Crimean-Congo hemorrhagic fever virus: genetic analysis and tick survey in Turkey

Diversity of hard ticks parasitizing farm animals in the Qarabulli region, Northwestern Libya

Background

There are 26 species of ticks known to exist in Libya. Despite the presence of a number of investigations on ticks in Libya, there are no published studies on ticks in the Al-Qarboulli area.

Aim

The aim of this study was to identify the tick species infesting farm animals in the Qarabulli region.

Methods

Ticks were collected manually on a monthly basis from the examined hosts (cattle, sheep, dogs, and camels) that were selected randomly in the period between July 2021 and June 2022.

Results

A total of 717 ticks were collected on 775 hosts, eight tick species were encountered: Hyalomma excavatum (41.00%), Rhipicephalus sanguineus (23.43%), Hyalomma dromedarii (12.13%), Hyalomma marginatum (9.21%), Hyalomma anatolicum (8.51%), Rhipicephalus annulatus (5.30%), Hyalomma rufipes (0.28%), and Boophilus microplus (0.14%). The mean prevalence of all species was 22.32%. The mean intensity of all species was 0.93 ticks per host. The presence of ticks among the months of the year varied among tick species.

Conclusion

The results showed high tick infestation in farm animals of Qarabulli, Libya, suggesting an increased risk of tick-borne diseases. This highlights the need for preventative measures and public awareness to reduce tick populations. Further studies are recommended to understand the spread of tick-borne diseases in the area.

Perception of Ticks and Tick-Borne Diseases Worldwide

In this comprehensive review study, we addressed the challenge posed by ticks and tick-borne diseases (TBDs) with growing incidence affecting human and animal health worldwide. Data and perspectives were collected from different countries and regions worldwide, including America, Europe, Africa, Asia, and Oceania. The results updated the current situation with ticks and TBD and how it is perceived by society with information bias and gaps. The study reinforces the importance of multidisciplinary and international collaborations to advance in the surveillance, communication and proposed future directions to address these challenges.

Crimean-Congo Hemorrhagic Fever Virus: Progress in Vaccine Development

Crimean-Congo hemorrhagic fever virus (CCHFV), a member of the Nairoviridae family and Bunyavirales order, is transmitted to humans via tick bites or contact with the blood of infected animals. It can cause severe symptoms, including hemorrhagic fever, with a mortality rate between 5 to 30%. CCHFV is classified as a high-priority pathogen by the World Health Organization (WHO) due to its high fatality rate and the absence of effective medical countermeasures. CCHFV is endemic in several regions across the world, including Africa, Europe, the Middle East, and Asia, and has the potential for global spread. The emergence of the disease in new areas, as well as the presence of the tick vector in countries without reported cases, emphasizes the need for preventive measures to be taken. In the past, the lack of a suitable animal model susceptible to CCHFV infection has been a major obstacle in the development of vaccines and treatments. However, recent advances in biotechnology and the availability of suitable animal models have significantly expedited the development of vaccines against CCHF. These advancements have not only contributed to an enhanced understanding of the pathogenesis of CCHF but have also facilitated the evaluation of potential vaccine candidates. This review outlines the immune response to CCHFV and animal models utilized for the study of CCHFV and highlights the progress made in CCHFV vaccine studies. Despite remarkable advancements in vaccine development for CCHFV, it remains crucial to prioritize continued research, collaboration, and investment in this field.

Arthropod vectors of disease agents: their role in public and veterinary health in Turkiye and their control measures

Mosquitoes, sandflies, and ticks are hematophagous arthropods that pose a huge threat to public and veterinary health. They are capable of serving as vectors of disease agents that can and have caused explosive epidemics affecting millions of people and animals. Several factors like climate change, urbanization, and international travel contribute substantially to the persistence and dispersal of these vectors from their established areas to newly invaded areas. Once established in their new home, they can serve as vectors for disease transmission or increase the risk of disease emergence. Turkiye is vulnerable to climate change and has experienced upward trends in annual temperatures and rising sea levels, and greater fluctuations in precipitation rates. It is a potential hotspot for important vector species because the climate in various regions is conducive for several insect and acari species and serves as a conduit for refugees and immigrants fleeing areas troubled with armed conflicts and natural disasters, which have increased substantially in recent years. These people may serve as carriers of the vectors or be infected by disease agents that require arthropod vectors for transmission. Although it cannot be supposed that every arthropod species is a competent vector, this review aims to (1)illustrate the factors that contribute to the persistence and dispersal of arthropod vectors, (2)determine the status of the established arthropod vector species in Turkiye and their capability of serving as vectors of disease agents, and (3)assess the role of newly-introduced arthropod vectors into Turkiye and how they were introduced into the country. We also provide information on important disease incidence (if there's any) and control measures applied by public health officials from different provinces.

The Seroprevalence of Crimean-Congo Hemorrhagic Fever in Wild and Domestic Animals: An Epidemiological Update for Domestic Animals and First Seroevidence in Wild Animals from Turkiye

Simple Summary

Crimean-Congo hemorrhagic fever is a tick-borne and zoonotic emerging viral disease that is characterized by the sudden development of high fever and vascular bleeding in humans. The seroevidence among livestock has been reported, but it is less known in wild animals. Due to the importance and emerging state of the disease, we conducted a serosurvey on both domestic and wild animals in different areas of Turkiye. Serological investigations conducted on cattle, goats, and sheep revealed 10.81%, 15.15%, and 19.23% seropositivity, respectively, in the collected serum samples. We also found seropositivity rates in hare (23.81%) and wild boars (2.5%) indicating the substantial role of wild animals in virus epidemiology in Turkiye. This study provides first seroevidence of Crimean Congo hemorrhagic fever in wild animals in Turkiye.

Abstract

Crimean-Congo hemorrhagic fever virus (CCHFV) is a zoonotic, tick-borne pathogen that is endemic to some parts of Europe, Africa, and Asia. The disease causes fever and hemorrhagic manifestations in humans but not in animals. Domestic and wild animals are asymptomatic hosts of CCHFV and are critical in the transmission cycle. Hyalomma marginatum spp. has been identified as the natural reservoir and vector of the virus in Turkiye. A few studies have been conducted on domesticated animals showing the seroprevalence of CCHFV in them, but seroevidence in wild animals is absent. For contributing this antrum to the understanding of virus transmission in Turkiye, we performed a seroprevalence investigation of CCHFV in both wild and domesticated animals in various geographical areas of Turkiye. In-house IgG iELISA was performed for the screening of sera IgG in a total of 582 animal samples collected from boar (n = 40), cattle (n = 259), goat (n = 132), hare (n = 21), and sheep (n = 130). Results from ELISA performed on domestic animals revealed 10.81%, 15.15%, and 19.23% anti-CCHF virus seropositivity in cattle, goats, and sheep, respectively, in collected serum samples. ELISA tests performed in wild animals showed 23.81% and 2.5% positivity in hare and wild boars, respectively, suggesting the importance of wild animals in CCHF virus epidemiology in Turkiye. This study performed the first serological investigation of CCHFV in wild animals and provided the first seroevidence of CCHFV in wild boars and hare in Turkiye.

