Dataset Information

The United States and Canada as a coupled epidemiological system: an example from hepatitis A.

ABSTRACT: BACKGROUND: Hepatitis A (HA) is a low-incidence, non-endemic disease in Canada and the United States (US). However, a large difference in HA incidence between Canada and HA-endemic countries has made travel an important contributor to hepatitis A prevalence in Canada. There is also a (smaller) incidence differential between Canada and the US. Although the US has only moderately higher HA incidence, the volume of travel by Canadians to the US is many times higher than travel volume to endemic countries. Hence, travel to the US may constitute a source of low to moderate risk for Canadian travelers. To our knowledge, travel to the US has never been included as a potential risk factor for HA infection in Canadian epidemiologic analyses. The objective of this study was to use dynamic models to investigate the possible effects on hepatitis A incidence in Canada due to (1) implementing vaccination in the US, and (2) varying the volume of travel by Canadians to the US. METHODS: We developed and analyzed age-structured compartmental models for the transmission and vaccination of hepatitis A, for both Canada and the US. Models were parameterized using data on seroprevalence, case reporting, and travel patterns. The potential effect of hepatitis A prevalence in the US on hepatitis A prevalence in Canada was captured through a term representing infection of Canadians due to travel in the US. RESULTS: The model suggests that approximately 22% of HA cases in Canada in the mid 1990s may have been attributable to travel to the US. A universal vaccination programme that attained 70% coverage in young children in the US in the mid 1990s could have reduced Canadian incidence by 21% within 5 years. CONCLUSION: Since not all necessary data were available to parameterize the model, the results should be considered exploratory. However, the analysis shows that, under plausible assumptions, the US may be more important for determining HA prevalence in Canada than is currently supposed. As international travel continues to grow, making vaccination policies ever more relevant to populations beyond a country's borders, such multi-country models will most likely come into wider use as predictive aids for policy development.

SUBMITTER: Amariei R

PROVIDER: S-EPMC2292190 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The United States and Canada as a coupled epidemiological system: an example from hepatitis A.

Amariei Raluca R Willms Allan R AR Bauch Chris T CT

BMC infectious diseases 20080228

<h4>Background</h4>Hepatitis A (HA) is a low-incidence, non-endemic disease in Canada and the United States (US). However, a large difference in HA incidence between Canada and HA-endemic countries has made travel an important contributor to hepatitis A prevalence in Canada. There is also a (smaller) incidence differential between Canada and the US. Although the US has only moderately higher HA incidence, the volume of travel by Canadians to the US is many times higher than travel volume to ende ...[more]

PMID: 18307785

Similar Datasets

Project description:Interest in the role of fibrates intensified after the publication of the negative results from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, which assessed therapy with fenofibrate plus statins. The evidence for clinical benefit in outcomes with the use of fibrates is heavily weighted on the use of the older fibrates such as gemfibrozil and clofibrate.To examine trends in the current use of fibrates and to examine the relationship between differences in the availability and use of brand-name vs generic formulations of fenofibrate and the economic implications in the United States compared with Canada.Population-level, observational cohort study using IMS Health data from the United States and Canada of patients prescribed fibrates between January 2002 and December 2009.Fibrate prescriptions dispensed and expenditures.In the United States, fibrate prescriptions dispensed increased from 336 prescriptions/100,000 population in January 2002 to 730 prescriptions/100,000 population in December 2009, an increase of 117.1% (95% confidence interval [CI], 116.0%-117.9%), whereas in Canada, fibrate prescriptions increased from 402 prescriptions/100,000 population in January 2002 to 474 prescriptions/100,000 population in December 2009, an increase of 18.1% (95% CI, 17.9%-18.3%) (P <.001). In the United States, fenofibrate prescriptions dispensed increased from 150 prescriptions/100,000 population in January 2002 to 440 prescriptions/100,000 population in December 2009, an increase of 159.3% (95% CI, 157.7%-161.0%), comprising 47.9% of total fibrate prescriptions in 2002 and 65.2% in 2009. In Canada, fenofibrate prescriptions increased from 321 prescriptions/100,000 population in January 2002 to 429 prescriptions/100,000 population in December 2009. The annual ratio of generic to brand-name fenofibrate use in the United States ranged from 0:1 to 0.09:1 between 2002 and 2008, while the ratio in Canada steadily increased from 0.51:1 to 1.89:1 between 2005 and 2008. In the United States, crude fenofibrate expenditures increased from $11,535/100,000 population/month in 2002 to $44,975/100,000 population/month in 2009, while the rates in Canada declined from $17,695/100,000 population/month in 2002 to $16,112/100,000 population/month in 2009. Fibrate expenditures per 100,000 population were 3-fold higher in 2009 in the United States compared with Canada.During the past decade, prescriptions for fibrates (particularly fenofibrate) increased in the United States, while prescriptions for fibrates in Canada remained stable.

