Crimean-Congo haemorrhagic fever cases in Turkey

An Investigation of the Relationship Between the Severity Scoring Index and Laboratory Parameters in Pediatric Patients with Crimean-Congo Hemorrhagic Fever: A 12-Year Retrospective Evaluation

Background: There are limited studies on the severity of Crimean-Congo hemorrhagic fever (CCHF) in children. The study aimed to investigate the correlation between the severity scoring index (SSI) score and other laboratory parameters in children. Materials and Methods: Patients younger than 18 years of age who were diagnosed with CCHF in 2011-2022 were included in the study. The SSI score and laboratory parameters at the time of admission were taken into consideration. Results: At 12-year follow-up, 81 pediatric patients were diagnosed with CCHF. According to the SSI calculated at the time of admission, 59 (72.8%) patients were in the mild group and 22 (27.2%) patients were in the moderate group. According to Spearman's correlation analysis results, a positive correlation was found between the SSI score and c-reactive protein (CRP) (r = 0.737, p < 0.001), lactate dehydrogenase (r = 0.312, p = 0.010), alanine transaminase to lymphocyte ratio (r = 0.428, p < 0.001), neutrophil to lymphocyte ratio (r = 0.406, p < 0.001), and derived-neutrophil lymphocyte ratio (r = 0.389, p < 0.001). In addition, lymphocyte to c-reactive protein ratio (LCR) (r = -0.782, p < 0.001), lymphocyte count (r = -0.422, p < 0.001), and white blood cell (r = -0.250, p = 0.026) values were negatively correlated with the SSI. Conclusions: A strong correlation (r > 0.7) was found between LCR (r = -0.782) and CRP (r = 0.737) and the SSI.

Methylene-tetrahydrofolate reductase gene C677T and A1298C polymorphisms as a risk factor for Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a deadly viral disease. Methylene-tetrahydrofolate reductase (MTHFR) has an important role in folate metabolism, and also in the formation of new cells, DNA synthesis, repair and methylation. We aimed to examine the relationship between MTHFR gene C677T (Ala222Val, rs1801133) and A1298C (Glu429Ala, rs1801131) polymorphisms with CCHF in a Turkish population. Totally 273 participants were included in the current study. One hundred forty-one participants were CCHF patients and one hundred thirty-two participants were healthy controls. The polymerase chain reaction (PCR) and further restriction fragment length polymorphism (RFLP) assays were applied to determine the genotypes of MTHFR polymorphisms. We did not find any differences between the CCHF patients and healthy controls in terms of allele and genotype distributions of both the C677T and A1298C polymorphisms. In composite genotype analysis between different groups, the frequency of CT-AA composite genotype, which is formed by C677T-A1298C polymorphisms, was found to be significantly higher in Mild CCHF patients compared to both Severe CCHF patients and controls (p = 0.036 and p = 0.008, respectively). In conclusion, in this study, we found a relationship between CCHF and MTHFR gene polymorphisms. CT-AA composite genotype of MTHFR gene C677T and A1298C polymorphisms showed a predisposition to Mild CCHF.

Crimean-Congo haemorrhagic fever-induced liver injury: A systematic review and meta-analysis

BACKGROUND

Crimean-Congo haemorrhagic fever (CCHF) is a fatal acute tick-borne viral infection and substantial emerging global public health threat. This illness has a high case fatality rate of up to 40%. The liver is one of the important target organs of the CCHF virus.

OBJECTIVE

The aim of this meta-analysis to evaluate the correlation between CCHF and liver injury and draw more generalised inferences about the abnormal serum markers of liver injury such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) in CCHF patients.

METHODS

A literature search was accomplished for published eligible articles with MEDLINE/PubMed and Embase databases. All eligible observational studies and case series were included from around the world. The inclusion criteria were articles describing liver injury biomarkers amongst patients diagnosed with CCHF.

RESULTS

Data from 18 studies, consisting of 1238 patients with CCHF were included in this meta-analysis. Overall pooled incidence of at least one raised liver injury biomarker was 77.95% (95% CI, I²  =  88.50%, P < .0001). Similarly, pooled incidence of elevated AST and ALT was 85.92% (95% CI, I²  = 85.27%, P < .0001) and 64.30% (95% CI, I²  =  88.32%, P < .0001), respectively. Both Egger and Begg-Mazumdar's tests detected no apparent publication bias in all three meta-analyses (P > .05).

