Molecular profile and epidemiological traits of Streptococcus suis isolated from diseased pigs in western Canada reveal multiple-serotype infection: Implications for disease control.

Objective: Streptococcus suis is a major agent of disease in modern swine operations, linked to increased mortality, treatment costs, and secondary infections. Although it is ubiquitous in swine, only a fraction of pigs develop clinical disease. The goals of this study were to profile isolates obtained from diseased pigs in western Canada and to investigate potential associations with disease severity. Procedure: Isolates of S. suis (n = 128) from 75 diagnostic submission and 63 premises were paired with epidemiological surveys completed by submitting practitioners (n = 22). Whole-genome sequencing was used to type isolates. Results: The most prevalent serotypes identified were 1/2 (7.8%, 10/128), 2 (9.3%, 12/128), 3 (9.3%, 12/128), and 7 (7.8%, 10/128); and sequence types 28 (17%, 23/128) and 839 (14%, 19/128). There was no association between serotype or sequence type and organ source or barn location. Approximately 74% (14/19) of the premises had diseased animals colonized by > 1 S. suis serotype, but only 1 pig was simultaneously infected with multiple serotypes and sequence types. Serotype distribution from diseased pigs in western Canada differed from that of those in other geographic regions. Conclusion: Infection of diseased pigs by multiple serotypes should be considered when disease control strategies are implemented. No association between S. suis type and isolation organ was identified.

Le profil moléculaire et les caractéristiques épidémiologiques de Streptococcus suis isolés de porcs malades dans l'ouest du Canada révèlent une infection à sérotypes multiples : implications pour la maitrise de la maladie. Objectif: Streptococcus suis est un agent pathogène majeur dans les exploitations porcines modernes, lié à une mortalité accrue, aux coûts de traitement et aux infections secondaires. Bien qu'elle soit omniprésente chez le porc, seule une fraction des porcs développe une maladie clinique. Les objectifs de cette étude étaient de dresser le profil des isolats obtenus à partir de porcs malades dans l'ouest du Canada et d'étudier les associations potentielles avec la gravité de la maladie. Procédure: Des isolats de S. suis (n = 128) provenant de 75 soumissions pour diagnostic et de 63 sites ont été associés à des enquêtes épidémiologiques réalisées auprès des praticiens soumettant les échantillons (n = 22). Le séquençage du génome entier a été utilisé pour typer les isolats. Résultats: Les sérotypes les plus répandus identifiés étaient 1/2 (7,8 %, 10/128), 2 (9,3 %, 12/128), 3 (9,3 %, 12/128) et 7 (7,8 %, 10/128); et les types de séquence 28 (17 %, 23/128) et 839 (14 %, 19/128). Il n'y avait aucune association entre le sérotype ou le type de séquence et la source d'organes ou l'emplacement de la ferme. Environ 74 % (14/19) des exploitations abritaient des animaux malades colonisés par > 1 sérotype de S. suis, mais 1 seul porc était infecté simultanément par plusieurs sérotypes et types de séquences. La répartition des sérotypes chez les porcs malades de l'ouest du Canada différait de celle des porcs d'autres régions géographiques. Conclusion: L'infection des porcs malades par plusieurs sérotypes doit être envisagée lors de la mise en oeuvre de stratégies de maitrise de la maladie. Aucune association entre le type de S. suis et l'organe d'isolement n'a été identifiée.(Traduit par Dr Serge Messier).

A walk-in clinic as an alternative approach to reaching non-attenders of the cervical cancer screening program in the North Denmark region-a pilot study.

INTRODUCTION: Up to 39% of women in Denmark do not participate regularly in the cervical cancer screening program and initiatives to increase participation are called upon. The primary aim of this study was to describe previous screening history and characteristics of women attending screening in a walk-in clinic. Furthermore, we wanted to investigate barriers to cervical cancer screening. MATERIAL AND METHODS: We designed a walk-in clinic that was open 2 days a week from 16.00 to 19.00 h, located in the Departments of Gynecology in the two main hospitals of the North Denmark Region. The main purpose of the clinic was cervical cancer screening and the study period was 5 months. Women who were not eligible for screening or had other health complaints were referred to their general practitioner. The women included in the study, filled out a questionnaire regarding educational and occupational status; their screening history was registered using data from the Danish Pathology Register. RESULTS: During the study period, 255 women visited the walk-in clinic. The final study population consisted of 249 women who met the inclusion criteria. Age range of participants was 23-77 years, with a median age of 45 years. The majority of the participants were currently employed (81%) or students (10%), the remaining being retired (5%) or unemployed (4%). Screening history showed that 138 (55.4%) of the women were on time for the screening or delayed less than 6 months compared to their recommended screening interval. Sixty-one women (24.5%) were delayed >6 months but <2 years. Fifty women (20.1%) were classified as non-attenders, with more than a 2-year delay in their screening. In the group of non-attenders, eight women had never been screened. Of the remaining 42 women, the median time since last screening was 8.2 years (range 5.0-25.3 years). CONCLUSIONS: Women attending the walk-in clinic tended to be primarily actively working or students (91%). All age groups in the screening population were represented. Screening history showed that 44.6% had not followed the recommended screening program.

