Observatoire Régional du Pneumocoque en région Pays de la Loire : résistance de Streptococcus pneumoniae (Sp) aux antibiotiques en 2009

National audienc

Observatoire régional du pneumocoque en région Pays de la Loire : résistance de Streptococcus pneumoniae aux antibiotiques en 2007

But de l’étudeEntre le 1er janvier et le 31 décembre 2007, les 20 laboratoires participant à l’observatoire régional du pneumocoque (ORP) Pays de la Loire ont collecté 331 souches invasives de Streptococcus pneumoniae afin d’étudier leur sensibilité aux antibiotiques et la répartition des sérogroupes/sérotypes. Méthode Les concentrations minimales inhibitrices (CMI) de la pénicilline G, de l’amoxicilline et du céfotaxime ont été déterminées par le centre coordinateur, par la méthode de référence de diffusion en milieu gélosé. Les résultats ont été interprétés selon les recommandations du CA-SFM. Les sensibilités à d’autres antibiotiques ont été étudiées et les typages des souches réalisées par le centre coordinateur. Résultats Trois cent trente et une souches ont été isolées en 2007. Elles provenaient de 30 liquides céphalorachidiens, 239 hémocultures, 53 pus d’otites moyennes aiguës et neuf liquides pleuraux. Le pourcentage de pneumocoques de sensibilité diminuée à la pénicilline G (PSDP) était de 39 % et restait plus élevé chez l’enfant (51 %) que chez l’adulte (35 %). Les PSDP étaient souvent multirésistants, avec en particulier un pourcentage élevé de résistance à l’érythromycine (87,6 % contre 8,4 % pour les pneumocoques sensibles à la pénicilline). Enfin, le sérogroupe majoritairement rencontré était le sérogroupe 19 (29,6 % des isolats). Conclusion Une diminution des PSDP a été observée depuis 2001 et les souches de haut niveau de résistance aux β-lactamines restent rares. Le pourcentage de PSDP observés en ORP Pays de la Loire demeure dans la moyenne nationale

Observatoire Régional du Pneumocoque en région Pays de la Loire : résistance de Streptococcus pneumoniae (Sp) aux antibiotiques en 2007

Date du colloque&nbsp;: 12/2008</p

Landscape and Local Habitat Correlates of Lady Beetle Abundance and Species Richness in Urban Agriculture

Landscape surroundings and local habitat management affect patterns of insect biodiversity. Knowing which landscape and local factors are more important for insect species diversity informs landscape and local scale land management, yet can be challenging to disentangle. We sought to identify 1) which landscape factors surrounding, and 2) which local habitat factors within urban community gardens influence patterns in lady beetle (Coccinellidae) abundance and species richness. We assessed lady beetle abundance and taxonomic diversity, garden habitat characteristics, and the surrounding landscape composition in 19 gardens over two consecutive years. We found that the amount of natural area surrounding gardens at 3 km was the strongest correlate of abundance and species richness. Specifically, gardens surrounded by less natural area (gardens embedded in more urban landscapes) had higher lady beetle abundance and richness. In gardens embedded in landscapes with more amounts of natural land, local habitat features such as ornamental abundance and crop diversity may become more important for maintaining lady beetle abundance and richness. Our results suggest that within more urban landscapes, lady beetles may aggregate and accumulate in relatively resource-rich habitats like gardens. Thus, urban landscape quality and local habitat management may all interact to shape lady beetle communities within gardens

Landscape and Local Habitat Correlates of Lady Beetle Abundance and Species Richness in Urban Agriculture

Landscape surroundings and local habitat management affect patterns of insect biodiversity. Knowing which landscape and local factors are more important for insect species diversity informs landscape and local scale land management, yet can be challenging to disentangle. We sought to identify 1) which landscape factors surrounding, and 2) which local habitat factors within urban community gardens influence patterns in lady beetle (Coccinellidae) abundance and species richness. We assessed lady beetle abundance and taxonomic diversity, garden habitat characteristics, and the surrounding landscape composition in 19 gardens over two consecutive years. We found that the amount of natural area surrounding gardens at 3 km was the strongest correlate of abundance and species richness. Specifically, gardens surrounded by less natural area (gardens embedded in more urban landscapes) had higher lady beetle abundance and richness. In gardens embedded in landscapes with more amounts of natural land, local habitat features such as ornamental abundance and crop diversity may become more important for maintaining lady beetle abundance and richness. Our results suggest that within more urban landscapes, lady beetles may aggregate and accumulate in relatively resource-rich habitats like gardens. Thus, urban landscape quality and local habitat management may all interact to shape lady beetle communities within gardens