CONCLUSION

Our study shows that CCHF has a very detrimental effect on liver function. Abnormal liver function may lead to poor prognosis and increased morbidity and mortality in CCHF patients. Hence, Physicians must recognise and continuously monitor these biomarkers, since these markers may aid in early stratification of prognosis and the prevention of severe outcomes in infection with such a high case fatality rate.

The tick fauna in Istanbul, Turkey, from 2013 to 2017 and identification of their pathogens by multiplex PCR: an epidemiological study

Ticks may carry several pathogens as vectors and their pathogen load may vary due to differences in geography, climate and vegetation. In this study, we collected ticks from 39 districts of Istanbul (Turkey) between May and October, from 2013 to 2017, and identified them under stereo-microscope. In addition, we investigated the pathogens that the ticks carry (Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Rickettsia sp. and Babesia sp.) by using multiplex polymerase chain reaction (PCR) method. We collected a total of 875 ticks from the ground and from various animals and kept them at 4 °C until experiments. We identified 248 Rhipicephalus bursa (28.3% of the total), 205 (23.4%) Rhipicephalus annulatus, 197 (22.5%) Haemaphysalis concinna, 149 (17.0%) Rhipicephalus sanguineus, 24 (2.7%) Hyalomma marginatum, 21 (2.4%) Ixodes ricinus, 13 (1.5%) Rhipicephalus kohlsi, 5 (0.6%) Hyalomma anatolicum, 5 (0.6%) Hyalomma aegyptium, 5 (0.6%) Dermacentor niveus and 3 (0.3%) Ixodes hexagonus. We included a total of 328 questing ticks in the study: 63 R. bursa, 63 R. sanguineus, 63 R. annulatus, 63 H. concinna, 24 H. marginatum, 21 I. ricinus, 13 R. kohlsi, 5 H. anatolicum, 5 H. aegyptium, 5 D. niveus and 3 I. hexagonus. Multiplex PCR indicated that 80 (24.4%) ticks were infected with Rickettsia sp., 5 (1.5%) with B. burgdorferi and 1 (0.3%) with Babesia sp. Our study indicated that Rickettsia is more common in ticks collected around Istanbul.

New aspects about Crimean-Congo hemorrhagic fever (CCHF) cases and associated fatality trends: A global systematic review and meta-analysis

Crimean-Congo hemorrhagic fever (CCHF) is the most popular tick-borne disease causing by Crimean-Congo hemorrhagic fever virus (CCHFV). There are several valuable reviews considering some fields of the CCHF aspects. While there is no a systematic review about means and trends of CCHF cases and fatality rate, means and trends of CCHF cases and fatality rates of human occupations involved in CCHF. Therefore, this meta-analysis review performed to highlight and provide a global detailed of the above CCHF aspects. Among 398 collected papers, 173 papers were become this meta-analysis review. The study results confirm that an apparent increasing CCHF cases occurred through the past decades. The trends of annually and periodically CCHF cases and fatality rates were also increased. The means of annually and periodically CCHF cases and fatality rates were 57 and 432 cases, and 10 cases and 32.2 % and 49 cases and 28.8 %, respectively. The means of annually and periodically CCHF fatality rates are about one-tenth of CCHF human cases. The mean of CCHF fatality rates in Africa (22.0 %) is lower than Asia (33.5 %) and Europe (33.8 %). Among occupations involved in CCHF, agricultural (28.9 %), health-care (19.2 %) and slaughterhouse (16.7 %) workers, and farmers (13.9 %) had the maximum CCHF fatality rates in order. Based on literature review of CCHFV S-segment aspects, several clades and genotypes are reported to distribute in Africa, Asia and Europe regions. There are very wide fields to investigate the epidemiology characteristics of CCHFV clades, genotypes and their distribution in the future.

Crimean-Congo hemorrhagic fever: An update

Crimean-Congo hemorrhagic fever (CCHF) is a severe form of hemorrhagic fever caused by a virus of the genus Nairovirus. The amplifying hosts are various mammal species that remain asymptomatic. Humans are infected by tick bites or contact with animal blood. CCHF has a broad geographic distribution and is endemic in Africa, Asia (in particular the Middle East) and South East Europe. This area has expanded in recent years with two indigenous cases reported in Spain in 2016 and 2018. The incubation period is short with the onset of symptoms in generally less than a week. The initial symptoms are common to other infectious syndromes with fever, headache, myalgia and gastrointestinal symptoms. The hemorrhagic syndrome occurs during a second phase with sometimes major bleeding in and from the mucous membranes and the skin. Strict barrier precautionary measures are required to prevent secondary and nosocomial spread. CCHF may be documented by PCR detection of the virus genome during the first days after the onset of illness, and then by serological testing for IgM antibodies as from the 2nd week after infection. Patient management is mainly based on supportive care. Despite a few encouraging retrospective reports, there is no confirmed evidence that supports the use of ribavirin for curative treatment. Nevertheless, the World Health Organization continues to recommend the use of ribavirin to treat CCHF, considering the limited medical risk related to short-term treatment. The prescription of ribavirin should however be encouraged post-exposure for medical professionals, to prevent secondary infection.

