In order to estimate the risks of human granulocytic ehrlichiosis (HGE) in an endemic area for Lyme disease in the North of Spain (La Rioja), we collected and investigated by PCR specific to the E. phagocytophila group DNA, a total of 6870 Ixodes ricinus ticks. We also used an indirect immunofluorescence (IFI) test to study the presence of antibodies to the HGE agent in 147 human serum samples including patients with Lyme disease (LD), forestry workers, and persons with history of previous tick bite. Fifty serum samples from healthy people resident in urban areas and with no history of tick-bite disorder and without tick exposure were used as controls. Four of 76 adults and 49 of 203 nymphs pools carried E. phagocytophila DNA. This result, and the finding of 1·4% of sera reacting in the IFI test confirms that this tick-borne agent is present in La Rioja, and that humans show evidence of contact with it. HGE should be considered in the differential diagnosis of flu-like syndromes in the study area in the north of Spain.

PCR–IMS was used to detect Cryptosporidium spp. in environmental water samples in Northern Ireland which had previously tested negative by a conventional IFA staining method. Oocysts of C. parvum detected in river water and final treated sewage effluent collected from various sites along the river Lagan were identified as genotype 2 (animal origin) based on polymorphisms observed at the thrombospondin related adhesion protein gene locus. Similarly, genotype I (human origin) oocysts of C. parvum were detected in the marine filter feeder mussel, Mytilus edulis, collected from the shores of Belfast Lough. Detection of the human genotype of Cryptosporidium in mussels destined for human consumption identifies the organism's serious potential as a foodborne pathogen. This work highlights the possible value of monitoring filter feeder systems, in conjunction with specific molecular epidemiological tools, as an alternative monitoring system for the parasite within the aquatic environment.

The natural reservoir of Borna disease virus (BDV) is unknown. In this paper, we show that mallards (Anas platyrhyncos) and jackdaws (Corvus monedula) can be subclinically infected carriers of this virus. From faecal samples collected at a bird pond, we were able to amplify fragments of the BDV p24 and p40 genes. Following cloning and sequencing, a phylogenetic analysis revealed that these birds carry strains of BDV closely related to but distinct from the reference strains BDV V and He/80. To our knowledge, this is the first confirmed finding of BDV in wild birds.

Cattle are considered to be a reservoir host of Escherichia coli O157[ratio ]H7 and contaminated foods of bovine origin are important vehicles of human infection. In this study, the susceptibility of calves to experimental E. coli O157[ratio ]H7 infection following low oral exposures was determined. Two of 17 calves exposed to very low (<300 c.f.u.) doses, and 3 of 4 calves exposed to low (<10000 c.f.u.) doses, subsequently excreted the challenge strains in their faeces. All calves (n = 12) sharing isolation rooms with calves that excreted the challenge strain in their faeces similarly began faecal excretion of the same strains within 21 days or less. The identity between the challenge strains and the strains excreted in calf faeces was confirmed by restriction digestion electrophoretic patterns using pulsed field gel electrophoresis. Calves shed E. coli O157[ratio ]H7 in their faeces after very low dose exposures at concentrations ranging from <30 to >107 c.f.u./g, and for durations similar to the values previously reported for calves challenged by larger doses. The susceptibility of calves to infection following very low exposures or direct contact with infected calves has important implications for programmes for pre-harvest control of this agent.

An outbreak of trichinellosis that occurred in the United Kingdom is described. Members of four households consumed pork salami from northern Serbia, the Federal Republic of Yugoslavia. Eight cases of trichinellosis occurred. Clinical and laboratory features of the cases were typical with myalgia (7 cases), fever (6), headache (5), periorbital oedema (4), non-specific ST/T wave changes on electrocardiogram (3), Trichinella antibodies (6), eosinophilia (7) and raised serum creatine kinase (3). All recovered. Trichinella larvae were detected in the salami. During pre-travel counselling, travellers should be advised about possible risk from cured pork products which have been produced locally in Trichinella endemic areas.

We describe the prevalence of community-acquired M. pneumoniae pneumonia diagnosed by culture methods in a single institute in Japan from January 1979 to December 1999. Cultures were performed in 2971 pneumonia cases and yielded M. Pneumoniae in 508 cases. The epidemic peaks recurred regularly at 4-year intervals (1980, 84, 88 and 91–2). Although a large epidemic has not occurred since 1992, traces of epidemic periodicity have still persisted from 1992 to 1999 at 3-year intervals.