Distribution of Tick-Borne Pathogens in Domestic Animals and Their Ticks in the Countries of the Mediterranean Basin between 2000 and 2021: A Systematic Review

Tick-borne pathogens (TBPs) include a wide range of bacteria, parasites and viruses that cause a large spectrum of animal, human and zoonotic tick-borne diseases (TBDs). The object of this review was to establish an inventory and an analysis of TBPs found in domestic animals in the countries of the Mediterranean Basin. This geographic area occupies a central position between several continents and is an area of movement for animals, humans and pathogens of interest and their vectors, which is important in terms of animal and human health. In this systematic review, we included a total of 271 publications produced between 2000–2021 concerning TBPs in domestic animals. Among this literature, we found a total of 90 pathogen species (known as TBPs) reported in the 20 countries of the area; these were detected in tick species from domestic animals and were also directly detected in domestic animals. In all, 31 tick species were recorded and 12 domestic animal species, the latter comprising nine livestock and three pet species. More than 50% of the publications were from Western Europe. Island data were extracted and assessed, as islands of the Mediterranean Basin were represented in 16% of the publications and 77.8% of the TBPs reported. Our results show the importance of islands in the monitoring of TBPs, despite the low percentage of publications.

Species diversity of ticks (Acari: Ixodidae) in Tarhuna, Libya

Background

Twenty-five species of ticks have been recorded in Libya. No systematic studies have been conducted in Tarhuna region regarding tick species that infest livestock.

Aim

To identify the species of ticks that infest livestock in Tarhuna, Libya.

Methods

The study was carried out from August 2015 to May 2016 in Tarhuna, which is located in northwestern Libya. A total of 634 ticks (349 males, 280 females, and 5 nymphs) were collected from 145 randomly selected animals (camels, sheep, and goats). Samples were collected seasonally from different locations.

Results

Four species of ticks were recorded: Hyalomma dromedarii (83.12%), Rhipicephalus bursa (6.94%), Hyalomma excavatum (6.63%), and Rhipicephalus camicasi (3.31%). The mean prevalence of all species was 4.37 ticks/host. All of the tick species were collected from sheep and goats, except H. dromedarii which was collected from camels only. With respect to the season of collection, the number of species varied among seasons; the highest prevalence was in summer (6.53 ticks\host) and the lowest was in spring (2.18 ticks\host). The highest average number of tick species was observed in H. dromedarii (10.13 ticks/host), followed by 1.21 ticks/host in R. camicasi, 1.07 ticks/host in H. excavatum, and the lowest in R. bursa (1.02 tick/host).

Conclusions

These findings reveal that the abundance of ticks varied among species and seasons.

Development of a protective inactivated vaccine against Crimean-Congo hemorrhagic fever infection

Crimean-Congo hemorrhagic fever (CCHF) is an emerging zoonotic infectious disease caused by Crimean-Congo hemorrhagic fever virus (CCHFV). The first clinical CCHF infection was described in 1944 in the Crimean Peninsula, exclusively in humans, with case-fatality rates exceeding 30%. The increasing number of cases, high mortality rate, and lack of effective therapy make CCHF a serious threat to public health and a potential bioterrorism agent. The present study evaluated the development, immunogenicity, and immune response durations for cell-culture-derived inactivated vaccine (CCVax) formulations in comparison with those of mouse-brain-derived vaccine (MBVax) formulations. In this study, the Kelkit06 CCHF virus strain was propagated in both suckling mice and Vero E6 cells, and purified with a sucrose gradient. Formalin-inactivated vaccine candidates were formulated at various doses [low dose (LD), 5 μg; medium dose (MD), 10 μg; high dose (HD), 20 μg)] and mixed with an alum adjuvant. BALB/c mice received the same doses of the vaccine formulations three times at 3-week intervals. The humoral endpoint IgG responses were evaluated and compared for the MBVax and CCVax treatments. The duration of the presence of IgG and neutralizing antibody (Ab) titers was evaluated and compared until up to 1 year after immunization. The humoral IgG responses indicated that the CCVax and MBVax candidates enhanced the IgG endpoint titers in a dose-dependent manner, which were induced more strongly in all the CCVax groups than in the MBVax mice. The fold changes in neutralizing Ab levels were also found to be higher in the CCVax groups: between 2- and 7.6-fold after the second week of the last immunization. The neutralization titers peaked 4 months after immunization in all the vaccine-receiving groups, but these were still comparable at the end of the first year. The CCVax formulations induced higher IgG and neutralizing Ab titers at all the measured time points. In this study, we showed that cell-culture-purified and formalin-inactivated vaccine candidates induced strong and robust immunity in vaccinated mice dose-dependently, more so than mouse-brain-derived vaccines.

Monthly infestation characteristics of ticks on cattle in Thrace, a Crimean Congo hemorrhagic fever-endemic area of Turkey

The first etiologically confirmed cases of Crimean-Congo hemorrhagic fever (CCHF) in humans were detected in Turkey in 2002. Since then, thousands of cases have been reported from different parts of the country. Hyalomma (Hy.) marginatum is considered the main vector tick of CCHFe in Turkey, and the primary infection route for humans is known to be the tick bite. This study was carried out between January 2013 and December 2014 in Thrace, Turkey, to determine monthly prevalence and intensity of tick infestation in cattle and, ultimately, to predict the related risk of human exposure to ticks and tick-borne diseases. During the study, 1,701 cattle in 24 villages were screened for ticks; 24,012 adult ticks, 1,887 nymphs, and 766 larvae were encountered on 1,228 of these cattle. On the 1,318 cattle that routinely grazed in the daytime, Hy. marginatum was the most predominant species, with an infestation prevalence of 73.6% and an average tick intensity of 16.1 on the infested cattle. In order of prevalence (%) in the grazing cattle, Hy. marginatum was followed by Rhipicephalus (R.) bursa (32.7%), R. turanicus (%29.5), Ixodes (I.) ricinus (15.1%), Haemaphysalis (Ha.) parva (10.4%), Ha. inermis (10%), Ha. punctata (6.5%), and Dermacentor (D.) marginatus (2.3%). The obtained data were discussed in terms of the infestation characteristics of the observed tick species, the drivers that may affect these characteristics, and the features of possible relationship between Hy. marginatum infestation in the cattle and CCHF cases among humans in the area.

