Recently, two independent research teams reported evidence of infection with SARS-like coronaviruses in insectivorous horseshoe bats (genus Rhinolophus) in China [1, 2]. SARS emerged in China in 2002, and eventually infected over 8000 people around the world, killing about 10% of them. Early epidemiological studies suggested that the human disease may have originated in Chinese live-animal food markets, and the hunt for a source of the virus quickly identified apparently healthy Himalayan palm civets (Paguma larvata) as prime suspects [3]. Other studies, however, failed to find any evidence of widespread infection in civets [4] or a variety of other animals traditionally used as food in China. Rather, palm civets, like human beings, seem to be only accidental hosts of the virus, becoming infected, again like people, when mixed with other species in markets. More structured hunts for the reservoir continued, although not before thousands of palm civets had been slaughtered.

Rotaviruses are a major cause of hospitalizations for acute gastroenteritis in developed countries. This review shows the burden of rotavirus disease in <5-year-old children in Europe. An estimated 72000–77000 hospitalizations for community-acquired rotavirus disease occur annually in the 23 million under-fives living in the European Union (EU-25), with a median cost of €1417 per case. Annual hospitalization incidence rates range from 0·3 to 11·9/1000 children <5 years old (median 3/1000). The median proportion of hospital-acquired rotavirus disease among all cases of hospitalization for rotavirus disease is estimated to be 21%. Countries of the EU-25 require information on the burden of rotavirus disease to support introduction of rotavirus vaccines. Data on cases treated at home, medical visits, and emergency wards as well as rotavirus-associated deaths are limited. To fully evaluate the impact and effectiveness of rotavirus vaccination programmes in Europe, additional epidemiological studies will be critical and desirable.

Since 2002, the burden of norovirus (NoV) infection in Ireland has increased. Outbreaks in institutional settings are the most common causing widespread disruption to health service delivery. This is the first national study of NoV in the Republic of Ireland and its aim was to identify the major NoV strains circulating in Ireland over a 13-month period between November 2003 and November 2004, inclusive. A prospective study screened faecal samples (n=478) for NoV RNA. Positive samples (n=116) were further analysed by a second PCR, targeted to the orf1/orf2 junction of the virus. Phylogenetic analysis was based on sequence alignments of this domain. GII/4 viruses represented 92·2% of sequences, 2·7% were GII/2, GII/3 and GGIIB cluster-like strains. The remaining 5·2% were of GI origin. NoV was detectable throughout the study period, although two peaks of infection were observed. The majority of infections were caused by a range of closely related GII/4 NoV strains.

The aim of this study was to investigate the relationship between dog and cat ownership and gastroenteritis in young children. A diary study of 965 children aged 4–6 years living in rural or semi-rural South Australia was undertaken. Data were collected on pet ownership, drinking water and other risk factors for gastroenteritis. Overall 89% of households had pets and dog ownership was more common than cat ownership. The multivariable models for gastroenteritis and pet ownership indicated that living in a household with a dog or cat was associated with a reduced risk of gastroenteritis (adj. OR 0·71, 95% CI 0·55–0·92; OR 0·70, % CI 0·51–0·97 respectively). This paper adds to the evidence that pets are not a major source of gastroenteritis in the home and lends support to the health benefits of pet ownership. However, this must be weighed against the potential negative consequences, such as dog bites, particularly for this age group.

Large outbreaks of giardiasis caused by person-to-person transmission, or a combination of transmission routes, have not previously been reported. A large, prolonged giardiasis outbreak affected families belonging to a country club in a suburb of Boston, Massachusetts, during June–December 2003. We conducted a retrospective cohort study to determine the source of this outbreak. Giardiasis-compatible illness was experienced by 149 (25%) respondents to a questionnaire, and was laboratory confirmed in 97 (65%) of these cases. Of the 30 primary cases, exposure to the children's pool at the country club was significantly associated with illness (risk ratio 3·3, 95% confidence interval 1·7–6·5). In addition, 105 secondary cases probably resulted from person-to-person spread; 14 cases did not report an onset date. This outbreak illustrates the potential for Giardia to spread through multiple modes of transmission, with a common-source outbreak caused by exposure to a contaminated water source resulting in subsequent prolonged propagation through person-to-person transmission in the community. This capacity for a common-source outbreak to continue propagation through secondary person-to-person spread has been reported with Shigella and Cryptosporidium and may also be a feature of other enteric pathogens having low infectious doses.

