[Severe hemoptysis in the onco-hematology patient]

In France, even though it occurs only exceptionally in cases of hemopathy, severe hemoptysis in cancer is the leading cause of hemoptysis. Without adequate treatment, in-hospital mortality exceeds 60%, even reaching 100% at 6 months. The management of severe hemoptysis should be discussed with the oncologist. Aside from situations of threatening hemoptysis, in which bronchoscopy should be performed immediately, CT angiography is an essential means of localizing the bleeding and determining the causes and the vascular mechanisms involved. In more than 90% of cases, hemoptysis is linked to systemic bronchial or non-bronchial hypervascularization, whereas in fewer than 5%, it is associated with pulmonary arterial origin or, exceptionally, with damage to the alveolar-capillary barrier. The most severely ill patients must be treated in intensive care in centers equipped with interventional radiology, thoracic surgery and, ideally, with interventional bronchoscopy. Interventional radiology is the first-line symptomatic treatment. In over 80% of cases, bronchial arteriography with embolization allows immediate control. Emergency surgery should be avoided, as it is associated with significant mortality. Appropriate and adequate care reduces hospital mortality to 30%, enabling patients to benefit from the most recent, survival-prolonging treatments.

Mapping the risk of exposure to Crimean-Congo haemorrhagic fever virus in the Iberian Peninsula using Eurasian wild boar (Sus scrofa) as a model

Crimean-Congo haemorrhagic fever (CCHF) virus (CCHFV) is a tick-borne zoonotic pathogen that can cause a lethal haemorrhagic disease in humans. Although the virus appears to be endemically established in the Iberian Peninsula, CCHF is an emerging disease in Spain. Clinical signs of CCHFV infection are mainly manifested in humans, but the virus replicates in several animal species. Understanding the determinants of CCHFV exposure risk from animal models is essential to predicting high-risk exposure hotspots for public health action. With this objective in mind, we designed a cross-sectional study of Eurasian wild boar (Sus scrofa) in Spain and Portugal. The study analysed 5,291 sera collected between 2006 and 2022 from 90 wild boar populations with a specific double-antigen ELISA to estimate CCHFV serum prevalence and identify the main determinants of exposure probability. To do so, we statistically modelled exposure risk with host- and environment-related predictors and spatially projected it at a 10 × 10 km square resolution at the scale of the Iberian Peninsula to map foci of infection risk. Fifty-seven (63.3 %) of the 90 populations had at least one seropositive animal, with seroprevalence ranging from 0.0 to 88.2 %. Anti-CCHFV antibodies were found in 1,026 of 5,291 wild boar (19.4 %; 95 % confidence interval: 18.3-20.5 %), with highest exposure rates in southwestern Iberia. The most relevant predictors of virus exposure risk were wild boar abundance, local rainfall regime, shrub cover, winter air temperature and soil temperature variation. The spatial projection of the best-fit model identified high-risk foci as occurring in most of western and southwestern Iberia and identified recently confirmed risk foci in eastern Spain. The results of the study demonstrate that serological surveys of CCHFV vector hosts are a powerful, robust and highly informative tool for public health authorities to take action to prevent human cases of CCHF in enzootic and emergency settings.

Efficacy of heat-inactivated Mycobacterium bovis vaccine delivered to European badgers (Meles meles) through edible bait

Badgers (Meles meles) are a major tuberculosis (TB) reservoir in Europe, with the potential to transmit infection to cattle. Here we assessed whether a recently described oral tuberculosis vaccine based on heat-inactivated Mycobacterium bovis (HIMB), delivered as edible baits, can protect badgers from infection. Eight badgers were given individually five baits, each one consisting of a ball of peanut butter, natural peanut and oat flakes including a dose of the vaccine containing 5 × 107 colony-forming units. In parallel, a control group of seven badgers did not receive the vaccine. One month and a half later a second dose of the vaccine was offered to the vaccinated group. Ninety-four days after the second dose, all badgers were challenged with M. bovis (103 colony-forming units per animal) delivered endobronchially to the right middle lung lobe. Clinical, immunological, pathological and bacteriological variables were measured throughout the whole study to assess the efficacy of the vaccine. Two vaccinated animals showed high bacterial load of M. bovis and worsening of pathological lesions of TB. Conversely, the other six vaccinated animals showed slight improvement in bacterial load and pathology with respect to the control group. These results suggest that delivering the TB vaccine via food bait can partially protect wild badger populations, although vaccination can lead to either protection or tolerization, likely depending on the animal's immune status and general condition at the time of vaccination. Further optimization of the vaccination trial/strategy is needed to reduce the rate of tolerization, such as altering vaccine dose, number of doses, type of bait, use of adjuvants or route of administration.

