Prevalence and incidence of toxoplasmosis: a retrospective analysis of mother-child examinations, Styria, Austria, 1995 to 2012.

In Austria, mandatory screening for the prevention of congenital toxoplasmosis stipulates a serological test for antibodies against Toxoplasma gondii as early as possible in pregnancy. In the case of a seronegative result, subsequent tests at intervals of 8 weeks are requested. We analysed serological data from Styria, an Austrian federal state, to determine the seroprevalence and incidence of Toxoplasma infections. The study included 353,599 tests from 103,316 women during 158,571 pregnancies from 1995 to 2012. The age-adjusted seroprevalence decreased from 43.3% in 1995 to 31.5% in 2012, with a yearly decline of 0.84% (95% confidence interval (CI): 0. 79 -0.88). The intergravid incidence showed an annual decrease of 4.2%. The average yearly incidence of intragravid and intergravid seroconversions was 0.52% (95% CI 0.45-0.61) and 0.72% (95% CI 0.67-0.77), respectively. If the difference between these rates (p < 0.001) can be explained by the effect of primary prevention such as avoiding raw meat and taking hygiene precautions when encountering cats or preparing vegetables, only ca two of seven (28%) infections were avoided by hygiene measures taken by pregnant women. Primary prevention may therefore have its limits.

Multiple-locus variable-number tandem repeat analysis for subtyping of Salmonella enterica subsp. enterica serovar Enteritidis.

Salmonella enterica subsp. enterica serovar Enteritidis is a major food-borne pathogen that caused most of Salmonella infections worldwide. S. Enteritidis phage type 4 (PT4) especially presents a real challenge for the classical typing methods. We developed a simple multiple-locus variable-number tandem repeat analysis (MLVA) assay based on three hypervariable variable-number tandem repeat (VNTR) loci for subtyping of Salmonella Enteritidis. Testing an arbitrary chosen strain collection of 110 S. Enteritidis isolates, comprising PTs 4, 8, and 21, the MLVA assay yielded a higher discriminatory power, corresponding to a Simpson's index of diversity (ID) of 0.91, when compared to pulsed-field gel electrophoresis (PFGE) which had a Simpson's ID of 0.41. To simplify interpretation of results, we developed a VNTR allele code based on the repeat unit number. This code can easily be exchanged. In conclusion, MLVA is a promising new tool to investigate outbreaks of S. Enteritidis and constitutes a useful addition to the current phage typing scheme.

Antimicrobial drug resistance in human nontyphoidal Salmonella isolates in Europe 2000-2004: a report from the Enter-net International Surveillance Network.

A 5-year survey, from 2000 to 2004, of results of antimicrobial susceptibility testing for 11 antimicrobials for 134,310 isolates of nontyphoidal salmonellas from cases of human infection in 10 European countries has demonstrated an overall increase in the occurrence of resistance, from 57% to 66% over the period of study. In contrast, multiple resistance (to four or more antimicrobial drugs) has declined from 18% to 15%. The most significant increase in resistance has been to nalidixic acid (14% to 20%), particularly in Salmonella enterica serovar Enteritidis (10% to 26%), the most common serovar. For England and Wales this increase has for the most part been attributed to infections linked to contaminated eggs originating outside the United Kingdom. For Salmonella Typhimurium, the second most prevalent serovar, there has been an overall decline in the occurrence of resistance to ampicillin, chloramphenicol, and tetracyclines, attributed to a decline in the occurrence of multiresistant Salmonella Typhimurium DT 104. For Salmonella Virchow, a serotype with a predilection for invasive disease, there has been a substantive increase in resistance to most antimicrobials, attributed to the spread of drug-resistant strains associated with poultry. Because of the widespread importation of foods, it is important that controls to reduce the emergence and spread of drug-resistant strains of Salmonella are internationally implemented.

Lessons learned from a Salmonella enteritidis phage type 4 outbreak in Austria, 2005.