Management of low-grade cervical cytology in young women. Cohort study from Denmark.

OBJECTIVE: Cytology findings of atypical squamous cells of unknown significance (ASCUS) or low-grade squamous intraepithelial lesion (LSIL) are common among women under 30, but evidence on best management strategy is insufficient. We therefore investigated how different management strategies used in Denmark influenced biopsy rates and detection of cervical intraepithelial neoplasia (CIN). METHODS: Register-based cohort study including Danish women aged less than 30 years and born 1980-95, with ASCUS/LSIL as their first abnormal cervical cytology in 2008-16. Rates and relative risks (RR) of biopsy and detection of CIN3+, CIN2 and < CIN2 during two years follow-up were compared between women referred directly to colposcopy after ASCUS/LSIL or undergoing additional testing, including mRNA or DNA test for high risk HPV or repeat cytology. RESULTS: 19,946 women with ASCUS and 19,825 with LSIL were included in the study of whom 92% had adequate information about follow-up. Among women referred directly to biopsy, CIN3+ was detected among 21%, CIN2 in 17%, while 62% had < CIN2. Repeating cytology after 6 months reduced the biopsy rate to 44% of which 53% had < CIN2. Biopsy rates with HPV test were 67% for DNA test, 77% with 14-type mRNA test and 58% with 5-type mRNA test. The detection of CIN3+ was somewhat higher, between 13% and 14% for the three HPV tests vs. 11% with repeat cytology. However, the detection of < CIN2 (not indicating treatment) also increased with RR 2.11 (95% CI 2.01-2.21) for 14-type mRNA test, 1.35 (95% CI 1.29-1.41) for 5-type mRNA test, and 1.86 (95% CI 1.76-1.97) with HPV DNA test. CONCLUSIONS: The choice of management strategy influences both the detection rate for severe lesions (CIN3+) and the proportion of women followed up for potentially insignificant findings.

Prevalence of high-risk human papillomavirus after HPV-vaccination in Denmark.

Vaccination against human papillomavirus (HPV) has been introduced as a public health initiative in many countries, including Denmark since October 2008. It is important to monitor postimplementation effectiveness of HPV-vaccination at the population-level. We studied HPV-prevalence after first invitation to screening at age 23 years in women offered the quadrivalent HPV-vaccine at the age of 14 years. Randomly selected screening samples from women born in 1994 in four out of five Danish regions were subjected to analysis for HPV in addition to routine cytology. Cobas4800 was used in all participating pathology departments. Data from a Danish prevaccination cross-sectional study using Hybrid Capture 2, and a Danish split-sample study using Cobas4800 were used for comparison. In the period from February 2017 to April 2019, 6233 screening samples from women born in 1994 were selected for HPV-analysis; 27 samples had no HPV-test and 3 samples had no HPV-diagnosis, leaving 6203 samples with an HPV-diagnosis. Prevalence of any high-risk (HR) HPV was 35%; only 0.9% were positive for vaccine HPV types 16/18 while the remaining 34% were positive for other HR HPV. When comparing with prevaccination prevalence data, HPV-16/18 decreased by 95%; RR = 0.05 (95% CI 0.04-0.06), while other HR HPV remained fairly constant; RR = 0.88 (95% CI 0.82-0.94) and RR = 0.95 (95% CI 0.88-1.03), respectively. One-third of women vaccinated as girls with the quadrivalent HPV-vaccine were HR HPV-positive at time of first invitation to screening. Vaccine HPV-types 16 and 18 were almost eliminated, while the prevalence of nonvaccine HR HPV-types remained constant.