Effects of Paraoxonase-1 variants on course of severity and mortality of Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is an acute viral hemorrhagic fever caused by Crimean Congo hemorrhagic fever virus (CCHFV). Paraoxonase-1 (PON1) is a high density lipoprotein (HDL)-binding protein which defense the body against oxidative stress. To investigate the role of the PON1 gene in CCHF, we screened the genotypes of two single nucleotide polymorphisms (Q192R [rs662] and L55M [rs854560]) in CCHF patients stratified according to course of severity and mortality by using PCR-based RFLP assay. Overall, 132 patients diagnosed as CCHF were enrolled in this study. The frequencies of the three genotypes and two alleles of Q192R and L55M polymorphisms didn't show any statistically significant differences in terms of mortality and disease severity (p > 0.05). Any statistically significant differences were not found between severe and mild and fatal and non-fatal CCHF patients according to seven composite genotypes (p > 0.05). When we analyzed the clinical characteristics of CCHF patients stratified according to PON1gene polymorphisms, any statistically significant differences were not also observed (p > 0.05). Our study showed no possible association between genotypes of PON1 gene Q192R and L55M polymorphisms and CCHF.

Seroprevalence of Crimean-Congo Hemorrhagic Fever in Turkey's Van Province

Crimean-Congo hemorrhagic fever (CCHF) is an endemic tick-borne viral disease that affects both animals and humans. This study aims to determine the seroprevalence of CCHF in Turkey's Van province using analysis of blood samples obtained from people living in the region. Blood specimens were taken from healthy subjects living in Van province and some of the surrounding villages between January and July 2012. Blood samples were initially tested using a CCHF virus (CCHFV) IgM IgG kit for anti-CCHFV IgG, followed by anti-CCHFV IgM determination of any IgG positive blood samples. IgM-positive specimens were re-confirmed using real-time polymerase chain reaction (qPCR). One hundred and 7 men and 261 women were included in the study. Fifty-three blood specimens (14.4%) were anti-CCHFV IgG positive, and 2 of these were anti-CCHFV IgM positive. Two blood samples with anti-CCHFV IgM seropositivity tested negative using qPCR, indicating chronic infections. Locality, sex, and a history of tick bites did not significantly affect anti-CCHFV IgG seropositivity. Although the incidence of anti-CCHFV IgG in blood specimens was 14.4%, no deaths have yet been reported in Turkey's Van province. It is imperative that clinical CCHFV tests be implemented for people at high risk of developing CCHFV-related complications.

Seroprevalence of Crimean-Congo Hemorrhagic Fever Virus in Erzincan Province, Turkey, Relationship with Geographic Features and Risk Factors

To determine the seroprevalence and risk factors associated with Crimean-Congo hemorrhagic fever virus (CCHFV) in residents of Erzincan, Turkey. Although CCHFV is endemic in Erzincan, this is the first study to evaluate its seroprevalence in this region. This study included a total of 372 subjects, 174 of whom had been exposed to or bitten by ticks, 145 of whom worked with livestock, and 53 of whom resided in the city and did not have exposure to livestock. Data on CCHFV IgG and IgM antibodies were extracted from serum samples collected from all subjects using an ELISA. All samples were tested for CCHFV IgG and CCHFV IgM. Only IgM-positive samples were processed for detection of viral RNA through RT-PCR. Using seropositive cases only, we performed spatial analyses to evaluate correlations between seroprevalence and geographic location (i.e., proximity to rivers, altitude, and slope angle of land). In this study, 14.0% (52/322) of the total subjects were positive for CCHFV IgG. Seven of the individuals were positive both for CCHFV IgG and CCHFV IgM. Of these seven, only one sample tested positive for CCHFV RNA. Individuals who worked with livestock in the rural areas and had a history of tick exposure were statistically more likely to test positive for CCHFV IgG than individuals from the city and not exposed to ticks (p < 0.05). Seroprevalence was affected by geographic characteristics, including distance to rivers, altitude, and slope angle of land. We observed a high seroprevalence of CCHFV in Erzincan, which is similar to that observed in other endemic regions of Turkey. CCHFV seroprevalence rates are found to be quite high in the people who live in the sloping fields at certain heights and where there are a lot of rivers and streams.

