Exploring herd-level perinatal calf mortality risk factors in eastern Canadian dairy farms

This closed cohort study aimed to identify the associations between dairy calf management practices and herd-level perinatal calf mortality risk. From February 2020 to June 2021, predominantly Holstein dairy farms in Québec (n = 1,832) and New Brunswick (n = 52), Canada, that were registered in the dairy herd improvement program were visited once. A questionnaire covering all aspects of precalving, calving, and colostrum management was administered. Data regarding perinatal mortality were retrieved from the dairy herd improvement program database for each farm for 2021. Perinatal mortality was calculated for each farm as the proportion of calves dead at birth or dying within 24 h after birth. A multivariable negative binomial model was used to assess herd-level factors associated with the risk of perinatal mortality. The final model included the lying surface in the calving area, the typical time to first colostrum intake, typical cow-calf contact time, the proportion of males born, the proportion of assisted calvings, and herd size. Herd-level perinatal mortality risk ranged from 0% to 38.1% (mean ± SE = 7.6% ± 0.1%). A greater proportion of males born, a higher proportion of assisted calvings, and delayed colostrum feeding were associated with increased herd-level perinatal mortality. Factors associated with a decreased herd-level perinatal mortality risk were having a typical cow-calf contact time between 7 and 12 h after calving compared with reduced cow-calf contact time, soft lying surfaces in the calving area compared with concrete and mat-lying surfaces, and an increased number of calvings per year. Our results show that although some of the significant risk factors are not well understood (i.e., calving area lying surface, typical cow-calf contact time), Canadian farmers could focus on the factors under their control (i.e., time to first colostrum feeding, proportion of difficult calvings, males born, and calvings per year) to reduce the risk of perinatal mortality. Future work should focus on qualitative research to understand the dairy farmer motivations and limitations to implementing practices identified in this and other studies to reduce perinatal mortality.

Unequal access to opioid agonist treatment and sterile injecting equipment among hospitalized patients with injection drug use-associated infective endocarditis

BACKGROUND

Addiction treatment and harm reduction services reduce risks of death and re-infection among patients with injection drug use-associated infective endocarditis (IDU-IE), but these are not offered at many hospitals. Among hospitalized patients with IDU-IE at the two tertiary-care hospitals in the Canadian Maritimes, we aimed to identify (1) the availability of opioid agonist treatment (OAT) and sterile drug injecting equipment, and (2) indicators of potential unmet addiction care needs.

METHODS

Retrospective review of IDU-IE hospitalizations at Queen Elizabeth II Health Sciences Centre (Halifax, Nova Scotia) and the Saint John Regional Hospital (Saint John, New Brunswick), October 2015 -March 2017. In Halifax, there are no addiction medicine providers on staff; in Saint John, infectious diseases physicians also practice addiction medicine. Inclusion criteria were: (1) probable or definite IE as defined by the modified Duke criteria; and (2) injection drug use within the prior 3 months.

RESULTS

We identified 38 hospitalizations (21 in Halifax and 17 in Saint John), for 30 unique patients. Among patients with IDU-IE and untreated opioid use disorder, OAT was offered to 36% (5/14) of patients in Halifax and 100% (6/6) of patients in Saint John. Once it was offered, most patients at both sites initiated OAT and planned to continue it after discharge. In Halifax, no patients were offered sterile injecting equipment, and during five hospitalizations staff confiscated patients' own equipment. In Saint John, four patients were offered (and one was provided) injecting equipment in hospital, and during two hospitalizations staff confiscated patients' own equipment. Concerns regarding undertreated pain or opioid withdrawal were documented during 66% (25/38) of hospitalizations, and in-hospital illicit or non-medical drug use during 32% (12/38). Two patients at each site (11%; 4/38) had self-directed discharges against medical advice.

CONCLUSIONS

Patients with IDU-IE in the Canadian Maritimes have unequal access to evidence-based addiction care depending on where they are hospitalized, which differs from the community-based standard of care. Indicators of potential unmet addiction care needs in hospital were common.

Estimating the dispersal of Lepeophtheirus salmonis sea lice within and among Atlantic salmon sites of the Bay of Fundy, New Brunswick

The objective of this study was to estimate the impact of infestation pressures on the abundance of the parasitic sea louse, Lepeophtheirus salmonis, in the Bay of Fundy, New Brunswick (NB), Canada, using the Fish-iTrends database for the years 2009-2018. Infestation pressures were calculated as time-lagged weighted averages of the abundance of adult female (AF) sea lice within a site (internal infestation pressure: IIP) and among sites (external infestation pressure: EIP). The EIP weights were calculated from seaway distances among sites and a Gaussian kernel density for bandwidths of 5 to 60 km. The EIP with a bandwidth of 10 km had the best fit, as determined with Akaike's information criterion, and historical AF sea lice abundance. This estimated dispersal distance of 10 km was similar to previous studies in Norway, Scotland and in New Brunswick. The infestation pressures estimated from empirical AF sea lice abundance within and among sites significantly increased the abundance of AF sea lice (p < .001). This study concludes that sea lice burdens within Atlantic salmon farms in the Bay of Fundy, NB, are affected by within site management and could be improved by synchronizing treatments between sites.

Changes to telehealth practices in primary care in New Brunswick (Canada): A comparative study pre and during the COVID-19 pandemic

BACKGROUND

During the COVID-19 pandemic, telehealth technologies were used in the primary health care setting in New Brunswick as a means to continue providing care to patients while following public health guidelines. This study aimed to measure these changes and examine if they improved timely access to primary care. A secondary goal was to identify which telehealth technologies were deemed sustainable by primary care providers.

METHODS

This was a comparative study on the use of telehealth technology before and during the COVID-19 pandemic. Between April 2020 and November 2020, 114 active primary care providers (family physicians or nurse practitioners) responded to the online survey.

RESULTS

The findings illustrated an increase in the use of telehealth technologies. The use of phone consultations increased by 122%, from 43.9% pre-pandemic to 97.6% during the pandemic (p < 0.001). The use of virtual consultation (19.3% pre-pandemic vs. 41.2% during the pandemic, p < 0.001), emails and texts also increased during the pandemic. Whereas the more structural organizational tools (electronic medical charts and reservation systems) remained stable. However, those changes did not coincide with a significant improvement to timely access to care during the pandemic. Many participants (40.1%) wanted to keep phone consultations, and 21.9% of participants wanted to keep virtual consultations as part of their long-term practice.