Management of women with abnormal uterine bleeding: Clinical practice guidelines of the French National College of Gynaecologists and Obstetricians (CNGOF)

OBJECTIVE

To provide French guidelines for the management of women with abnormal uterine bleeding (AUB).

DESIGN

A consensus committee of 26 experts was formed. A formal conflict-of-interest policy was developed at the beginning of the process and enforced throughout. The entire guidelines process was conducted independently of any industry funding (i.e. pharmaceutical or medical device companies). The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized.

METHODS

The last guidelines from the Collège National des Gynécologues et Obstétriciens Français on the management of women with AUB were published in 2008. The literature seems now sufficient for an update. The committee studied questions within 7 fields (diagnosis; adolescents; idiopathic AUB; endometrial hyperplasia and polyps; type 0-2 fibroids; type 3 or higher fibroids; and adenomyosis). Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and evidence profiles were compiled. The GRADE® methodology was applied to the literature review and the formulation of recommendations.

RESULTS

The experts' synthesis work and the application of the GRADE method resulted in 36 recommendations. Among the formalized recommendations, 19 are strong and 17 weak. No response was found in the literature for 14 questions. We chose to abstain from recommendations rather than providing advice based solely on expert clinical experience.

CONCLUSIONS

The 36 recommendations make it possible to specify the diagnostic and therapeutic strategies for various clinical situations practitioners encounter, from the simplest to the most complex.

[Hereditary hemorrhagic telangiectasia]

Hereditary hemorrhagic telangiectasia, also known as Rendu-Osler - Weber disease, is a rare, autosomal dominant vascular disease, with prevalence of 1/5,000. The condition is characterized by muco-cutaneous telangiectasias, which are responsible for a hemorrhagic syndrome of variable severity, as well as arteriovenous malformations (AVMs) appearing in the lungs, the liver, and the nervous system. They can be the source of shunts, which may be associated with high morbidity (neurological ischemic stroke, brain abscess, high-output heart failure, biliary ischemia…). It is therefore crucial to establish a clinical diagnosis using the Curaçao criteria or molecular diagnosis based on genetic analysis of the ENG, ACVRL1, SMAD4 and GDF2 genes. In most cases, multidisciplinary management allows patients to have normal life expectancy. Advances in interventional radiology and better understanding of the pathophysiology of angiogenesis have resulted in improved therapeutic management. Anti-angiogenic treatments, such as bevacizumab (BVZ, an anti-VEGF antibody), have proven to be effective in cases involving bleeding complications and severe liver damage with cardiac repercussions. Other anti-angiogenic agents are currently being investigated, including tyrosine kinase inhibitors.

Beyond Tuberculosis: Diversity and implications of non-tuberculous mycobacteria at the wildlife-livestock interface

Non-tuberculous mycobacteria (NTM) circulate between the environment, animals and humans entailing a double concern: their ability to interfere with tuberculosis diagnosis and their potential to cause infections in their hosts. However, published records on NTM infections in animals are still scarce. The aims of the present study were to describe the diversity of NTM circulating among wild and domestic species from Spain, and to analyse their implications as potential pathogenic microorganisms or as sources of interferences in the diagnosis of bovine tuberculosis. Overall, 293 NTM isolates of 277 animals were obtained from tissue samples collected between 2012 and 2019, and analysed through a multigene approach for mycobacteria identification. Thirty-one species were identified, being M. avium subsp. avium (Maa) and M. avium subsp. hominissuis (Mah), but also M. bouchedurhonense, M. nonchromogenicum and M. lentiflavum, the most abundant ones. Maa and M. lentiflavum were isolated in several animals showing tuberculosis-like lesions. Maa, Mah and M. nonchromogenicum were recovered from many cattle that had reacted to the tuberculin skin test (TST). Other NTM were also associated to these phenomena. These four mycobacterial species were geographically associated between wild boar and other hosts. The findings of the present study suggest that a high diversity of NTM circulates among wildlife and livestock. Wild boar and M. avium seem to play a relevant role in this epidemiological scenario. This article is protected by copyright. All rights reserved.

