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The occurrence of influenza in different climates is shown to be associated with multiple meteorological factors. Incidence of influenza has been reported to increase during rainy seasons in tropical climates and during dry, cold months of winter in temperate climates. This study was designed to explore the role of absolute humidity (AH), relative humidity (RH), temperature, and wind speed (WS) on influenza activity in Toronto area, Ontario, Canada. Environmental data obtained from four meteorological stations in Toronto area, for the period of January 1, 2010 to December 31, 2015, were linked to patient's influenza data obtained for the same locality and period. Data were analyzed using correlation, negative binomial regressions with linear predictors and splines to capture the non-linear relationship between exposure and outcomes. Our study found a negative association of both AH and temperature with influenza A and B viruses. Effect of RH in influenza A and B was controversial Temperature fluctuation was associated with increased influenza B virus. Influenza virus was less likely to be detected from community patients than those tested as part of an institutional outbreak investigation. This could be more indicative of nosocomial transmission, rather than climactic factors. The non-linear nature of the relation between influenza A virus and temperature and influenza B virus and AH, RH and temperature could explain the complexity and variation between influenza A and B viruses. Predicting influenza activity is important for the timing of disease prevention and control measures as well as for resource allocation. [ABSTRACT FROM AUTHOR]

We examined malaria cases reported to Ontario’s public health surveillance systems from 1990 through 2009 to determine how temporal scale (longitudinal, seasonal), spatial scale (provincial, health unit), and demography (gender, age) contribute to Plasmodium infection in Ontario travellers. Our retrospective study included 4,551 confirmed cases of imported malaria reported throughout Ontario, with additional analysis at the local health unit level (i.e., Ottawa, Peel, and Toronto). During the 20-year period, Plasmodium vivax accounted for 50.6% of all cases, P. falciparum (38.6%), Plasmodium sp. (6.0%), P. ovale (3.1%), and P. malariae (1.8%). During the first ten years of the study (1990–1999), P. vivax (64% of all cases) was the dominant agent, followed by P. falciparum (28%); however, during the second ten years (2000–2009) the situation reversed and P. falciparum (55%) dominated, followed by P. vivax (30%). The prevalence of P. falciparum and P. vivax cases varied spatially (e.g., P. falciparum more prevalent in Toronto, P. vivax more prevalent in Peel), temporally (e.g. P. falciparum incidence increased during the 20-year study), and demographically (e.g. preponderance of male cases). Infection rates per 100,000 international travellers were estimated: rates of infection were 2× higher in males compared to females; rates associated with travel to Africa were 37× higher compared to travel to Asia and 126× higher compared to travel to the Americas; rates of infection were 2.3–3.5× higher in June and July compared to October through March; and rates of infection were highest in those 65–69 years old. Where exposure country was reported, 71% of P. falciparum cases reported exposure in Ghana or Nigeria and 63% of P. vivax cases reported exposure in India. Our study provides insights toward improving pre-travel programs for Ontarians visiting malaria-endemic regions and underscores the changing epidemiology of imported malaria in the province. [ABSTRACT FROM AUTHOR]

Objective: Online and lab-based experiments examining the impact of alcohol labels typically test a one-time exposure to labels and assess short-term, non-behavioural outcomes. These studies do not simulate a real-world label dose or assess actual alcohol use. This pilot aimed to develop a new protocol for testing alcohol labels that better reflects real-world exposure by presenting labels on consumers' own alcohol products over time and assessing effects on several outcomes, including alcohol use., Method: Forty alcohol consumers in Canada completed an online baseline survey, were randomized to one of two label conditions (Control: recycle label; Intervention: cancer warning label), mailed labels according to their assigned condition, and asked to affix one label to all alcohol containers in their home over the 29 days in February 2024. Online surveys assessed label effects at three follow-up points, and SMS texts were used to promote protocol adherence., Results: The protocol had high adherence and retention, with no differences between conditions. Survey response rates remained high at follow-ups, ranging between 80%-100%. All participants (100%) said they were satisfied with the study and 94% would recommend to a friend. Preliminary label effectiveness results were promising - between baseline and Day 29, the mean number of standard drinks (SD) consumed in the past 7 days decreased in the intervention condition by -4.2SD (45%), and in the control by -0.3SD (3%)., Conclusions: Findings suggest this proof-of-principle protocol affixing labels on consumers' own alcohol products offers the potential for greater experimental control and real-world label dose than online or lab-based experiments.