Attention-deficit/hyperactivity disorder symptoms in children with surgically corrected Ventricular Septal Defect, Transposition of the Great Arteries, and Tetralogy of Fallot.

BACKGROUND: Children with complex CHD are at risk for psychopathology such as severe attention-deficit/hyperactivity disorder symptoms after congenital heart surgery. OBJECTIVE: The aim of this study was to investigate if children with Ventricular Septal Defect, Transposition of Great Arteries, or Tetralogy of Fallot have an increased occurrence of attention-deficit/hyperactivity disorder symptoms compared with the background population and to investigate differences between the three CHDs in terms of occurrence and appearance of attention-deficit/hyperactivity disorder symptoms. METHOD: A national register-based survey was conducted, including children aged 10-16 years with surgically corrected CHDs without genetic abnormalities and syndromes. The Attention-Deficit/Hyperactivity Disorder-Rating Scale questionnaires were filled in by parents and school teachers. RESULTS: In total, 159 out of 283 questionnaires were completed among children with CHDs and compared with age- and sex-matched controls. Children with CHDs had significantly increased inattention scores (p = 0.009) and total attention-deficit/hyperactivity disorder scores (p = 0.008) compared with controls. Post hoc analyses revealed that children with Tetralogy of Fallot had significantly higher inattention scores compared with children both with Ventricular Septal Defect (p = 0.043) and controls (p = 0.004). CONCLUSION: Attention-deficit/hyperactivity disorder symptoms and inattention symptoms were significantly more frequent among children aged 10-16 years with CHDs, in particular in children with corrected Tetralogy of Fallot.

HPV-prevalence in elderly women in Denmark.

AIM: In countries like Denmark, cervical cancer incidence is at present relatively high in elderly women, while routine screening stops at age 65 years. On this background, all women aged 69 and above were invited to human papillomavirus (HPV)-screening in Denmark in 2017. METHODS: Women were identified from the Central Population Register and personally invited by digital or ordinary mail to have a screening sample taken by their general practitioner. In four regions, samples were tested for high risk (HPV) with the cobas 4800® HPV-assay, and in the last region with the BD Onclarity® HPV-assay. Participation rate, prevalence of high risk HPV, and proportion of positive samples with HPV16, HPV18, and other high risk HPV-types were tabulated by 5-year age-groups. RESULTS: 455,612 women were invited, and 30.2% (95 confidence interval (CI) 30.0-30.3) participated. Average age of participants was 74.6 years. Overall, 4.3% (95% CI 4.1-4.4) of participants were HPV-positive, of whom 24% had HPV 16/18. HPV-prevalence decreased slightly from 4.5% in women aged 69-73 years to 3.1% in women aged 84-88 years, but was 5.2% in the very small group of participants aged 89+ years. CONCLUSION: Invitation to HPV-screening was well received by elderly women. The HPV-prevalence decreased slightly with increasing age. No rebound of HPV-prevalence after menopause was found when our data were combined with previously published Danish data from younger women. The presently relatively high cervical cancer incidence in elderly women was not reflected in the HPV-prevalence.

Cervical screening in Denmark - a success followed by stagnation.

INTRODUCTION: Despite an intensive screening activity, the incidence of cervical cancer in Denmark has remained stable for the last 15 years, while regional differences have increased. To search for explanations, we investigated possible weaknesses in the screening program. MATERIAL AND METHODS: Data on the screen-targeted women were retrieved from Statistics Denmark. Data on screening activity were retrieved from the annual reports from 2009 to 2015 on quality of cervical screening. Coverage was calculated as proportion of screen-targeted women with at least one cytology sample within recommended time intervals. Insufficient follow-up was calculated as proportion of abnormal and unsatisfactory samples not followed up within recommended time intervals. Diagnostic distribution was calculated for samples with a satisfactory cytology diagnosis. RESULTS: Coverage remained stable at 75%-76% during the study period. Annually, approximately 100,000 women are screened before they are eligible for invitation, and 600,000 invitations and reminders are issued resulting in screening of 200,000 women. In 2009, 21% of abnormal and unsatisfactory samples were not followed up within the recommended time interval; a proportion that had decreased to 15% in 2015. Overall, 11% of satisfactory samples with a cytology diagnosis were abnormal, but with surprising variation from 6% to 15% across regions. DISCUSSION: The success of a screening program depends first of all on coverage and timely follow-up of abnormal findings. Our analysis indicated that the currently high incidence of cervical cancer in Denmark may partly be due to low screening coverage. Also worrisome is a high proportion of non-timely follow-up of abnormal findings. Innovative ways to improve coverage and follow-up are urgently needed.