Project description:ObjectivesThe aim of the study was to determine whether selected sociodemographic and hepatitis B virus (HBV)-specific clinical factors are associated with health-related quality of life (HRQoL) among pediatric patients chronically infected with HBV.MethodsChildren with chronic HBV enrolled in the Hepatitis B Research Network completed the Child Health Questionnaire at study entry. Caregivers of children 5 to <10 years completed the parent-reported form (CHQ-Parent Report Form); youth 10 to <18 years completed the child-reported CHQ-Child Report Form. We examined univariable associations of the Child Health Questionnaire scores with selected independent variables: sex, adoption status, maternal education, alanine aminotransferase (U/L), aspartate aminotransferase-to-platelet ratio index, and HBV-specific symptom count.ResultsA total of 244 participants (83 young children 5-<10 years, 161 youth 10-<18 years) were included, all HBV treatment-naïve. Among young children, increased alanine aminotransferase level was negatively associated with CHQ-Parent Report Form psychosocial summary t score (r = -0.28, P = 0.01). No other subscale comparisons for young children were statistically significant. Among youth, adoption was associated with better physical functioning and general health (P < 0.01). Higher maternal education was associated with better role/functioning-physical and -emotional scores (P < 0.05). Maternal education and adoption status were linked with adoption associated with higher maternal education. Increased symptom count in youth was associated with worse HRQoL in subscales measuring bodily pain, behavior, mental health, and self-esteem (P < 0.01).ConclusionsAlthough overall HRQoL is preserved in children with chronic HBV, some sociodemographic and HBV-related clinical factors were associated with impaired HRQoL in our pediatric patients at baseline. Measurement of HRQoL can focus resources on education and psychosocial support in children and families most in need.

Project description:Importance:Small studies and anecdotal evidence suggest marked differences in the use of opioids after surgery internationally; however, this has not been evaluated systematically across populations receiving similar procedures in different countries. Objective:To determine whether there are differences in the frequency, amount, and type of opioids dispensed after surgery among the United States, Canada, and Sweden. Design, Setting, and Participants:This cohort study included patients without previous opioid prescriptions aged 16 to 64 years who underwent 4 low-risk surgical procedures (ie, laparoscopic cholecystectomy, laparoscopic appendectomy, arthroscopic knee meniscectomy, and breast excision) between January 2013 and December 2015 in the United States, between July 2013 and March 2016 in Canada, and between January 2013 and December 2014 in Sweden. Data analysis was conducted in all 3 countries from July 2018 to October 2018. Main Outcomes and Measures:The main outcome was postoperative opioid prescriptions filled within 7 days after discharge; the percentage of patients who filled a prescription, the total morphine milligram equivalent (MME) dose, and type of opioid dispensed were compared. Results:The study sample consisted of 129 379 patients in the United States, 84 653 in Canada, and 9802 in Sweden. Overall, 52 427 patients (40.5%) in the United States were men, with a mean (SD) age of 45.1 (12.7) years; in Canada, 25 074 patients (29.6%) were men, with a mean (SD) age of 43.5 (13.0) years; and in Sweden, 3314 (33.8%) were men, with a mean (SD) age of 42.5 (13.0). The proportion of patients in Sweden who filled an opioid prescription within the first 7 days after discharge for any procedure was lower than patients treated in the United States and Canada (Sweden, 1086 [11.1%]; United States, 98 594 [76.2%]; Canada, 66 544 [78.6%]; P < .001). For patients who filled a prescription, the mean (SD) MME dispensed within 7 days of discharge was highest in United States (247 [145] MME vs 169 [93] MME in Canada and 197 [191] MME in Sweden). Codeine and tramadol were more commonly dispensed in Canada (codeine, 26 136 patients [39.3%]; tramadol, 12 285 patients [18.5%]) and Sweden (codeine, 170 patients [15.7%]; tramadol, 315 patients [29.0%]) than in the United States (codeine, 3210 patients [3.3%]; tramadol, 3425 patients [3.5%]). Conclusions and Relevance:The findings indicate that the United States and Canada have a 7-fold higher rate of opioid prescriptions filled in the immediate postoperative period compared with Sweden. Of the 3 countries examined, the mean dose of opioids for most surgical procedures was highest in the United States.

Dataset Information

The United States and Canada as a coupled epidemiological system: an example from hepatitis A.

Publications

The United States and Canada as a coupled epidemiological system: an example from hepatitis A.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets