63 Sg/10a

Salmonella remains a threat to both animal and public health. Its economic significance remains high and changes in public perception mean that some measures for control may be necessary even in the absence of financial loss. Diagnosis is an important part of control. A great deal of new information has become available over the last few years as a result of research into various aspects of both diagnosis and control. This article seeks to summarise the progress in both these areas in the context of other recent reviews. New solid culture media, particularly Rambach agar, have become available which are selective for Salmonella. It is more reliable than either XLD or brilliant green agar but some Citrobacter species cause confusion. Enrichment-serological methods can shorten presumptive identification times. ELISAs for detection of Salmonella organisms are now available commercially but are limited by their cost and relatively low sensitivity. Their specificity is directly related to the type and quality of the detecting antibodies. Polymerase chain reaction technology has been assessed experimentally. Although it is not yet suitable for extensive use, its specificity and sensitivity suggests that it will have many advantages over other systems for rapid detection of Salmonella organisms. ELISAs are also being increasingly used for serological detection of invasive Salmonella infections in poultry flocks. They are used as an integral part of the control measures against Salmonella enteritidis and S. typhimurium in some countries. They could now also be used routinely for S. gallinarum and S. pullorum.