Early telemedicine training and counselling after hospitalization in patients with severe chronic obstructive pulmonary disease: a feasibility study.

BACKGROUND: An essential element in the treatment of patients with chronic obstructive pulmonary disease (COPD) is rehabilitation, of which supervised training is an important part. However, not all individuals with severe COPD can participate in the rehabilitation provided by hospitals and municipal training centres due to distance to the training venues and transportation difficulties. The aim of the study was to assess the feasibility of an individualized home-based training and counselling programme via video conference to patients with severe COPD after hospitalization including assessment of safety, clinical outcomes, patients' perceptions, organisational aspects and economic aspects. METHODS: The design was a pre- and post-test intervention study. Fifty patients with severe COPD were included. The telemedicine training and counselling included three weekly supervised exercise sessions by a physiotherapist and up to two supervised counselling and training sessions in energy conservation techniques by an occupational therapist. The telemedicine videoconferencing equipment was a computer containing a screen, a microphone, an on/off switch and a volume control. RESULTS: Thirty seven (74%) participants completed the programme, with improvements in health status assessed by the Clinical COPD Questionnaire and physical performance assessed by a sit-to-stand test and a timed-up-and-go test. There were no cases of patient fall or emergency contact with a general practitioner during the telemedicine training sessions. The study participants believed the telemedicine training and counselling was essential for getting started with being physically active in a secure manner. The business case showed that under the current financing system, the reimbursement to the hospital was slightly higher than the hospital expenditures. Thus, the business case for the hospital was positive. The organizational analysis indicated that the perceptions of the staff were that the telemedicine service had improved the continuity of the rehabilitation programme for the patients and enabled the patients' everyday lives to be included in the treatment. CONCLUSIONS: This study showed that home-based supervised training and counselling via video conference is safe and feasible and that telemedicine can help to ensure more equitable access to supervised training in patients with severe COPD. TRIAL REGISTRATION: Clinical Trials NCT02085187 (Date of registration 10.03.2014).

Lessons from CanSpotASF: Moving towards risk-based African Swine Fever surveillance with rule-out testing in Western Canada.

African swine fewer (ASF) is a serious disease present in Africa, Eurasia, and the Caribbean but not in continental North America. CanSpotASF describes the ASF surveillance in Canada as a phased in approach. The first enhancement to the passive surveillance was the risk-based early detection testing (rule-out testing) where eligible cases were tested for ASF virus (ASFv). The objective was to describe how the eligibility criteria were applied to cases in western Canada. In particular, to assess if cases tested for ASFv had eligible conditions and if pathology cases with eligible conditions were tested for ASFv based on the data collated by Canada West Swine Health Intelligence Network (CWSHIN) from British Columbia, Alberta, Saskatchewan, and Manitoba. The study period was August 2020 to December 2022 and the data included two study laboratories. We found that over 90% of cases tested for ASFv had eligible conditions as defined in CanSpotASF. The eligibility criteria were applied at three stages of the disease investigation process: 1) the clinical presentation in the herd; 2) at the initial laboratory assessment; and 3) the final pathology diagnosis. At the two study laboratories the proportion of all submitted cases (culture, serology, PCR, pathology) tested for ASFv was very low 1%. However, in the pathology cases specifically targeted in CanSpotASF, and the proportion of tested cases was 12%. In addition, for eligible pathology cases (eligible diagnosis or test) the proportion tested was higher 15%. These results indicated that CanSpotASF targeted herds with submissions for pathological examination and to some degree eligible conditions which would be herds with health issues (known or unknown). We interpret this as a first step towards risk-based surveillance with health as the defining factor.

Discriminative validity of the Danish version of the Pediatric Evaluation of Disability Inventory (PEDI).

The Pediatric Evaluation of Disability Inventory (PEDI) assesses functional status in children with disabilities aged 0.5-7.5 years. The purpose of this study was to examine if the Danish version of the PEDI was able to discriminate between nondisabled children and children with cerebral palsy (CP) or juvenile idiopathic arthritis (JIA). Convenience sampling was used to select the clinical samples that consisted of 22 children with CP and 14 children with JIA aged 1.5-7.5 years. An additional sample, consisting of 224 nondisabled children aged 1.0-5.9 years, was obtained on the basis of random sampling. The PEDI was administered as a questionnaire completed by the parents. Results from receiver operating characteristics (ROC) analysis showed that in the case of discrimination between children with CP and nondisabled children, the sensitivity and specificity were 77.3 and 97.8%, respectively. In the discrimination between children with JIA and nondisabled children, the sensitivity and specificity were 99.8 and 81.7%, respectively. Study results indicate that the Danish version of the PEDI shows good discriminative validity. Further studies of the discriminative validity are recommended.

