# 2087
One of the continuing topics among flu watchers is `how many Indonesian bird flu cases are we missing due to misdiagnosis?'
Coincidentally, last night I spent perhaps an hour on a Skype conference call with some Internet news hounds, discussing this very question.
Today, we get a story out of the 13th International Congress on Infectious Diseases currently underway in Kuala Lumpur, running from June 19th to the 22nd, that gives us an inside look at the difficulties of diagnosing H5N1 infections in humans.
First the article, then some discussion.
Friday June 20, 09:10 PM
Bird flu 'misdiagnosed in Indonesia'
Some cases of human bird flu in Indonesia have been variously misdiagnosed as dengue fever and typhoid, resulting in the late administration of drugs, a leading doctor in the country said on Friday.
Indonesia has had the highest number of human H5N1 cases in the world and while mortality rates are around 60 per cent in other places, the figure is highest, at 81 per cent, in Indonesia.
Sardikin Giriputro, director of the Sulianti Saroso Infectious Disease Hospital in Indonesia, told an infectious disease conference in Kuala Lumpur that misdiagnosis and the late administration of drugs were partially responsible for the high mortality rates.
"It (H5N1) is misdiagnosed initially as dengue, bacterial pneumonia, typhoid and upper respiratory tract infection because of similar clinical features (symptoms)," Giriputro said.
Indonesia has had 135 confirmed human H5N1 cases from late 2003 to May 2008 and 110 resulted in deaths. The country reported two more confirmed cases this week, but these were not reflected in Giriputro's figures.
I don't think that any serious flu observers think that human cases of bird flu are rampant in Indonesia, or that efficient H2H (human to human) transfer is occurring there (or anywhere else, for that matter).
Something like that couldn't remain hidden for very long.
But many of us do believe the incidence of human H5N1 infection is likely higher than is being reported.
While Dr. Sardikin Giriputro in the above article is mainly talking about late diagnosis it stands to reason that some patients never get a correct diagnosis, and their deaths are attributed to some other cause.
Last month, a 16 year-old girl is confirmed to have died of bird flu in South Jakarta, but untested and uncounted is her brother, who died 10 days earlier from `Typhus'.
An older sibling was hospitalized in the days after her death, put in isolation, and on Tamiflu . . . but was never diagnosed with H5N1 either.
Of course, we've no way to know for sure if these two siblings also had H5N1, but it is more than a little suspicious.
We've heard similar stories before. And of course, there are likely many cases we simply never hear about.
The `rapid flu test' we often hear about is notoriously inaccurate, or as Dr. Giriputro puts it:
"It depends on the viral load (in samples taken from patients)," he said, adding that test results could turn out negative even if the person was infected with H5N1, simply because there was not enough virus in samples taken.
Given the difficulty in accurately diagnosing bird flu against the background din of Dengue, Typhus, and other respiratory ailments, Indonesia has distributed Tamiflu (Oseltamivir) to local clinics in areas where H5N1 has been reported before.
"When doctors see influenza-like illnesses and where there is evidence of contact with sick poultry, then they give Tamiflu (without waiting for laboratory results)," Giriputro said.
Once again, the early use of Tamiflu may be masking (and curing) H5N1 cases that are never counted. A mixed blessing, as there are fears that indiscriminate use of the antiviral could result in an increase in resistant strains of influenza viruses.
The bottom line here is the numbers of bird flu cases reported by individual countries should be viewed more like polling data than as an accurate count.
When pollsters want to know the trends in a nation of 300 million people, they will talk to 1,000 or perhaps 10,000 of them. From that representative sample they can extrapolate how things are going nationwide.
And so it goes with case counts from Indonesia, or any other country. We can watch them for `trends', upswings or downswings in activity, but we shouldn't considered them as definitive totals.
The good news right now is, whatever the true number of human cases in the world, the apparent rate of infections does not seem to be going up.
And that is good news, indeed.
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