An outbreak of gastroenteritis due to Salmonella Enteritidis phage type 4 occurred in people who attended a traditional hunting festivity in a small village in western Austria 6 through 11 November 2005. Of approximately 250 attendees, 227 had consumed dishes offered at the festival, and of these consumers 35 persons fulfilled the outbreak case definition (attack rate of 15.4%). Spätzle (traditional pastalike side dish) was most likely the contaminated part of the incriminated main course (relative risk of 18.9, 95% confidence interval of 4.6 to 76.7; P < 0.001). Thirteen eggs that remained from the preparation of the spätzle were negative for Salmonella when tested individually without shell disinfection, as were 1200 eggs collected at the egg production plant and examined with shell disinfection. The back-traced egg production farm had been initially certified as Salmonella free by a voluntary quality control program. However, an intensified environmental investigation of the incriminated egg production farm performed in the first quarter of 2006 and based on an appropriate method of sampling revealed Salmonella Enteritidis phage type 4 in 4 of 13 flocks. Although a combination of epidemiological and microbiological investigations allowed elucidation of the mode of spread, no restrictions were placed on the incriminated flocks of laying hens. These flocks were kept in production until they were stalled out due to age in August 2006. In June 2006, a cluster of 23 cases of Salmonella Enteritidis phage type 6 infection was again associated with this egg production farm. Evidence provided by epidemiological analyses is often disregarded by decision makers. However, negative results from microbiological testing of food involved in an outbreak are often weighted as strong evidence against a causal association between that food and the outbreak.

Invasive meningococcal disease in Austria 2002: assessment of completeness of notification by comparison of two independent data sources.

AIM OF THE STUDY: The notified incidence of meningococcal disease in European countries varies from <1 case per 100,000 inhabitants to approximately 7 cases per 100,000. Assessing the true burden of disease is important for setting priorities in health services and for estimating the benefit of interventions such as vaccination. Completeness and timeliness of reporting is also essential for the early recognition of outbreaks. The objective of this study was to assess the completeness of surveillance data on invasive meningococcal disease in Austria at the National Reference Center for Meningococci for the year 2002. METHODS: The data stored at the reference center was compared with an independent database containing the main diagnosis documented in the obligatory hospital discharge dataset of all Austrian hospitals (coded in ICD-10 since 2001). All mismatches were reviewed in order to exclude possible errors and identify true cases of meningococcal disease that had not been reported to the reference center. The number of cases not recorded by either data source was estimated using the capture-recapture method. RESULTS: The first comparison of the two data sources identified 50 cases not registered at the national reference center. Screening of the ICD codes from these 50 patients through the hospitals reduced the number of under-reported cases to 10, of which 6 showed symptoms compatible with meningococcal disease, although microbiological confirmation was missing. Re-evaluation of the case histories of these 6 patients by a clinical expert for meningococcal disease identified them as probable cases. The main reason for correction of the diagnosis in 27 cases was an obvious coding error: these patients had been treated in hospitals for illnesses not related to meningococcal disease. In 72 cases, the two databases were in agreement. Eleven cases of meningococcal disease were notified solely to the national reference center. Addition of the newly recognized cases of invasive meningococcal disease increased the total number of cases from 83 (incidence, 1.03/100,000) to 93 (incidence, 1.16/100,000). Estimation of the "true" number of cases of meningococcal disease, using the capture-recapture method, gave a final total of 95 cases (95% CI, 93-98) and an incidence of 1.18/100,000. The completeness (sensitivity) of the original notification at the national reference center was therefore 87.4% (83 of 95 cases). CONCLUSION: All probable cases of meningococcal disease, even those (still) lacking microbiological confirmation, should be reported to the public health authorities as soon as possible, in order to ensure the necessary prompt prophylactic action (e.g., chemoprophylaxis).

An Austrian outbreak of Salmonella enteritidis phage type 36 in 2004.