INTERPRETATION

The observed increase in the use of telehealth technologies may be sustainable, but it has not significantly improved timely access to primary care in New Brunswick.

Prevalence and Intensity of Salmincola edwardsii in Brook Trout in Northwest New Brunswick, Canada

Parasites can compromise the health and fitness of individual fish, and it is important to generate baseline information that can then be used to document changes in the abundance and distribution of potentially pathogenic parasites. The ectoparasitic copepod Salmincola edwardsii was assessed with respect to prevalence (percentage of infected fish per site), infection intensity (number of parasites per infected fish), and attachment location on Brook Trout Salvelinus fontinalis in northwest New Brunswick, Canada. Ten sample sites were assessed, with six sites on two streams in the Quisibis River basin and four sites on three streams in the Restigouche River basin. Parasite species identity was supported by 100% sequence identity with S. edwardsii in a variable region within 28S rDNA. The prevalence of fish infected per site ranged from 19.0% to 79.6%, with an overall prevalence of 48.5 ± 19.1% (mean ± SD) per site. Mean infection intensity was 1.5 ± 0.9 copepods/fish (range = 1-7), with parasites almost exclusively surrounding the dorsal fin and/or adipose fin (97.6%). There was no influence of trout age-class on parasite prevalence. Some fish presented with fin erosion at the site of parasite attachment (12.5%), and 6.2% also presented with hyperplastic skin lesions where no parasites were observed, that could be misinterpreted as secondary bacterial or fungal infections. Skin and fin damage were significantly more common when fish were infected with three or more individual parasites. The pathogenic potential of this parasite makes its presence noteworthy as a risk to salmonids that are both recreationally and ecologically important.

A Multiple Streams Approach to Understanding the Issues and Challenges of Lyme Disease Management in Canada's Maritime Provinces

This study examines potential challenges facing Lyme disease patients in Canada’s Maritime provinces—New Brunswick, Nova Scotia, Prince Edward Island—and considers how issues could be addressed. Reviews of both the academic and grey literature are complemented by surveys targeting both medical professionals and decision makers in government. Combined, the literature reviews and surveys demonstrate that there is considerable debate surrounding the effectiveness of testing, treatment options, and the existence of chronic Lyme disease. As the focus on the Maritimes demonstrates, these debates often pit the medical community against patients and patient advocates and, thus far, governments have been unable to produce policy that entirely pleases either side. Moving forward, this study recommends the creation of a discussion forum via a federal Commission of inquiry to review best practise guidelines for Lyme disease. The key is to foster an unbiased probe of central issues surrounding treatment and diagnosis without alienating stakeholders. This course of action will not necessarily solve the issue of Lyme disease, but would foster a greater understanding through dialogue that includes and validates the experiences of stakeholders, which is something that is currently missing.

Case definition for clinical and subclinical bacterial kidney disease (BKD) in Atlantic Salmon (Salmo salar L.) in New Brunswick, Canada

Bacterial kidney disease (BKD) is considered an important cause of loss in salmon aquaculture in Atlantic Canada. Causative agent of BKD is the Gram-positive bacteria Renibacterium salmoninarum. Infected salmon are often asymptomatic (subclinical infection), and the disease is considered chronic. One of the challenges in quantifying information from farm production and health records is the application of a standardized case definition. Case definitions for farm-level and cage-level clinical and subclinical BKD were developed using retrospective longitudinal data from aquaculture practices in New Brunswick, Canada, combining (i) industry records of weekly production data including mortalities, (ii) field observations for BKD using reports of veterinarians and/or fish health technicians, (iii) diagnostic submissions and test results and (iv) treatments used to control BKD. Case definitions were evaluated using veterinarians' expert judgements as reference standard. Eighty-nine and 66% of sites and fish groups, respectively, were associated with BKD at least once. For BKD present (subclinical or clinical), sensitivity and specificity of the case definition were 75-100% varying between event, fish group, site cycle and level (site pen). For clinical BKD, sensitivities were 29-64% and specificities 91-100%. Industry data can be used to develop sensitive case definitions.

Effect of timing of count events on estimates of sea lice abundance and interpretation of effectiveness following bath treatments

Effectiveness of sea lice bath treatment is often assessed by comparing pre- and post-treatment counts. However, in practice, the post-treatment counting window varies from the day of treatment to several days after treatment. In this study, we assess the effect of post-treatment lag time on sea lice abundance estimates after chemical bath treatment using data from the sea lice data management program (Fish-iTrends) between 2010 and 2014. Data on two life stages, (i) adult female (AF) and (ii) pre-adult and adult male (PAAM), were aggregated at the cage level and log-transformed. Average sea lice counts by post-treatment lag time were computed for AF and PAAM and compared relative to treatment day, using linear mixed models. There were 720 observations (treatment events) that uniquely matched pre- and post-treatment counts from 53 farms. Lag time had a significant effect on the estimated sea lice abundance, which was influenced by season and pre-treatment sea lice levels. During summer, sea lice were at a minimum when counted 1 day post-treatment irrespective of pre-treatment sea lice levels, whereas in the spring and autumn, low levels were observed for PAAM over a longer interval of time, provided the pre-treatment sea lice levels were >5-10.

Incidence of Nonmelanoma Skin Cancer in New Brunswick, Canada, 1992 to 2001

Background:

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), collectively referred to as nonmelanoma skin cancer (NMSC), cause significant morbidity and generate a substantial cost to the health care system. Canadian data on the incidence of NMSC are lacking.

Objective:

To study the incidence and characteristics of NMSC in New Brunswick, Canada (population 729,498 people in 2001), by using the Provincial Cancer Registry.

Method:

Data were obtained from 1992 to 2001 from the New Brunswick Provincial Cancer Registry, to which reporting of all cancers is mandatory. Multiple tumors of a given histologic type are recorded only once in the registry per individual per lifetime. A descriptive analysis of incidence rates of BCC and invasive SCC of the skin was performed in relation to gender, age, and anatomic location. The main outcome measures were the age- and sex-specific incidence rates of BCC and SCC. Age standardization was performed using the Canadian, US, and world standard populations.

Results:

When adjusted to the world standard population, the age-standardized incidence rates (ASIRs) per 100,000 population for BCC from 1992 through 2001 were 87 for males and 68 for females. For invasive SCC, the ASIRs per 100,000 population were 34 for males and 16 for females. There was an increasing incidence trend for both BCC and invasive SCC over the 10-year study period, with minimal change in the incidence of SCC in women. The overall ratio of BCC to invasive SCC in the population was 2.8 to 1. The approximate lifetime probabilities of developing BCC and invasive SCC were 13% and 5%, respectively.

