reduction of absorbance values correlated with inhibition of virus production as determined by plaque titration of culture fluids. When the EIA was used for the determination of active ribavirin in serum from treated animals the drug was detectable 1 h after intravenous administration of 4 mg of ribavirin to a concentration of 8 micrograms per ml serum. The results indicate that this simple EIA is suitable for the monitoring of active antiviral drugs in body fluids.     

Genetic variants of the Crimean-Congo hemorrhagic fever virus circulating in endemic areas of Southern Tajikistan in 2009

Five-hundred-and-six Hyalomma anatolicum ticks were collected and studied in two Crimean-Congo hemorrhagic fever (CCHF) endemic regions of Tajikistan. Antigen and RNA of the CCHF virus were detected in 3.4% of tick pools from the Rudaki district using ELISA and RT-PCR tests. As for the Tursunzade district, viral antigen was identified in 9.0% of the samples and viral RNA was identified in 8.1% of the samples. Multiple alignment of the obtained nucleotide sequences of a region of the S-segment of the genome of the CCHF virus 287 nucleotides in length (996–1282) and the multiple alignment of the deduced amino-acid sequences of the samples carried out to compare with CCHF virus strains from the GenBank database, as well as their phylogenetic analysis, enabled us to conclude that the Asia 1 and Asia 2 genotypes of the CCHF virus are circulating in Tajikistan. It is important to note that the genotype Asia 1 virus was detected in Tajikistan for the first time.     

Differentiation of genetic variants of Crimean-Congo hemorrhagic fever virus

The paper describes a simple, rapid screening of samples potentially containing Crimean-Congo hemorrhagic fever (CCHF) virus strains, by applying the restriction analysis of amplicones, for the differentiation of CCHF virus genotypes that are characteristic of Europe from virus biovariants uncharacteristic of this area, this technique requiring no sequence at the first stage. For this screening, the authors propose to use the PCR fragment of CCHF L segment that comprises a variable region, as well as Alul and Haelll restriction endonucleases. The screening scheme proposed for samples potentially containing CCHF virus may aid investigators to monitor in order to detect uncharacteristic genotypic virus variants in the Russian Federation and other European countries.     

Parotitis associated with Crimean Congo hemorrhagic fever virus

Background

Crimean Congo Hemorrhagic Fever (CCHF) is a potentially fatal tick-borne viral disease, the course of which may accompanied by various clinical findings.

Objectives

We describe a picture of non-suppurative parotitis developing in association with CCHF virus.

Study design

A 48-year-old patient presenting to our hospital with lethargy, hemorrhage and pain and swelling below the left ear was diagnosed with CCHF through IgM antibody and polymerase chain reaction positivity in serum investigated for CCHF virus. A picture of non-suppurative parotitis developed on the 3rd day of admission.

Results

Other causes of parotitis were excluded with the help of serological tests, and the case was regarded as one of CCHF-associated parotitis. The patient was put on adjuvant therapy, an improvement in clinical findings was observed and he was discharged in a healthy condition on the 8th day.

Conclusions

Ours is the first case in the literature of parotitis seen during CCHF. CCHF should be considered in differential diagnosis in addition to other frequently encountered viral agents in patients from endemic regions presenting with a picture of non-suppurative parotitis.     

Colorimetric nucleic acid testing assay for RNA virus detection based on circle-to-circle amplification of padlock probes

We developed a molecular diagnostic method for detection of RNA virus based on padlock probes and colorimetric readout. The feasibility of our approach was demonstrated by using detection of Crimean-Congo hemorrhagic fever (CCHF) virus as a model. Compared with conventional PCR-based methods, our approach does not require advanced equipment, involves easier assay design, and has a sensitivity of 10(3) viral copies/ml. By using a cocktail of padlock probes, synthetic templates representing different viral strain variants could be detected. We analyzed 34 CCHF patient samples, and all patients were correctly diagnosed when the results were compared to those of the current real-time PCR method. This is the first time that highly specific padlock probes have been applied to detection of a highly variable target sequence typical of RNA viruses.     

Genetic analysis of the M RNA segment of Crimean-Congo hemorrhagic fever virus strains in Turkey

Summary Crimean-Congo hemorrhagic fever (CCHF) virus is member of the genus Nairovirus of the family Bunyaviridae. All members of the family Bunyaviridae are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. During recent years, outbreaks have been reported in Turkey. However, little information is available on the genetic diversity of CCHF virus in Turkey. In this study, a total of 1227 adult ticks were collected from domestic ruminants (796 specimens from cattle, 399 specimens from goats and 32 specimens from sheep). The presence of the M segment of CCHF virus was determined in 4 of 40 (10%) Hyalomma marginatum marginatum pools, in 2 of 38 (7.89%) Rhipicephalus bursa pools, and in 1 of 7 (7%) Boophylus annulatus pools. Hyalomma anatolicum anatolicum pools gave negative RT-PCR result against CCHF virus. Serum samples from seven patients infected with CCHF were selected and subjected to RT-PCR to amplify partial M segment of CCHF virus. This report introduces the first data on partial nucleotide sequences of M RNA segments of CCHF virus strains circulating in Turkey, isolated from ticks. Correspondence: Aykut Ozdarendeli, Department of Virology, Firat University College of Veterinary Medicine, 23119 Elazig, Turkey     

Crimean-Congo haemorrhagic fever presenting as epididymo-orchitis

BackgroundCrimean-Congo haemorrhagic fever (CCHF) is a potentially fatal disease caused by a tick-borne virus.ObjectivesA 53-year-old man presented with fever and acute painful scrotal swelling simulating acute epididymo-orchitis.Study designBased on the clinical and epidemiological findings, CCHF virus infection and epididymo-orchitis were suspected. This symptom, rarely reported in viral haemorrhagic fevers, was observed in this case.ResultsThe diagnosis was confirmed by detection of the IgM antibody to CCHF virus and positive RT-PCR.ConclusionWe report the first case of imported CCHF presenting as epididymo-orchitis. This symptom is a rare complication of CCHF, and the clinician should consider this entity in the differential diagnosis of adults with epididymo-orchitis.     

Genomic S segment of Crimean-Congo hemorrhagic fever virus circulating in Russia and Bulgaria

S-segment nucleotide sequences for two Crimean-Congo hemorrhagic fever (CCHF) virus strains isolated in the Rostov Region of Russia and in Bulgaria have been determined. Analysis of complete S-segment nucleotide sequences in the viral strains from different regions of the world has established that the CCHF virus strains isolated from ticks and human beings in different southern Russian regions in 1967 and 2000 are very closely genetically and they form an individual subgroup in the basic European genetic group. By the S-segment structure, the CCHF virus strain isolated in Bulgaria in 1978 belongs to the same genetic group as a representative of its second subgroup. Analysis of the S-segment 3'-noncoding region suggests that the CCHF virus circulating in Europe, Central Asia, and China may have originated from one global focus of infection, including several CCHF virus genovariants. During evolution, fragmental exchange apparently occurred in the S-segment 3'-noncoding region as a result of homological recombination.     

Crimean-Congo hemorrhagic fever in Africa. Apropos of a case with hemorrhagic manifestations in Mauritania

The authors report a case of CCHF observed in a patient living in South Mauritania. This is the first case of an haemorrhagic syndrome due to the CCHF virus in West Africa. Data concerning this disease in Africa are brought up to date.