In June 2004, an egg packing station was epidemiologically incriminated as possibly distributing the vehicle of the Salmonella enterica subsp. enterica ser. Typhimurium definitive type (DT) U291 outbreak which began in September 2003 and--as of June 2004 affected more than 100 persons all over Austria and 8 German tourists. A total of 68 egg producing farms were screened for salmonella. Whereas all samples tested negative for S. Typhimurium DT U291, one batch of laying hens was identified as being heavily contaminated with a rare Salmonella enterica subsp. enterica ser. Enteritidis phage type, namely PT 36. This phage type was cultured from 6 of 7 swabs from pooled fecal samples (drag swabs), from 1 of 4 samples of pooled yolks, and from 7 of 11 hens tested (ovaries, liver and intestinal content pooled per hen). In 2004, a total of 36 culture-confirmed human PT 36 infections (19 manifest cases, 12 asymptomatic carriers, and 5 excreters with unknown clinical status) were documented in 4 of the 9 Austrian provinces. It was possible to demonstrate that eggs from this single farm were the probable source of infection for 30 of 31 culture-confirmed human infections. Only in the case of one patient, who regularly purchased eggs at the local market, could no connection to the farm be proven due to inability to trace the market's egg source. The PT 36 outbreak ceased after elimination of the contaminated flock. This episode underlines the considerable potential of adequate epidemiological and microbiological investigations of food-borne outbreaks to improve prevention and control of communicable diseases. The source of the S. Typhimurium DT U291 outbreak--which initially prompted this investigation--is still not identified and accounts for more than 300 human cases until August 2005.

An outbreak of Norovirus infection affecting an Austrian nursing home and a hospital.

On November 9, 2004, a resident in a nursing home experienced a severe episode of vomiting in the dining room, in the presence of most of the other residents and members of staff. Following that episode, 17 of the 23 (73.9%) other residents and 7 of the 18 (38.9%) staff members fell ill with diarrhea and/or vomiting in the period up to November 17. A second cluster of gastroenteritis occurred between November 11 and 28, 2004, in a nearby hospital to which eight cases among the nursing home residents had been referred. Ten of 46 (21.7%) other hospital patients and 18 of 60 (30%) members of the hospital staff suffered from vomiting or diarrhea. Epidemiological and laboratory investigations proved a causal relationship between the two institutional clusters of short-lived gastroenteritis related by time and place, and identified Norovirus genotype GGII.4 (Jamboree-like) as the causative pathogen. Control measures for Norovirus, based on epidemiological and clinical features of the outbreak, were effectively implemented in the nursing home without waiting for virological confirmation. At the hospital, specific measures were not implemented until after virological confirmation of the causative agent, by which time 16 cases had already occurred. In a suspected Norovirus outbreak it is of great importance -- especially within closed and semiclosed settings -- to implement control measures as soon as possible, even before laboratory confirmation of the agent.

Occurrence of antimicrobial resistance among bacterial pathogens and indicator bacteria in pigs in different European countries from year 2002 - 2004: the ARBAO-II study.

BACKGROUND: The project "Antibiotic resistance in bacteria of animal origin - II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003-05. The aim of this project was to establish a program for the continuous monitoring of antimicrobial susceptibility of pathogenic and indicator bacteria from food animals using validated and harmonised methodologies. In this report the first data on the occurrence of antimicrobial resistance among bacteria causing infections in pigs are reported. METHODS: Susceptibility data from 17,642 isolates of pathogens and indicator bacteria including Actinobacillus pleuropneumoniae, Streptococcus suis and Escherichia coli isolated from pigs were collected from fifteen European countries in 2002-2004. RESULTS: Data for A. pleuropneumoniae from infected pigs were submitted from five countries. Most of the isolates from Denmark were susceptible to all drugs tested with the exceptions of a low frequency of resistance to tetracycline and trimethoprim - sulphonamide. Data for S. suis were obtained from six countries. In general, a high level of resistance to tetracycline (48.0 - 92.0%) and erythromycin (29.1 - 75.0%) was observed in all countries whereas the level of resistance to ciprofloxacin and penicillin differed between the reporting countries. Isolates from England (and Wales), France and The Netherlands were all susceptible to penicillin. In contrast the proportion of strains resistant to ciprofloxacin ranged from 12.6 to 79.0% (2004) and to penicillin from 8.1 - 13.0% (2004) in Poland and Portugal. Data for E. coli from infected and healthy pigs were obtained from eleven countries. The data reveal a high level of resistance to tetracyclines, streptomycin and ampicillin among infected pigs whereas in healthy pigs the frequency of resistance was lower. CONCLUSION: Bacterial resistance to some antimicrobials was frequent with different levels of resistance being observed to several antimicrobial agents in different countries. The occurrence of resistance varied distinctly between isolates from healthy and diseased pigs, with the isolates from healthy pigs generally showing a lower level of resistance than those from diseased pigs. The study suggests that the choice of antimicrobials used for the treatment of diseased animals should preferably be based on knowledge of the local pattern of resistance.