Conclusions:

The incidence of NMSC in the province of New Brunswick is similar to that reported from 1973 through 1987 in the province of British Columbia, higher than those reported in most parts of Europe, and lower than all published rates in the United States and Australia. Owing to the inability of the registry to account for tumor multiplicity, the actual annual number of all NMSC lesions in this population is likely much higher.

Lyme disease risk in dogs in New Brunswick

This study assessed the seroprevalence of anti-Borrelia burgdorferi antibodies in New Brunswick dogs. Testing of 699 serum samples from dogs across the province revealed a 6% province-wide seropositivity, more than 6 times higher than that found in 2008. The rapid increase in seropositivity indicates increased Lyme disease risk to both canine and human health.

Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.

Emergency department use: is frequent use associated with a lack of primary care provider?

OBJECTIVE

To determine if having a primary care provider is an important factor in frequency of emergency department (ED) use.

DESIGN

Analysis of a central computerized health network database.

SETTING

Three EDs in southern New Brunswick.

PARTICIPANTS

All ED visits during 1 calendar year to an urban regional hospital (URH), an urban urgent care centre (UCC), and a rural community hospital (RCH) were captured.

MAIN OUTCOME MEASURES

Patients with and without listed primary care providers were compared in terms of number of visits to the ED. A logistic regression analysis was used to determine factors predictive of frequent attendance.

RESULTS

In total, 48 505, 41 004, and 27 900 visits were made to the URH, UCC, and RCH, respectively, in 2009. The proportion of patients with listed primary care providers was 36.6% for the URH, 37.1% for the UCC, and 89.4% for the RCH. Among ED patients at all sites, frequent attenders (4 or more visits to an ED in 1 year) were significantly more likely (59.6% vs 45.1%, P < .001) to have listed primary care providers. Other factors that predicted frequent use included attendance at a rural ED, female sex, and older age.

CONCLUSION

This study characterizes attendance rates for 3 EDs in southern New Brunswick. Our findings highlight interesting differences between urban and rural ED populations, and suggest that frequent use of the ED might not be related to lack of a listed primary care provider.

The effect of a smoking ban on hospitalization rates for cardiovascular and respiratory conditions in Prince Edward Island, Canada

Background

This is the first study to have examined the effect of smoking bans on hospitalizations in the Atlantic Canadian socio-economic, cultural and climatic context. On June 1, 2003 Prince Edward Island (PEI) enacted a province-wide smoking ban in public places and workplaces. Changes in hospital admission rates for cardiovascular (acute myocardial infarction, angina, and stroke) and respiratory (chronic obstructive pulmonary disease and asthma) conditions were examined before and after the smoking ban.

Methods

Crude annual and monthly admission rates for the above conditions were calculated from April 1, 1995 to December 31, 2008 in all PEI acute care hospitals. Autoregressive Integrated Moving Average time series models were used to test for changes in mean and trend of monthly admission rates for study conditions, control conditions and a control province after the comprehensive smoking ban. Age- and sex-based analyses were completed.

Results

The mean rate of acute myocardial infarctions was reduced by 5.92 cases per 100,000 person-months (P = 0.04) immediately after the smoking ban. The trend of monthly angina admissions in men was reduced by −0.44 cases per 100,000 person-months (P = 0.01) in the 67 months after the smoking ban. All other cardiovascular and respiratory admission changes were non-significant.

Conclusions

A comprehensive smoking ban in PEI reduced the overall mean number of acute myocardial infarction admissions and the trend of angina hospital admissions.

Increased reactions to pediatric influenza vaccination following concomitant pneumococcal vaccination

BACKGROUND

Influenza in children causes significant morbidity and hospitalizations and also some mortality particularly in children < 5 years of age. Influenza vaccination in children has been shown to be safe and effective, but in 2010 the pediatric influenza vaccination program was suspended in Western Australia after the rate of febrile convulsions observed (9/1000 doses) was 55 times the previously reported rate. In 2009, over 80% of all children in New Brunswick were vaccinated with an adjuvanted monovalent H1N1 vaccine shown to have very high effectiveness, raising the prospect of potential hyper-responsiveness because of residual protection. We conducted enhanced post-marketing surveillance to monitor local and general reactions.

METHODS

Parents of participating children seen at dedicated vaccination clinics were given influenza vaccine survey kits to record local and general symptoms up to 3 days following receipt of season influenza vaccine.

RESULTS

Febrile reactions of ≥ 38° occurred in <10% of children who received a first dose of seasonal influenza vaccine (n = 660) and severe febrile incidents with fever ≥ 39° were uncommon. Concurrent administration of other vaccine(s) including conjugated pneumococcal vaccine appeared to increase reactogenicity. No child in the study had a febrile convulsion.

CONCLUSION

  Influenza vaccines in children are safe, and this study provides a baseline for rapid assessment studies at the start of a vaccine season. Parents should be aware of increased fevers with concurrent vaccine administration, and antipyretics should be considered.

Identifying at-risk communities for action on cancer prevention: a case study in new brunswick (Canada) communities

Health statistics reported by large geographic area such as province, state, county or health region offer little insight into disease conditions at the community level where people live and work, where occupational and environmental exposures occur, and where industrial emissions are often concentrated. This study investigated overall patterns of cancer incidence and socioeconomic status (SES) among 14 communities in the province of New Brunswick (Canada). A multivariate ordination technique, hierarchical clustering, and permutation procedures were used to identify and test significance of community clusters and whether the overall pattern of SES was correlated with patterns of cancer among communities. Communities with significantly high or significantly low overall rates of cancers were identified, patterns that were not related to SES. The potential influence of age, small populations, diagnostic screening, smoking and environmental risk factors contributing to locally elevated cancer rates are discussed. Cancer incidence reported at smaller spatial scales provides health officials and researchers with a basis for identifying communities potentially at-risk and aids in the development of appropriate community-based risk reduction actions and cancer prevention.

