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Crimean‐Congo haemorrhagic fever virus (CCHFV) continues to cause new human cases in Iberia while its spatial distribution and ecological determinants remain unknown. The virus remains active in a silent tick‐animal cycle to which animals contribute maintaining the tick populations and the virus itself. Wild ungulates, in particular red deer, are essential hosts for Hyalomma ticks in Iberia, which are the principal competent vector of CCHFV. Red deer could be an excellent model to understand the ecological determinants of CCHFV as well as to predict infection risks for humans because it is large, gregarious, abundant and the principal host for Hyalomma lusitanicum. We designed a cross‐sectional study, analysed the presence of CCHFV antibodies in 1444 deer from 82 populations, and statistically modelled exposure risk with host and environmental predictors. The best‐fitted statistical model was projected for peninsular Spain to map infection risks. Fifty out of 82 deer populations were seropositive, with individual population prevalence as high as 88%. The highest prevalence of exposure to CCHFV occurred in the southwest of the Iberian Peninsula. Climate and ungulate abundance were the most influential predictors of the risk of exposure to the virus. The highest risk regions were those where H. lusitanicum is most abundant. Eight of the nine primary human cases occurred in or bordering these regions, demonstrating that the model predicts human infection risk accurately. A recent human case of CCHF occurred in northwestern Spain, a region that the model predicted as low risk, pointing out that it needs improvement to capture all determinants of the CCHFV infection risk. In this study, we have been able to identify the main ecological determinants of CCHFV, and we have also managed to create an accurate model to assess the risk of CCHFV infection. [ABSTRACT FROM AUTHOR]

Crimean-Congo hemorrhagic fever virus (CCHFV) has been detected in many African countries. Unfortunately, little is known about the current CCHFV situation in most of those countries including the Democratic Republic of the Congo (DRC). In over 50 years, three human CCHF cases have been detected in DRC but no seroepidemiological investigation was performed so far. To determine the prevalence of CCHFV-specific antibodies we tested 838 serum samples of cattle, goat and sheep from the southern province Katanga, DRC. The detected seroprevalence in ruminants was 1.6% ranging from 0.4% to 3.4% between the two sampling sites, Kamina and Lubumbashi. The low prevalence indicates only sporadic introduction of CCHFV into this part of the country. DRC is a very large country and the study was performed only at two locations in one province; therefore, the investigations can be only a starting point for further epidemiological activities. [ABSTRACT FROM AUTHOR]

Background: Crimean-Congo hemorrhagic fever virus (CCHFV) was detected for the first time in Mauritania in 1983 and several CCHFV outbreaks were reported in the following years. The last human case was diagnosed in 2015. However, no recent data exist about the prevalence of CCHFV in animals, although it is already described that prevalence studies in animals serve as good risk indicators. CCHFV can cause a severe hemorrhagic fever with a high case fatality rate in humans. Therefore, a precise risk assessment on the basis of updated data is very important. This article gives an overview about the current CCHFV prevalence in cattle in Mauritania. Methods and Findings: A seroprevalence study was carried out using 495 cattle sera from Mauritania, which were collected in the year 2013. The sera were analyzed by an inhouse CCHFV-IgG-ELISA. As second screening test, an adapted commercial CCHFV-IgG-ELISA was performed. Inconclusive sera were additionally tested by a modified commercial CCHFV-IgG-IFA. All assays showed high diagnostic sensitivity (>95%) and specificity (>98%). The overall prevalence of CCHFV-specific antibodies found in Mauritanian cattle was 67%, ranging from 56% to 90% in different provinces. Conclusion: This study shows a very high CCHFV-specific antibody prevalence in cattle in Mauritania. It is the highest seroprevalence detected in Mauritania so far. This strengthens the hypothesis that CCHFV is a serious and ongoing threat for public health in Mauritania. [ABSTRACT FROM AUTHOR]