Prevalence of antimicrobial resistance among bacterial pathogens isolated from cattle in different European countries: 2002-2004.

BACKGROUND: The project "Antibiotic resistance in bacteria of animal origin - II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003-2005, with the aim to establish a continuous monitoring of antimicrobial susceptibility among veterinary laboratories in European countries based on validated and harmonised methodologies. Available summary data of the susceptibility testing of the bacterial pathogens from the different laboratories were collected. METHOD: Antimicrobial susceptibility data for several bovine pathogens were obtained over a three year period (2002-2004). Each year the participating laboratories were requested to fill in excel-file templates with national summary data on the occurrence of antimicrobial resistance from different bacterial species.A proficiency test (EQAS - external quality assurance system) for antimicrobial susceptibility testing was conducted each year to test the accuracy of antimicrobial susceptibility testing in the participating laboratories. The data from this testing demonstrated that for the species included in the EQAS the results are comparable between countries. RESULTS: Data from 25,241 isolates were collected from 13 European countries. For Staphylococcus aureus from bovine mastitis major differences were apparent in the occurrence of resistance between countries and between the different antimicrobial agents tested. The highest frequency of resistance was observed for penicillin. For Mannheimia haemolytica resistance to ampicillin, tetracycline and trimethoprim/sulphonamide were observed in France, the Netherlands and Portugal. All isolates of Pasteurella multocida isolated in Finland and most of those from Denmark, England (and Wales), Italy and Sweden were susceptible to the majority of the antimicrobials. Streptococcus dysgalactiae and Streptococcus uberis isolates from Sweden were fully susceptible. For the other countries some resistance was observed to tetracycline, gentamicin and erythromycin. More resistance and variation of the resistance levels between countries were observed for Escherichia coli compared to the other bacterial species investigated. CONCLUSION: In general, isolates from Denmark, England (and Wales), the Netherlands, Norway, Sweden and Switzerland showed low frequencies of resistance, whereas many isolates from Belgium, France, Italy, Latvia and Spain were resistant to most antimicrobials tested. In the future, data on the prevalence of resistance should be used to develop guidelines for appropriate antimicrobial use in veterinary medicine.

Occurrence of Salmonella enterica serovar Dublin in Austria.

In Austria, Salmonella enterica serovar Dublin, a bovine-adapted serovar, rarely causes human infections. In the year 2000, Austria was within the European mean with an incidence of 0.1 per million inhabitants. Our data show that the vast majority of all Austrian serovar Dublin infections can be traced to two Tyrolian districts. This concentration of cases can be explained by a particularly traditional aspect of cattle farming in Tyrol, the alpine pasture. There is increased risk of cross-infection due to the communal keeping of animals from various farms. Infected cattle are a source of infection for people, and contagion usually occurs from eating beef and drinking cow's milk. Using pulsed-field gel electrophoresis and automated ribotyping, 3 out of 5 available isolates from human infections could be traced to characteristic Tyrolian S. Dublin clones. Bacteriological screening of herds with a known history of S. Dublin infection would be a start to prevent future contamination of alpine pastures through latently infected cattle excreting potentially infectious feces. Bacteriological screening for fecal carriage before the return of cattle from pastures known to be connected with infections could prevent cross-contamination of large mixed herds.