Development and evaluation of a new method to combine clinical impression survey data with existing laboratory data for veterinary syndromic surveillance with the Canada West Swine Health Intelligence Network (CWSHIN).

The Canada West Swine Health Intelligence Network (CWSHIN) is a surveillance system imbedded in an intelligence network. It has been conducting syndromic surveillance in the four western provinces of Canada since 2012. The quarterly activities include repeated clinical impression surveys, compilation of laboratory data, discussion of trends with an expert group (practitioners, laboratory diagnosticians) and swine health reports for producers and swine practitioners. However, due to the lack of standardized population identifiers across data sources usual methods of combining data could not be applied and the collated data were not being fully utilized and analysed. Therefore in 2019, CWSHIN underwent a substantial review resulting in the "Next Generation CWSHIN". The objectives of this study were to develop and evaluate a new data merging method to combine CWSHIN's clinical impression survey and laboratory data; and to provide examples of analyses and modeling based on these data. The data for analysis were restricted to repeated clinical impression surveys (2019-2020) from veterinary practitioners and laboratory diagnostic data (2016-2020). Merging surveillance data from existing sources can be challenging. Therefore, as an alternative to merge data using a hierarchy of population identifiers, we developed a Disease Map to link surveillance data from all our data-sources. The resulting Data Repository allowed monitoring of temporal trends of syndromes, clinical diseases, and laboratory identified organisms, but it cannot provide estimates of disease occurrence. Two main reasons were the lack of denominators and using existing data on routine diagnostic tests. Therefore, discussion in the expert group (veterinary practitioners, laboratory diagnosticians, swine health experts) was critical to the system's success. Based on repeated clinical impression surveys a stochastic scenario tree model for freedom from Foot and Mouth Disease (CWSHIN Blister model) was also developed. In conclusion, the method to link existing data systems from multiple divergent sources by means of a Disease Map improved CWSHIN's veterinary syndromic surveillance. Together the Data Repository and Disease map provided flexibility to monitor temporal trends, define populations and diseases, and allow analysis. However, it is critical that the surveillance is coupled with a good intelligence network that can help interpret the results and disseminate knowledge to veterinarians and producers.

Histological outcomes in HPV-screened elderly women in Denmark.

INTRODUCTION: Danish women exit cervical cancer screening at age 65 years, but 23% of cervical cancer cases occur beyond this age. In addition, due to gradual implementation of cervical cancer screening, older women are underscreened by today´s standards. A one-time screening with HPV test was therefore offered to Danish women born before 1948. METHODS: Register based study reporting histology diagnoses and conizations in women found HPV positive in the one-time screening. Number and proportion of women with severe or non-severe histology results were calculated for screened and HPV-positive women by age group or region of residence. Number of women with biopsy and/or conization per case of cervical intraepithelial neoplasia (CIN) grade 2 or worse (CIN2+) or CIN3+ were also calculated by age groups and region. RESULTS: 4,479 (4.1% of screened women) had positive HPV test. 94% of these had one or more additional tests. 2,785 (62%) of HPV-positive women had histology results, and conization was performed in 1,076 (24% of HPV-positive and 1% of all screened women). HPV positivity and CIN3+ detection varied little between regions, but the proportions of HPV positive women undergoing histology varied between regions from 40% to 86% and the proportion with conization from 13% to 36%. Correspondingly, the number of histologies and conizations per CIN3+ detected varied from 5.9 to 11.2 and 1.8 to 4.7, respectively. In total, 514 CIN2+ (0.47% of screened women, 11% of HPV-positive) and 337 CIN3+ (0.31% of screened women, 7.5% of HPV-positive) were diagnosed, including 37 cervical cancer cases. DISCUSSION: HPV screening of insufficiently screened birth cohorts can potentially prevent morbidity and mortality from cervical cancer but longer follow-up is needed to see if cancer incidence declines in the screened women in the coming years. Management strategies differed among regions which influenced the proportions undergoing biopsy/conization.