Infections with Philometra sp. associated with mortalities in wild-hatched captive-raised striped bass, Morone saxatilis (Walbaum)

The striped bass, Morone saxatilis (Walbaum), once represented an important resource for fisheries in the St Lawrence River (Quebec, Canada). A restoration programme, involving captive propagation, was implemented with the objective of restocking the population, which had disappeared in the late 1960s. An unusually high rate of mortality was observed during the winter of 2006 in captive-raised fingerlings that were originally collected from the Miramichi River (New Brunswick, Canada) the previous summer. Post-mortem examinations revealed extensive granulomatous and hyperplastic peritonitis associated with numerous nematodes of the genus Philometra. Given the severity of the lesions, high intensity of infection by Philometra sp. was presumed to be the primary factor in the unusual mortalities reported that winter. Observations suggest that this nematode, which was acquired in the wild, cannot establish itself in a captive environment, most likely because of the absence of the obligate intermediate host. Examination of archived specimens of striped bass showed that this parasite was probably present in the St Lawrence River population prior to its extirpation. Consequently, the introduction of infected fish into this ecosystem should not be a concern. Nevertheless, infection-related mortalities of fingerlings might affect dynamics of wild striped bass populations.

Cancer prevalence and education by cancer site: logistic regression analysis

BACKGROUND

Previously, using the American National Health Interview Survey (NHIS) and a logistic regression analysis, we found that upper aerodigestive tract (UADT) cancer is correlated with low socioeconomic status (SES). The objective of this study was to determine if this correlation between low SES and cancer prevalence exists for other cancers.

METHODS

We again used the NHIS and employed education level as our main measure of SES. We controlled for potentially confounding factors, including smoking status and alcohol consumption.

RESULTS

We found that only two cancer subsites shared the pattern of increased prevalence with low education level and decreased prevalence with high education level: UADT cancer and cervical cancer.

CONCLUSIONS

UADT cancer and cervical cancer were the only two cancers identified that had a link between prevalence and lower education level. This raises the possibility that an associated risk factor for the two cancers is causing the relationship between lower education level and prevalence.

Disrespect, harassment, and abuse: all in a day's work for family physicians

OBJECTIVE

To examine harassment and abusive encounters between family physicians and their patients or colleagues in the workplace.

DESIGN

Qualitative case study using semistructured interviews.

SETTING

Province of New Brunswick.

PARTICIPANTS

Forty-eight family physicians from across the province.

METHODS

A collective case-study approach was developed, with 24 cases of 2 individuals per case. Cases were selected based on sex, location (urban or rural), language (French or English), and number of years since medical school graduation (< 10 years, 10 to 20 years, or > 20 years). Physicians were interviewed in either French or English. Participants were recruited using the College of Physicians and Surgeons of New Brunswick's physician directory. Based on the rates of response and participation, some cases were overrepresented, while others were not completed. All interviews were audiotaped, transcribed verbatim, and analyzed thematically using a categorical aggregation approach. A coding scheme for the thematic analysis was developed by the research team before the interviews were transcribed.

MAIN FINDINGS

Although the original intent of this study was to examine the work environment of family physicians in light of the increasing number of women entering the profession, harassment and abusive encounters in the workplace emerged as a main theme. These encounters ranged from minor to severe. Minor abusive encounters included disrespectful behaviour and verbal threats by patients, their families, and occasionally colleagues. More severe forms of harassment involved physical threats, physical encounters, and stalking. Demanding patients, such as heavy drug users, were often seen as threatening. Location of practice, years in practice, and sex of the physician seemed to affect abusive encounters--young, female, rural physicians appeared to experience such encounters most often.

CONCLUSION

Abusive encounters in the workplace are concerning. It is essential to address these issues of workplace harassment and abuse in order to protect physician safety and avoid workplace dissatisfaction. Abusive encounters might push family physicians to leave clinical practice prematurely or refuse to work in higher-risk environments, such as emergency departments or rural areas.

Crossing boundaries: family physicians' struggles to protect their private lives

OBJECTIVE

To explore the tensions between professional and personal boundaries and how they affect the work and private lives of family physicians.

DESIGN

Qualitative case study using semistructured interviews.

SETTING

Province of New Brunswick.

PARTICIPANTS

Forty-eight family physicians from across the province.

METHODS

A collective case-study approach was developed, with 24 cases of 2 individuals per case. Cases were selected based on sex, location (urban or rural), language (French or English), and number of years since medical school graduation (< 10 years, 10 to 20 years, or > 20 years). Physicians were interviewed in either French or English. Participants were recruited using the College of Physicians and Surgeons of New Brunswick's physician directory. Based on the rates of response and participation, some cases were overrepresented, while others were not completed. All interviews were audiotaped, transcribed verbatim, and analyzed thematically using a categorical aggregation approach. A coding scheme for the thematic analysis was developed by the research team before the interviews were transcribed.

MAIN FINDINGS

Almost all of the family physicians interviewed discussed how their profession negatively affected their personal lives. Many struggled with issues such as heavy workloads, the adverse effects of their profession on their family lives, and the trespassing of patients onto their personal lives in small towns and rural communities. Some physicians had developed strategies to balance their personal lives with their professional demands; however, this often meant reducing work hours or terminating certain shifts, such as those in the emergency department or after-hours clinics.

CONCLUSION

Family physicians struggle to keep their profession from intruding too much into their private lives. These struggles are important to acknowledge and address in order to avoid physician burnout and premature retirement from clinical practice.

Towards Web-based representation and processing of health information

BACKGROUND

There is great concern within health surveillance, on how to grapple with environmental degradation, rapid urbanization, population mobility and growth. The Internet has emerged as an efficient way to share health information, enabling users to access and understand data at their fingertips. Increasingly complex problems in the health field require increasingly sophisticated computer software, distributed computing power, and standardized data sharing. To address this need, Web-based mapping is now emerging as an important tool to enable health practitioners, policy makers, and the public to understand spatial health risks, population health trends and vulnerabilities. Today several web-based health applications generate dynamic maps; however, for people to fully interpret the maps they need data source description and the method used in the data analysis or statistical modeling. For the representation of health information through Web-mapping applications, there still lacks a standard format to accommodate all fixed (such as location) and variable (such as age, gender, health outcome, etc) indicators in the representation of health information. Furthermore, net-centric computing has not been adequately applied to support flexible health data processing and mapping online.

RESULTS

The authors of this study designed a HEalth Representation XML (HERXML) schema that consists of the semantic (e.g., health activity description, the data sources description, the statistical methodology used for analysis), geometric, and cartographical representations of health data. A case study has been carried on the development of web application and services within the Canadian Geospatial Data Infrastructure (CGDI) framework for community health programs of the New Brunswick Lung Association. This study facilitated the online processing, mapping and sharing of health information, with the use of HERXML and Open Geospatial Consortium (OGC) services. It brought a new solution in better health data representation and initial exploration of the Web-based processing of health information.