[Management of women with abnormal uterine bleeding: Clinical practice guidelines of the French National College of Gynecologists and Obstetricians (CNGOF)]

OBJECTIVE

To provide French guidelines for the management of women with abnormal uterine bleeding (AUB).

DESIGN

A consensus committee of 26 experts was formed. A formal conflict-of-interest (COI) policy was developed at the beginning of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, or medical devices). The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized.

METHODS

The last guidelines from the Collège national des gynécologues et obstétriciens français (CNGOF) on the management of women with AUB was published in 2008. The literature seems now sufficient for an update. The committee studied questions within 7 fields (diagnosis; adolescent; idiopathic AUB; endometrial hyperplasia and polyps; fibroids type 0 to 2; fibroids type 3 and more; adenomyosis). Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® methodology.

RESULTS

The experts' synthesis work and the application of the GRADE method resulted in 36 recommendations. Among the formalized recommendations, 19 present a strong agreement and 17 a weak agreement. Fourteen questions did not find any response in the literature. We preferred to abstain from recommending instead of providing expert advice.

CONCLUSIONS

The 36 recommendations made it possible to specify the diagnostic and therapeutic strategies of various clinical situations managed by the practitioner, from the simplest to the most complex.

Molecular survey of Besnoitia spp. (Apicomplexa) in faeces from European wild mesocarnivores in Spain

Numerous studies have unsuccessfully tried to unravel the definitive host of the coccidian parasite Besnoitia besnoiti. Cattle infections by B. besnoiti cause a chronic and debilitating condition called bovine besnoitiosis that has emerged in Europe during the last two decades, mainly due to limitations in its control associated with the absence of vaccines and therapeutical tools. Although the exact transmission pathways of B. besnoiti is currently unknown, it is assumed that the parasite might have an indirect life cycle with a carnivore as definitive host. Current lack of studies in wildlife might underestimate the importance of free-living species in the epidemiology of B. besnoiti. Thus, the aim of the present study is to assess the presence of Besnoitia spp. in free-ranging mesocarnivores in Spain. DNA was searched by PCR on faeces collected from wild carnivores as a first approach to determine which species could be considered as potential definitive host candidates in further research. For this purpose, a total of 352 faecal samples from 12 free-living wild carnivore species belonging to the Canidae, Felidae, Herpestidae, Mustelidae, Procyonidae and Viverridae families were collected in seven Spanish regions. PCR testing showed that Besnoitia spp. DNA was present in four faecal samples from red foxes collected in western Spain, an area with the greatest density of extensively reared cattle and associated with high incidence of bovine besnoitiosis in the country. To date, this is the first report of a B. besnoiti-like sequence (99.57% homology) from carnivore faeces in a worldwide context. Red foxes might contribute to the epidemiology of B. besnoiti, although further studies, mostly based on bioassay, would be needed to elucidate the accuracy and extent of these interesting findings.

Cost-effectiveness of public health interventions against human influenza pandemics in France: a methodological contribution from the FLURESP European Commission project

BACKGROUND

The FLURESP project is a public health project funded by the European Commission with the objective to design a methodological approach in order to compare the cost-effectiveness of existing public health measures against human influenza pandemics in four target countries: France, Italy, Poland and Romania. This article presents the results relevant to the French health system using a data set specifically collected for this purpose.

METHODS

Eighteen public health interventions against human influenza pandemics were selected. Additionally, two public-health criteria were considered: 'achieving mortality reduction ≥40%' and 'achieving morbidity reduction ≥30%'. Costs and effectiveness data sources include existing reports, publications and expert opinions. Cost distributions were taken into account using a uniform distribution, according to the French health system.

RESULTS

Using reduction of mortality as an effectiveness criterion, the most cost-effective options was 'implementation of new equipment of Extracorporeal membrane oxygenation (ECMO) equipment'. Targeting vaccination to health professionals appeared more cost-effective than vaccination programs targeting at risk populations. Concerning antiviral distribution programs, curative programs appeared more cost-effective than preventive programs. Using reduction of morbidity as effectiveness criterion, the most cost-effective option was 'implementation of new equipment ECMO'. Vaccination programs targeting the general population appeared more cost-effective than both vaccination programs of health professionals or at-risk populations. Curative antiviral programs appeared more cost-effective than preventive distribution programs, whatever the pandemic scenario.

CONCLUSION

Intervention strategies against human influenza pandemics impose a substantial economic burden, suggesting a need to develop public-health cost-effectiveness assessments across countries.

