Plane diverts to Edmonton with ill patient; initial tests show man had H7 flu - further testing rules it out

[Nox]

http://www.ctvnews.ca/health/plane-d...-flu-1.1344985

Helen Branswell, The Canadian Press
Published Thursday, June 27, 2013 7:17PM EDT

The Public Health Agency of Canada says an American man who ended up in an Edmonton hospital tested positive for previous infection with an H7 influenza virus.

Canada's acting chief public health officer says the man is not currently ill with flu and therefore is not contagious.

Dr. Gregory Taylor says, though, that the event is a reminder that viruses like the new H7N9 bird flu are only a plane ride away.

The blood test used to diagnose the previous infection cannot determine the neuraminadase or N component of the virus with which the man was infected.

But the infectious diseases specialist who treated him in Edmonton was on the lookout for H7N9 flu, which has infected 132 people in China this spring, killing at least 39 of them.

The man had travelled in southern China in late May, though apparently not in a part of the country where human infections with H7N9 flu were recorded.

"Could he have been infected with H7N9? Maybe. We don't know for sure," Taylor says.

But he notes Canada has been on heightened surveillance for the new virus and this case suggests the system is working.

"It's a small world and these plane rides are short," Taylor says.

The unidentified man, described as elderly, has been travelling extensively in recent weeks. Taylor says he did not know where the man was from in the United States.

He travelled to China and from there to Singapore and India.

The man became severely ill in India and apparently spent time in an intensive care unit in a hospital there. Taylor says he doesn't know what city that occurred in or what illness led to his hospitalization.

After his release from hospital, the man travelled to Cairo, where he boarded a flight bound for San Francisco. While that flight was in the air, the man became ill and lost consciousness. The plane was diverted to Edmonton.



Read more: http://www.ctvnews.ca/health/plane-d...#ixzz2XT0G2O83

[Giuseppe]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu

The time and the clinical course of this suspected H7 avian influenza case is not clear from the provided details.

For example, what is the reason behind the choice to test the patient through serology instead by PCR?

Could the patient have caught the disease in a place other than Southern China?

What is his current health condition?

[Giuseppe]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu

The patient indeed was not infected by avian flu during its last flight to Canada from Egypt.

He suffered for a diabetic coma and aspiration pneumonia, unrelated to H7, so that the article title is a bit misleading.

The serum antibody titers against H7 viruses are not stated so it is not possible to date - from data in our hands - the infection time.

[alert]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu

It would be interesting to know this man's occupation. Could he have previously been exposed to a low-path H7 virus in the US (or in India or Egypt) other than H7N9? Or was his H7N9 infection so mild as to be missed? Or was his severe illness in India H7N9 (in which case I hope there is some serious contact tracing going on there)?

This is a truly bizarre report.

[alert]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu

http://edmonton.ctvnews.ca/u-s-traveler-found-to-have-h7-by-edmonton-health-officials-first-case-reported-in-canada-1.1346667

A man, who had to be taken off a plane after it was diverted to Edmonton, has been found to have H7 antibodies in his system ? which means the man, at some point, had been exposed to the virus.

The U.S. citizen was travelling from Dubai to San Francisco, when his plane had to make an emergency landing in Edmonton.

While health officials believe he may have suffered a diabetic coma on the flight ? which was not related to the H7 flu virus. However, routine tests found antibodies for the virus in the man?s system, which means he was exposed to the virus at some point.

According to health officials, the man had spent time travelling in China, Singapore and India ? and they said he became so ill while in India that he spent some time in intensive care.

?That history was consistent, maybe he was infected with the H7N9, which is why the attending physician actually ordered the test,? Dr. Gregory Taylor, acting public health officer of the public health agency of Canada said.

That said, it?s not clear if the antibodies found in the man?s system were related to H7N9 strain that has killed 39 people, and infected more than 100 people in China.

[snip]

[alert]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu

http://www.680news.com/2013/07/02/u-s-man-treated-in-edmonton-hospital-may-not-have-had-h7-flu-test-inconclusive/

U.S. man treated in Edmonton hospital may not have had H7 flu; test ?inconclusive?
Helen Branswell, The Canadian Press Jul 2, 2013 06:07:44 PM

0ShareTORONTO ? An American man being treated in an Edmonton hospital who was suspected of having survived infection with the H7N9 virus may not have been infected with the new bird flu after all.

