Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Aug 18:15:341.
doi: 10.1186/s12879-015-1039-0.

Global travel patterns and risk of measles in Ontario and Quebec, Canada: 2007-2011

Sarah E Wilson  1   2 , Kamran Khan  3   4   5 , Vladimir Gilca  6   7 , Jennifer Miniota  8 , Shelley L Deeks  9   10 , Gillian Lim  11 , Rose Eckhardt  12 , Shelly Bolotin  13 , Natasha S Crowcroft  14   15   16
Affiliations

Global travel patterns and risk of measles in Ontario and Quebec, Canada: 2007-2011

Sarah E Wilson et al. BMC Infect Dis. .

Abstract

Background: In 2011 the largest measles outbreak in North America in a decade occurred in Quebec, Canada with over 700 cases. In contrast, measles activity in neighbouring province Ontario remained low (8 cases). Our objective was to determine the extent to which the difference could be explained by differing travel patterns.

Methods: We explored the relationship between measles cases over 2007-2011, by importation classification, in Quebec and Ontario in relation to global travel patterns to each province using an ecological approach. Global measles exposure was estimated by multiplying the monthly traveler volume for each country of origin into Quebec or Ontario by the yearly measles incidence rate for the corresponding country. Visual inspection of temporal figures and calculation of Pearson correlation coefficients were performed.

Results: Global measles exposure was similar in Ontario and Quebec. In Quebec, there was a nearly perfectly linear relationship between annual measles cases and its global measles exposure index over 2007-2011 (r = 0.99, p = 0.001). In contrast, there was a non-significant association in Ontario. The 2011 rise in Quebec's index was largely driven by a dramatic increase in measles activity in France the same year.

Conclusions: Global measles activity was associated with measles epidemiology in Quebec. Global measles exposure risk is higher in Ontario than Quebec. Differences in measles epidemiology between Ontario and Quebec from 2007-2011 are not explained by greater exposure in Quebec. A combination of alternative factors may be responsible, including differences in population susceptibility.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
a Global Risk of Measles Importation into Ontario, Canada, 2011. b Global Risk of Measles Importation into Quebec, Canada, 2011. Data Source: WHO/World Bank, 2011; IATA, 2011
Fig. 2
Fig. 2
a Ontario measles cases (importations and unknown source) and global measles exposure index values, 2007–2011. b Quebec measles cases (importations and unknown source) and global measles exposure index values, 2007–2011
Fig. 3
Fig. 3
a Measles exposure index for Quebec by source country of arriving travelers, 2007–2011. b Measles exposure index for Ontario by source country of arriving travelers, 2007–2011
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Meeting on Vaccine-preventable Diseases of the Pan American Health Organization: Final report of the XIX Technical Advisory Group [TAG]. Argentina; 2011. Available at: www.paho.org/immunization/toolkit/resources/tech-recommendations/TAG-201....
    1. Public Health Agency of Canada. Elimination of measles, rubella and congenital rubella syndrome in Canada. Documentation and verification report: Public Health Agency of Canada, Ottawa. December; 2011.
    1. Papania MJ, Wallace GS, Rota PA, Icenogle JP, Fiebelkorn AP, Armstrong GL, et al. Elimination of endemic measles, rubella, and congenital rubella syndrome from the Western Hemisphere: The US experience. JAMA Pediatr 2013, doi:10.1001/jamapediatrics.2013.4342. - PubMed
    1. Pan American Health Organization. Plan of action documentation and verification of measles, rubella, and congenital rubella syndrome elimination in the Region of the Americas. Technical Document. December; 2010. www.paho.org/hq/index.php?option=com_docman&task=doc_download&gid=16739. - PubMed
    1. An Advisory Committee Statement: Measles and Rubella Elimination Working Group Guidelines for the prevention and control of measles outbreaks in Canada. CCDR. 2013;39(3):1–52. - PMC - PubMed

Publication types

Substances