Prevalence and phylogenetic analysis of Crimean-Congo hemorrhagic fever virus in ticks collected from Punjab province of Pakistan

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonotic disease of human that caused by CCHF virus. To study the epidemiological distribution of CCHFV, 2183 tick samples were collected from sheep, goats, cattle and buffalo of different livestock farms of ten districts of Punjab province of Pakistan. Detection of CCHFV was done using enzyme link immunosorbent assay (ELISA) after proper identification of tick samples. The partial S-segment of CCHFV from ELISA positive tick samples was amplified by PCR and sequenced to determine the genotype of CCHFV. Out of2183 collected tick samples, 1913 ticks belonged to 5 species of genus Hyalomma as H. antolicum (48%), H. marginatum (30.2%), H. rufipes (10.82%), H. impressum (5.43%) and H. dromedarii (5.27%). While 270 ticks belonged to 3 species of genus Rhipicephalus as R. microplus (44.8%), R. sanguineus (32.22%) and R. turanicus (24.8%). The overall antigenic prevalence of CCHFV was found to be 12.13% in collected tick samples and 21 tick pools were sequenced for partial S-segment of CCHFV. All of the 21 tick pools were clustered in genotype IV (Asia-1). The highest prevalence of CCHFV was found in district Chakwal (24.13%) followed by Mianwali (23.68%), Rawalpindi (23.07%), Attock (20.0%), Rajanpur (10.52%) and Lahore (8.33%). In positive tick pools, the highest prevalence of CCHFV antigen was found in H. antolicum (39.6%) followed by H. marginatum (30.18%), H. rufipes (13.2%), H. impressum (3.77%), H. dromedarii (1.88%), R. microplus (5.66%) and R. sanguineus (5.66%). The current study confirms the presence of CCHFV in the ticks population of Punjab. The CCHF virus present in Punjab belongs to Asia-1 genotype. It is important to control the tick infestation of the animals present in these areas. So that the transmission cycle of CCHF can be inhibited.

High prevalence and different genotypes of Crimean-Congo hemorrhagic fever virus genome in questing unfed adult Hyalomma marginatum in Thrace, Turkey

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease in the old continents, in many countries south of the 50 °North Parallel. The agent is known to be the most prevalent and major cause of severe and fatal human hemorrhagic diseases among the tick-borne viruses, and is the second most widespread of all medically critical arboviruses following dengue. Members of the Hyalomma genus are mainly involved in the natural transmission of the CCHF virus (CCHFV); of those, H. marginatum is known to be the primary vector of the disease in the Western Palaearctic. In general, epidemiological studies have been based on serological detections in the hosts and/or virus screening of ticks collected from the hosts. To the best of our knowledge, only a few studies have been carried out to screen the virus in unfed, questing field ticks. Nevertheless, detection of the virus in questing ticks is known to be a crucial parameter to determine the possible vector roles of the ticks and to understand the ecological dynamics of related diseases. In this study, 200 (75 males,125 females) questing H. marginatum adults collected from the field in nine villages in Thrace, located in the European part of Turkey, were screened individually for CCHFV using nested PCR. As a result, 103 (51.5 %) ticks were determined as positive with various strains of CCHFV. High positivity in questing vectors in a region where a significantly lower number of human cases have been encountered suggests that there should be some region-specific drivers that are effective in the natural dynamics of the disease. Detailed etiological and epidemiological studies are needed to reveal the possible reason for this unexpected discrepancy.

Investigation of Vector-Borne Viruses in Ticks, Mosquitos, and Ruminants in the Thrace District of Turkey

There is a considerable increase in vector-borne zoonotic diseases around the world, including Turkey, such as Crimean-Congo hemorrhagic fever (CCHF), tick borne encephalitis (TBE), Rift Valley fever (RVF), and West Nile fever (WNF), causing disease and death in humans and animals and significant economical losses. Hence, the aim of this study was to investigate the presence of CCHF virus (CCHFV) and TBE virus (TBEV) in ticks and RVF virus (RVFV) and WNF virus (WNV) in mosquitos, as well as in sheep and cattle, in the Thrace district of the Marmara region, which borders Bulgaria and Greece. Buffy-coat samples from 86 cattle and 81 sheep, as well as 563 ticks and 7390 mosquitos, were collected and examined by quantitative real-time RT-PCR for the presence of CCHFV, TBEV, RVFV, and WNV. All buffy-coat samples from cattle and sheep were negative for these viruses. Similarly, all tick samples were negative for CCHFV-RNA and TBEV-RNA. Among 245 pools representing 7390 mosquitos, only 1 pool sample was found to be positive for WNV-RNA and was confirmed by sequencing. Phylogenetic analysis revealed that it was WNV lineage-2. No RVFV-RNA was detected in the 245 mosquito pools. In conclusion, results of this study indicate that CCHFV, TBEV, and RVFV are not present in livestock and respective vectors in the Thrace district of Marmara region of Turkey, whereas WNV-RNA was found in mosquitos from this region.

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.

Can Bats Serve as Reservoirs for Arboviruses?

Bats are known to harbor and transmit many emerging and re-emerging viruses, many of which are extremely pathogenic in humans but do not cause overt pathology in their bat reservoir hosts: henipaviruses (Nipah and Hendra), filoviruses (Ebola and Marburg), and coronaviruses (SARS-CoV and MERS-CoV). Direct transmission cycles are often implicated in these outbreaks, with virus shed in bat feces, urine, and saliva. An additional mode of virus transmission between bats and humans requiring further exploration is the spread of disease via arthropod vectors. Despite the shared ecological niches that bats fill with many hematophagous arthropods (e.g. mosquitoes, ticks, biting midges, etc.) known to play a role in the transmission of medically important arboviruses, knowledge surrounding the potential for bats to act as reservoirs for arboviruses is limited. To this end, a comprehensive literature review was undertaken examining the current understanding and potential for bats to act as reservoirs for viruses transmitted by blood-feeding arthropods. Serosurveillance and viral isolation from either free-ranging or captive bats are described in relation to four arboviral groups (Bunyavirales, Flaviviridae, Reoviridae, Togaviridae). Further, ecological associations between bats and hematophagous viral vectors are characterized (e.g. bat bloodmeals in mosquitoes, ingestion of mosquitoes by bats, etc). Lastly, knowledge gaps related to hematophagous ectoparasites (bat bugs and bed bugs (Cimicidae) and bat flies (Nycteribiidae and Streblidae)), in addition to future directions for characterization of bat-vector-virus relationships are described.

Genotypic analysis of S segment of Crimean-Congo hemorrhagic fever virus in Turkey

The Crimean-Congo hemorrhagic fever (CCHF) virus (CCHFV) is a tick-borne virus, whose viral RNA consists of S, L, and M segments. The virus is migrating through the ticks with animals and migratory birds and the geographical distribution can be investigated based on genetic analysis. To better understand the connection between the seropositivity and the mortality rate, the key factor could be the temporal and spatial analysis of the different strains. In this study, serum samples (n = 26) were selected from CCHFV RNA-positive patients and subjected to sequence analysis of the gene regions encoding the S segments. According to the neighbor-joining analysis, the obtained partial sequences were linked to the European strain. The strains were closely related to Turkey-Kelkit06, Turkey 200310849 viruses, and viruses from Russia and Kosovo. The comparison with previously analyzed isolates from the GenBank showed 95%-99% sequence similarity. The isolates in phylogenetic branches were divided into two groups. AST, platelet, and APTT levels were found significantly higher in Group 2 compared to Group 1. Nucleotide differences can be prognostic factor in CCHF disease. Increasing CCHF cases not originating from local isolates were circulating strains imported from different neighboring countries of Turkey. The results show new evidence to the emerging threat of the CCHF disease.

Seasonal distribution and faunistic of ticks in the Alashtar county (Lorestan Province), Iran

Introduction

Ticks are non-permanent obligate parasites that have considerable medical-veterinary and zoonosis importance. In this regard a study designed to investigate the distribution and fauna of ticks in the Alashtar county in Iran from April and March 2014.

Methods

Ticks were collected from livestock farms and facilities from selected rural and geographically location in the Alashtar county. Based morphological characteristics and reference identification keys, ticks were identified.

Results

A total of 549 ticks including 411 hard and 138 soft ticks were found. Ten tick species including Haemaphysalis concinna (0.36%), Haemaphysalis sulcata (0.36%), Hyalomma anatolicum (0.18%), Hyalomma dromedarii (0.18%), Hyalomma marginatum (1.45 %), Hyalomma schulzei (0.36%), Rhipicephalus annulatus (0.18%), Rhipicephalus bursa (28.1%), Rhipicephalus sanguineus (43.63%) and Argas persicus (25.2%) were identified. Tick seasonal distribution were 47.26%, 22.63%, 14.96% and 15.15% in the spring, summer, autumn and winter, respectively. The tick distribution was more from plain areas (64.96%) than the mountainous areas (35.04%). The rates of the tick contamination were 97.3% and 2.7% in the traditional and industrial livestock's, respectively. The livestock contamination ranks to the hard ticks were cattle (39.51%), sheep (34.15%) and goats (26.34 %), respectively. Chi-square analysis showed a significant difference among the seasonal distribution of the ticks in the spring, summer and autumn or winter; between the tick distribution in the plain and mountainous areas; and between the traditional and industrial livestock's tick contamination (P < 0.05).

Conclusion

Present study proves to change the traditional livestock's to the industrial livestock's. These findings highlight the importance of ticks and shows need to their control and tick pest management.

The effect of excluding ungulates on the abundance of ixodid ticks on wild rabbit (Oryctolagus cuniculus)

Tick abundance depends heavily on host density, so reducing access to the host should reduce tick populations in a determined area. In this study we compared the Parasitic Index (PI = average number of ticks per rabbit) of two wild rabbit populations separated 16 years ago by a fence keeping ungulates from moving freely. Two areas were selected (closed and open) wherein 50 wild rabbits per area were sampled for ticks. The PI in the open area (PI = 989.62) was significantly higher than in the closed area (PI = 515.40). Hyalomma lusitanicum Koch was globally the most abundant species, followed by Rhipicephalus pusillus Gil Collado, Rhipicephalus bursa Canestrini and Fanzago, Haemaphysalis hispanica Gil Collado, Rhipicephalus sanguineus s.l. Latreille and Ixodes ventalloi Gil Collado. Differences between areas varied depending on the species. The number of H. hispanica, R. bursa and R. pusillus were significantly more abundant on rabbits in the closed area, whereas H. lusitanicum predominated in the open area. Ungulates in the open area may have played an important role as the main or alternative host for ticks and/or drawing some tick species away from rabbits. In the closed area other reasons such as inter-specific competition could have influenced the tick abundance. These results show a clear reduction in tick abundance for at least 16 years as well as influenced species distribution.

The role of ticks in the maintenance and transmission of Crimean-Congo hemorrhagic fever virus: A review of published field and laboratory studies

This manuscript is part of a series of reviews that aim to cover published research on Crimean-Congo hemorrhagic fever (CCHF) and its etiological agent, CCHF virus (CCHFV). The virus is maintained and transmitted in a vertical and horizontal transmission cycle involving a variety of wild and domestic vertebrate species that act as amplification hosts, without showing signs of illness. These vertebrates have traditionally been considered reservoirs of CCHFV, but in fact they develop only a transient viremia, while the virus can persist in ticks for their entire lifespan, and can also be transmitted vertically to the next generation. As a result, ticks are now considered to be both the vector and the reservoir for the virus. CCHFV has been detected in a wide range of tick species, but only a few have been proven to be vectors and reservoirs, mainly because most published studies have been performed under a broad variety of conditions, precluding definitive characterization. This article reviews the published literature, summarizes current knowledge of the role of ticks in CCHFV maintenance and transmission and provides guidance for how to fill the knowledge gaps. Special focus is given to existing data on tick species in which vertical passage has been demonstrated under natural or experimental conditions. At the same time, we identify earlier reports that used unreliable methods and perceptions to ascribe a vector role to some species of ticks, and have contributed to confusion regarding viral transmission. We also examine epidemiological pathways of CCHFV circulation and discuss priority areas for future research.

Prevalence of tick-borne haemoparasites in small ruminants in Turkey and diagnostic sensitivity of single-PCR and RLB

Background

Tick-borne haemoparasitic diseases (TBHDs), caused by Theileria, Babesia, Anaplasma and Ehrlichia, are common in regions of the world where the distributions of host, pathogen and vector overlap. Many of these diseases threaten livestock production and some also represent a concern to human public health. The primary aim of this study was to determine the prevalence of the above-mentioned pathogens in a large number of blood samples (n = 1979) collected from sheep (n = 1727) and goats (n = 252) in Turkey. A secondary aim was to assess the diagnostic sensitivity of a number of species-specific polymerase chain reaction (PCR) tests and the reverse line blotting (RLB) assay. DNA samples were screened using species-specific PCR for the presence of Theileria ovis, Theileria sp. MK, T. lestoquardi, T. uilenbergi, T. luwenshuni, Babesia ovis, Anaplasma ovis and A. phagocytophilum while RLB was undertaken to test for the presence of all known Theileria, Babesia, Anaplasma and Ehrlichia species. The diagnostic sensitivity of these two approaches was then compared in terms of their ability to detect single species and mixed infections.

Results

Overall, 84 and 74.43% of the small ruminants sampled were identified as hosting one or more pathogen(s) by species-specific PCR and RLB respectively. The presence of Theileria sp. OT1, T. luwenshuni and T. uilenbergi in Turkey was revealed for the first time while the presence of Babesia motasi, B. crassa and T. separata in Turkish small ruminants was confirmed using molecular methods. A high prevalence of mixed infection was evident, with PCR and RLB approaches indicating that 52.24 and 35.42% of animals were co-infected with multiple species, respectively. More than 80% of the mixed infections contained T. ovis and/or A. ovis. The RLB approach was found to be capable of detecting mixed infections with species such as Theileria sp. OT1, Theileria sp. OT3, T. separata, B. crassa and Babesia spp.

Conclusion

The results indicated that pathogens causing TBHDs are highly prevalent in sheep and goats in Turkey. The diagnostic sensitivity of species-specific single PCR was generally higher than that of RLB. However, the latter approach was still capable of identifying a high proportion of individuals containing mixed-species infections. The use of species-specific single PCR is recommended to accurately estimate pathogen prevalence and to identify co-infected hosts.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2151-3) contains supplementary material, which is available to authorized users.