Applicability and intrarespondent reliability of the pediatric evaluation of disability inventory in a random Danish sample.

PURPOSE: To examine the applicability of US reference data from the Pediatric Evaluation of Disability Inventory (PEDI) in a random Danish sample and to assess intrarespondent reliability. METHODS: The PEDI was administered as a mailed questionnaire that was completed by the parents. Linear regression models and comparisons of item difficulty were performed in the data analysis. Intraclass correlation coefficients were used in the intrarespondent analysis. RESULTS: US and Danish children differed on 3 of the 6 subscales of the PEDI. Danish children had significantly lower scores on the caregiver assistance subscales (self-care and mobility) and significantly higher scores on the functional skills subscale (social function). Item difficulty was found to be comparable (r = 0.82-0.97) on all 6 subscales. Intrarespondent reliability was good (intraclass correlation coefficient = 0.62-0.97). CONCLUSION: The PEDI reference values seem partly applicable in a Danish population. In a Danish rehabilitation setting, interpreting PEDI scores with regard to detecting functional delays must be done cautiously.

A modified TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) applied to choosing appropriate selection methods in ongoing surveillance for Avian Influenza in Canada.

To achieve an appropriate and efficient sample in a surveillance program, the goals of the program should drive a careful consideration of the selection method or combination of selection methods to be applied. Therefore, the ongoing analysis and assessment of a surveillance system may include an assessment of the ability of the applied selection methods to generate an appropriate sample. There may be opinions from many technical experts (TEs) and many criteria to consider in a surveillance system so there is a need for methods to combine knowledge, priorities and preferences from a group of TEs. This paper proposes a modified weighted and unweighted TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) analysis to choose selection methods in surveillance. An example from the Canadian Notifiable Avian Influenza surveillance (CanNAISS) is used to illustrate the method as this surveillance offers unique data with multiple selection methods and subpopulations. The primary objective was to assess the performance of the different selection methods applied in CanNAISS, from 2008 to 2013, in three subpopulations (A-C). A modified TOPSIS (weighted and unweighted) analyses is proposed to aggregate preferences from three TEs and to identify the selection method that was closest to the ideal solution agreed upon by the TEs. Criteria weights were provided individually by three TEs. For the group decision making, internal and external aggregation approaches were used with arithmetic and geometric means. The results of the weighted modified TOPSIS analysis showed that the selection methods that used farm registries yielded high estimates of the relative closeness to ideal-solution. The ranking of selection methods based on the modified TOPSIS weighted analysis, conducted at the individual and group decision making levels were similar. Regardless of the aggregation approach used (internal or external) in group decision making, the use of the arithmetic and geometric means yielded similar estimates of relative closeness to ideal-solution. The unweighted modified TOPSIS analysis yielded similar estimates of the relative closeness to the ideal-solution and therefore making the interpretation of the results difficult. The weighted modified TOPSIS analysis contributed to an informed decision on the best selection method to apply in CanNAISS. The weighted modified TOPSIS analysis is a straightforward and suitable technique to address decision making problems where the profile of the ideal and non-ideal solutions is known a priori by the decision makers.

Description of empirical movement data from Canadian swine herds with an application to a disease spread simulation model.

We report the methods and findings of a survey of Canadian swine producers summarizing farm-types at-risk of foreign animal disease (FAD) and the routine movement of animals, semen and workers among swine farms, as observed during a 42-day period. Of the 311 producers who returned completed questionnaires, 17% represented swine-herds with no swine or semen movement on or off the farm during the 42 days, 57% were sow herds or farrow-to-finish herds with limited movement onto the farm but movement off the farm, and 26% were swine-herds with movements on and off the farm. A substantial number of premises (>50% in some provinces) with swine also kept other animal species on the same premises. We applied the empirical movement data from the survey in a stochastic simulation model to estimate the number of herds infected and the basic regional distribution of infection that could be expected to occur if the FAD was not detected and routine movements were permitted to occur up to 42 days after infection with a FAD of a single randomly selected herd. Forty-five percent of the simulations did not involve spread beyond the index farm, whereas 34.8% involved spread among five or more farms after 42 days of routine movement.

Prevalence of and risk factors for influenza in southern Ontario swine herds in 2001 and 2003.