In April 2002, five cases of fascioliasis were diagnosed in Tourcoing. A case-finding and a case-control study were carried out to identify the source of the outbreak and take appropriate control measures. Eighteen cases were identified through the medical laboratories carrying out serology for fascioliasis. Fourteen cases and 23 controls, identified by the physicians of the cases, were interviewed on symptoms of the disease and their consumption of uncooked plants. Cases were more likely than controls to have eaten commercialized raw watercress (OR 86·7, P<0·001) and 13 (93%) of the cases reported its consumption. A single producer common to all cases was identified. The inspection of his watercress beds showed a lack of protection against Lymnaea truncatula. This outbreak of fascioliasis due to commercialized watercress indicates that actual sanitary regulations do not allow for the efficient prevention of infestation of watercress production in France.

Stringency of milk pasteurization has been established on requirements for Coxiella burnetii as being the most heat-resistant organisms of public heath significance. This paper discusses the estimation of the efficiency of pasteurization time/temperature combinations as required in regulations for food safety. Epidemiological studies have been interpreted as C. burnetii being a significant pathogen causing clinical disease through ingestion of milk. The paper examines the evidence and challenges the designation of C. burnetii as a foodborne pathogen. Consequently it questions the need for pasteurization parameters to be established on its heat resistance characteristics.

Worldwide, early detection systems have been used in public health to aid the timely detection of increases in disease reporting that may be indicative of an outbreak. To date, their application to animal surveillance has been limited and statistical methods to analyse human health data have not been viewed as being applicable for animal health surveillance data. This issue was investigated by developing an early detection system for Salmonella disease in British livestock. We conclude that an early detection system, as for public health surveillance, can be an effective tool for enhanced surveillance. In order to implement this system in the future and extend it for other data types, we provide recommendations for improving the current data collection process. These recommendations will ensure that quality surveillance data are collected and used effectively to monitor disease in livestock populations.

The antibiogram pattern and seasonal distribution of Salmonella serotypes were analysed retrospectively over a 6-year period from January 1999 to December 2004. Blood cultures received in the Bacteriology Laboratory were processed by standard procedures and the Salmonella spp. isolates were identified with specific antisera and standard biochemical tests. Antimicrobial susceptibility testing was carried out by a standard disc diffusion method and the minimum inhibitory concentration (MIC) of ciprofloxacin for 332 representative Salmonella isolates was determined by E test. Salmonella Typhi (75·7%) was the predominant serotype among 830 Salmonella spp. isolated during the study period followed by S. Paratyphi A (23·8%). The maximum number of enteric fever cases occurred during April–June (dry season) followed by July–September (monsoon season). There was a decrease in multidrug-resistant (MDR) S. Typhi, but MDR S. Paratyphi A isolates increased. There was also a dramatic increase in nalidixic acid-resistant isolates. All isolates were susceptible to third-generation cephalosporins and ciprofloxacin except one S. Typhi strain which demonstrated high-level ciprofloxacin resistance with a MIC of 16 μg/ml. A knowledge of the seasonal distribution and antibiotic resistance pattern of Salmonella in a particular geographical region is helpful in the delineation of appropriate control measures required for prevention of enteric fever.

Salmonella enterica serovar Enteritidis (SE) is a major foodborne pathogen primarily causing human infection through contaminated chicken eggs. To understand how SE survives in chicken egg albumen, we systematically and quantitatively analysed the survival properties of SE in egg albumen and identified factors affecting its survival. Survival assays of SE in egg indicate that egg albumen restricted the growth of SE. A major factor that controlled SE's growth in egg albumen was iron restriction, since egg albumen supplemented with iron allowed SE to grow, and iron acquisition mutants of SE showed decreased survival in egg albumen. In addition, low pH of albumen, high concentrations of bacteria and low incubation temperatures of bacteria with albumen facilitates the survival of SE. Our results suggest that egg albumen uses multiple mechanisms to control SE including iron limitation, surface interaction and possible enzymatic activities.