Molecular epidemiology of Crimean-Congo haemorrhagic fever virus in India

Crimean-Congo haemorrhagic fever (CCHF) is an emerging zoonotic disease in India which is prevalent in neighbouring countries. CCHF virus (CCHFV) is a widespread tick-borne virus which is endemic in Africa, Asia, Eastern Europe and the Middle East. In the present study, samples of clinically suspected human cases from different areas of northern-western India were tested for the presence of CCHFV by RT–PCR through amplification of nucleocapsid (N) gene of CCHFV. Positive samples were sequenced to reveal the prevailing CCHFV genotype(s) and phylogenetic relatedness. A phylogenetic tree revealed the emergence of diverse strains in the study region showing maximum identity with the Pakistan, Afghanistan and Iran strains, which was different from earlier reported Indian strains. Our findings reveal for the first time the emergence of the Asia 1 group in India; while earlier reported CCHFV strains belong to the Asia 2 group.

Genetic Diversity of Crimean Congo Hemorrhagic Fever Virus Strains from Iran

BACKGROUND

Crimean Congo hemorrhagic fever virus (CCHFV) is a member of the Bunyaviridae family and Nairovirus genus. It has a negative-sense, single stranded RNA genome approximately 19.2 kb, containing the Small, Medium, and Large segments. CCHFVs are relatively divergent in their genome sequence and grouped in seven distinct clades based on S-segment sequence analysis and six clades based on M-segment sequences. Our aim was to obtain new insights into the molecular epidemiology of CCHFV in Iran.

METHODS

We analyzed partial and complete nucleotide sequences of the S and M segments derived from 50 Iranian patients. The extracted RNA was amplified using one-step RT-PCR and then sequenced. The sequences were analyzed using Mega5 software.

RESULTS

Phylogenetic analysis of partial S segment sequences demonstrated that clade IV-(Asia 1), clade IV-(Asia 2) and clade V-(Europe) accounted for 80 %, 4 % and 14 % of the circulating genomic variants of CCHFV in Iran respectively. However, one of the Iranian strains (Iran-Kerman/22) was associated with none of other sequences and formed a new clade (VII). The phylogenetic analysis of complete S-segment nucleotide sequences from selected Iranian CCHFV strains complemented with representative strains from GenBank revealed similar topology as partial sequences with eight major clusters. A partial M segment phylogeny positioned the Iranian strains in either association with clade III (Asia-Africa) or clade V (Europe).

CONCLUSION

The phylogenetic analysis revealed subtle links between distant geographic locations, which we propose might originate either from international livestock trade or from long-distance carriage of CCHFV by infected ticks via bird migration.

Crimean-Congo hemorrhagic fever in Turkey: Current status and future challenges

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease of humans that affects a wide geographic area of Africa and Eurasia, including Turkey, Iran, Pakistan, Afghanistan and Russia. Since the first detection of CCHF cases in Turkey in 2002, more than 9700 patients have been reported, with an overall mortality rate just under 5%. This article assesses the present epidemiological situation of CCHF in Turkey, with an updated literature review, describes national practices and summarizes lessons learned in preparation for future outbreaks.

Ticks (Acari: Ixodida) parasitizing humans in Corum and Yozgat provinces, Turkey

In order to identify ticks infesting humans in Corum and Yozgat provinces in Turkey, a total of 2110 ticks representing 14 species were collected on humans, between June and September 2009. Of those, 1551 (687♂, 450♀, 407 nymphs, 7 larvae) were collected from Corum and 559 (330♂, 180♀, 49 nymphs) were collected from Yozgat. The majority of ticks (n = 1121, 53.1 %) was Hyalomma marginatum. Other common ticks infesting humans were Dermacentor marginatus (n = 209, 9.9 %) and Rhipicephalus turanicus sensu lato (n = 145, 6.9 %) in the study area. In addition, a total of 386 immature Hyalomma were found on humans in Corum (335 nymphs, 7 larvae) and Yozgat (44 nymphs). Ixodes laguri and Haemaphysalis erinacei taurica were recorded for the first time in Corum. To the best of our knowledge, this study is the first detailed investigation on ticks infesting humans in Corum and Yozgat, except individual or incidental records. The present study provides useful information for those concerned with ticks and tick-borne diseases in Turkey.

The geographic distribution of cases of Crimean-Congo hemorrhagic fever: Kastamonu, Turkey

The purpose of this study was to analyze the epidemiological characteristics of cases diagnosed with Crimean-Congo Hemorrhagic Fever (CCHF) with the help of Geographic Information Systems (GIS) and to establish an epidemiological risk map. Data for 434 cases diagnosed with CCHF between 01.01.2004 and 31.12.2013 were subjected to statistical analysis SPSS 13.0 software. A digital map of Kastamonu was transferred onto ArcGIS 10.0 software in order to establish a risk map for CCHF. The highest cumulative incidence of CCHF is 41.29/10,000, and in people living at altitudes of 1001-1200 meters. ROC analysis of altitudes above sea level of residences with CCHF cases revealed an area under the curve of 74.5% (95% CI: 0.72-0.76, p<0.05). At a cut-off point of 836.5 meters, sensitivity was 0.74 and specificity 0.76. Cumulative incidence of CCHF was significantly positively correlated with number of animals per head (r=0.76) and area of agricultural land per head (r=0.59) (p<0.05). No significant correlation was determined between cumulative incidence and forested area percentages. This study reveals that both men and women living at more than 836.5 meters above sea level and working in agriculture and animal husbandry are at risk of CCHF between May and July. Detailed examination of the ecology of vector ticks is now needed in order to fully determine the epidemiology of the disease.

First phylogenetic analysis of a Crimean-Congo hemorrhagic fever virus genome in naturally infected Rhipicephalus appendiculatus ticks (Acari: Ixodidae)

Crimean-Congo haemorrhagic fever (CCHF) is a potentially fatal systemic viral disease in many parts of the world, including Iran. The nationwide incidence of human CCHF in endemic areas was 870 confirmed cases with 126 deaths (case fatality rate, CFR = 17.6 %) in the decade leading to 2012. The detection of the CCHF virus (CCHFV) genome in tick vectors is of fundamental importance for identifying these ticks as potential reservoirs of CCHFV infection. From May to October 2013, following detection of four new clinical cases resulting in two deaths in the city of Mashhad (northeast Iran), hard ticks were recovered from infested livestock in 40 villages in Khorasan-Razavi province and examined by the microscopic method for species identification. About a quarter of the ticks were then subjected to reverse-transcription polymerase chain reaction (RT-PCR) to detect the CCHFV genome. The PCR products were then sequenced, and their phylogenetic lineages were determined. A total of 407 hard ticks were captured, representing seven different species in two distinct genera. Members of the genus Hyalomma were widely distributed in all but two of the villages studied, and this was also the most frequent (83.3 %) tick genus. Of 105 adult ticks subjected to RT-PCR, four (3.8 %) ticks were found positive for the CCHFV genome. One brown ear tick, Rhipicephalus appendiculatus, was found to be naturally infected for the first time anywhere in the world. Ticks of Hyalomma asiaticum, Hyalomma marginatum, and Rhipicephalus turanicus were also found to be naturally infected with CCHFV. CCHFV found in these four different tick species were clustered in the same lineage with the Matin and SR3 strains from Pakistan and some other strains from Iran, indicating that these tick species were naturally infected with genetically closely related CCHFV in the region. The presence of CCHFV infection in four different hard tick species was confirmed using RT-PCR in northeast Iran. Part of this infection was attributed to Rh. appendiculatus, which is thus a potential new natural vector of CCHFV in Iran. It is also confirmed by phylogenetic analysis that CCHFV in this region is genetically closely related, even in the different tick species.