The presence of aggressive ants is associated with fewer insect visits to and altered microbe communities in coffee flowers

The process of dispersal can shape ecological communities, but its influence is thought to be small compared to the effects of environmental variation or direct species interactions, particularly for microbial communities. Ants can influence movement patterns of insects and the microbes they vector, potentially affecting microbial establishment on plants, including in agroecosystems. Here, we examine how the presence of aggressive ants, which can influence floral visitation by bees and other pollinators, shapes the community composition of bacteria and fungi on coffee flowers in farms that differ in shade management intensity. We hypothesized that the presence of aggressive ants should reduce the frequency and diversity of floral visitors. Finally, we predicted that the effects of ants should be stronger in the low-shade farm, which has a less diverse community of floral visitors. We sampled microbial communities from nectar and pistils of coffee flowers near and far from nests of the aggressive ant Azteca sericeasur across two farms that vary in shade management and diversity of floral visitors. Bacterial and fungal community composition was characterized using Illumina sequencing of the 16S and ITS regions of the rRNA gene. Consistent with our expectation, Azteca presence was associated with a decrease in the number and diversity of visitors, visit duration and number of flowers visited. Azteca presence influenced microbial communities, but effects differed between farms. Azteca nests were associated with higher bacterial diversity in both farms, but the difference between flowers on trees with and without Azteca was greater in the high-shade farm. Azteca nests were associated with higher fungal diversity in the high-shade farm, but not the low-shade farm. In addition, the presence of ants was strongly associated with species composition of fungi and bacteria in flowers, but differentiation between ant and no-ant communities was greater in the low-shade farm. Specific operational taxonomic units (OTUs) were differentially associated with the presence of ants. We conclude that indirect interactions that influence dispersal may have large effects on microbial community composition, particularly in ephemeral microbial communities

Agroecological pest management in the city: Experiences from California and Chiapas

Urban gardens are a prominent part of agricultural systems, providing food security and access within cities; however, we still lack sufficient knowledge and general principles about how to manage pests in urban agroecosystems in distinct regions. We surveyed natural enemies (ladybeetles and parasitoids) and conducted sentinel pest removal experiments to explore local management factors and landscape characteristics that influence the provisioning of pest control services in California, USA, and Chiapas, Mexico. We worked in 29 gardens across the two locations. In each location, we collected data on garden vegetation, floral availability, ground cover management, and the percentage of natural, urban, and agricultural land cover in the surrounding landscape. We sampled ladybeetles, Chalcidoidea, and Ichneumonoidea parasitoids with sticky traps, and monitored the removal of three different pest species. Ladybeetle abundance did not differ between locations; abundance decreased with garden size and with tree cover and increased with herbaceous richness, floral abundance, and barren land cover. Chalcicoidea and Ichneumonoidea parasitoids were more abundant in Chiapas. Chalcicoidea abundance decreased with herbaceous richness and with urban cover. Ichneumonoidea abundance increased with mulch and bare ground cover, garden size, garden age, and with agriculture land cover but decreased with tree richness and urban cover. Predators removed between 15-100% of sentinel prey within 24 h but prey removal was greater in California. Generally, prey removal increased with vegetation diversity, floral abundance, mulch cover, and urban land cover, but declined with vegetation cover and bare ground. Although some factors had consistent effects on natural enemies and pest control in the two locations, many did not; thus, we still need more comparative work to further develop our understanding of general principles governing conservation biological control in urban settings

Agroecological pest management in the city: Experiences from California and Chiapas

