“It’s not a food safety issue.”
“It’s not a food safety issue.”
– Dr. Lynn Bates, Cfia
Canada’s largest anaplasmosis outbreak in more than a quarter-century continues to spread in southeastern Manitoba.
Eleven infected cattle herds have been found in a hot spot within the Rural Municipality of Stuartburn near the Canada-U. S. border. Another infected herd is in the neighbouring municipality of La Broquerie.
The cases were identified as part of a Canadian Food Inspection Agency investigation going back to October 2009. So far, 4,510 cattle in the region have been tested in the 12 infected herds, with 193 registering positive for anaplasmosis, CFIA reported last week.
Eight cases have been reported since the beginning of 2010, five of them in February alone, according to CFIA’s website.
CFIA has been testing for anaplasmosis in southeastern Manitoba since December 2008, when eight positive herds were detected in the rural municipalities of Lac du Bonnet and Alexander. Seventeen hundred cattle were tested; 345 registered positive.
The Lac du BonnetAlexander cases came to light during routine CFIA serological disease surveillance. The Stuartburn cases emerged after a local veterinarian notified the agency that several cattle in one herd had died and others showed clinical
signs of anaplasmosis, said Dr. Lynn Bates, a CFIA veterinary program officer in Winnipeg.
Altogether, approximately 10,000 cattle in 20 herds have been tested and 538 were positive, Bates said.
Animals testing positive for anaplasmosis are slaughtered for their meat. Producers are compensated at market value up to a certain limit.
“It’s not a food safety issue. There’s no human health risk,” Bates said.
She said CFIA and the province are planning producer meetings in mid-April to discuss on-farm disease prevention.
Some producers are shocked to learn their infected animals must be slaughtered, said Don Winnicky, the Manitoba Cattle Producers Association director for the southeast region.
“A few guys are saying the genetics in their cow herds have been there for 50, 60 years. They’re scared they’re going to lose the genetics in their herds,” said Winnicky, a Piney producer.
This is the largest outbreak of anaplasmosis in Canada since 1983, when the disease was detected on a ranch in southwestern Saskatchewan.
Manitoba’s last recorded case of anaplasmosis occurred near Marchand in 1968.
Bates said only the 1983 and 1968 incidents are considered true outbreaks. Limited outbreaks happened in Quebec (1979), Ontario (1996) and Saskatchewan (a 2000 case involving bison).
In a separate incident, anaplasmosis was detected last summer in the British Columbia interior. Cattle herds in four locations remain under quarantine, according to CFIA.
Anaplasmosis is a blood-borne disease caused by a parasitic micro-organism and transmitted by biting insects (or vectors). It can be spread within a herd through contaminated hypodermic needles and sometimes by maternal transmission (cow to calf ).
The source of the infections is uncertain. Bates said certain ticks known to transmit the disease can overwinter in Manitoba.
However, a more likely source is infected cattle imported from the United States.
Canada used to require anaplasmosis testing of live U. S. cattle imports during the vector season. However, since 2004, new rules have allowed feeder cattle from 39 U. S. states considered low risk for the disease into Canada without testing.
CFIA protocol requires such cattle to be fed out and sold directly to slaughter. However, it’s suspected some producers may have mingled imported animals with their own.
“We have some indications there were in fact animals that were imported and protocol was not followed,” said Ray Armbruster, who chairs the MCPA animal health committee. “There’s been instances where we’ve been told that has happened.”
Dr. Jim Clark, CFIA’s national foreign animal disease manager in Ottawa, said the agency takes action if it learns the protocol is being violated.
Clark said CFIA considers existing import protocols and disease surveillance programs adequate to guard against foreign animal diseases in Canada.
However, the agency plans to increase the frequency of its periodic disease surveillance, he said.
CFIA conducts surveillance for cattle diseases every three to five years, taking 15,000 blood samples at slaughterhouses Canada-wide. [email protected]