CONCLUSION

The designed HERXML has been proven to be an appropriate solution in supporting the Web representation of health information. It can be used by health practitioners, policy makers, and the public in disease etiology, health planning, health resource management, health promotion and health education. The utilization of Web-based processing services in this study provides a flexible way for users to select and use certain processing functions for health data processing and mapping via the Web. This research provides easy access to geospatial and health data in understanding the trends of diseases, and promotes the growth and enrichment of the CGDI in the public health sector.

Histoplasmosis in a dog from New Brunswick

A young dog was presented with a history of chronic diarrhea, anorexia, and weight loss. Histoplasma capsulatum was suspected, based on cytologic examination of lymph node aspirates and peritoneal fluid, and confirmed by fungal culture. To our knowledge, this is the first case of histoplasmosis diagnosed in a dog in Atlantic Canada.

Effect of joystick stiffness, movement speed and movement direction on joystick and upper limb kinematics when using hydraulic-actuation joystick controls in heavy vehicles

Despite the widespread use of hydraulic-actuation joysticks in mobile North American construction, mining and forestry vehicles, the biomechanical effects that joysticks have on their human operators has not been studied extensively. Using nine unskilled joystick operators and a laboratory mock-up with a commonly used North American heavy off-road equipment hydraulic-actuation joystick and operator seat, the purpose of this work was to quantify and compare the effects of three hydraulic-actuation joystick stiffnesses and two movement speeds on upper limb and joystick kinematics as one of the initial steps towards the development of a hydraulic-actuation joystick design protocol. In addition to providing a detailed description of the kinematics of a constrained occupational task, coupled with the corresponding effects of the task on operator upper limb kinematics, results from principal component analysis and ANOVA procedures revealed a number of differences in joystick and upper limb angle ranges and movement curve shapes resulting from the various joystick stiffness-speed combinations tested. For the most part, these joystick motion alterations were caused by small, insignificant changes in one or more upper limb joint angles. The two exceptions occurred for forward movements of the joystick; the fast speed - light stiffness condition movement pattern shape change was caused primarily by an alteration of the elbow flexion-extension movement pattern. Similarly, the fast speed - normal stiffness condition movement curve shape perturbation - was caused principally by a combination of significant movement curve shape alterations to elbow flexion-extension, external-internal shoulder rotation and flexion-extension of the shoulder. The finding that joystick stiffness and speed alterations affect joystick and upper limb kinematics minimally indicates that the joystick design approach of modelling the joystick and operator upper limb as a closed linkage system should be pursued. This approach would allow one to simulate the upper limb and joystick kinematics that result from virtual changes to upper limb and joystick lengths.

Hydrographics and the timing of infectious salmon anemia outbreaks among Atlantic salmon (Salmo salar L.) farms in the Quoddy region of Maine, USA and New Brunswick, Canada

Infectious salmon anemia (ISA) has caused severe morbidity and mortality in farmed Atlantic salmon in North America, Norway, Scotland and the Faroe Islands. The Quoddy region of Maine, United States of America (USA), and New Brunswick (NB), Canada is characterized by extensive tidal mixing and close proximity between farms. This region is also prone to recurrent appearances of ISA, though control measures limit disease spread and severity on infected farms. We conducted a retrospective longitudinal analysis of the apparent impact of hydrographics on the incidence and timing of ISA outbreaks on Atlantic salmon (Salmo salar L.) farms in the Quoddy region from May 2002 to August 2004. A time-series cross-sectional regression of 32 farms over 28 months demonstrated a limited, but statistically significant, spatio-temporal clustering of ISA outbreaks linked hydrographically. New outbreaks correlated temporally with those occurring on-site 1 and 3 months prior, and those occurring within one tidal-excursion upstream the same month. Other risk factors included holdover of previous year-class fish, wharf sharing, and possibly harvests of cages infected in previous months. Conclusions suggest that tidal dispersion does play a role in ISAV transmission in the Quoddy region. Dispersal of free virus and/or tidal distribution of lice or other hydrographically influenced vectors or fomites could all contribute to the spatio-temporal patterns described.

Hereditary ataxia, spastic paraparesis and neuropathy in the French-Canadian population

Historical events have shaped the various regional gene pools of the French-Canadian (FC) population, leading to increased prevalence of some rare diseases. The first studies of these founder effects were performed in large part by astute clinicians such as André Barbeau. In collaboration with others, he contributed greatly to the delineation of phenotypic subtypes of these conditions. As such, the following neurogenetic disorders were first identified in patients of FC origin: AOA2, ARSACS, HSAN2, RAB, and HMSN/ACC. We have summarized our current knowledge of the main hereditary ataxias, spastic parapareses and neuropathies that are particular to the FC population. The initial genetic characterization of the more common and homogeneous of these diseases has been largely completed. We predict that the regional populations of Canada will allow the identification of new rare forms of hereditary ataxias, spastic parapareses and neuropathies, and contribute to the unravelling of the genetic basis of these entities.

Suicide cases in New Brunswick from April 2002 to May 2003: the importance of better recognizing substance and mood disorder comorbidity

OBJECTIVE

To investigate all suicide cases that occurred in New Brunswick in the 14 months spanning April 1, 2002, to May 31, 2003, to determine 6-month and lifetime prevalence rates of psychopathology in the deceased.

METHOD

We used 2 psychological autopsy methods: direct proxy-based interviews and medical chart reviews, together with telephone contacts with informants. Consensus DSM-IV diagnoses were formulated by clinical panels on the basis of the Structured Clinical Interviews I and II for DSM-IV complemented by medical charts.

RESULTS

Of the 109 suicide deaths identified by the coroner at the time of the study, we were able to investigate 102. At time of death, 65% of the suicide victims had a mood disorder, 59% had a substance-related disorder, and 42% had concurrent mood and substance-related disorders. The lifetime prevalence of substance-related disorders among these suicide victims was 66%. Finally, 52% of the suicide victims presented with a personality disorder; one-half of these were of the cluster B type.

CONCLUSIONS

Although treatment of depression has frequently been recognized as the focal point of clinically based suicide-prevention efforts, our results underscore substance-related disorders as a key dimension of completed suicide. Suicide-prevention programs should be designed to address this problem more directly.