In the last decade six Rickettsia species, including Rickettsia slovaca have been characterized in Germany. All of these species could be linked to distinct clinical syndromes in humans. However, due to lack of seroepidemiological data an estimation of the prevalence and the public health impact of rickettsial infections in Germany is difficult. The aim of the present study was to determine the seroprevalence of spotted fever group (SFG) rickettsiae in a population with an elevated exposure risk to ticks. For that purpose, 559 sera of forestry workers in the federal state of Brandenburg, Eastern Germany, were screened for SFG-rickettsiae reactive IgG antibodies. Positive sera were subsequently titrated by microimmunofluorescence assay against R. helvetica , R. raoultii , R. felis , “ R. monacensis “ and R. slovaca. The total average IgG seroprevalence rate against SFG rickettsiae of 27.5% was found to be represented by 9.7% R. helvetica , 5% R. raoultii , 2.7% R. felis , 0.5% “ R. monacensis “ and 0.5% R. slovaca. The remaining 9.1% positive test results were of non-differentiable origin. IgG seroprevalences ranged from 11% to 55% in the different forestry districts. Older and male participants had a significantly higher probability for seropositivity and higher anti-rickettsia antibody titer level. In addition, the number of recent as well as the recalled lifetime tick bites was significantly associated with seropositivity and higher titers against SFG rickettsiae. In conclusion, we found an unexpected high total seroprevalence against SFG rickettsiae in forestry workers and serological evidence confirming the occurrence of R. raoultii, R. felis, “ R. monacensis “ and R. helvetica in the federal State of Brandenburg. [ABSTRACT FROM AUTHOR]

Infections of humans with the tick-borne Crimean-Congo hemorrhagic fever virus (CCHFV) can cause a severe hemorrhagic fever with case fatality rates of up to 80%. Most humans are infected by tick bite, crushing infected ticks by hand or by unprotected contact with blood of viremic mammals. Next to the notified human CCHF cases, the real distribution and the situation in animals in Southeastern Europe are nearly unknown. Since domestic ruminants play a crucial role in the life cycle of the vector ticks and the transmission and amplification of the virus, the antibody prevalence in those animals is a good indicator for the presence of CCHFV in a region. Therefore, the prevalence of CCHFV-specific antibodies was investigated in domestic ruminants of different regions of Bulgaria and Turkey. Sera of 1165 ruminants were tested and a prevalence of up to 90% was identified. The overall prevalence for Bulgaria was 26% and for Turkey 57%. The results highlight the risk of human infections in those regions and the importance of the investigation of the prevalence in animals for identification of risk areas. This article provides a unique overview about published CCHFV antibody prevalence in animals in comparison to human incidences in different areas of Bulgaria and Turkey. Although it will help to complete the understanding of the CCHFV situation in these countries, it also demonstrates the lack of unpublished and published data even in these highly endemic areas. [ABSTRACT FROM AUTHOR]

Many viruses significantly impact human and animal health. Understanding the population dynamics of these viruses and their hosts can provide important insights for epidemiology and virus evolution. Puumala virus (PUUV) is a European hantavirus that may cause regional outbreaks of hemorrhagic fever with renal syndrome in humans. Here, we analyzed the spatiotemporal dynamics of PUUV circulating in local populations of its rodent reservoir host, the bank vole (Myodes glareolus) during eight years. Phylogenetic and population genetic analyses of all three genome segments of PUUV showed strong geographical structuring at a very local scale. There was a high temporal turnover of virus strains in the local bank vole populations, but several virus strains persisted through multiple years. Phylodynamic analyses showed no significant changes in the local effective population sizes of PUUV, although vole numbers and virus prevalence fluctuated widely. Microsatellite data demonstrated also a temporally persisting subdivision between local vole populations, but these groups did not correspond to the subdivision in the virus strains. We conclude that restricted transmission between vole populations and genetic drift play important roles in shaping the genetic structure and temporal dynamics of PUUV in its natural host which has several implications for zoonotic risks of the human population. [ABSTRACT FROM AUTHOR]

Summary: Hantaviruses are etiological agents of hemorrhagic fever with renal syndrome in many parts of Asia and Europe. There has been no documented case of hantavirus disease from India, although serological evidence exists. We investigated the prevalence of hantavirus in the Indian population and tried to identify potential risk groups for hantavirus infections. The presence of hantavirus-specific IgG antibodies was prospectively evaluated in 661 subjects belonging to different groups, i.e. patients with chronic renal disease, warehouse workers and tribal members engaged in rodent trapping. Healthy volunteer blood donors were included as a control group. Thirty-eight seropositive samples were found using a combination of a commercial ELISA followed by an indirect immunofluorescence assay. Western blot using recombinant Hantaan virus nucleocapsid antigen confirmed the presence of anti-hantavirus IgG in 28 (74%) of the 38 sera tested. This study confirms the presence of hantaviruses in India and warrants increasing awareness of the problems of emerging pathogens and the threats they may pose to the public health system. [Copyright &y& Elsevier]