OTTAWA — The Public Health Agency of Canada has told quarantine services to be on alert for travellers returning from Mexico after a number of severe respiratory illnesses (SRI) were reported in some regions of the country.

http://www.calgaryherald.com/Health/Canada+alert+after+respiratory+illnesses+reported+Mexico/1523180/story.html

Mexican health authorities contacted PHAC last Friday to inform them of the respiratory conditions, which were reported in the south and central areas of Mexico. The cases elevated from flu-like symptoms to severe respiratory conditions in about five days, with "a high proportion" of cases requiring assisted ventilation.

PHAC, in an April 20 report, said Mexican officials informed the Canadian health agency that the "case-fatality rate was relatively high" and that most cases involved healthy adults between the ages of 25 and 44. A number of health-care workers were also affected.

Although no cause has been confirmed, some samples were positive for influenza A and B.

PHAC said the concern for Canadians travelling from Mexico serves as a "reminder of the importance of the SRI hospital-based surveillance established after the SARS outbreak in Canada."