Characterization of Cronobacter recovered from dried milk and related products

Background  

Cronobacter is a recently proposed genus consisting of six genomospecies that encompass the organisms previously identified as Enterobacter sakazakii. Cronobacter are opportunistic pathogens and are known to cause serious infections in infants, particularly neonates. High case fatality rates have been associated with infections and acute sequelae can occur in survivors with severe ramifications on neurological development. Infant formula has been identified as one route of transmission for infection in infants. However, the primary reservoirs for subsequent contamination of foods with Cronobacter remain undefined due to the ubiquitous nature of these organisms. More recently, infections in adults have been reported, especially amongst the elderly and patients who are immunocompromised. To help prevent the transmission of infection, it is important to identify the main food sources for Cronobacter. The aim of this study was to identify and characterize Cronobacter isolated from dried-milk and related products available in an Egyptian food market.     

The distribution of Oligochaeta on an exposed rocky shore in southeast Ireland

The distribution of oligochaetes was studied on a wave-exposed, granite shore at Carnsore Point, County Wexford. Habitats sampled were crevices and shallow surface cracks in rock, Lichina pygmaea turf, a Mytilus edulis bed, barnacles, Laurencia pennatifida turf, Corallina officinalis turf and pools. Lichina, mussels, barnacles greater than 8 mm in height, Laurencia and Corallina were sampled quantitatively.Three species of Tubificidae and nine species of Enchytraeidae were recorded including two new species described from this locality and five which are undescribed. Oligochaetes were present in all the habitats sampled but were rare in pools and numbers were low on barnacle-covered rock except where barnacles were more than 8 mm in height. The number of species increased with decreasing tide level and was highest in lower shore crevices. Highest densities were recorded from Corallina turf and in barnacles > 8 mm. Lumbricillus semifuscus was the most widespread species, occurring in crevices and mats at all tide levels; other species had more restricted distributions. Grania species were confined to Corallina turf. Only three species of oligochaete were recorded from cracks where they were almost the only fauna present. Species diversity and density were influenced by physical structure of the habitat, particularly the amount of retained sediment.The oligochaetes are members of a rich cryptofauna in habitats which provide them with organic matter and moisture and protect them from environmental extremes and wave damage and from predators during immersion. Reasons for the scarcity of oligochaete records from exposed rocky shores and the high proportion of new species in this study are discussed.