Urban gardens are a prominent part of agricultural systems, providing food security and access within cities; however, we still lack sufficient knowledge and general principles about how to manage pests in urban agroecosystems in distinct regions. We surveyed natural enemies (ladybeetles and parasitoids) and conducted sentinel pest removal experiments to explore local management factors and landscape characteristics that influence the provisioning of pest control services in California, USA, and Chiapas, Mexico. We worked in 29 gardens across the two locations. In each location, we collected data on garden vegetation, floral availability, ground cover management, and the percentage of natural, urban, and agricultural land cover in the surrounding landscape. We sampled ladybeetles, Chalcidoidea, and Ichneumonoidea parasitoids with sticky traps, and monitored the removal of three different pest species. Ladybeetle abundance did not differ between locations; abundance decreased with garden size and with tree cover and increased with herbaceous richness, floral abundance, and barren land cover. Chalcicoidea and Ichneumonoidea parasitoids were more abundant in Chiapas. Chalcicoidea abundance decreased with herbaceous richness and with urban cover. Ichneumonoidea abundance increased with mulch and bare ground cover, garden size, garden age, and with agriculture land cover but decreased with tree richness and urban cover. Predators removed between 15-100% of sentinel prey within 24 h but prey removal was greater in California. Generally, prey removal increased with vegetation diversity, floral abundance, mulch cover, and urban land cover, but declined with vegetation cover and bare ground. Although some factors had consistent effects on natural enemies and pest control in the two locations, many did not; thus, we still need more comparative work to further develop our understanding of general principles governing conservation biological control in urban settings

Local and landscape drivers of arthropod abundance, richness, and trophic composition in urban habitats

Urban green spaces, such as forest fragments, vacant lots, and community gardens, are increasingly highlighted as biodiversity refuges and are of growing interest to conservation. At the same time, the burgeoning urban garden movement partially seeks to ameliorate problems of food security. Arthropods link these two issues (conservation and food security) given their abundance, diversity, and role as providers of ecosystem services like pollination and pest control. Many previous studies of urban arthropods focused on a single taxon (e.g. order or family), and examined either local habitat drivers or effects of landscape characteristics. In contrast, we examined both local and landscape drivers of community patterns, and examined differences in abundance, richness, and trophic structure of arthropod communities in urban forest fragments, vacant lots, and community gardens. We sampled ground-foraging arthropods, collected data on 24 local habitat features (e.g., vegetation, ground cover, concrete), and examined land-cover types within 2 km of 12 study sites in Toledo, Ohio. We found that abundance and richness of urban arthropods differed by habitat type and that richness of ants and spiders, in particular, varied among lots, gardens, and forests. Several local and landscape factors correlated with changes in abundance, richness, and trophic composition of arthropods, and different factors were important for specific arthropod groups. Overwhelmingly, local factors were the predominant (80 % of interactions) driver of arthropods in this urban environment. These results indicate that park managers and gardeners alike may be able to manage forests and gardens to promote biodiversity of desired organisms and potentially improve ecosystem services within the urban landscape. © 2013 Springer Science+Business Media New York

Local and landscape drivers of arthropod abundance, richness, and trophic composition in urban habitats

Urban green spaces, such as forest fragments, vacant lots, and community gardens, are increasingly highlighted as biodiversity refuges and are of growing interest to conservation. At the same time, the burgeoning urban garden movement partially seeks to ameliorate problems of food security. Arthropods link these two issues (conservation and food security) given their abundance, diversity, and role as providers of ecosystem services like pollination and pest control. Many previous studies of urban arthropods focused on a single taxon (e.g. order or family), and examined either local habitat drivers or effects of landscape characteristics. In contrast, we examined both local and landscape drivers of community patterns, and examined differences in abundance, richness, and trophic structure of arthropod communities in urban forest fragments, vacant lots, and community gardens. We sampled ground-foraging arthropods, collected data on 24 local habitat features (e.g., vegetation, ground cover, concrete), and examined land-cover types within 2 km of 12 study sites in Toledo, Ohio. We found that abundance and richness of urban arthropods differed by habitat type and that richness of ants and spiders, in particular, varied among lots, gardens, and forests. Several local and landscape factors correlated with changes in abundance, richness, and trophic composition of arthropods, and different factors were important for specific arthropod groups. Overwhelmingly, local factors were the predominant (80 % of interactions) driver of arthropods in this urban environment. These results indicate that park managers and gardeners alike may be able to manage forests and gardens to promote biodiversity of desired organisms and potentially improve ecosystem services within the urban landscape. © 2013 Springer Science+Business Media New York