Via The Calgary Herald, a fascinating report by Jamie Komarnicki: Medical sleuthing required in avian flu diagnosis. Excerpt:
The day after arriving in Alberta, she went to an emergency department — health officials won’t say where — but her symptoms were mild and she wasn’t admitted, Talbot said, noting that’s not unusual in cases where patients aren’t seriously ill.
Four days later, with her condition worsening, the woman went back in the same ER and was admitted to hospital.
By Jan. 3, she was moved to the ICU. She died later that day.
The unusual nature of the case set off a series of extra steps as staff worked to determine what had happened.
Her cause of death was diagnosed as meningoencephalitis, a type of inflammation of the brain — and also one of the ways that H5N1 patients die.
That’s when staff first contemplated they might be dealing with an international case of avian influenza.
“When she expired, people in the hospital were concerned about it being a serious illness associated with travel to China, so public health was notified that this was a case that might be a case of avian influenza,” Talbot said.
Health officials weren’t convinced bird flu was the biggest threat, especially when it was determined the woman hadn’t been to farms, poultry markets, or other high risk areas in Beijing.
But they decided to start protocols for the disease, until lab results ruled it out.
Public health officials began connecting with anyone who had been in contact with the victim, including the two people who accompanied her on the trip. In the hospital, infection control used standard protocols to identify staff and patients who might have been in close contact.
At the time, the measures were “considered overkill,” Talbot said, but with even the slightest possibility of a bird flu diagnosis, they decided it was worth it.
Officials in Alberta’s provincial laboratory performed tests through the weekend as they zeroed in on a diagnosis.
Early tests determined the woman had a strain of influenza.
With Alberta’s flu season in full swing, the next step involved ruling out the seasonal strains circulating, including H1N1, said Graham Tipples, medical director of the provincial lab for public health.
By Sunday, the provincial lab reported back that the woman had influenza A, but not the seasonal strains. That meant whatever she had likely came from somewhere else.
That’s when it was time to update federal officials, said Talbot.
On Monday, the provincial lab did more sophisticated testing.
“It showed that very definitively that it was h5, and that it was found in multiple specimens, including those taken from the cerebral spinal fluid, so that would indicate virus in the brain,” said Talbot.
“They were going the extra mile on this because they knew there would be questions on whether it would be a real positive because it would be the first case.”
The material was also sent to the national laboratory in Winnipeg for further analysis.
By Tuesday, a conclusion was reached: H5N1.
I'm trying to put myself in the shoes of the healthcare workers involved: How worried they must have been as the evidence pointed toward H5N1, how relieved they must have been to see their suspicions confirmed—and how sad they must have been that they sent the woman home when she first went to emergency.