Molecular identification of Theileria and Babesia in ticks collected from sheep and goats in the Black Sea region of Turkey

A molecular survey was undertaken in the Black Sea region of Turkey to determine the presence of Theileria and Babesia species of medical and veterinary importance. The ticks were removed from sheep and goats, pooled according to species and locations, and analyzed by PCR-based reverse line blot (RLB) and sequencing. A total of 2241 ixodid ticks belonging to 5 genus and 12 species were collected and divided into 310 pools. Infection rates were calculated as the maximum likelihood estimation (MLE) with 95% confidence intervals (CI). Of the 310 pools tested, 46 (14.83%) were found to be infected with Theileria or Babesia species, and the overall MLE of the infection rate was calculated as 2.27% (CI 1.67-2.99). The MLE of the infection rates were calculated as 0.691% (CI 0.171-1.78) in Haemaphysalis parva, 1.47% (CI 0.081-6.37) in Rhipicephalus sanguineus, 1.84% (CI 0.101-7.87) in Ixodes ricinus, 2.86% (CI 1.68-4.48) in Rhipicephalus turanicus, 5.57% (CI 0.941-16.3) in Hyalomma marginatum, and 6.2% (CI 4.02-9.02) in Rhipicephalus bursa. Pathogens identified in ticks included Theileria ovis, Babesia ovis, Babesia bigemina, and Babesia microti. Most tick pools were infected with a single pathogen. However, five pools displayed mixed infections with T. ovis and B. ovis. This study provides the first molecular evidence for the presence of B. microti in ticks in Turkey.

Molecular epidemiology of Crimean-Congo hemorrhagic fever virus in Kosovo

Crimean-Congo hemorrhagic fever virus (CCHFV) is a zoonotic agent that causes severe, life-threatening disease, with a case fatality rate of 10–50%. It is the most widespread tick-borne virus in the world, with cases reported in Africa, Asia and Eastern Europe. CCHFV is a genetically diverse virus. Its genetic diversity is often correlated to its geographical origin. Genetic variability of CCHFV was determined within few endemic areas, however limited data is available for Kosovo. Furthermore, there is little information about the spatiotemporal genetic changes of CCHFV in endemic areas. Kosovo is an important endemic area for CCHFV. Cases were reported each year and the case-fatality rate is significantly higher compared to nearby regions. In this study, we wanted to examine the genetic variability of CCHFV obtained directly from CCHF-confirmed patients, hospitalized in Kosovo from 1991 to 2013. We sequenced partial S segment CCHFV nucleotide sequences from 89 patients. Our results show that several viral variants are present in Kosovo and that the genetic diversity is high in relation to the studied area. We also show that variants are mostly uniformly distributed throughout Kosovo and that limited evolutionary changes have occurred in 22 years. Our results also suggest the presence of a new distinct lineage within the European CCHF phylogenetic clade. Our study provide the largest number of CCHFV nucleotide sequences from patients in 22 year span in one endemic area.

Crimean-Congo hemorrhagic fever (CCHF) is an acute, tick-borne disease with a case fatality rate of 10–30%. It is geographically the most widespread tick-borne disease in the world. In recent years there has been an increase of the disease incidence in several countries, mainly in the countries of the Balkan. The disease is also endemic in Kosovo. Since CCHF virus is very genetically diverse we aimed to determine the genetic variability of the virus in Kosovo in the span of 22 years. We obtained the largest number of patient derived nucleotide sequences and found great genetic variability which has been more or less stable during the 22 year period. Our results also suggest that significant changes in viral population occur in different years. We show that ecological factors such as temperature could play a role in the composition of the viral population.

Tick survey and detection of Crimean-Congo hemorrhagic fever virus in tick species from a non-endemic area, South Marmara region, Turkey

Crimean-Congo hemorrhagic fever (CCHF) is an increasing health concern in Turkey since 2002. There were also some recent human cases from the South Marmara region of Turkey; thus, a tick survey was performed, and possible vector tick species for the CCHF virus were determined in the region. A total of 740 adult ticks were collected from infested livestock from five locations: Çanakkale-Biga, Bursa-Orhaneli, Bursa-Keles, Balıkesir and Bilecik. Total of 11 tick species from the genera Hyalomma, Rhipicephalus, Dermacentor, Ixodes and Haemaphysalis were identified. Rhipicephalus ticks were dominant in the region; the most frequently observed tick species was R. turanicus, (53.1 %), and only 15.4 % of the identified ticks were H. marginatum. The occurrence of H. rufipes infestation in the region fort he first time. A total of 73 pools of adult ticks were tested with both an antigen-detecting ELISA and RT real-time PCR (RT rt PCR). The presence of the CCHF virus was demonstrated in 9 (12.3 %) of the tested tick pools. Although seven of the tick pools were positive for the CCHF virus with both of the methods, one pool was positive only with RT rt PCR and the other pool was only positive with the ELISA. Positive results were obtained from ticks collected from cattle, sheep and goats from two locations, Bursa-Orhaneli and Bilecik. The CCHF virus was detected in R. turanicus (n = 3), R. bursa (n = 2), H. marginatum (n = 2) and D. marginatus (n = 2) ticks. The results of this study confirm the presence of the CCHF virus and present preliminary data on the vector tick species in the southern Marmara region of Turkey.

Genetic analysis and epidemiology of Crimean Congo Hemorrhagic fever viruses in Baluchistan province of Pakistan

Background

Pakistan is considered as an endemic country for Crimean-Congo Hemorrhagic fever with numerous outbreaks and sporadic cases reported during the past two decades. Majority of cases are reported from Baluchistan province with subsequent transmissions to non-endemic regions mainly through infected animals directly or via infested ticks. We hereby describe the molecular investigations of CCHF cases reported during 2008 in Quetta city of Baluchistan province.

Methods

Serum Samples from 44 patients, with clinical signs of hemorrhagic fever attending a tertiary care hospital in Quetta city, were collected and tested for CCHF virus antigen and genomic RNA, using capture IgM EIA kit and standard RT-PCR assay, respectively. The partial S-gene fragments were directly sequenced to get information related to the prevailing CCHFV genotypes and their molecular epidemiology in Pakistan.