Mortality patterns in infectious salmon anaemia virus outbreaks in New Brunswick, Canada

Mortality levels attributed to infectious salmon anaemia viral (ISAV) infections were examined at the net pen and site level in the 1996 smolt year class in three areas of New Brunswick, Canada. The year class in this region was the first known to have potential exposure to ISAV beginning at the time of seawater transfer. There was considerable variability in mortality patterns among net pen groups of fish. Net pen outbreak definitions were based on at least seven high mortality days in which there were at least 100 per 100 000 fish per day or >5% cumulative mortality for the study period. There were 106 net pen outbreaks in a study population consisting of 218 net pens. Although the number of new cases decreased as water temperature decreased, overall mortality levels at the study sites did not decrease noticeably. The median peak daily mortality rate during outbreaks was 492 per 100 000 fish per day, with 10% of cases experiencing >5200 mortalities per 100 000 fish per day. The median duration of outbreaks in net pens for which the fish were not slaughtered during the outbreak was 33 days and the median total loss in those outbreaks was 6600 per 100 000 fish.

Experiences of workplace bullying in a rural area

Employed people spend most of their waking hours in workplaces, but sometimes workplaces are made unbearable by bullying. This study examined how 21 people experienced workplace bullying in a rural and small city context and explored strategies for stopping workplace abuse. The research method of the learning circle was used because of its potential to reduce the isolation typically experienced by targets of workplace bullying, and its potential for peer dialogue and learning. This paper focuses on signs and experiences of workplace bullying, a phenomenon which produces both physical and emotional symptoms and often requires counseling.

Risk factors associated with mortalities attributed to infectious salmon anaemia virus in New Brunswick, Canada

Outbreaks of unexplained mortalities attributed to infectious salmon anaemia (ISA) were examined in the 1996 year class of Atlantic salmon in three regions of New Brunswick, Canada. A total of 218 net pens at 14 sites deemed to have been exposed to ISA virus (ISAV) were surveyed for mortality records and management, environmental and host characteristics. Based on definitions of mortality patterns, clinical ISA disease outbreaks occurred in 106 net pens. There were eight sites in which >50% of net pens experienced ISA outbreaks during the study period. Factors related to their potential role in transmission of virus to new sites or new net pens at the same site were identified as sea lice vectors, divers visiting multiple sites, sites belonging to companies with more than one site, exposure to other year classes at the site, and proximity to other infected net pens. Host resistance factors associated with greater risk of outbreaks were identified as larger groupings, general health following smolt transfer, stressful husbandry procedures during growout, and health or productivity during colder water periods. Despite very close proximity between sites, modification of these management factors would probably influence the severity of mortalities caused by ISAV.

Risk factors for outbreaks of infectious salmon anemia in farmed Atlantic salmon, Salmo salar

Infectious salmon anemia (ISA) is a viral disease occurring in farmed Atlantic salmon (Salmo salar) that is characterized by lethargy, anorexia, anemia and death. To control the disease in New Brunswick, Canada, 7.5 million fish from outbreak cages have been destroyed since 1997. Despite changes made by farmers, 2002 was the worst year ever for ISA losses in the region. We evaluated the associations between potential risk factors and ISA outbreaks in the Atlantic-salmon sites in New Brunswick. This was a multilevel study in which the site-level design was a retrospective cohort study while the cage-level design was a modified case-cohort study. The questionnaire was divided into site-level questions, cage-level questions and hatchery information. The important factors identified by this study can be categorized as environmental, farmer controlled or industry controlled according to the capacity to change or eliminate them. Environmental risk factors such as increasing the depth of the net (if nets were <or=9 m, odds ratio (OR)=3.34) and decreasing the depth of water underneath the net (if depth of water underneath the net >3m, OR=3.34) are for the most part dictated by site location. Wild pollock (Pollachius virens) in the cage reflects the number of wild pollock that live in the site location. If there were >or=1000 pollock in the cage, the odds of disease in the cage increased 4.43-fold. Risk factors that are under farm control include increasing the number of times that the salmon are treated for sea lice (OR=3.31 if lice treatments are <or=2 times), transferring small smolts into seawater (OR=2.40 if smolts weighed >99 g) and improving on the adaptation of smolts to seawater to reduce post-transfer mortalities (OR=4.52 if there was at least one cage with post-transfer mortalities >5%). The industry-controlled factors need to be addressed by the industry as a whole. Organizing boat travel to minimize the time and frequency of boats travelling to or by sites currently is being reviewed. This will be extremely important because the OR=9.43 if processing boats travel within 1 km of the site and the OR=4.03 if the site has dry feed delivered by the feed company. Because the hazard ratio increased stepwise from 1 if the nearest neighbor with ISA was >or=5 km up to 5.5 if the nearest site with ISA was within 0.5 km, increasing the distance between sites might be necessary for effective control.

Indoor environmental quality in homes of asthmatic children on the Elsipogtog Reserve (NB), Canada

OBJECTIVE

To inspect houses and analyze settled dust from 26 homes with asthmatic children in the Elsipogtog Reserve, New Brunswick, for contaminants known to be associated with respiratory symptoms. This pilot observational study was conducted in order to enable larger research into housing and health in Aboriginal communities.

METHODS

Twenty-six homes were subject to an informed inspection and settled dust collection from the child's bedroom. The fine dust (< 300 microm) was analyzed for endotoxin, house dust mite and fungal glucan concentrations, as well as for building-associated fungi.

RESULTS

The percentage of homes in this study that had mould damage was slightly higher than in much larger studies in other parts of Canada. Qualitatively, the causes of the water and mould damage were similar to those found in a larger study in nearby PEI. However, in a few cases, the type of damage found in Elsipogtog was at a more advanced stage. House dust mite allergens, endotoxin and fungal glucan concentrations in settled dust included values that have been associated with increased respiratory symptoms. This selection of houses was, on average, cleaner than many homes studied in Canada. CONCLUSION. Although the range of mould damage observed in this study was similar to that seen elsewhere in Canada, the underlying causes tended to reflect more serious maintenance problems. A systematic evaluation of mould damage, on a community-wide basis, is a useful process to set priorities for repair.

