Evaluation of the use of oseltamivir prophylaxis in the control of influenza outbreaks in long-term care facilities in Alberta, Canada: a retrospective provincial database analysis.

OBJECTIVES: To evaluate the impact of oseltamivir prophylaxis in the management and control of influenza outbreaks in long-term care facilities in Alberta, Canada. SETTING AND PARTICIPANTS: Long-term care facilities where 127 influenza outbreaks were reported to public health authorities in Alberta, Canada, during two influenza seasons from 2013 to 2015. DESIGN AND OUTCOME MEASURES: Using routinely collected surveillance and administrative data, we examined the association between decision-making time for oseltamivir recommendation as prophylaxis strategy for influenza outbreaks in long-term care facilities (explanatory variable) and the duration of an influenza outbreak, the postprophylaxis risk of influenza-like illness and hospitalisation among residents of long-term care facilities in Alberta (outcome variables) using multivariable linear and Poisson regression models. RESULTS: Oseltamivir prophylaxis decision-making time was positively associated with the postintervention duration of an outbreak, with a 1-day delay in making decision on oseltamivir prophylaxis associated with 2.22 (95% CI 1.37 to 3.06) more days of the duration of an outbreak after controlling for potential confounding effect of the number of residents at risk at intervention, outbreak progression time, prevalence of influenza-like illness during outbreak progression, facility location, presence of mixed strain and based on optimal timing of oseltamivir prophylaxis. Although not statistically significant, a 1-day delay in making decision on oseltamivir prophylaxis was associated with a 5% (95% CI -1% to 11%) increase in the postintervention risk of influenza-like illness, and a 6% (95% CI -8% to 22%) increase in the postintervention risk of hospitalisation after controlling for the same potential confounders. CONCLUSIONS: Our study demonstrated benefits of using oseltamivir prophylaxis to shorten the duration of influenza outbreaks; however, there were no significant differences in the influenza-like illness and hospitalisation risk occurring after the intervention. Surveillance data may offer means of rapid evaluation of oseltamivir prophylaxis in long-term care facilities as a public health measure.

Assessment of HIV Knowledge in Correctional Facility Health Care Workers: A Pilot Study of an Educational Intervention.

HIV rates are disproportionately higher in the incarcerated compared to the general population. Unfortunately, HIV sero-positive inmates report perceived discrimination and missed antiretroviral doses. Correctional facility nursing competency in HIV management may mitigate these concerns. Using validated knowledge instruments, the authors measured baseline HIV knowledge in correctional facility nurses from 3 correctional facilities in Alberta, Canada, and quantified changes after a targeted educational workshop. Basic HIV knowledge increased significantly, whereas perceived need for further HIV education significantly decreased postintervention. This study demonstrates that correctional facility nurses may not receive ideal HIV education during employment and that targeted HIV workshops can significantly increase knowledge and confidence when caring for affected individuals.

Determining rubella immunity in pregnant Alberta women 2009-2012.

Rubella IgG levels for 157,763 pregnant women residing in Alberta between 2009 and 2012 were analyzed. As there have been no reported cases of indigenous rubella infection in Canada since 2005, there has been a lack of naturally acquired immunity, and the current prenatal population depends almost entirely on vaccine induced immunity for protection. Rubella antibody levels are significantly lower in younger maternal cohorts with 16.8% of those born prior to universal vaccination programs (1971-1980), and 33.8% of those born after (1981-1990) having IgG levels that are not considered protective (<15 IU/mL). Analysis across pregnancies showed only 35.0% of women responded with a 4-fold increase in antibody levels following post-natal vaccination. Additionally, 41.2% of women with antibody levels <15 IU/mL had previously received 2 doses of rubella containing vaccine. These discordant interpretations generate a great deal of confusion for laboratorians and physicians alike, and result in significant patient follow-up by Public Health teams. To assess the current antibody levels in the prenatal population, latent class modeling was employed to generate a two class fit model representing women with an antibody response to rubella, and women without an antibody response. The declining level of vaccine-induced antibodies in our population is disconcerting, and a combined approach from the laboratory and Public Health may be required to provide appropriate follow up for women who are truly susceptible to rubella infection.

Transmission of pandemic influenza A (H1N1) 2009 within households: Edmonton, Canada.

