Some patients originally thought to have a mysterious illness after testing negative for the flu, have now been diagnosed with the H1N1 virus.
From September 29 to December 7 of this year, 140 laboratories in the United States tested more than 3,800 people for influenza A virus. The Centers for Disease Control and Prevention reports that 90 percent of those tested positive for H1N1.
So why did the flu tests not pick it up?
"Interestingly, most of the regular test that you do for influenza, it's showing negative and that's the problem. This test does not have really good sensitivity," said Dr. Shabaz Ahmad, an infectious disease expert at Good Shepherd Medical Center in Longview.
Dr. Ahmad said this is not the first time a flu test has failed.
"What I'm finding is that it is not really sensitive for H1N1 somehow," Dr. Ahmad said.
"I have even a few cases where their tests were twice negative, so we have to do specific testing," Dr. Ahmad said.
So why do doctors not start with those tests that have more specific results?
"Most of the time it is not cost effective to do a PCR test at the get go, most of the time we do the regular testing," Dr. Ahmad said.
In fact, Dr. Ahmad believes the mysterious illnesses in Montgomery County may be still be attributed to the flu, despite the negatives results.
"The mysterious kind of deaths coming, like influenza-like illness with mysterious death, and the test is negative for flu and you think, 'Oh, there's no flu," but still flu could be hiding there and you need to do specific testing to find out," Dr. Ahmad said.
"There is nothing mysterious. This is something vaccine preventable disease," Dr. Ahmad said.
And he said the sooner you can get the flu shot, the better.
"What we are seeing in the hospitals and mysterious death, this is basically the iceberg," Dr. Ahmad said.
The peak of flu season is typically in January or February.
According to Centers for Disease Control and Prevention, the flu is already widespread in Texas. They are also reporting a high number of influenza-like illnesses. Dr. Ahmad said even if you have had the flu, the vaccine can help prevent you from catching another strain.
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