Development of targeted whole genome sequencing approaches for Crimean-Congo haemorrhagic fever virus (CCHFV).

Crimean-Congo haemorrhagic fever (CCHF) is the most prevalent human tick-borne viral disease, with a reported case fatality rate of 30 % or higher. The virus contains a tri-segmented, negative-sense RNA genome consisting of the small (S), medium (M) and large (L) segments encoding respectively the nucleoprotein (NP), the glycoproteins precursor (GPC) and the viral RNA-dependent RNA polymerase (RDRP). CCHFV is one of the most genetically diverse arboviruses, with seven distinct lineages named after the region they were first reported in and based on S segment phylogenetic analysis. Due to the high genetic divergence of the virus, a single targeted tiling PCR strategy to enrich for viral nucleic acids prior to sequencing is difficult to develop, and previously we have developed and validated a tiling PCR enrichment method for the Europe 1 genetic lineage. We have developed a targeted, probe hybridisation capture method and validated its performance on clinical as well as cell-cultured material of CCHFV from different genetic lineages, including Europe 1, Europe 2, Africa 2 and Africa 3. The method produced over 95 % reference coverages with at least 10x sequencing depth. While we were only able to recover a single complete genome sequence from the tested Europe 1 clinical samples with the capture hybridisation protocol, the data provides evidence of its applicability to different CCHFV genetic lineages. CCHFV is an important tick-borne human pathogen with wide geographical distribution. Environmental as well as anthropogenic factors are causing increased CCHFV transmission. Development of strategies to recover CCHFV sequences from genetically diverse lineages of the virus is of paramount importance to monitor the presence of the virus in new areas, and in public health responses for CCHFV molecular surveillance to rapidly detect, diagnose and characterise currently circulating strains.

Convalescent human plasma candidate reference materials protect against Crimean-Congo haemorrhagic fever virus (CCHFV) challenge in an A129 mouse model.

Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is spread by infected ticks or direct contact with blood, tissues and fluids from infected patients or livestock. Infection with CCHFV causes severe haemorrhagic fever in humans which is fatal in up to 83 % of cases. CCHFV is listed as a priority pathogen by the World Health Organization (WHO) and there are currently no widely-approved vaccines. Defining a serological correlate of protection against CCHFV infection would support the development of vaccines by providing a 'target threshold' for pre-clinical and clinical immunogenicity studies to achieve in subjects and potentially obviate the need for in vivo protection studies. We therefore sought to establish titratable protection against CCHFV using pooled human convalescent plasma, in a mouse model. Convalescent plasma collected from seven individuals with a known previous CCHFV virus infection were characterised using binding antibody and neutralisation assays. All plasma recognised nucleoprotein and the Gc glycoprotein, but some had a lower Gn glycoprotein response by ELISA. Pooled plasma and two individual donations from convalescent donors were administered intraperitoneally to A129 mice 24 h prior to intradermal challenge with CCHFV (strain IbAr10200). A partial protective effect was observed with all three convalescent plasmas characterised by longer survival post-challenge and reduced clinical score. These protective responses were titratable. Further characterisation of the serological reactivities within these samples will establish their value as reference materials to support assay harmonisation and accelerate vaccine development for CCHFV.

[COVID-19 Co-infection in a patient with Crimean Congo Hemorrhagic Fever: A Case Report]. / Kirim Kongo Kanamali Atesi Hastasinda COVID-19 Ko-enfeksiyonu: Bir Olgu Sunumu.

Crimean-Congo Hemorrhagic Fever (CCHF) is an acute viral zoonotic disease. Coronavirus disease-2019 (COVID-19) is a newly emerging viral disease and it is caused by "severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)". In this article, a case diagnosed with CCHF and COVID-19 coinfection confirmed by the polymerase chain reaction (PCR) method and its management was presented. A thirtyfive years old female patient admitted to the hospital with the complaint of fever for one day and common body pain. It was learned that three days before the onset of her complaints, she removed a tick adhering to the anterior abdominal wall with no precaution. Her body temperature was 38°C degrees and her respiratory rate was 22 per minute. The leucocyte count was 3660/mm³ and the platelet count was 138.000/mm³. It was determined that prothrombin time was 15.4 seconds, international normalized ratio (INR) was 1.35 seconds, and D-dimer level was 1310 ng/ml. The patient was hospitalized with prediagnosis of CCHF. Supportive treatment was started. On the second day at the clinical follow-up of the patient, complaints of sore throat and cough without sputum started. A combined nasopharyngeal and throat swab sample was taken from the patient because of the suspicion of COVID-19. COVID-19 PCR test result was reported as positive. Favipiravir treatment was started. The CCHF-PCR test, which was studied from the serum sample sent to the Microbiology Reference Laboratories was reported as positive. From the third day of favipiravir treatment; the patient did not have a fever and her complaints regressed. On the ninth day of her hospitalization, she was discharged. In this case; it is important to show that both diseases, especially in regions where CCHF disease is endemic, can be confused due to the similarity of the clinical picture with COVID-19 and to know that they can coexist.

Comparison of the Predictive Performances of qSOFA, APACHE II, and SGS for Evaluation of the Disease Prognosis of CCHF Patients at the Emergency Department.

In this study, we compared the predictive performances of quick sequential organ failure assessment (qSOFA), the acute physiology and chronic health evaluation (APACHE II) scores, and the severity grading score (SGS) for evaluation of the disease prognosis of patients with Crimean-Congo hemorrhagic fever (CCHF) at the emergency department. We recorded the qSOFA, SGS, and APACHE II scores at admission and at the 72nd and 120th hour in 97 patients admitted to the emergency department and diagnosed with CCHF. In our study, the area under a receiver operating characteristic curve values of qSOFA, SGS, and APACHE II at admission were found to be 0.640, 0.824, and 0.576, respectively. No statistical significance was found for a qSOFA score ≥ 2 at admission as a predictor of mortality. The use of qSOFA score for diseases with a mortal prognosis such as CCHF is insufficient in predicting the prognosis.