Before this report, 7 autochthonous human cases of Crimean-Congo hemorrhagic fever had been reported in Spain, all occurring since 2016. We describe the retrospective identification of an eighth case ...dating back to 2013. This study highlights that the earliest cases of an emerging disease are often difficult to recognize.
In Europe, many flaviviruses are endemic (West Nile, Usutu, tick-borne encephalitis viruses) or occasionally imported (dengue, yellow fever viruses). Due to the temporal and geographical ...co-circulation of flaviviruses in Europe, flavivirus differentiation by diagnostic tests is crucial in the adaptation of surveillance and control efforts. Serological diagnosis of flavivirus infections is complicated by the antigenic similarities among the Flavivirus genus. Indeed, most flavivirus antibodies are directed against the highly immunogenic envelope protein, which contains both flavivirus cross-reactive and virus-specific epitopes. Serological assay results should thus be interpreted with care and confirmed by comparative neutralization tests using a panel of viruses known to circulate in Europe. However, antibody cross-reactivity could be advantageous in efforts to control emerging flaviviruses because it ensures partial cross-protection. In contrast, it might also facilitate subsequent diseases, through a phenomenon called antibody-dependent enhancement mainly described for dengue virus infections. Here, we review the serological methods commonly used in WNV diagnosis and surveillance in Europe. By examining past and current epidemiological situations in different European countries, we present the challenges involved in interpreting flavivirus serological tests and setting up appropriate surveillance programs; we also address the consequences of flavivirus circulation and vaccination for host immunity.
In September 2010, an unusually high number of wild birds (partridges and pheasants) died in Cádiz in southwestern Spain. Reverse transcription PCR and virus isolation detected flavivirus infections. ...Complete nucleotide sequence analysis identified Bagaza virus, a flavivirus with a known distribution that includes sub-Saharan Africa and India, as the causative agent.
Multimorbidity is the coexistence of more than two chronic diseases in the same individual; however, there is no consensus about the best definition. In addition, few studies have described the ...variability of multimorbidity patterns over time. The aim of this study was to identify multimorbidity patterns and their variability over a 6-year period in patients older than 65 years attended in primary health care.
A cohort study with yearly cross-sectional analysis of electronic health records from 50 primary health care centres in Barcelona. Selected patients had multimorbidity and were 65 years of age or older in 2009. Diagnoses (International Classification of Primary Care, second edition) were extracted using O'Halloran criteria for chronic diseases. Multimorbidity patterns were identified using two steps: 1) multiple correspondence analysis and 2) k-means clustering. Analysis was stratified by sex and age group (65-79 and ≥80 years) at the beginning of the study period.
Analysis of 2009 electronic health records from 190,108 patients with multimorbidity (59.8% women) found a mean age of 71.8 for the 65-79 age group and 84.16 years for those over 80 (Standard Deviation SD 4.35 and 3.46, respectively); the median number of chronic diseases was seven (Interquartil range IQR 5-10). We obtained 6 clusters of multimorbidity patterns (1 nonspecific and 5 specifics) in each group, being the specific ones: Musculoskeletal, Endocrine-metabolic, Digestive/Digestive-respiratory, Neurological, and Cardiovascular patterns. A minimum of 42.5% of the sample remained in the same pattern at the end of the study, reflecting the stability of these patterns.
This study identified six multimorbidity patterns per each group, one nonnspecific pattern and five of them with a specific pattern related to an organic system. The multimorbidity patterns obtained had similar characteristics throughout the study period. These data are useful to improve clinical management of each specific subgroup of patients showing a particular multimorbidity pattern.
In the alarming context of risk of Zika virus (ZIKV) transmission in the Euro-Mediterranean area, there is a need to examine whether capacities to detect, diagnose and notify ZIKV infections in the ...region are in place and whether ongoing capacity-building initiatives are filling existing gaps.The MediLabSecure network, created in 2014, comprises 55 laboratories of virology and medical entomology and 19 public health institutions in 19 countries in the Balkans, North-Africa, the Middle-East and the Black Sea regions. It aims to set up awareness, risk assessment, monitoring and control of emerging and re-emerging vector-borne viruses. We here examine the actions and strategies that MediLabSecure has been implementing and how they will contribute to the prevention and control of the ZIKV threat in the Euro-Mediterranean area.Capacity-building for arbovirus diagnostics is a major objective of the project and follows a methodological rather than disease-driven approach. This enables the implementation of laboratory trainings on techniques that are common to several arboviruses, including ZIKV, and putting into action appropriate diagnostic tools in the target region.Moreover, by its One Health approach and the interaction of its four sub-networks in human virology, animal virology, medical entomology and public health, MediLabSecure is fostering intersectoral collaboration, expertise and sharing of information. The resulting exchanges (methodological, communication and operational) across disciplines and across countries, dedicated research on intersectoral collaboration and increasing diagnostic capacities are providing new paths and tools to public health professionals to face emerging viral threats such as a ZIKV epidemic in the Euro-Mediterranean region.