BACKGROUND: In April 2009, a novel influenza A, subtype H1N1, now referred to as the Pandemic (H1N1) 2009 virus (pH1N1), began circulating in countries around the world. Describing the transmission characteristics of this novel influenza A virus is important to predict current, and future, disease spread. The Public Health response to the first wave of pH1N1 in Alberta focused on the identification and management of secondary cases within households. OBJECTIVES: The purpose of this study was to describe transmission characteristics of pH1N1 in households in Edmonton, the capital city of Alberta, during the first wave, and to identify the serial interval and secondary attack rate (SAR) in this setting. STUDY DESIGN: This is a prospective analysis of pH1N1 household transmission within 87 urban Canadian households between April 30 and June 9, 2009; with each household having at least one laboratory-confirmed case. The secondary attack rate was calculated in the 262 household contacts using a weighted average by number of susceptible individuals in each household. The serial interval, or time to illness in secondary cases, was analyzed using survival analysis with a Weibull model. RESULTS: Within the 87 households, 42 (48.3%) had no secondary cases develop; 25 (28.7%) had one secondary case develop; and 20 (22.9%) had more than one secondary case develop. The secondary attack rate did not decrease with increasing household size and households with two members exhibited the lowest secondary attack rate at 14.1%. Children under the age of 19, and individuals with an underlying medical condition, were at increased risk (p<0.05) of becoming a secondary case. The overall secondary attack rate among the 262 susceptible household contacts was 30.2% (95% CI: 12.6-52.2). The median serial interval for pH1N1 transmission was 3.4 days (95% CI: 2.9-3.9). CONCLUSIONS: The identified transmission characteristics of pH1N1 among Canadian households differ slightly from other previously reported North American estimates, but are in keeping with historical transmission rates of pandemic influenza viruses.

Identification and epidemiology of severe respiratory disease due to novel swine-origin influenza A (H1N1) virus infection in Alberta.

BACKGROUND: In March 2009, global surveillance started detecting cases of influenza-like illness in Mexico. By mid-April 2009, two pediatric patients were identified in the United States who were confirmed to be infected by a novel influenza A (H1N1) strain. The present article describes the first identified severe respiratory infection and the first death associated with pandemic H1N1 (pH1N1) in Canada. METHODS: Enhanced public health and laboratory surveillance for pH1N1 was implemented throughout Alberta on April 24, 2009. Respiratory specimens from all patients with a respiratory illness and travel history or those presenting with a severe respiratory infection requiring hospitalization underwent screening for respiratory viruses using molecular methods. For the first severe case identified and the first death due to pH1N1, histocompatibility leukocyte antigens were compared by molecular methods. RESULTS: The first death (a 39-year-old woman) occurred on April 28, 2009, and on May 1, 2009, a 10-year-old child presented with severe respiratory distress due to pH1N1. Both patients had no travel or contact with anyone who had travelled to Mexico; the cases were not linked. Histocompatibility antigen comparison of both patients did not identify any notable similarity. pH1N1 strains identified in Alberta did not differ from the Mexican strain. CONCLUSION: Rapid transmission of pH1N1 continued to occur in Alberta following the first death and the first severe respiratory infection in Canada, which were identified without any apparent connection to Mexico or the United States. Contact tracing follow-up suggested that oseltamivir may have prevented ongoing transmission of pH1N1.

A multi-function public health surveillance system and the lessons learned in its development: the Alberta Real Time Syndromic Surveillance Net.

OBJECTIVE: We describe a centralized automated multi-function detection and reporting system for public health surveillance--the Alberta Real Time Syndromic Surveillance Net (ARTSSN). This improves upon traditional paper-based systems which are often fragmented, limited by incomplete data collection and inadequate analytical capacity, and incapable of providing timely information for public health action. METHODS: ARTSSN concurrently analyzes multiple electronic data sources in real time to describe results in tables, charts and maps. Detected anomalies are immediately disseminated via alerts to decision-makers for action. RESULTS: ARTSSN provides richly integrated information on a variety of health conditions for early detection of and prompt action on abnormal events such as clusters, outbreaks and trends. Examples of such health conditions include chronic and communicable disease, injury and environment-mediated adverse incidents. DISCUSSION: Key advantages of ARTSSN over traditional paper-based methods are its timeliness, comprehensiveness and automation. Public health surveillance of communicable disease, injury, environmental hazard exposure and chronic disease now occurs in a single system in real time year round. Examples are given to demonstrate the public health value of this system, particularly during Pandemic (H1N1) 2009.

Modifiable risk factors for term large for gestational age births.

To determine modifiable and nonmodifiable risk factors for term large for gestational age (T-LGA) births in Northern and Central Alberta and their public health importance, a retrospective cohort study (n = 115,198) of singleton live births (1996-2003) was conducted using maternal and newborn data from a provincial perinatal database. After adjusting for potential confounders, predictors of T-LGA births included prepregnancy weight 91 kg or greater, multiparity, and previous LGA birth. The strongest modifiable predictor was prepregnancy weight 91 kg or greater (OR = 2.52; CI 2.39, 2.65). The population-attributable risk percentage for prepregnancy weight 91 kg or greater was 10%.

Histoplasmosis cluster, golf course, Canada.

We report a cluster of 4 cases of acute histoplasmosis (1 culture proven and 3 with positive serology, of which 2 were symptomatic) associated with exposure to soil during a golf course renovation. Patients in western Canada with compatible symptoms should be tested for histoplasmosis, regardless of their travel or exposure history.