Though testing done at the National Microbiology Laboratory in Winnipeg showed evidence of antibodies to H7 flu in his blood, tests conducted at the U.S. Centers for Disease Control did not corroborate that finding.

The Atlanta-based CDC did not spot H7 antibodies in the man?s blood, officials of the Public Health Agency of Canada revealed on Tuesday. And an additional test which the CDC runs, called a microneutralization test, also did not find evidence of H7 antibodies.

Dr. Gregory Taylor, Canada?s acting chief public health officer, says the results are now deemed inconclusive because two labs found two different results. That can happen, Taylor said, especially with newly developed tests for new viruses.

But Dr. Judith Bosse, the deputy minister responsible for Canada?s National Microbiology Laboratory, went a bit further, suggesting the Winnipeg lab?s test may have generated a false positive result.

?Probably the initial reaction was what we call a false positive, which is the sad part about serology tests,? Bosse, assistant deputy minister for the infectious diseases prevention and control branch, said in an interview.

?And that?s why we have to run multiple (ones), is false positives do exist.?

[snip]

[alert]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu - second test comes back negative

A bit late. Should we send something to ProMED that indicates this test result is in doubt?

Published Date: 2013-07-16 12:25:10
Subject: PRO/AH/EDR> Avian influenza, human (98): Canada ex China, H7
Archive Number: 20130716.1828022

AVIAN INFLUENZA, HUMAN (98): CANADA ex CHINA, H7
************************************************
A ProMED-mail post

http://www.promedmail.org

ProMED-mail is a program of the
International Society for Infectious Diseases

http://www.isid.org

Date: 28 Jun 2013
Source: Metronews, The Canadian Press [edited]

http://metronews.ca/news/edmonton/721800/prior-case-of-h7-flu-diagnosed-in-canada/

The Public Health Agency of Canada says an American man who ended up in an Edmonton hospital tested positive for previous infection with an H7 influenza virus. Canada's acting chief public health officer says the man is not currently ill with flu and therefore is not contagious. Dr. Gregory Taylor says, though, that the event is a reminder that viruses like the new H7N9 bird flu are only a plane ride away. The blood test used to diagnose the previous infection cannot determine the neuraminadase, or N, component of the virus with which the man was infected. But the infectious diseases specialist who treated him in Edmonton was on the lookout for H7N9 flu, which has infected 132 [now 133] people in China this spring [2013], killing at least 39 of them.

The man had travelled in southern China in late May [2013], though apparently not in a part of the country where human infections with H7N9 flu were recorded. "Could he have been infected with H7N9? Maybe. We don't know for sure," Taylor says. But he notes Canada has been on heightened surveillance for the new virus, and this case suggests the system is working. The unidentified man, described as elderly, has been travelling extensively in recent weeks. Taylor says he did not know where the man was from in the United States. He travelled to China and from there to Singapore and India. The man became severely ill in India and apparently spent time in an intensive care unit in a hospital there. Taylor says he doesn't know in what city that occurred or what illness led to his hospitalization. After his release from hospital, the man travelled to the United Arab Emirates, where he boarded a flight bound for San Francisco. While that flight was in the air, the man became ill and lost consciousness. The plane was diverted to Edmonton.

Taylor says the man may have suffered a diabetic coma in flight. When he landed, quarantine officers assessed the case and determined that the man's symptoms did not indicate active influenza, Taylor says. Once the man was in hospital, he developed what appeared to be aspiration pneumonia, pneumonia caused by drawing in fluids to the lungs. An infectious diseases specialist at the hospital where he is being treated knew the man's travel history and ordered a battery of tests. The tests were negative for active viral infection. But the blood tests turned up evidence of a past infection with H7 flu.

"The reassuring thing is that the viral tests are all negative," Taylor says. "Our understanding is he is improving and hopes to go home soon." Taylor says the Public Health Agency has been liaising with the U.S. Centers for Disease Control on the case, and the U.S. agency believes it is safe for the man to return to the United States. He says the Canadian authorities are also notifying counterparts in countries where the man had travelled.

