Report: Superbug spreads across Alta.

Tuesday, March 13, 2007

CALGARY - Almost 500 cases of an emerging superbug strain have spread across Alberta, affecting residents in almost every corner of the province, says a new report suggesting the outbreak is more widespread than medical officials suspected.

An Alberta Health outbreak investigation found 471 cases of the virulent bacteria known as CA-MRSA, or community-associated methicillin-resistant Staphylococcus aureus, in all nine Alberta health regions.

Antibiotic-resistant Staph infections can also prove fatal: Investigators documented five individuals who died while battling the bacteria, although they couldn't determine the cause of death in two of the cases.

The CA-MRSA strain has had a foothold in Calgary since 2004. Yet before conducting the study, Alberta health officials said they hadn't received reports of cases outside Calgary - the first Canadian city to experience such an outbreak.

"We thought it was relatively isolated in one area of the province," said Dr. Gloria Keays, deputy provincial health officer.

But "it's fairly widely distributed (around Alberta) and widely distributed around Canada," she added.

MRSA has been present in hospitals for decades and in more recent years American health officials began noticing a new strain was causing infections in the community among everyone from athletes and military personnel to children in day care.

The community-associated MRSA, or CA-MRSA, first appeared in Canada three years ago among Calgary's homeless population, drug users and prison inmates. That spring, it killed a 30-year-old city man when the bug developed into pneumonia.

Since then, outbreaks have occurred in several other provinces, including British Columbia, Saskatchewan, Manitoba, and Ontario.

Typically, the strain causes grapefruit-sized abscesses on the skin, although in more serious cases it becomes pneumonia or a blood stream infection.

"Of particular concern is the potentially severe nature of the ...infection," says the report, which chronicles the emergence of the strain in Alberta between June 2005 and February 2006, although the study was only released in recent days.

The department's investigation found most cases of the strain were in Calgary and Edmonton, with 251 and 139 cases respectively.

An area in northern Alberta, known as the Northern Lights Health Region, had 21 cases, an unusually large number for its small population. The report didn't find a cause for the high rate of the bug in the area.

Other rural areas of the province had varying rates of the strain. East Central health region, for instance, had only two cases, while Peace River had four cases, all related to the local correctional centre.

Prison populations in Calgary experienced high rates of CA-MRSA, with 73 individuals infected at the Calgary Remand Centre.

The report also found five deaths in Alberta related to the infection, including the Calgary man who died of pneumonia in 2004 and two other people with bloodstream infections. Another two people who were infected with the strain died, but the cause of death wasn't clear, said the report.

Alberta Health officials may not have had reports of cases outside of Calgary prior to the study, but experts say they aren't surprised to learn infections are occurring throughout the province.

"From what we saw in the U.S., it was spreading state by state. No area seemed to be lacking some presence," says Dr. John Conly, the Calgary Health Region's antibiotic resistance officer.

The number of cases in the Calgary area, meanwhile, appears to be growing from when the outbreak began in 2004.

Local health officials now see between 30 and 60 cases of MRSA every month, typically in high-risk groups like drug users.

Calgary physicians have also seen sporadic cases in patients without such risk factors, fueling concerns the strain could spread to the general population.

"It's always a possibility," said Dr. Judy MacDonald, deputy medical officer of health for the CHR.

"That's one of reasons we want to continue to follow up cases as quickly as we can."

The Alberta Health study follows news that Canadian health facilities seeking accreditation will soon face new requirements to report rates for hospital strains of MRSA as well as another superbug.

The Canadian Council on Health Services Accreditation will begin asking hospitals and other health-care institutions for rates of MRSA and C. difficile as of next January.

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