Results

Out of the total forty four, sixteen (36%) samples were found positive for CCHF IgM. Similarly, viral RNA was detected in six (16%) samples. Phylogenetic analysis revealed that all study viruses belong to genotype Asia-1 with closest similarity (99-100%) to the previously reported strains from Pakistan, Afghanistan and Iran.

Conclusion

We conclude that CCHF virus remains endemic within Baluchistan and its neighboring regions of Afghanistan warranting a need of incessant surveillance activities.

Pseudo-plaque reduction neutralization test (PPRNT) for the measurement of neutralizing antibodies to Crimean-Congo hemorrhagic fever virus

Background

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which 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. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV.

Methods

Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies.

Results

Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed.

Conclusion

The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the measurement of CCHF neutralizing antibodies. This novel assay could serve as useful tools for CCHF research in epidemiology, vaccine development and other studies of immunity. It also provides an alternative to PRNT when viruses with no or poor CPE in cell culture.

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.

Seroprevalence of Crimean Congo hemorrhagic fever virus in Ijara District, Kenya

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease mainly affecting pastoralists who come in contact with animals infested with Hyalomma ticks, which are the key vectors of CCHF virus (CCHFV). CCHFV has been detected among these ticks in parts of North Eastern Kenya. This study aimed to identify acute cases of CCHF, and to determine the extent of previous exposure to CCHFV in an outpatient population attending Sangailu and Ijara health centers, Ijara District, North Eastern Kenya, presenting with acute febrile illnesses. A total of 517 human serum samples were collected from these patients. The samples were screened for the presence of IgM and IgG antibodies to CCHF using CCCHF-IgG and IgM ELISA test kits. A multivariable logistic regression model was used to investigate the risk factors associated with evidence of exposure to CCHFV. A single patient tested positive for anti-CCHF IgM, while 96 were positive for anti-CCHF IgG. The seroprevalence of CCHFV was 23% in Sangailu and 14% in Ijara. Most exposed persons were aged 40-49 years. The likelihood of exposure was highest among farmers (29%). Age, location, and contact with donkeys were significantly associated with exposure to CCHFV. Acute CCHFV infections could be occurring without being detected in this population. This study confirms human exposure to CCHF virus in Ijara District, Kenya, and identifies several significant risk factors associated with exposure to CCHFV.

Crimean-Congo hemorrhagic fever virus-tick survey in endemic areas in Bulgaria

The Balkan Peninsula and Bulgaria in particular, is a well-known endemic region for Crimean-Congo hemorrhagic fever (CCHF). This study describes the prevalence of Crimean-Congo hemorrhagic fever virus (CCHFV) among tick populations from areas, previously recognized with emerging cases of CCHF disease in humans. These include regions from the Southeastern (regions of Kardzhali and Haskovo) and Central (region of Stara Zagora) parts of the country. For the period 2006-2010 a total of 911 adult ticks, collected from livestock in endemic areas were studied for presence of CCHFV by an immunofluorescence-hemocytes assay (IFHA) and a reverse transcription-polymerase chain reaction (RT-PCR). The detection rate of CCHFV in the tick population was 2.09%. The prevalence of the virus was determined between 2.01% and 4.83% in the regions of Kardzhali and Haskovo, respectively (Southeastern Bulgaria). In the Central part of the country CCHFV infestation of the ticks was observed in 1.46% (region of Stara Zagora). The results confirmed the mosaic dispersion of CCHFV in the investigated regions. The principal infection vector in the surveyed areas was confirmed to be Hyalomma marginatum marginatum. Rhipicephalus sanguineus and Ixodes ricinus were also detected and may play a role in the transmission of CCHFV. Species distribution of CCHFV-positive ticks was as follows: H. m. marginatum-4.93%; R. sanguineus-2.33%; I. ricinus-1.02%. The combination of IFHA and RT-PCR that are used in this study are useful tools in the algorithm for monitoring endemic areas in Bulgaria.

Reverse transcription PCR-based detection of Crimean-Congo hemorrhagic fever virus isolated from ticks of domestic ruminants in Kurdistan province of Iran

Crimean-Congo hemorrhagic fever (CCHF) is a potentially fatal viral vector-borne zoonosis which has a mortality rate of up to 30% without treatment in humans. CCHF virus is transmitted to humans by ticks, predominantly from the Hyalomma genus. Following the report of two confirmed and one suspected death due to CCHF virus in Kurdistan province of Iran in 2007, this study was undertaken to determine the fauna of hard ticks on domestic ruminants (cattle, sheep, and goats) and their possible infection with CCHF virus using reverse transcription PCR technique. This is the first detection of CCHF virus in ticks from the Kurdistan province of Iran. Overall, 414 ixodid ticks were collected from two districts in this province. They represented four genera from which 10 separate species were identified. The Hyalomma genus was the most abundant tick genus (70%). It was the only genus shown to be infected with the CCHF virus using RT-PCR technique. The number of ticks positive for CCHF virus was 5 out of 90 (5.6%) adult ticks. The three remaining genera (Haemaphysalis, Rhipicephalus, and Dermacentor) were all negative following molecular survey. Four of the five virally-infected ticks were from cattle mainly in the Sanandaj district. We concluded that CCHF virus is present in the Hyalomma ticks on domestic ruminants (cattle) in Kurdistan province of Iran.

A survey of ixodid ticks feeding on cattle and prevalence of tick-borne pathogens in the Black Sea region of Turkey

The study reports the frequency of infestation and the prevalence of tick-borne pathogens in feeding adult ticks detached from cattle in two climatic zones of the Black Sea region of Turkey. A total of 2160 adult ticks were collected during 2007-2008. Of these, 1062 were randomly selected, divided into 224 pools, and tested for the presence of bovine Theileria, Babesia, and Anaplasma species. Eleven tick species were recognized on cattle in the study. Hyalomma marginatum was widely disrubuted in the semi-arid bioclimatic zone, but few specimens were collected in the humid bioclimatic zone. The most prevalent tick species in the humid climatic zone was Ixodes ricinus. Infection rates were calculated as the maximum likelihood estimation with 95% confidence intervals (CI). Overall, 4% (CI 2.87-5.44) of 224 tick pools were found to be positive for the pathoges by Reverse line blot. Maximum likelihood estimation of the infection rate varied among tick species, ranging from 2.68% (CI 0.16-12.68) in Haemaphysalis sulcata to 10.49% (CI 4.07-23.66) in Rhipicephalus bursa. The most prevalent tick-borne pathogen was Anaplasma phagocytophilum at 6.78% (CI 3.41-12.18) followed by A. centrale (6.56%, CI 0.42-31.47), Anaplasma/Ehrlichia spp. (3.61%, CI 1.99-6.06), Babesia spp. (3.33%, CI 1.65-6.03), and T. buffeli/orientalis (2.71%, CI 0.73-7.18). Sequencing results indicated that Babesia spp. shared 99% to 100% similarity with the unnamed Babesia sp. Kashi 1 and 2, Babesia sp. Kayseri 1 and Babesia sp.CS58. Anaplasma/Ehrlichia spp. were 98% and 100% identical to Ehrlichia canis and Ehrlichia sp. Omatjenne strain, respectively.