[Byline: Helen Branswell]

--
Communicated by:
ProMED-mail Rapporteur Kunihiko Iizuka

[In the absence of identification of the neuraminidase (N) component of the presumptive infectious agent, it is impossible to establish whether the patient contracted influenza during his travels in China about the time of the 1st detection of human cases of H7N9 avian influenza virus infection. The patient's convoluted travel route and his complicated medical history before arrival in Canada make it unlikely that the matter will ever be resolved unless more sensitive tests can identify the N antigen of the infecting agent. However, it demonstrates clearly how air travel has the potential to initiate pandemics. Canada may have experienced a near-miss. On the positive side, the patient seems to be recovering and the beneficiary of intensive medical treatment. - Mod.CP

[alert]

Re: Plane diverts to Edmonton with ill patient; tests show man had H7 flu - second test comes back negative

Published Date: 2013-07-16 20:17:43
Subject: PRO/AH/EDR> Avian influenza, human (99): Canada ex China, H7, NOT
Archive Number: 20130716.1828405

AVIAN INFLUENZA, HUMAN (99): CANADA ex CHINA, H7, NOT
************************************************** ***
A ProMED-mail post

http://www.promedmail.org

ProMED-mail is a program of the
International Society for Infectious Diseases

http://www.isid.org

[1]
Date: Wed 3 Jul 2013
Source: Global News, The Canadian Press [abbreviated & edited]

http://globalnews.ca/news/689430/u-s-man-treated-in-edmonton-hospital-may-not-have-had-h7-flu-test-inconclusive/

It turns out that an American man who was treated in an Edmonton hospital may not have had H7 flu after all [see: ProMED-mail report "Avian influenza, human (98): Canada ex China, H7 20130716.1828022"].

Last week the Public Health Agency of Canada revealed that an American whose plane diverted to Edmonton because he was ill had tested positive for antibodies to an H7 flu virus. The antibody test could not determine which H7 flu virus he'd been infected with, but given that he'd recently travelled in China, the suspicion was he'd been infected with the new avian influenza virus. Public Health Agency officials say confirmatory testing done at the U.S. Centers for Disease Control did not find evidence of H7N9 antibodies. Dr. Judith Bosse, assistant deputy minister for the infectious diseases prevention and control branch, says blood tests designed to detect antibodies to new viruses can be difficult to operate in the early days, when they haven't been validated. "Probably, the initial reaction was what we call a false positive, which is the sad part about serology tests," Bosse said in an interview. "And that's why we have to run multiple (ones), as false positives do exist."

She says in order to make sure a new blood test works well, a laboratory needs to test it against multiple blood samples taken from people who haven't been exposed to the virus and people who were known to have been infected and have recovered. Those latter blood samples are called convalescent sera. Only by running that kind of validation process can a lab be certain their blood test is catching true positive cases and not cross-reacting with antibodies to other viruses. If a test cross-reacts, it could generate a false positive result. Bosse says the National Microbiology Laboratory in Winnipeg is still trying to get access to convalescent sera from China to use to validate its blood test. Other countries are in the same boat, she says.

But the U.S. CDC, which has also developed a blood test for H7 antibodies, also uses another type of test, known as micro-neutralization. It is considered "fairly specific," says Bosse. "That's why we're actually ruling out that this is not a conclusive sample," she says, adding the Winnipeg laboratory doesn't use this type of test. Taylor says the Winnipeg lab is re-examining its H7N9 blood test as a result of the event.

[Byline: Helen Branswell]

--
Communicated by:
ProMED-mail
<promed@promedmail.org>

******
[2]
Date: Tue 16 Jul 20013
From: Martin Lavoie <martin.lavoie@gov.ab.ca> [edited]


I would just like to clarify that this case was under investigation at the time, but the final results have come back negative for H7N9, which were communicated in the following week or so after the 1st announcement was made. Those negative results have been jointly confirmed by both the CDC in the USA and our National Microbiology Laboratory in Canada.

I hope this helps clarify the situation about this case who was not related to H7N9.

--
Martin Lavoie, MD, FRCPC
Deputy Chief Medical Officer of Health
Office of the Chief Medical Officer of Health
Alberta Health
24th Floor, Telus Plaza North Tower
10025 Jasper Avenue NW
Edmonton, Alberta T5J 1S6
<martin.lavoie@gov.ab.ca>

[ProMED-mail and the Moderator apologise to readers for the posting of an out-of-date report, and for being unaware of subsequent developments.

We appreciate the forbearance of Alberta Health in providing information to enable us to make this correction. - Mod.CP]