This research included 2 prevalence studies and a risk-factor investigation conducted in 2001 at 93 sites with sows only, finishers only, or both. In 2001, 1300 serum samples from sows in 65 herds and 720 serum samples from finisher pigs in 72 herds were tested for antibodies to swine influenzavirus (SIV) of H1N1 subtype with an enzyme-linked immunosorbent assay (ELISA). In 2003, 1140 serum samples from sows in 76 herds were tested for antibodies to SIV of H3N2 subtype with a hemagglutination-inhibition assay based on A/Swine/Colorado/1/77 and A/Swine/Texas/4199-2/98 isolates. The apparent pig-level H1N1 seroprevalence in 2001 was 61.1% and 24.3% in sows and finishers, respectively. The apparent pig-level seroprevalence in 2003 for H3N2 A/Sw/CO/1/77 and A/Sw/TX/4199-2/98 in sows was 0.6% and 0.7%, respectively. The factors associated with sow-herd H1N1 positivity included pig or farm density at different geographic levels, an external source of breeding pigs, number of animals on site, and decreasing proximity to other barns. Higher-parity sows had higher odds of seropositivity, but there was significant random variability in this association among herds. The odds of finisher-herd SIV positivity were higher with large herd size, high pig farm density, and farrow-to-finish type of farm. Finisher herds were SIV-positive only if source sow herds were positive. Simultaneously, 45% of finisher herds were SIV-negative although sow source herds were positive.

Pig and herd level prevalence of Toxoplasma gondii in Ontario finisher pigs in 2001, 2003, and 2004.

The objective of this study was to estimate the apparent and true prevalence of exposure to Toxoplasma gondii in Ontario finisher pigs. During the study period (2001 to 2004), sera from 6048 pigs were tested with a commercial enzyme-linked immunosorbent assay (ELISA); 103 farms were included 1 to 3 times in the study. True prevalence was estimated using a Bayesian approach. Apparent prevalence at the pig level was 1.59% [95% confidence interval (CI): 0.45, 2.99] in 2001, 0.06% (95% CI: 0.00, 0.46) in 2003, and 0.26% (95% CI: 0.00, 0.82) in 2004. Apparent prevalence at the herd-level was 13.7% (95% CI: 7.5, 22.3) in 2001; 1.25% (95% CI: 0.03, 6.77) in 2003, and 3.75% (95% CI: 0.78, 10.6) in 2004. Similarly, posterior Bayesian estimates of true prevalence at the pig level were 1.7% [95% probability interval (PI): 1.2, 2.2] in 2001, 0.2% (95% PI: 0.04, 0.4) in 2003, and 0.3% (95% PI: 0.1, 0.7) in 2004. At the herd level, posterior estimates of prevalence were 11.6% (95% PI: 7.4, 16.8) in 2001, 0% (95% PI: 0.0, 2.5) in 2003, and 1.2% (95% PI: 0.0, 5.0) in 2004 when a herd cut-point > or = 1 was used. Exposure to T. gondii in finishing pig farms in Ontario appears to be infrequent.

Danish method study on cervical screening in women offered HPV vaccination as girls (Trial23): a study protocol.

INTRODUCTION: The first birth cohorts of women offered human papillomavirus (HPV) vaccination as girls are now entering cervical screening. However, there is no international consensus on how to screen HPV vaccinated women. These women are better protected against cervical cancer and could therefore be offered less intensive screening. Primary HPV testing is more sensitive than cytology, allowing for a longer screening interval. The aim of Trial23 is to investigate if primary HPV testing with cytology triage of HPV positive samples is a reasonable screening scheme for women offered HPV vaccination as girls. METHODS: Trial23 is a method study embedded in the existing cervical screening programme in four out of five Danish regions. Without affecting the screening programme, women born in 1994 are randomised to present screening with liquid-based cytology every third year (present programme arm) or present screening plus an HPV test (HPV arm). The study started 1 February 2017 and will run over three screening rounds corresponding to 7-8 years. ANALYSES: The primary endpoint is cervical intraepithelial neoplasia grade 3 or above. The trial is undertaken as a non-inferiority study including intention-to-treat and per-protocol analyses. The potential effect of primary HPV screening with a 6-year interval will be calculated from the observed data. ETHICS AND DISSEMINATION: The study protocol has been submitted to the ethical committee and deemed a method study. All women are screened according to routine guidelines. The study will contribute new evidence on the future screening of HPV vaccinated birth cohorts of women. All results will be published in open-access journal. TRIAL REGISTRATION: NCT03049553; Pre-results.