Knowledge levels regarding crimean-congo hemorrhagic Fever among emergency healthcare workers in an endemic region

Background

In this study, we aimed to determine knowledge levels regarding Crimean-Congo hemorrhagic fever (CCHF) among emergency healthcare workers (HCWs) in an endemic region.

Methods

A questionnaire form consisting of questions about CCHF was applied to the participants.

Results

The mean age was 29.6 ± 6.5 years (range 19 - 45). Fifty-four (49.5%) participants were physicians, 39 (35.8%) were nurses and 16 (14.7%) were paramedics. All of the participants were aware of CCHF, and 48 (44%) of them had previously followed CCHF patients. Rates of the use of protective equipment (masks and gloves) during interventions for patients who were admitted to the emergency service with active hemorrhage were 100% among paramedics, 76.9% among nurses and 61.1% among physicians (P = 0.003). Among 86 (78.9%) HCWs who believed that their knowledge regarding CCHF was adequate, 62 (56.9%) declared that they would prefer not to care for patients with CCHF (P = 0.608).

Conclusions

The use of techniques to prevent transmission of this disease, including gloves, face masks, face visors and box coats, should be explained to emergency room HCWs, and encouragement should be provided for using these techniques.

Characteristics of patients admitted to the emergency department due to tick bite

Crimean-Congo haemorrhagic fever (CCHF) is a tick-borne disease endemic in Turkey since 2002. Çorum is one of the leading five cities in Turkey in which CCHF disease is seen most. We studied characteristics of the patients with tick bites in our emergency department (ED) and determined the fatality rate of the disease in city of Çorum for the first time. We retrospectively analysed the characteristics of the patients admitted to our ED from the medical files of 21,680 patients in a 5-year period. The number of patients with definite diagnosis and who have died was determined. Our results demonstrated that the fatality rate of CCHF in Çorum is 6.78%. Among 21,680 patients, blood samples of 970 patients were sent to an advanced centre in Ankara for polymerase chain reaction (PCR) testing. Results of 560 patients were reported to be PCR (+) and 38 of them have died.

Seroprevalence and risk factors of Crimean-Congo hemorrhagic fever in selected seven provinces in Turkey

Turkey has been one of the most endemic regions since 2002, when Crimean-Congo hemorrhagic fever emerged worldwide. The aim of the present study was to estimate the seroprevelance of CCHF virus in humans who reside in rural and urban areas of known endemic and nonendemic selected provinces of Turkey by using commercial ELISA kit. CCHFV IgG antibodies were detected in 2.3% of the population. The most important risk factors for CCHF seropositivity, were older age, male gender, illiterate, farmer, animal husbandry, living in rural residence in adobe houses, and a previous tick bite history.

Epidemiologic features and risk factors of Crimean-Congo hemorrhagic fever in Samsun province, Turkey

Background

Crimean–Congo hemorrhagic fever (CCHF) is a tick-borne infectious disease that has a considerable mortality risk and is a challenge for the population of endemic rural areas and health care workers. This study investigated the epidemiologic features and main risk factors of CCHF in Samsun Province, Turkey, using CCHF cases diagnosed from 2007 to 2011 recorded by the Samsun Provincial Health Directorate.

Methods

In the study area, 126 cases were evaluated statistically and spatially. Minitab 16 software was used for statistical analysis of the data, and ArcGIS 9.3 software was used for spatial analysis.

Results

Among those who received a diagnosis of CCHF, 69 (54.7%) were male, 57 (45.3%) were female, 114 (90.5%) were discharged, and 12 (9.5%) died. A total of 112 of the 126 (88.9%) cases occurred at an altitude higher than 600 m. In addition, 84.1% of cases were reported during May through July, which are the busiest months for those working in the agriculture and animal husbandry sectors.

Conclusions

CCHF causes severe disease and has a high mortality rate (about 10% in Turkey). Early diagnosis of CCHF can be improved by periodic education of people at high risk, ie, men and women working in agriculture and animal husbandry in rural areas and those working in health care.

Pediatric cases of Crimean-Congo hemorrhagic fever in Turkey

BACKGROUND

The aim of the present study was to identify the epidemiological, clinical and laboratory features of Crimean-Congo hemorrhagic fever (CCHF) virus infection in children.

METHODS

Fifty children infected with CCHF virus in 2005-2010, and hospitalized in the Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital in Ankara, were included. All the patients had positive IgM and/or polymerase chain reaction for CCHF virus.

