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The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) patients may be difficult to establish because ABPA shares many characteristics with coexisting atopy or other lung infections in these patients. This study aimed to evaluate the sensitivity and specificity of various paraclinical parameters in the diagnosis of ABPA in patients with CF.

Sixty-two selected strains of Salmonella serotype Enteritidis of 33 phage types (PTs), and one strain classified as RDNG, were characterised by four different chromosomally based typing methods to elucidate genetic relationships among strains of different phage types. Based on IS200-hybridisation patterns, two major groups, containing strains of the most commonly encountered phage types, and six minor groups (seven with the RDNC strain included) were observed. IS200 pattern was a stable epidemiological marker in strains of all phage types except PT 6a and 14b. Ribotyping separated strains of the phage types into one major and five minor groups; the pattern of the RDNC strain was not seen with other strains. More than one ribotype was observed among strains of Enteritidis PTs 6, 7, 14b and 21. By pulsed-field gel electrophoresis, strains of 21 of the 33 phage types formed one large cluster when bands > 125 kb were used as the criterion for separation. Among strains belonging to PTs 1, 6, 7 and 14b, more than one pattern was observed by this method. By probing with five random cloned fragments of the Enteritidis chromosome, strains from 27 of 31 phage types examined showed the same hybridisation pattern. With the combined use of four genotypic methods, two groups of strains, representing eight and seven of 33 Enteritidis phage types, were formed; these two groups may be considered as the main evolutionary lines of Enteritidis. Strains of the remaining phage types, and the RDNc strain, belonged to separate groups.

Despite the fact that no firm evidence was obtained, epidemiological investigations of a recent Danish outbreak of fowl typhoid indicated that the infection might have been introduced by contaminated crates from a German slaughterhouse. Fourteen Danish and five German isolates of Salmonella enterica serovar Gallinarum biovar gallinarum obtained from recent outbreaks in Denmark and Germany were characterized by phenotypic and genomic methods. Phenotypic characters, plasmid profiling, plasmid restriction profiling and ribotyping strongly indicated that Danish and German isolates were of the same clone. Pulsed-field gel electrophoresis of genomic DNA digested with Xba I, however, separated Danish and German isolates. This observation was confirmed when Not I was used for digestion of DNA. This enzyme also separated German isolates into two groups. However, differences observed between pulsed-field gel electrophoresis profiles of Danish and German isolates did not exclude the possibility of epidemiological relatedness. The use of several molecular methods is consequently highly recommended when conducting epidemiological investigations of outbreaks at the level of individual isolates.

The ability to subtype bacteria by typing methods provides the bacteriologist with a powerful means to identify relationships between bacteria. This knowledge is used to identify routes of disease transmission among livestock and from livestock to humans. In the present paper, the principles of bacterial typing and the most commonly applied typing methods for use in veterinary public health are discussed in the context of their application in the investigation of salmonella epidemiology. Typing methods are now routinely used in most investigations on this subject and have provided insight into routes of transmission, reservoirs of infection and mechanisms of persistent infection. Under the EC order on zoonotic diseases, extended surveillance on the presence of zoonotic bacteria in livestock must be expected. To receive the maximum benefits of this surveillance, selected typing methods must be applied to all isolates of e.g. salmonella. At present, serotyping, and phage typing where applicable, are the most obvious choices for continuous surveillance of this organism. Random amplification of polymorphic DNA (PCR based typing) may have the potential for allocating strains into relevant groups quicker and without the requirement for additional manpower, and this method may be preferred in future.