Spatial Distribution of Cryptic Species Diversity in European Freshwater Amphipods (Gammarus fossarum) as Revealed by Pyrosequencing

In order to understand and protect ecosystems, local gene pools need to be evaluated with respect to their uniqueness. Cryptic species present a challenge in this context because their presence, if unrecognized, may lead to serious misjudgement of the distribution of evolutionarily distinct genetic entities. In this study, we describe the current geographical distribution of cryptic species of the ecologically important stream amphipod Gammarus fossarum (types A, B and C). We use a novel pyrosequencing assay for molecular species identification and survey 62 populations in Switzerland, plus several populations in Germany and eastern France. In addition, we compile data from previous publications (mainly Germany). A clear transition is observed from type A in the east (Danube and Po drainages) to types B and, more rarely, C in the west (Meuse, Rhone, and four smaller French river systems). Within the Rhine drainage, the cryptic species meet in a contact zone which spans the entire G. fossarum distribution range from north to south. This large-scale geographical sorting indicates that types A and B persisted in separate refugia during Pleistocene glaciations. Within the contact zone, the species rarely co-occur at the same site, suggesting that ecological processes may preclude long-term coexistence. The clear phylogeographical signal observed in this study implies that, in many parts of Europe, only one of the cryptic species is present

Infection control in dentistry during COVID – 19 pandemic: what has changed?

The novel coronavirus (COVID-19) pandemic has emerged disrupting many socio-economical and healthcare aspects across the world. This virus can be transmitted by symptomatic and asymptomatic individuals through saliva and contact. Due to its airborne transmission, aerosols created by natural activities and during dental treatment of infected individuals have become a potential vehicle of transmission and threat. The objective of this review was to assess the existing infection control measures taken in dental health-care settings and suggest modifications to reduce the transmission of novel coronavirus. This is a general review publication. Literature search was made at National Library of Medicine, Pubmed using key words such as “dentistry and COVID”, “dentistry and COVID and infection control”. Publications related to behaviour, education, ethics, treatment and childcare were excluded. Publications describing general aspects of infection control were reviewed. Keyword “Dentistry and COVID and Infection control” generated 70 publications which were reviewed. Infection control measures in dentistry are designed to minimise cross transmission mainly of blood borne pathogens. The unique nature of COVID-19 including highly infectious and transmissibility, and the ability to survive for a long time in the environment requires special attention and modification to the existing infection control measures which are highlighted here. In conclusion, a modified infection prevention and control (IPC) regime will protect the dental practitioner, assistant and staff, patients and the community. During the pandemic, drastic measures are necessary, however, during an endemic period measures can be remodified as necessary