Assessment of infectious salmon anaemia virus prevalence for different groups of farmed Atlantic salmon, Salmo salar L., in New Brunswick

Abstract Infectious salmon anaemia (ISA) virus (ISAV) has been causing disease in New Brunswick since 1996. As a control measure, all fish in an outbreak cage are killed. The objective of this study was to compare ISAV prevalence in cages experiencing an outbreak with healthy cages from the same farm, neighbouring farms and distant farms. Atlantic salmon from five different groups were tested using an RT-PCR test. Groups included moribund fish from a cage experiencing an outbreak (A), healthy fish from an outbreak cage (B), healthy fish from a negative cage from a farm experiencing an outbreak in a different cage (C), healthy fish from a negative farm near an outbreak farm (D), and healthy fish sampled at a negative farm located in an area with only negative farms (E). Apparent prevalences (standard error) for the different groups (A-E) were 0.94 (+/-0.026), 0.41 (+/-0.062), 0.29 (+/-0.040), 0.08 (+/-0.037) and 0.08 (+/-0.037), respectively. All groups were significantly different (P < 0.002) from each other except for groups B and C and groups D and E. Because the prevalence of the virus was significantly higher in the outbreak cage (B) compared with other sites, early harvest of outbreak cages will remove one source of virus. However, ISA negative cages (C) that remain on the positive farm may potentially act as a viral reservoir.

Lifestyle risk factors for chronic disease by family origin among children in multiethnic, low-income, urban neighborhoods

OBJECTIVES

To describe the prevalence of lifestyle risk factors (LRF) for chronic disease by family origin (FO) among children in multiethnic, low-income, urban neighborhoods.

DESIGN

Cross-sectional analysis.

SETTING

16 elementary schools located in disadvantaged, multiethnic neighborhoods in Montreal, Canada.

PARTICIPANTS

4659 schoolchildren aged 9-12 in grades 4-6.

OUTCOME MEASURES

Smoking, level of physical activity, dietary habits, body mass index, sedentary behavior.

METHODS

Subjects completed self-report questionnaires on sociodemographic characteristics and lifestyle behaviors; height and weight were measured in a standardized protocol. Fourteen FO groupings were identified based on language(s) spoken and countries of birth of both subjects and parents. We tested FO as an independent correlate of having 2 or more LRF, using the generalized estimating equations method.

RESULTS

Relative to Canadian children, a higher proportion of Haitian, Portuguese, and other Central American/Caribbean children had 2 or more LRF, the proportion was similar among Cambodian, Vietnamese, Chinese, South American, East European, Arabic, Italian, and South Asian children, and lower among Salvadorean children.

CONCLUSION

Prevention programs for youth should take differential distribution of LRF by ethnicity into account.

Peer sexual harassment in adolescence: the function of gender

The author describes the sexual harassment experiences of 565 male and female students in Grades 9 through 11 and discusses the influence of the social construction of gender on those experiences. The sample was drawn from 12 schools in 2 Canadian provinces. The study employed a retrospective correlational survey design, using self-report questionnaires administered in class. The results indicate that sexual harassment is pervasive among both male and female adolescents but is particularly problematic for girls due to their qualitatively different harassment experiences. Both girls and boys reported gender harassment to be, in general, more upsetting than unwanted sexual advances. Girls employed a greater variety of coping strategies than boys; however, for both sexes passive coping strategies were predominant. The author offers recommendations related to school health programming and discusses the role of the school nurse.

Serological evidence of infectious salmon anaemia virus (ISAV) infection in farmed fishes, using an indirect enzyme-linked immunosorbent assay (ELISA)

Antibody detection tests are rarely used for diagnostic purposes in fish diseases. Infectious salmon anaemia (ISA) caused by ISA virus (ISAV) is an emerging disease of Atlantic salmon Salmo salar L. The virus has also been isolated from diseased coho salmon Oncorhynchus kisutch in Chile. An indirect enzyme-linked immunosorbent assay (ELISA) that should facilitate serodiagnosis of ISAV infection, the study of epidemiology, and the control of ISA in farmed fishes has been developed using purified ISAV as the coating antigen, and monoclonal antibodies that detect fish immunoglobulins bound to the antigen on the plate. Application of the test to a random sample of farmed Atlantic salmon from the Bay of Fundy, New Brunswick, Canada, positively identified 5 of the 7 ISAV RT-PCR-positive fish, and all 10 RT-PCR-negative fish were also negative in the ELISA. Some RT-PCR-negative fish had an elevated non-specific antibody reactivity suggestive of chronic infection or resistance to ISAV. This test was also able to detect 11 of the 14 coho salmon pooled serum samples from a clinically affected farm in Chile that were positive by the virus neutralization (VN) test, and 2 of the 4 VN-negative samples. We conclude that this ELISA would be suitable as a routine test for ISAV infection or for assessing ISAV vaccine efficacy before placing smolts in sea cages, and for testing fishes in sea cages to detect level of resistance to ISA. The assay enables vaccination in combination with depopulation control methods.

Strain variation, based on the hemagglutinin gene, in Norwegian ISA virus isolates collected from 1987 to 2001: indications of recombination

Infectious salmon anemia (ISA) is caused by a virus that probably belongs to the Orthomyxoviridae and was first recorded in Norway in 1984. The disease has since spread along the Norwegian coast and has later been found in Canada, Scotland, the Faroe Islands, Chile, and the USA. This study presents sequence variation of the hemagglutinin gene from 37 ISA virus isolates, viz. one isolate from Scotland, one from Canada and 35 from Norway. The hemagglutinin gene contains a highly polymorphic region (HPR), which together with the rest of the gene sequence provides a good tool for studies of epizootics. The gene shows temporal and geographical sequence variation, where certain areas are dominated by distinct groups of isolates. Evidence of transmission of ISA virus isolates within and between regions is given. It is suggested that the hemagglutinin gene from different isolates may recombine. Possible recombination sites are found within the HPR and in the 5'-end flanking region close to the HPR.

[Maternal anemia in the southeast and northeast regions of New Brunswick and the impact on hematological parameters and the growth of the newborn]

The prevalence of anaemia remains a major nutritional problem in industrialized countries. The aim of this study was to compare the prevalence of maternal anaemia in southeastern and northeastern areas of New Brunswick and to identify a potential interaction between maternal haematologic indices and the growth, hemoglobin (Hb) and hematocrit (Ht) of newborns. In this retrospective study, 952 obstetric and paediatric records, including 654 from the southeastern area (Greater Moncton) and the rest from the northeastern area (Acadian Peninsula) of New Brunswick, were investigated. The prevalence of maternal anaemia was 21.4% in the Greater Moncton area, compared to 11.5% in the Peninsula. The majority of anaemic women suffered from a light form of anaemia, mainly in the third trimester. Immediately after delivery, 52% of women from Greater Moncton and 40% from the Acadian Peninsula had Hb below normal. A positive correlation was observed between maternal Hb and newborn Hb and between maternal Ht and newborn Hb. Results indicate that maternal anaemia is prevalent in both areas under study and confirm the importance of implementing effective prevention measures.