Traditional plants from Asteraceae family as potential candidates for functional food industry

Traditional plants have been used in the treatment of disease and pain due to their beneficial properties such as antioxidant, antiinflammation, analgesic, and antibiotic activities. The Asteraceae family is one of the most common groups of plants used in folk medicine. The species Achillea millefolium, Arnica montana, Bellis perennis, Calendula officinalis, Chamaemelum nobile, Eupatorium cannabinum, Helichrysum stoechas, and Taraxacum officinale have been used in different remedies in Northwest Spain. Besides health benefits, some of them like C. nobile and H. stoechas are already employed in cooking and culinary uses, including cocktails, desserts, and savory dishes. This study aimed to review the current information on nutritive and beneficial properties and bioactive compounds of these plants, which are not mainly used as foods but are possible candidates for this purpose. The report highlights their current uses and suitability for the development of new functional food industrial applications. Phenolic compounds, essential oils, and sesquiterpene lactones are some of the most important compounds, being related to different bioactivities. Hence, they could be interesting for the development of new functional foods.

Percutaneous Transpedicular Fixation by PEEK Polymer Implants Combined with Cementoplasty for Vertebral Compression Fractures: A Pilot Study

PURPOSE

To evaluate the feasibility and safety of percutaneous transpedicular fixation by PEEK polymer implants and cementoplasty for vertebral compression fracture (VCF).

MATERIALS AND METHODS

From February 2019 to December 2019, 6 consecutive patients (3 men and 3 women; mean age 55 ± 8 years; range 40-64 years) who had percutaneous transpedicular fixation with cementoplasty for the treatment of VCF (5 tumor lesions, 1 traumatic) were included. The procedure duration, length of hospital stay, and complications were reported. Visual analog scale (VAS) and the Oswestry disability index (ODI) for pain and disability were assessed before and 2 months after the procedure.

RESULTS

The mean procedure duration was 74 ± 47 min (range 20-140 min). The median length of hospital stay was 3 days (range 2-63) after the procedure. Only minor adverse events were reported (4 asymptomatic cement leakages) but no severe complications. No cases of procedural site fracture during follow-up were noted (median 198 days; range 78-238 days). The mean VAS score decreased from 6.2 ± 1.8 mm (median 6 mm; range 4-9 mm) before the procedure to 1.7 ± 2.1 mm (median 1; range 0-5 mm) after the procedure. The ODI decreased from 36 ± 14% (range 18-54%) before the procedure to 23 ± 10% (range 11-30%) at 2-months follow-up.

CONCLUSIONS

Percutaneous transpedicular fixation of VCF by PEEK implants with cementoplasty appears feasible and safe.

Patients' productivity losses and informal care costs related to ischemic stroke: a French population-based study

BACKGROUND AND PURPOSE

Large societal costs of stroke should not be ignored. We aimed to estimate patients' productivity losses and informal care costs during the first year after ischemic stroke.

METHODS

A cross-sectional survey was performed within the STROKE69 regional population-based cohort study. At 1 year post-stroke, each patient and the corresponding main informal caregiver received questionnaires followed by a telephone interview if necessary. Time losses were valued using the human capital approach and proxy good method for patients with and without a professional activity, respectively.

RESULTS

Among the 222 patients with ischemic stroke (58% men; mean age 68 years; and 86% with a modified Rankin Scale (mRS) score of <3 at 3 months), 54%, 32%, and 25% received informal, formal, and both cares, respectively. Among the 108 main informal caregivers, 63% were women, 74% lived with the patient, and 57% were retired or unemployed. The mean cost of productivity losses was estimated at €7589 ± €12 305 per patient in the first post-stroke year with 5.4%, 71.2%, and 23.4% of these being attributed to presenteeism, absenteeism, and leisure time, respectively. Informal care was given at an average of 25 h/week. The annual mean estimated total cost of informal care was €10 635 per caregiver.

CONCLUSIONS

Informal care and productivity losses of patients with ischemic stroke during the first post-stroke year represent a significant economic burden for society comparable to direct costs. These costs should be included in economic evaluations with the adoption of a societal perspective to avoid underestimating the societal stroke economic burden.