The Dilution Effect Hypothesis (DEH) argues that greater biodiversity lowers the risk of disease and reduces the rates of pathogen transmission since more diverse communities harbour fewer competent ...hosts for any given pathogen, thereby reducing host exposure to the pathogen. DEH is expected to operate most intensely in vector-borne pathogens and when species-rich communities are not associated with increased host density. Overall, dilution will occur if greater species diversity leads to a lower contact rate between infected vectors and susceptible hosts, and between infected hosts and susceptible vectors. Field-based tests simultaneously analysing the prevalence of several multi-host pathogens in relation to host and vector diversity are required to validate DEH. We tested the relationship between the prevalence in house sparrows (
Passer domesticus
) of four vector-borne pathogens–three avian haemosporidians (including the avian malaria parasite
Plasmodium
and the malaria-like parasites
Haemoproteus
and
Leucocytozoon
) and West Nile virus (WNV)–and vertebrate diversity. Birds were sampled at 45 localities in SW Spain for which extensive data on vector (mosquitoes) and vertebrate communities exist. Vertebrate censuses were conducted to quantify avian and mammal density, species richness and evenness. Contrary to the predictions of DEH, WNV seroprevalence and haemosporidian prevalence were not negatively associated with either vertebrate species richness or evenness. Indeed, the opposite pattern was found, with positive relationships between avian species richness and WNV seroprevalence, and
Leucocytozoon
prevalence being detected. When vector (mosquito) richness and evenness were incorporated into the models, all the previous associations between WNV prevalence and the vertebrate community variables remained unchanged. No significant association was found for
Plasmodium
prevalence and vertebrate community variables in any of the models tested. Despite the studied system having several characteristics that should favour the dilution effect (i.e., vector-borne pathogens, an area where vector and host densities are unrelated, and where host richness is not associated with an increase in host density), none of the relationships between host species diversity and species richness, and pathogen prevalence supported DEH and, in fact, amplification was found for three of the four pathogens tested. Consequently, the range of pathogens and communities studied needs to be broadened if we are to understand the ecological factors that favour dilution and how often these conditions occur in nature.
Avian models of West Nile virus (WNV) disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental ...research that needs to be conducted in biosecurity level 3 (BSL3) facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas.
Bluetongue (BT) is a climate change-related emerging infectious disease in Europe. Outbreaks of serotypes 1, 2, 4, 6, 8, 9, 11, and 16 are challenging Central and Western Europe since 1998. Measures ...to control or eradicate bluetongue virus (BTV) from Europe have been implemented, including movement restrictions and vaccination of domestic BTV-susceptible ruminants. However, these measures are difficult to apply in wild free-ranging hosts of the virus, like red deer (
Cervus elaphus), which could play a role in the still unclear epidemiology of BT in Europe. We show for the first time that BTV RNA can be detected in European red deer blood for long periods, comparable to those of domestic ruminants, after experimental infection with BTV-1 and BTV-8. BTV RNA was detected in experimentally infected red deer blood up to the end of the study (98–112
dpi). BTV-specific antibodies were found in serum both by enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VNT) from 8 to 12
dpi to the end of the study, peaking at 17–28
dpi. Our results indicate that red deer can be infected with BTV and maintain BTV RNA for long periods, remaining essentially asymptomatic. Thus, unvaccinated red deer populations have the potential to be a BT reservoir in Europe, and could threaten the success of the European BTV control strategy. Therefore, wild and farmed red deer should be taken into account for BTV surveillance, and movement restrictions and vaccination schemes applied to domestic animals should be adapted to include farmed or translocated red deer.
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