Simple nutrition screening tools for healthcare facilities: development and validity assessment

The purpose of nutrition screening is to identify individuals at high nutritional risk. Given that dietitians cannot always carry out screening in health-care facilities, tools should be simple and based on data obtained from the nursing admission questionnaire. This study was conducted to develop timely and valid tools for screening protein-energy malnutrition (PEM). A dietetic technician administered an initial screening tool to 160 subjects recruited from two settings. This tool comprised nine PEM risk factors. The sample included 54 adults in acute care, 57 elderly adults in acute care, and 49 elderly adults in long-term care. Dietitians performed comprehensive nutritional assessments to determine the validity of this screening tool. Stepwise regression analysis revealed significant risk factors among those included in the initial screening. These risk factors were considered during development of the first simple screening tool, which encompassed body mass index (BMI) and percentage of weight loss, and classified subjects as having low or high PEM risk levels. A second tool using BMI and albumin level was tested in cases where an albumin measurement was available upon admission. These simple tools had validity indices of 75.9% or higher, except in adults in acute care; sensitivity was low in this group. The tools proved helpful in establishing dietitians' priorities for involvement and in initiating early nutritional care.

Cutaneous blastomycosis in New Brunswick: case report

Blastomycosis is a fungal infection of immunocompetent hosts. We present a case of cutaneous blastomycosis acquired in New Brunswick, which provides evidence that this disease is endemic in Atlantic Canada. This case also demonstrates that the diagnosis of blastomycosis may be elusive. Perseverance, a high index of clinical suspicion and close cooperation with the microbiology laboratory may be required to diagnose this uncommon condition.

Health outcomes of elementary school students in New Brunswick. The education perspective

With data from the New Brunswick School Climate Study (N = 6,883 students from 147 schools), this study examined individual differences in and school effects on health outcomes of students. Results of hierarchical linear modeling showed that females reported experiencing more physical health problems, eating less healthy food, and doing fewer exercises than males. Students of high socioeconomic status (SES) reported eating more healthy food and doing more exercises than students of low SES. Native students reported experiencing more physical health problems and eating less healthy food than nonnative students. Students of single parents reported eating more healthy food and exercising more than students of both parents. Schools showed effects on health outcomes over and above the effects of students. Students in schools with high SES and positive disciplinary climate reported fewer physical and mental health problems. Students in large schools reported less healthy food intake and fewer physical exercises.

Air pollution, aeroallergens and cardiorespiratory emergency department visits in Saint John, Canada

Existing studies of the association between air pollution, aeroallergens and emergency department (ED) visits have generally examined the effects of a few pollutants or aeroallergens on individual conditions such as asthma or chronic obstructive pulmonary disease. In this study, we considered a wide variety of respiratory and cardiac conditions and an extensive set of pollutants and aeroallergens, and utilized prospectively collected information on possible effect modifiers which would not normally be available from purely administrative data. The association between air pollution, aeroallergens and cardiorespiratory ED visits (n = 19,821) was examined for the period 1992 to 1996 using generalized additive models. ED visit, air pollution and aeroallergen time series were prefiltered using LOESS smoothers to minimize temporal confounding, and a parsimonious model was constructed to control for confounding by weather and day of week. Multipollutant and multi-aeroallergen models were constructed using stepwise procedures and sensitivity analyses were conducted by season, diagnosis, and selected individual characteristics or effect modifiers. In single-pollutant models, positive effects of all pollutants but NO2 and COH were observed on asthma visits, and positive effects on all respiratory diagnosis groups were observed for O3, SO2, PM10, PM2.5, and SO4(2-). Among cardiac conditions, only dysrhythmia visits were positively associated with all measures of particulate matter. In the final year-round multipollutant models, a 20.9% increase in cardiac ED visits was attributed to the combination of O3 (16.0%, 95% CI 2.8-30.9) and SO2 (4.9%, 95%CI 1.7-8.2) at the mean concentration of each pollutant. In the final multipollutant model for respiratory visits, O3 accounted for 3.9% of visits (95% CI 0.8-7.2), and SO2 for 3.7% (95% CI 1.5-6.0), whereas a weak, negative association was observed with NO2. In multi-aeroallergen models of warm season asthma ED visits, Ascomycetes, Alternaria and small round fungal spores accounted for 4.5% (95% CI 1.8-7.4), 4.7% (95% CI 1.0-8.6) and 3.0% (95% CI 0.8-5.1), respectively, of visits at their mean concentrations, and these effects were not sensitive to adjustment for air pollution effects. In conclusion, we observed a significant influence of the air pollution mix on cardiac and respiratory ED visits. Although in single-pollutant models, positive associations were noted between ED visits and some measures of particulate matter, in multipollutant models, pollutant gases, particularly ozone, exhibited more consistent effects. Aeroallergens were also significantly associated with warm season asthma ED visits.

Interactive mortality factors in common loons from Maritime Canada

Between August 1992 and November 1995, 31 moribund or dead common loons (Gavia immer) found in the three Maritime provinces of Canada (New Brunswick, Nova Scotia, Prince Edward Island) were necropsied. Eight of these birds were in good body condition and died acutely from drowning or trauma. The remaining 23 birds were in poor body condition and had either chronic lead poisoning, respiratory mycosis, or oil contamination of their plumage. Loons in poor body condition had significantly higher numbers of intestinal trematodes and significantly higher levels of total renal mercury than loons in good body condition. Therefore, poor body condition in many loons was associated with two or more concurrent potential disease processes, although we could not establish a cause-effect relationship among these processes in individual birds. These results suggest that mortality in chronically ill wild animals can result from synergism among several potentially debilitating agents present in their environment.

Analysis of infectious laryngotracheitis virus isolates from Ontario and New Brunswick by the polymerase chain reaction

The polymerase chain reaction (PCR) was used to amplify DNA of infectious laryngotracheitis virus (ILTV) isolates obtained from field specimens. The examined 47 samples included 37 isolates representing 35 cases of infectious laryngotracheitis from Ontario and 10 isolates originating from 10 field cases in New Brunswick. The viruses were grown in either embryonated chicken eggs or cell culture, the DNA extracted and amplified using primers designed from the sequence information of a 1.1 kb BamHI fragment of the Ontario 1598 ILTV strain. Thirty-four of the Ontario isolates and all of the New Brunswick isolates were amplified successfully. This suggests that the selected primers would be useful for the majority of the isolates encountered in outbreaks of ILTV.