Risk factors associated to a high Mycobacterium tuberculosis complex seroprevalence in wild boar (Sus scrofa) from a low bovine tuberculosis prevalence area

Animal tuberculosis is a worldwide zoonotic disease caused principally by Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex (MTC). In southern Iberian Peninsula, wild reservoirs such as the wild boar, among other factors, have prevented the eradication of bovine tuberculosis. However, most of the studies have been focused on south-central Spain, where the prevalence of tuberculosis is high among wild ungulates and cattle herds. In northern regions, where wild boar density and bovine tuberculosis prevalence are lower, fewer studies have been carried out and the role of this species is still under debate. The aim of this study was to describe the temporal and spatial distribution of antibodies against MTC in wild boar from the Basque Country, northern Spain. Sera from 1902 animals were collected between 2010 and 2016. The seroprevalence was determined with an in house enzyme-linked immunosorbent assay and the search of risk factors was assessed by Generalized Linear Models. Overall, 17% of wild boars (326/1902; 95%CI, [15.5%–18.9%]) showed antibodies against MTC. Risk factors associated with seropositivity were the year and location of sampling, the number of MTC positive cattle, the distance to positive farms and the percentage of shrub cover. Younger age classes were associated with increased antibody titres among seropositive individuals. The seroprevalence detected was higher than those previously reported in neighbouring regions. Hence, further studies are needed to better understand the role of wild boar in the epidemiology of tuberculosis in low tuberculosis prevalence areas and consequently, its relevance when developing control strategies.

Naturally Avian Influenza Virus-Infected Wild Birds Are More Likely to Test Positive for Mycobacterium spp. and Salmonella spp

Wild birds often harbor infectious microorganisms. Some of these infectious microorganisms may present a risk to domestic animals and humans through spillover events. Detections of certain microorganisms have been shown to increase host susceptibility to infections by other microorganisms, leading to coinfections and altered host-to-host transmission patterns. However, little is known about the frequency of coinfections and its impact on wild bird populations. In order to verify whether avian influenza virus (AIV) natural infection in wild waterbirds was related to the excretion of other microorganisms, 73 AIV-positive samples (feces and cloacal swabs) were coupled with 73 AIV-negative samples of the same sampling characteristics and tested by real-time PCR specific for the following microorganisms: West Nile virus, avian avulavirus 1, Salmonella spp., Yersinia enterocolitica, Yersinia pseudotuberculosis, Mycobacterium avium subspecies, Mycobacterium tuberculosis complex, and Mycobacterium spp. Concurrent detections were found in 47.9% (35/73) of the AIV-positive samples and in 23.3% (17/73) of the AIV-negative samples (P = 0.003). Mycobacterium spp. and Salmonella spp. were found to be significantly more prevalent among the AIV-positive samples than among the AIV-negative samples (42.9% vs. 22.8%; P = 0.024 and 15.2% vs. 0.0%; P = 0.0015, respectively). Prevalence of concurrent detections differed significantly among sampling years (P = 0.001), host families (P = 0.002), host species (P = 0.003), AIV subtypes (P = 0.003), and type of sample (P = 0.009). Multiple concurrent detections (more than one of the tested microorganisms excluding AIV) were found in 9.6% (7/73) of all the AIV-positive samples, accounting for 20% (7/35) of the concurrent detection cases. In contrast, in AIV-negative samples we never detected more than one of the selected microorganisms. These results show that AIV detection was associated with the detection of the monitored microorganisms. Further studies of a larger field sample set or under experimental conditions are necessary to infer causality in these trends.

Detection of Wood Mice (Apodemus sylvaticus) Carrying Non-Tuberculous Mycobacteria Able to Infect Cattle and Interfere with the Diagnosis of Bovine Tuberculosis

Mycobacterial infections caused by the Mycobacterium tuberculosis complex (MTC) and non-tuberculous mycobacteria (NTM) are of great medical and veterinary relevance. The aim of this research was to study whether small mammals play a role in the epidemiology of mycobacterioses. Four samplings of 100 traps were performed in each of three cattle farms with previous history of tuberculosis or NTM between 2017 and 2018. A total of 108 animals belonging to seven species were trapped, classified, and necropsied, and tissues were submitted to microbiological and molecular methods for mycobacteria identification. The wood mouse (Apodemus sylvaticus) was the most abundant species (87%). No MTC was detected but six different NTM were identified (M. intracellulare, M. avium subsp. paratuberculosis, M. gordonae, M. celatum, M. fortuitum, and a not determined Mycobacterium sp.), showing a prevalence of 6.5%. No significant association was found between mycobacteria prevalence and the analyzed factors. Although a role in the epidemiology of MTC could not be attributed to small mammals, A. sylvaticus carries NTM that could be pathogenic or interfere with the diagnosis of tuberculosis. According to our results, there is a risk of NTM transmission at the wildlife–livestock interface through potential indirect contacts between small mammals and cattle.