Spatial clustering of swine influenza in Ontario on the basis of herd-level disease status with different misclassification errors.

This approach maximizes sensitivity of serology-based monitoring systems by considering spatial clustering of herds classified as false positive by herd testing, allowing outbreaks to be detected in an early phase. The primary objective of this study was to determine whether swine herds infected with influenza viruses cluster in space, and if so, where they cluster. The secondary objective was to investigate the combining of a multivariate spatial scan statistic with herd test results to maximize the sensitivity of the surveillance system for swine influenza. We tested for spatial clustering of swine influenza using the Cuzick-Edwards test as a global test. The location of the most likely spatial clusters of cases for each subtype and strain in a sample of 65 sow and 72 finisher herds in 2001 (Ontario, Canada), and 76 sow herds in 2003 (Ontario, Canada) was determined by a spatial scan statistic in a purely spatial Bernoulli model based on single and multiple datasets. A case herd was defined by true herd-disease status for sow or finisher herds tested for H1N1, and by apparent herd-disease status for sow herds tested for two H3N2 strains (A/Swine/Colorado/1/77 (Sw/Col/77) and A/Swine/Texas/4199-2/98 (Sw/Tex/98)). In sow herds, there was no statistically significant clustering of H1N1 influenza after adjustment for pig-farm density. Similarly, spatial clustering was not found in finisher herds. In contrast, clustering of H3N2 Sw/Col/77 (prevalence ratio=12.5) and H3N2 Sw/Tex/98 (prevalence ratio=15) was identified in an area close to a region with documented isolation of avian influenza isolates from pigs. For the H1N1 subtype tested by ELISA, we used an approach that minimized overall misclassification at the herd level. This could be more applicable for detecting clusters of positive farms when herd prevalence is moderate to high than when herd prevalence is low. For the H3N2 strains we used an approach that maximized herd-level sensitivity by minimizing the herd cut-off. This is useful in situations where prevalence of the pathogen is low. The results of applying a multivariate spatial scan statistic approach, led us to generate the hypothesis that an unknown variant of influenza of avian origin was circulating in swine herds close to an area where avian strains had previously been isolated from swine. Maximizing herd sensitivity and linking it with the spatial information can be of use for monitoring of pathogens that exhibit the potential for rapid antigenic change, which, consequently, might then lead to diminished cross-reactivity of routinely used assays and lower test sensitivity for the newly emerged variants. Veterinary authorities might incorporate this approach into animal disease surveillance programs that either substantiate freedom from disease, or are aimed at detecting early incursion of a pathogen, such as influenza virus, or both.

Scenario tree model for animal disease freedom framed in the OIE context using the example of a generic swine model for Aujeszky's disease in commercial swine in Canada.

"Freedom from animal disease" is an ambiguous concept that may have a different meaning in trade and science. For trade alone, there are different levels of freedom from OIE listed diseases. A country can: be recognized by OIE to be "officially free"; self-declare freedom, with no official recognition by the OIE; or report animal disease as absent (no occurrence) in six-monthly reports. In science, we apply scenario tree models to calculate the probability of a population being free from disease at a given prevalence to provide evidence of freedom from animal disease. Here, we link science with application by describing how a scenario tree model may contribute to a country's claim of freedom from animal disease. We combine the idea of a standardized presentation of scenario tree models for disease freedom and having a similar model for two different animal diseases to suggest that a simple generic model may help veterinary authorities to build and evaluate scenario tree models for disease freedom. Here, we aim to develop a generic scenario tree model for disease freedom that is: animal species specific, population specific, and has a simple structure. The specific objectives were: to explore the levels of freedom described in the OIE Terrestrial Animal Health Code; to describe how scenario tree models may contribute to a country's claim of freedom from animal disease; and to present a generic swine scenario tree model for disease freedom in Canada's domestic (commercial) swine applied to Aujeszky's disease (AD). In particular, to explore how historical survey data, and data mining may affect the probability of freedom and to explore different sampling strategies. Finally, to frame the generic scenario tree model in the context of Canada's claim of freedom from AD. We found that scenario tree models are useful to support a country's claim of freedom either as "recognized officially free" or as part of a self-declaration but the models should not stand alone in a claim. The generic AD scenario tree model demonstrated the benefit of combining three sources of surveillance data and helped to design the surveillance for the next year. The generic AD scenario model is one piece in Canada's self-declaration of freedom from AD. The model is strongly supported by the fact that AD has never been detected in Canada.