Eighty-one adult patients with Salmonella enterica serotype Choleraesuis (S. Choleraesuis) bacteraemia treated at a university hospital from 1996 to 2004 were evaluated. Multivariate analysis with a logistic regression model was used to characterize risk factors for primary bacteraemia and mycotic aneurysm and to determine the association of clinical characteristics of patients based on ciprofloxacin susceptibility of the causative organism. The incidence per 100000 discharges was 0·76 in 1996 and 3·9 in 2004. The overall rate of ciprofloxacin resistance among these isolates was 59% (87 isolates) and the annual rate increased with time from 0% prior to 2000 to 80% in 2004. Among these patients, 48 (59%) had primary bacteraemia and 13 (16%) had secondary bacteraemia with mycotic aneurysm. Seventy (86%) patients had fever at presentation, 22 (27%) developed shock during hospitalization, and eight (10%) died of S. Choleraesuis bacteraemia. Patients with immunocompromised conditions had a higher risk of developing primary bacteraemia (OR 18·442, P<0·001). Hypertension (OR 15·434, P=0·002) and male gender (OR 7·422, P=0·039) were associated with mycotic aneurysm. Patients with mycotic aneurysm were more frequently infected with ciprofloxacin-susceptible isolates (P=0·028) and ciprofloxacin-susceptible isolates were also more frequently associated with recurrent infection than ciprofloxacin-resistant isolates (P=0·038). The incidence of S. Choleraesuis bacteraemia has increased in the past 8 years, and this increase is associated with the upsurge of ciprofloxacin-resistant isolates.

During recent years a pandemic clone of Vibrio parahaemolyticus has emerged. Isolates of this clone are distributed among several serotypes, but are genotypically related. In the present study, a phenotyping method (biochemical fingerprinting) was used to characterize pandemic and non-pandemic isolates belonging to V. parahaemolyticus. It was found that the pandemic isolates showed a high level of phenotypic homogeneity and a majority of the pandemic isolates belonged to the same biochemical phenotype, whereas non-pandemic V. parahemolyticus isolates were more heterogeneous. In conclusion, biochemical fingerprinting of V. parahaemolyticus can be used as a first screening method to differentiate between pandemic and non-pandemic isolates of V. parahaemolyticus.

We determined the prevalence and risk factors of H. pylori infection among 197 healthy 3- to 5-year-old Israeli Arab children, in a population under socioeconomic and environmental transition. Data on the socioeconomic and environmental characteristics were obtained by personal interviews. The presence of H. pylori infection was identified using an ELISA kit for detection of H. pylori antigens in stool specimens. The prevalence rate of H. pylori infection was 49·7% (95% CI 42·8–56·67). It varied significantly among the different villages. In the univariate analysis stratified by village, the risk of infection increased according to household crowding, number of siblings younger than 5 years and siblings' H. pylori positivity. In the multivariate analysis the village of residence and siblings' H. pylori positivity were the only variables that remained strongly associated with H. pylori infection. In a population such as that described in this study the socioeconomic and living conditions are major risk factors of H. pylori infection and the intra-familial transmission of H. pylori in early childhood has an important role.

In this study, we used plasmid profile analysis, XbaI macrorestriction with pulsed-field gel electrophoresis (PFGE), and PCR of the ipaH gene, to study the molecular characteristics of 183 Shigella spp. isolated during May 2000 to April 2003 from rectal swabs of patients with watery and/or bloody diarrhoea in a new industrialized area of Thailand. Among the 183 isolates, 167 were S. sonnei and 16 were S. flexneri. For plasmid profile analysis, the 183 isolates revealed 16 different plasmid patterns, designated patterns A to P. The sizes of the plasmid bands were: 6, 5·5, 5, 4·5, 4, 3·25, 2·75, 2·5, 2, 1·75, 1·5 and/or 1·25 kb. The frequency of each plasmid band was 4·5 kb (165 isolates), 3·25 kb (161 isolates), 5·5 kb (129 isolates), 1·75 kb (121 isolates), 1·5 kb (35 isolates), 5 kb (21 isolates), 2 kb (16 isolates), 2·75 kb (12 isolates), 1·25 kb (9 isolates), and 6 kb (8 isolates). PFGE analysis revealed 45 different XbaI macrorestricted DNA banding patterns which could be grouped into 11 groups. All the isolates gave PCR amplicons of the ipaH gene. Plasmid profile analysis and PFGE are powerful tools for differentiation of the Shigella spp. This study provides important data on the molecular characteristics of Shigella isolates in Thailand, which could be useful as an epidemiological baseline for identifying relationships with strains that may emerge in the future.

Settings of fingerprint-type analysing computer software were optimized for analysis of enterohaemorrhagic Escherichia coli (EHEC) pulsed-field gel electrophoresis (PFGE) patterns. Under the lowest values of parameters, maximum value of similarities calculated using the Dice coefficient were obtained between PFGE patterns from one EHEC strain on the same gel when reference lanes for calibration of distortions during electrophoresis were set to every fourth lane. PFGE patterns of 15 EHEC strains on different gels were investigated. Similarity values calculated using the Pearson product-moment correlation coefficient (Pearson correlation) were significantly higher than those using the Dice coefficient with optimal values of parameters determined by the program (P<0·01). When PFGE patterns of 45 EHEC strains were analysed by the computer program, EHEC strains from one mass outbreak and three intra-family outbreaks were each clustered and the similarity values within the clusters were >90% using Pearson correlation.