Protective Effect of Oral BCG and Inactivated Mycobacterium bovis Vaccines in European Badgers (Meles meles) Experimentally Infected With M. bovis

In Europe, badgers (Meles meles) are recognized as major tuberculosis (TB) reservoir hosts with the potential to transmit infection to associated cattle herds. Recent studies in Spain have demonstrated that vaccination with a heat-inactivated Mycobacterium bovis vaccine (HIMB) successfully protects captive wild boar and red deer against progressive disease. The aim of this study was to evaluate the efficacy of two oral vaccines against TB in a badger model: the live-attenuated M. bovis bacillus Calmette-Guérin BCG vaccine (Danish strain) and a HIMB vaccine. Twenty-four badgers were separated in three treatment groups: oral vaccinated with live BCG (10⁸ CFU, n = 5), oral vaccinated with HIMB (10⁷ CFU, n = 7), and unvaccinated controls (n = 12). All badgers were experimentally infected with M. bovis (10³ CFU) by the endobronchial route targeting the right middle lung lobe. Throughout the study, clinical, immunological, pathological, and bacteriological parameters of infection were measured. Both vaccines conferred protection against experimental TB in badger, as measured by a reduction of the severity and lesion volumes. Based on these data, HIMB vaccination appears to be a promising TB oral vaccine candidate for badgers in endemic countries.

Blastocystis sp. Subtype Diversity in Wild Carnivore Species from Spain

The occurrence and molecular diversity of the stramenopile eukaryote Blastocystis sp. was investigated by PCR and sequencing (Sanger and NGS) methods in 380 faecal specimens of free-living carnivores in Spain. Blastocystis sp. was confirmed in 1.6% (6/380) of the specimens analysed. Two samples from a common genet and a fox were successfully subtyped as ST7 by Sanger. Using NGS, ST14 was found in a fox and a European polecat, ST7 in a fox, and two additional foxes presented mixed infections of ST1/ST2/ST4 and ST1/ST2/ST7, respectively. Wild carnivore species could act as carriers of zoonotic Blastocystis subtypes.

Sedation and analgesia in interventional radiology: Where do we stand, where are we heading and why does it matter?

The aims of this review were to describe the rationale and the techniques of sedation in interventional radiology, and to compile the safety and efficacy results available so far in the literature. A systematic MEDLINE/PubMed literature search was performed. Preliminary results from several studies demonstrated the feasibility, the efficacy and the safety of using sedative techniques in interventional radiology. Beyond pharmacological sedation and clinical hypnosis, digital sedation could reduce the anxiety and pain associated with interventional radiology procedures.

Long-term avian influenza virus epidemiology in a small Spanish wetland ecosystem is driven by the breeding Anseriformes community

During 2007-2009 and 2012-2014, avian influenza virus (AIV) was studied in a wild avian community of a northern Spanish wetland using non-invasive sampling methods and host identification by COI barcoding. The aim of this longitudinal study was to evaluate AIV dynamics in a natural wetland ecosystem, taking into account both virological aspects and ecological traits of hosts. Global AIV prevalence decreased significantly during the second sampling period (0.3%) compared to the first (6.6%). Circulating subtype distributions were also different between periods, with a noteworthy H5 and H7 subtype richness during the first sampling period. Mallard Anas platyrhynchos was identified as the main AIV host, although not all positive samples could be ascribed to the host. We modelled AIV prevalence with regard to the avian host community composition and meteorological data from the wetland. Statistical analysis revealed seasonal differences in AIV detection, with higher prevalence during the breeding season compared to other phenological events. The model also shows that the lower AIV prevalence during the second study period was associated with a significant reduction of breeding Anseriformes in the wetland, revealing a long-term fluctuation of AIV prevalence driven by the breeding Anseriformes community. This longitudinal study on AIV epidemiology in a natural ecosystem reveals that although prevalence follows seasonal and annual patterns, long-term prevalence fluctuation is linked to the breeding community composition and size. These results are relevant to understanding the influence of host ecology on pathogen transmission for preventing and managing influenza emergence.