Common Flu Strain Resistant to Popular Anti...( But other medications are available t...),Health

But other medications are available that work, CDC officials stress

THURSDAY, Jan. 8 (HealthDay News) -- The most common strain of flu this season is resistant to the popular antiviral drug Tamiflu, but government health officials said Thursday there is no reason to panic.

The fact that the flu season so far has been slow, and that other drugs work well against this particular flu virus, has health officials adopting a watchful attitude for now.

While the cause of the mutation that made the virus resistant to Tamiflu (oseltamivir) isn't known, experts suspect it was caused by the wide use of Tamiflu in other countries to treat upper respiratory infections.

There were reports last year from Europe and other countries that a certain type of flu -- H1N1 -- was resistant to oseltamivir, according to Dr. Joseph Bresee, chief of flu prevention at the U.S. Centers for Disease Control and Prevention.

This year, the CDC was on the lookout for flu resistance to Tamiflu in the United States and, sure enough, it showed up. Moreover, the proportion of the strain that is resistant has gone up from around 10 percent last year to all of the H1N1 strains this year, Bresee said.

Two weeks ago, the CDC issued new guidelines urging doctors to test suspected flu cases to see if they are influenza A or influenza B, and if they are A, whether they are H1 or H3 viruses, Bresee said.

"We didn't want to make a big deal out of this," Bresee said. "We think it's interesting. We think it's worth monitoring closely, but we are still watching. When we see more, then we will get a better sense of what the public health impact of it is. We don't have a good feel of that yet."

The resistant strain is the most common type of flu circulating in the United States right now, but the season is early and the number of cases is low, Bresee said.

As more flu cases are reported, other strains of the virus ma
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