# 5114
On November 22nd, a 21-year-old woman from West Java, Indonesia was admitted to Hasan Sadikin (RSHS) hospital with serious respiratory symptoms, and was almost immediately placed on a ventilator.
The tentative diagnosis was possible H5N1, or bird flu, infection. Laboratory tests were ordered to either confirm, or rule out, the virus (see Bandung, Indonesia: Bird Flu Suspect).
Twelve days later, and after multiple laboratory tests (results undisclosed), the young woman remains on a ventilator (although somewhat improved) and doctors are still unable to say whether she has the H5N1 virus.
As we’ve discussed often in this blog, testing for the H5N1 virus has always been fraught with uncertainties.
The virus can be very difficult to detect, and in some cases, has only finally been found in biopsied lung tissue taken after the patient died.
Complicating matters, the administration of the antiviral Tamiflu can reduce viral replication enough to make detection of the virus harder.
Due to these ambiguities, it has become customary to require more than one positive (or negative) test result before diagnosis or ruling out H5N1.
Which brings us to today’s story out of Indonesia, courtesy of Shiloh on FluTrackers, that updates this woman’s condition and tells us that after 12 days and more than five laboratory tests, her diagnosis remains uncertain.
Here is Shiloh’s translation of the original article (follow the link to read the whole thing).
Saturday, December 4, 2010
Pasteur, (GM) - Despite already being treated for 12 days at room Flamboyan Hasan Sadikin Hospital (RSHS), but the status of the patient Mrs. K (21), residents of Bandung, has not been determined by the Ministry of Health of Indonesia cq Agency for Health Research and Development (Balitbangkes).
"The letter does not officially exist. But the symptoms shown by patients, it seems positive of H5N1 virus (bird flu, red)," team spokesman said the handling of bird flu and infectious disease infectious RSHS, dr. Primal Sudjana, Friday (3 / 12).
According to the Primal, allegedly leading to stronger positive for bird flu because the sample examination request more than five times. Balitbangkes usually just ask for sample tests of the suspect no more than five times.
Ny. K came in and received intensive care since 22 November. "If the result is negative, usually span of the sample examination is also much faster. Never mind many times. But, of course, to this day we still hope it's negative," he said.
The detection of the H5N1 virus isn’t an easy task, and only a limited number of laboratories around the world have been certified by the World Health Organization as capable of doing so.
Indonesia’s National Institute of Health Research and Development) NIHRD received WHO accreditation for PCR testing for the H5N1 virus a number of years ago.
But here is where things get `complicated’
In 2007 Indonesia stopped sending virus samples to laboratories outside of their country as part of an ongoing battle over legal `ownership’ of the virus.
In order to maintain accreditation, laboratories are supposed to submit virus samples (and their test results) to WHO reference laboratories on a regular basis.
While the World Health Organization obviously continues to accept laboratory findings from Indonesian laboratories, it is unclear to me (from my limited internet research) how long it has been since that lab was actually `tested’ by the WHO.
PCR testing – for which they are accredited - is just one of several laboratory tests available for the detection of the H5N1 virus.
In addition, the WHO’s testing guidelines list:
Rapid commercial tests
Immunofluorescence tests
Hemagglutination inhibition or micro-neutralization tests
Virus isolation and typing by tissue culture
As you can see, a negative PCR test doesn’t necessarily rule out H5N1. False negatives are possible for a variety of reasons (including problems with sample collection and shipping), and additional tests may be required.
Which is why Indonesia’s national laboratory must run multiple tests before making a determination about a patient’s diagnosis.
So doctors are often left waiting for days . . . even weeks . . . for test results on their suspected bird flu patients.
While not exactly reassuring, some of the above may help explain why it takes so long to get official word on the H5N1 status of suspect cases in Indonesia.
Note: It is certainly possible that some sort of recent –perhaps even backchannel - testing of Indonesia’s lab has been conducted, of which I am unaware of.
And the lack of such a test doesn’t tell us anything about Indonesia’s prowess in detecting the virus, only that no one is double checking their reliability.
One of the other concerns is, should a new clade of H5N1 appear in Indonesia, that the existing PCR tests used to detect the virus may become less sensitive.
Something that, without international sharing of the virus, we (and they) could remain unaware of for some time.
Welcome to the complicated, and potentially hazardous intersection of politics, perceived national interests, and local and global public health.
Be sure to look both ways before crossing.
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