RESULTS

Of the 50 patients, 19 were female and 31 were male. Patients were between 8 months and 15 years of age. The majority (82%) of patients had a history of tick bite. Fever (100%), hemorrhagic symptoms (76%), nausea-vomiting (60%), tonsillopharyngitis (50%), malaise (50%), myalgia (46%) and maculopapular rash (24%) were the most common presenting clinical features. Mean platelet count on admission was 110,880/mm(3) , and the lowest was 7000/mm(3) . The mean of the lowest white blood cell count was 2860/mm(3) . Other pathological laboratory findings (asparate aminotransferase, alanine aminotransferase, lactate dehydrogenase and creatine kinase) were elevated, and prothrombin time and activated partial thromboplastin time were prolonged. Twenty-three patients (46%) were given ribavirin. No side-effect of ribavirin was seen. No patient died because of CCHF disease.

CONCLUSION

CCHF virus infections are seen mostly in boys and school children and the adolescent age group. Tick bite is the major risk factor. Fever and hemorrhage are the most frequent presenting symptoms. Tonsillopharyngitis and rash on face or body are probably the most remarkable clinical findings in this disease. The CCHF disease course in Turkey may be mild in children.

Species diversity of ixodid ticks feeding on humans in Amasya, Turkey: seasonal abundance and presence of Crimean-Congo hemorrhagic fever virus

Ticks (Acari:Ixodidae) are important pests transmitting tick-borne diseases such as Crimean-Congo hemorrhagic fever (CCHF) to humans. Between 2002 and 2009, numerous CCHF cases were reported in Turkey, including Amasya province. In the current study, species diversity, seasonal abundance of ticks, and presence of CCHF virus (CCHFV) in ticks infesting humans in several districts of Amasya province were determined. In the survey, a total of 2,528 ixodid ticks were collected from humans with tick bite from April to November 2008 and identified to species. Hyalomma marginatum (18.6%), Rhipicephalus bursa (10.3%), Rhipicephalus sanguineus (5.7%), Rhipicephalus (Boophilus) annulatus (2.2%), Dermacentor marginatus (2.5%), Haemaphysalis parva (3.6%), and Ixodes ricinus (1.6%) were the most prevalent species among 26 ixodid tick species infesting humans in Amasya province. Hyalomma franchinii Tonelli & Rondelli, 1932, was a new record for the tick fauna of Turkey. The most abundant species were the members of Hyalomma and Rhipicephalus through summer and declined in fall, whereas relative abundances of Ixodes and Dermacentor ticks were always low on humans in the province. Of 25 Hyalomma tick pools tested, seven pools were CCHFV positive by reverse transcription-polymerase chain reaction. Results indicated diversity of ixodid tick species infesting humans was very high, abundance of ticks changed by season, and ticks infesting humans had potential for transmitting CCHFV.

Crimean-Congo hemorrhagic fever in children

Background

Crimean-Congo hemorrhagic fever (CCHF) virus causes a severe disease in humans with a mortality up to 30%. In Turkey there has been an increase in the number of cases during years since 2002. Humans of all ages living in endemic areas,especially those who are working as shepherds and toddlers, have high risk of acquiring CCHF.

Objectives

The epidemiological, clinical, and laboratory characteristics of the children, who were diagnosed as Crimean-Congo hemorrhagic fever (CCHF) were described.

Study design

The children infected with CCHF virus between April 2008 and October 2009, and hospitalised in Ankara Dışkapı Children's and Research Hospital were included.

Results

Laboratory diagnosis was set by detection of CCHF IgM antibodies and/or genetic detection of CCHF virus. Thirtyone cases included to the study, and all were from the northeastern Anatolia and the southern parts of Black sea region. The mean age was 9.45 ± 4.9 years, the proportion of females was 38.7%. The majority (87%) of the cases had the history of tick bite. There was no fatal case. All the patients had the history of fever. Malaise,tonsillopharyngitis, nausea-vomiting, headache, diarrhea, myalgia and rash were the most common symptoms. The mean AST and ALT levels on the admission were 116 (range 25–389) and 61 (range 8–180) U/L respectively. The mean platelet count on admission was 125,000/mm³, and the lowest was 23,000/mm³. The mean of the lowest white blood cell count was 2353/mm³ and the mean of the highest lactate dehydrogenase was 861 IU/L.

Conclusions

The clinical course of CCHF among children seems to be milder than in adults. Tonsillopharyngitis is a common symptom among children with CCHF.