To clarify whether prevalence or special pathogenicity is more important in determining urinary tract infection (UTI) causation, we compared the biotype, phylogenetic group, and virulence genes of Escherichia coli urine strains from 11 women with acute lower UTI with those of the host's dominant intestinal E. coli strain(s). Twenty-one unique E. coli clones were identified. For three women, the single faecal clone identified was also the host's urine clone, whereas for eight women faecal samples yielded 1 or 2 distinct non-urine clones (total, n=10), either with (n=3) or without (n=5) the concurrent urine clone. The eight urine clones from the latter eight women exhibited significantly greater inferred virulence, according to virulence gene content and phylogenetic background, than did the hosts' 10 corresponding ‘faecal only’ clones. In contrast, the three urine clones that were detected as the host's sole faecal clone exhibited significantly lower inferred virulence than the other eight urine clones, and were statistically indistinguishable from the 10 ‘faecal only’ clones. In conclusion, special pathogenicity is an important determinant of UTI pathogenesis in women, although prevalence may occasionally allow less virulent strains to cause UTI.

Outbreaks of enteric disease associated with exposure to live animals on exhibit have occurred with increasing frequency in recent years. Possibly the most important pathogen causing such outbreaks is Escherichia coli O157:H7, because of the serious illness it can cause. Hand hygiene is consistently protective against disease among persons exposed to animals implicated in these outbreaks. Livestock barns have limited hand-washing facilities, therefore a waterless hand-sanitizing gel would be a potentially preventive measure readily available to visitors and animal exhibitors. This study compared the reduction of bacterial counts on hands of animal exhibitors when soap and water was used or when an ethanol-based hand gel was used after animal handling. Participants were youth and adults involved with showing livestock. The sanitation methods were similar in reducing the total bacteria and coliform counts on the hands of the participants (Wilcoxon rank sum test P values 0·12 and 0·69 respectively).

Nyanza Province, Kenya is characterized by poor water quality and high diarrhoea prevalence. To address these problems, nurses in a maternal and child health clinic in Homa Bay, Kenya were trained in household water chlorination with a locally available, social marketed product, and in six steps of proper hand washing. They were asked to communicate this information to their clients. Interviews immediately following the training by nurses were conducted on 220 clients, of whom 168 (76%) reported being taught both procedures during their clinic visit. After 2 weeks, free chlorine residuals were present in stored drinking water in 67 out of 98 (68%) clients' homes and, 1 year later, in 36 out of 51 (71%) clients' homes. After 2 weeks, all six hand-washing steps were correctly demonstrated by 41 (44%) out of 93 clients, and by 17 out of 51 (34%) 1 year later. This brief, practical intervention shows promise for vulnerable populations.

The aims were to (1) investigate the aetiology of probable meningococcal disease, where a clinical diagnosis is made in the absence of laboratory data, and (2) evaluate the impact of the Men C vaccination programme in England and Wales. Multiple linear regression analyses were carried out using data reported to Enhanced Surveillance of Meningococcal Disease (ESMD) and laboratory reports of isolates of organisms causing symptoms that mimic meningococcal disease. Confirmed meningococcal disease appeared to be a significant predictor of probable disease. Thus, an additional reduction in meningococcal disease attributable to the serogroup C vaccination campaign was evident in probable disease over and above that observed in confirmed cases alone. Enteroviruses were a significant contributor to cases of probable meningitis and influenza appeared to be a significant contributor to probable cases of septicaemia. This analysis confirms the success seen following the Men C vaccination campaign and gives an indication of the aetiologies of other causes of probable meningitis and septicaemia reported to ESMD.

Meningitis epidemics have a strong environmental component in Africa with the most severe epidemics occurring in the Sahelian region known as the Meningitis Belt. The objective of this study is to evaluate an ecological model based on absolute humidity and land cover type to predict the location of these epidemics. The risk model is evaluated prospectively based on epidemics occurring in Africa from January 2000 to April 2004. Seventy-one epidemics occurred during this time period affecting 22% of continental African districts. The model predicted their location with a sensitivity of 88%. The evaluation also suggests that epidemics may be extending south of the Sahel, which is consistent with environmental changes in the region. This model could be used to select priority areas for the introduction of the newly developed conjugate meningococcal vaccines. Further studies are needed to enhance our understanding of the complex relationship between meningitis epidemics and the environment.