Canada monitoring as number of H7N9 bird flu cases mount
TORONTO – February 4th, 2014 – The number of H7N9 bird flu infections continues to climb rapidly in China.
The Public Health Agency of Canada’s director general for immunization and respiratory infectious diseases said Canada is monitoring the situation in China, and continues work on an update of the national pandemic preparedness plan that was begun in the aftermath of the 2009 H1N1 pandemic.
“We’re very interested and watching very carefully what is going on in China,” Dr. John Spika said Monday in an interview.
“But the bottom line is that until the virus demonstrates some ability to more efficiently spread from person to person it remains something that we’re very interested in, watching carefully but still consider to be a low risk.”
Since the new H7N9 virus emerged last spring, there have been about 277 cases diagnosed; 63 of the infections have been fatal. After several months with no infections over the summer, new cases began to pop up in the fall as temperatures went down and conditions for the spread of influenza viruses improved. Since then, there have been 142 new cases, and 18 deaths, according to the United States Centers for Disease Control.
Canada has not asked its pandemic vaccine suppliers to make and test H7N9 vaccine, opting instead to wait for the results of clinical trials being done in the U.S.
The U.S. Biomedical Advanced Research and Development Authority — BARDA — has funded trials to test how much vaccine each person would need to gain protection against H7N9, and whether a boosting compound called an adjuvant would be needed to stretch supplies during a pandemic.
Past studies of H7 flu viruses have shown they are poorly immunogenic; without an adjuvant, even large doses produced poor results.
The U.S.-funded studies of H7N9 vaccine have confirmed that two doses per person would be needed to get a protective response, and that an adjuvant would be needed.
The U.S. has decided to stockpile H7N9 vaccine, though it will not reveal how many doses it plans to have on hand. Spika said to this point there has been no decision taken on whether Canada should add H7N9 vaccine to a national stockpile, which already includes some H5N1 vaccine.