Aeromonas caviae has been implicated in diarrhoeal disease of livestock and humans. The potential role of houseflies in the epidemiology of this pathogen was investigated by examining the prevalence of A. caviae in houseflies collected from two South Carolina farms and one restaurant. Isolation was accomplished by culture of flies in alkaline peptone water followed by identification with Aeromonas-specific PCR using novel primers (APW–PCR). All isolates cultured from houseflies were identified as A. caviae by biochemical characteristics and direct sequencing ∼ 800 bp of the 16S rRNA gene. Aeromonas caviae was detected in 78% (272/349) dairy farm flies, 55% (54/99) pig farm flies and 39% (77/200) restaurant flies. Faeces from cows and pigs at the farms also were positive for A. caviae (58% and 100%, respectively). The APW–PCR method provided a rapid, convenient way to identify A. caviae from faeces and houseflies that contained hundreds of bacterial species.

Mastitis in dairy cows is a significant economic and animal welfare issue in the dairy industry. The bacterial pathogens responsible for infection of the mammary gland may be split into two main categories: major and minor pathogens. Infection with major pathogens generally results in clinical illness or strong inflammatory responses and reduced milk yields, whereas minor pathogen infection is usually subclinical. Previous investigations have considered the transmission of these pathogens independently. Experimental evidence has shown cross-protection between species of pathogens. In this study a mathematical model for the coupled transmission of major and minor pathogens along with their interaction via the host was developed in order to consider various methods for controlling the incidence of major pathogen infection. A stability analysis of the model equilibria provides explanations for observed phenomena and previous decoupled modelling results. This multispecies model structure has provided a basis for quantifying the extent of cross-protection between species and assessing possible control strategies against the disease.

The purpose of this study was to investigate carriage of intestinal spirochaetes by selected population groups in Western Australia. Stool specimens from 293 rural patients with gastrointestinal disorders, and from 227 healthy migrants from developing countries were cultured. Spirochaete isolates were identified using PCR, and typed by pulsed field gel electrophoresis (PFGE). Brachyspira aalborgi was not isolated. Brachyspira pilosicoli was recovered from 15 rural patients, all Aboriginal. Prevalence was 9·9% in 151 Aboriginals and 0% in 142 non-Aboriginals. Carriage of B. pilosicoli amongst migrants was 10·6% (24/227). Carriage was significantly increased in Aboriginal children aged 2–5 years (P = 0·0027) and in migrant individuals from the Middle East and Africa (P = 0·0034). Carriage was significantly associated with detection of faecal protozoa in both Aboriginals (P = 0·0021) and migrants (P = 0·012). PFGE results indicated that the B. pilosicoli strains were genetically diverse.

Foxes harbouring E. multilocularis represent an important source for human infection with this parasite which causes alveolar echinococcosis. To minimize the risk of human infection, a control study was conducted to reduce the prevalence of E. multilocularis-infection in foxes in an focal endemic area of 5000 km2. Foxes were given access to baits containing 50 mg praziquantel. Twenty baits per km2 were distributed by airplane during 14 campaigns. The effects of control measures were monitored by parasitological examination of 9387 foxes shot before and during the control trial. A distinct reduction of the prevalence of E. multilocularis was observed for both, the initially endemic area and the low-endemic periphery. The effect was more pronounced in adult than in juvenile foxes. Under control conditions, the risk area decreased in size. However, an eradication of the parasite was not reached with the chosen strategy.

In order to clarify the failure to isolate Shigella spp. by direct plating, we compared frequencies of Shigella spp. isolation by direct plating and by plating after enrichment in selenite broth. A total 67 strains were isolated in this study. The strains of 38 (56·7%) were isolated only by direct plating, and 25 (37·3%) strains were isolated by both direct plating and after enrichment. Four strains (6·0%) were isolated after enrichment but not by direct plating. Since 6% of isolated Shigella spp. were not isolated by direct plating, we recommend that direct plating and additional isolations from selenite broth should be performed. The significance concerning reduction of concentration of sodium selenite in enrichment broth is discussed.