Search

Varicella occurs at an older age in tropical compared to cold climates. Migrants from tropical countries provide the opportunity to gain insights into observed global differences in varicella epidemiology. Severity of varicella increases with age thus, description of risk factors for varicella susceptibility will identify those who would benefit most from vaccination. A total of 1480 migrants, with a mean age of 32 years, were recruited in the pre-vaccination period (2002-2004) in Montreal, Canada. A questionnaire was administered and serum varicella antibodies were measured. Overall 6% were susceptible and ranged from 0·8% to 14·1% in subgroups. Risk factors for susceptibility were younger age, recent arrival, and originating from a tropical country. This could be modified by conditions that increased the probability of person-to-person spread of varicella through direct contact in source countries such as larger community size or household crowding. Many new young adult migrants would benefit from targeted varicella vaccination programmes.

We investigated an outbreak of Salmonella Enteritidis (SE) infections linked to raw mung bean sprouts in 2000 with two case-control studies and reviewed six similar outbreaks that occurred in 2000-2002. All outbreaks were due to unusual phage types (PT) of SE and occurred in the United States (PT 33, 1, and 913), Canada (PT 11b and 913), and The Netherlands (PT 4b). PT 33 was in the spent irrigation water and a drain from one sprout grower. None of the growers disinfected seeds at recommended concentrations. Only two growers tested spent irrigation water; neither discarded the implicated seed lots after receiving a report of Salmonella contamination. We found no difference in the growth of SE and Salmonella Newport on mung beans. Mung bean sprout growers should disinfect seeds, test spent irrigation water, and discontinue the use of implicated seed lots when pathogens are found. Laboratories should report confirmed positive Salmonella results from sprout growers to public health authorities.

Background: The efficacy of lipid-lowering therapy (LLT) has been well established for patients with preexisting coronary artery disease (CAD). However, limited information is available assessing the extent to which these medications are prescribed in academic medical centers., Methods: The use of LLT for patients with CAD was prospectively evaluated in 825 men and women who were recruited from 16 academic medical centers in the United States and Canada to participate in the Prospective Evaluation of the Vascular Events of Norvasc Trial (PREVENT). The assessment of LLT use during the 3-year trial was evaluated in patients receiving amlodipine therapy and placebo; levels of low-density lipoprotein cholesterol (LDL-C) were used to assess the impact of LLT., Results: Despite a baseline prevalence of LLT in 42% of men (38% in 1994), half of the patients had high levels of LDL-C (>3.36 mmol [>130 mg/dL]). During the subsequent 3 years, the prevalence of elevated LDL-C levels dropped in men (29%) but remained stagnant in women (48%). These changes were associated with increased LLT in men (55%) but not in women (35%) (P = .04). In 1994, the LDL-C target goal (<2.59 mmol/L [<100 mg/dL]) was attained in 17% of men and 6% of women (P = .006). At study completion in 1997, the LDL-C target goal was achieved in 31% of men and only 12% of women (P = .001)., Conclusions: This study highlights the relatively low treatment rates of hyperlipidemia among patients with CAD overall and women in particular who were participating in a clinical trial at academic medical centers in the United States and Canada. Because LLT has been proven to reduce future cardiovascular events, these results suggest that more intensive efforts should be promoted in order to maximize CAD reduction.

Objective: To assess the importance of baseline characteristics including medical history, indicators of current disease status, therapeutic drug use, in vitro drug susceptibility, immune status and mycobacterial load on bacteriologic response and survival in HIV-positive patients with Mycobacterium avium complex (MAC) bacteremia., Design: An observational substudy of an open-label randomized controlled trial of two alternative therapeutic regimens for MAC., Setting: Twenty-four hospital-based HIV clinics in 16 Canadian cities., Main Outcome Measures: The main outcome measures were survival and bacteriologic response, defined by consecutive negative blood cultures for MAC at least 2 weeks apart within 16 weeks of study entry., Results: Prior AIDS diagnosis, low Karnofsky score, active unstable AIDS-related conditions, absence of antiretroviral therapy and absence of Pneumocystis carinii pneumonia prophylaxis were associated with shorter survival by univariate regression using the proportional hazards model. On multivariate analysis, antiretroviral therapy was not an independent predictor of mortality, and previous rifabutin prophylaxis was independently associated with poor survival outcomes, a result consistent across study treatment. Using a logistic regression model, baseline quantitative mycobacterial load [relative odds of clearing, 1.97 for a decrease of 1 log10 colony forming count; 95% confidence interval (CI), 1.36-2.87; P < 0.001] and Karnofsky score were the only statistically significant univariate predictors of clearance, although previous prophylaxis with rifabutin was also a significant predictor in a multivariate model (relative odds of clearing, 0.39; 95% CI, 0.17-0.88; P < 0.05)., Conclusions: This study indicates that although the level of MAC bacteremia is an important predictor of clearance, it is not associated with survival.