Public health officials remain on high alert for flu-like symptoms among Canadian travellers who recently returned from Mexico, following confirmation Friday of a swine flu outbreak in that country that has killed at least 20 people in the last month.
According to Agence-France Presse, Mexican authorities say “45 deaths and 943 possible infections” are now being investigated. The cases had earlier been called severe respiratory illnesses and hadn’t been identified as human cases of swine flu.
As of Friday morning, no cases have been identified in Canada.
Canada’s National Microbiology Laboratory in Winnipeg has been involved in assisting Mexican authorities identify the flu-like sickness, which has mostly struck healthy young adults. Most of the cases are concentrated in Mexico City and others were reported in San Luis Potosi, Baja and Oaxaca.
The lab, recognized as a world leader in identifying infectious diseases, was sent samples from Mexico. It’s not clear if the test results from Winnipeg were the ones that prompted the Mexican government to confirm the cases as swine flu. Laboratories in the United States were also testing samples from Mexico.
Seven people in the United States, five in California and two in Texas, have also contracted swine flu. It’s not yet known if the strain they have, H1N1, is the same as the one in Mexico. All seven have recovered and U.S. health authorities say they are not overly concerned about the cases but are monitoring the situation.
According to the U.S. Center for Disease Control and Prevention, swine flu is a respiratory disease common in pigs that is caused by type A influenza and was first identified in 1930. Over the years, different variations of the swine flu viruses have emerged.
Swine flu viruses do not normally spread to humans, but when they do it is usually because people have had direct exposure to infected pigs. In the recent cases reported in California and Texas, none of the people had any exposure to pigs.
There have been a dozen reported cases in the United States between December 2005 and February 2009 and the virus has been known to spread from one person to another. In 1988, a 32-year-old pregnant woman became sick a few days after visiting a county fair where there was widespread illness among the pigs. She died eight days after being hospitalized.
The symptoms are similar to those of a regular flu such as fever, coughing, lack of appetite, and energy loss. Some people who have contracted the virus report runny nose, sore throat, nausea, vomiting and diarrhea.
Canadians who have returned from Mexico within the last week and are feeling sick should advise their doctor of their recent travels.
A Cornwall Ont., man who returned from the vacation hot spot with a mysterious illness in late March spent 11 nights in an Ottawa hospital’s intensive are unit before being released April 9.
Prospective travellers are being warned to be vigilant and to take precautions.
The World Health Organization is keeping a close watch on the developments in the United States and Mexico. It has identified swine influenza as a potential source of human flu pandemics. Concern and preparation for a flu pandemic have recently centred on the H5N1 strain of the bird flu. The WHO has activated its global epidemic operations centre.