Distribution and seasonal activity of tick species on cattle in the West Aegean region of Turkey

The aim of the present study was to determine the identity, seasonal activity and distribution of tick species of cattle in the West Aegean region of Turkey between June 2006 and May 2008. Nine villages within three provinces, viz. Manisa, Izmir and Aydin, were included in the study and a total of 75 animal barns were visited monthly for a period of 24 months and 443 cattle were examined for the presence of ticks. It was determined that 23% of cattle were infested with ticks. A total of 19,679 adult ticks were collected. The most abundant tick species was Hyalomma marginatum (33.5%) and H. excavatum (16.9%) in the study area. Seasonal appearance of the adult ticks varied among species. Adult ticks of the Hyalomma genus were present throughout the year, although in smaller numbers during the winter. Species of Rhipicephalus were detected in all seasons except autumn. Rhipicephalus (Boophilus) annulatus was identified in July and August, Haemaphysalis parva was detected during the autumn. Ixodes ricinus and Dermacentor marginatus were identified during spring, autumn and winter. The study demonstrated the presence of I. ricinus, D. marginatus, Hyalomma rufipes and Hae. parva for the first time in the West Aegean region of Turkey.

A study on ovine tick-borne hemoprotozoan parasites (Theileria and Babesia) in the East Black Sea Region of Turkey

In this study, the frequency of Theileria and Babesia species was assessed via reverse line blotting and blood smear-based diagnostic methods in small ruminants. A total of 201 apparently healthy animals from 26 randomly selected herds located in 4 locations (Artvin, Giresun, Gumushane, and Tokat) of East Black Sea Region of Turkey were investigated for the blood protozoans. In a polymerase chain reaction (PCR), the hypervariable V4 region of the 18S ribosomal RNA gene was amplified with a set of general primers specific for all Theileria and Babesia species. The PCR products were hybridized against catchall and species-specific (Theileria spp., Theileria lestoquardi, Theileria ovis, Theileria sp. OT1, Theileria sp., OT3, Theileria sp., MK, Theileria luwenshuni, Theileria uilenbergi, Babesia spp., Babesia ovis, Babesia motasi, and Babesia crassa) probes. Theileria piroplasms were identified in nine (4.47%) samples by microscopic examination. Reverse line blotting (RLB) detected the infection in 19.90% of the samples. The infection rate of sheep (28.90%) was higher than goats (4.10%). T. ovis, Theileria sp., MK, and Theileria sp. OT3 were detected by RLB. The most prevalent Theileria species was T. ovis (18.90%) followed by Theileria sp. MK (0.99%). Theileria sp. OT3 was detected in one sample (0.43%). A single animal was infected as mix with T. ovis and Theileria sp. MK. The other Theileria (T. lestoquardi, Theileria sp. OT1, T. luwenshuni, and T. uilenbergi) and Babesia (B. ovis, B. motasi, and B. crassa) species were not detected. This study is the first molecular survey on ovine tick-borne protozoans in East Black Sea Region of Turkey.

Species distribution and detection of Crimean Congo Hemorrhagic Fever Virus (CCHFV) in field-collected ticks in Ankara Province, Central Anatolia, Turkey

Ticks may act as vectors for a number of infectious diseases including Crimean Congo Hemorrhagic Fever (CCHF). The causative agent is Crimean Congo Hemorrhagic Fever Virus (CCHFV), a member of Bunyaviridae, causing extensive ecchymosis, visceral bleeding and hepatic dysfunction with a high fatality rate in the affected individuals. CCHF was initially recognized in Turkey in 2002 and the current number of reported cases exceeds 4,400. This study was conducted to confirm the presence of tick species established as potential CCHFV vectors and investigate CCHFV activity in ticks at Ankara province, Turkey's second most-densely populated province, where CCHF cases were demonstrated. A total of 1,196 adult ticks, collected from various animals and vegetation in 12 sites located in 5 counties of Ankara during April-July 2010 were identified to species level. Twenty-two tick pools from county K2 were also evaluated for the presence of CCHFV RNA via a one-step real-time RT-PCR assay and reactive results were further confirmed by an in house nested RT-PCR assay. Nine tick species were identified: Rhipicephalus bursa (44.9%), R. sanguineus (18.9%), R. turanicus (18.1%), Haemaphysalis parva (8.3%), Hyalomma marginatum marginatum (5.4%), H. aegyptium (1.4%), H. anatolicum excavatum (1.3%), Hae. punctata (0.3%) and Dermacentor marginatus (0.2%). A total of five tick pools (22.7%) were reactive in real-time and nested RT-PCR assays. The pools included R. bursa, H. m. marginatum and Hae. parva ticks, collected from mammal hosts from two villages in one county. This is the first documentation of CCHFV activity in ticks from Ankara province, which indicates requirement for detailed surveillance to predict high risk zones in the region.

Crimean-Congo hemorrhagic fever virus in various ixodid tick species from a highly endemic area

Ticks are major vectors of numerous diseases affecting animals and humans. Presence of various tick-borne pathogens such as Crimean-Congo hemorrhagic fever virus (CCHFV) in various tick species was documented. CCHF is a severe tick-borne illness caused by the CCHFV which is a member of the Nairovirus genus (family: Bunyaviridae). Presence of CCHFV was shown in the most prevalent ixodid tick species such as Hyalomma marginatum and Rhiphicephalus bursa in Turkey. In the present study, prevalence and species diversity of ixodid ticks carrying CCHFV in Tokat province where CCHF is highly endemic were determined by using real-time reverse transcription-polymerase chain reaction (RRT-PCR). As a result, 15 out 745 ticks from various hosts (2%) were found to be CCHFV positive. The CCHFV positive ticks were Haemaphysalis concinna, Hyalomma anatolicum, Hyalomma detritum, Hyalomma marginatum, Hyalomma turanicum, Rhipicephalus bursa, and Rhiphicephalus turanicus indicating that multiple ixodid tick species may contribute to transmission of CCHFV to humans and animals in Turkey.

Epidemiology and mutational analysis of global strains of Crimean-Congo haemorrhagic fever virus

Crimean-Congo hemorrhagic fever (CCHF) is a severe illness with high fatality. Cases are reported in several countries in Africa, Europe, the Middle East, and Asia. Phylogenetic analyses based on the virus S (nucleocapsid), M (glycoprotein), and L (polymerase) genome segments sequences indicate distinct geographic lineages exist but their specific genetic characteristics require elucidation. In this work we collected all full length S segment sequences and generated a phylogenetic tree based on the alignment of these 62 samples. We then analyzed the alignment using entries from AAIndex, the Amino Acid Index database, to identify amino acid mutations that performed significant changes in charge, pka, hydropathy and side chain volume. Finally, we mapped these changes back to the tree and alignment to identify correlated mutations or sites that characterized a specific lineage. Based on this analysis we are able to propose a number of sites that appear to be important for virus function and which would be good candidates for experimental mutational analysis studies.