The Centers for Disease Control and Prevention on Friday sent a new alert to doctors, advising prompt use of Tamiflu and other antivirals for hospitalized flu patients and those at higher risk for complications like pneumonia.
CDC officials say a nasty strain of flu is going around that is more dangerous to elderly people and very young children. What's more, officials think the flu vaccine doesn't work well against this particular virus. So "it's more important than usual" that doctors treat certain patients with Tamiflu or other antiviral medications, CDC Director Dr. Tom Frieden said at a press conference Friday.
CDC officials said flu was reported to be widespread in 46 states last week, up from 43 the week before. But there was a small drop in states reporting high numbers of flu-related doctor's office visits. That's one sign that for some areas, the worst stretch of the current flu season may be ending.
Flu seasons tend to last about 13 weeks, and CDC data suggests the nation is about seven weeks in, Frieden said. "It seems we're right in the middle of flu season," he said.
However, while flu may be ebbing in some states, it's increasing in others, and it's not clear whether flu has peaked overall, health officials said.
CDC research suggests doctors prescribe antivirals to one in five high-risk flu patients. CDC officials say the number should be higher.
When given promptly — within two days of the beginning of flu symptoms — they can shorten the amount of time someone is sick with the flu, a number of studies have found. The drugs also can prevent patients from becoming sick enough to end up in a hospital intensive care unit — or worse, Frieden said.
"Antiviral flu medicines save lives," he said.
The CDC sent an advisory to physicians last month, warning them this could be a potentially bad flu season and encouraging prompt treatment with antivirals. CDC officials said doctors should not wait for test results confirming the flu if they are dealing with an elderly patient, someone who is very sick from the flu, or someone with pre-existing conditions like asthma, diabetes and heart disease.
The CDC sent a second alert to doctors Friday that repeated earlier recommendations and noted a new antiviral was approved by the U.S. Food and Drug Administration last month. It's called Rapivab, and is an infusion that can be given to sick patients who aren't able to take Tamiflu pills or another, inhalable antiviral medicine called Relenza.
Doctors have been cautious about prescribing antiviral medicines for a number of reasons, CDC officials say. Some want a lab result confirming flu before they prescribe a flu drug. In cases in which patients delayed seeking treatment, doctors may worry the patients are already be too far into the illness for the drugs to do much good.
And there also is uncertainty about the drugs' effectiveness in reducing hospitalizations and complications.
Last year, a respected international network of researchers — the Cochrane Collaboration — published a review of past studies on the medications, and found there was no good evidence to support claims that Tamiflu reduces flu complications or flu-related hospitalizations. At best, it shortens flu symptoms by half a day, the Cochrane report said.
The CDC shouldn't be promoting antivirals unless there is strong proof they prevent hospitalizations and key complications, said one of the Cochrane study's authors, Peter Doshi, in an interview Friday. He is an assistant professor at the University of Maryland School of Pharmacy, and an associate editor of BMJ — the British medical journal in which the study was published.
CDC officials say the Cochrane review had limitations; for example, Cochrane looked at high-quality studies but none that included hospitalized patients. CDC officials say the agency is giving greater weight to observational studies, which are considered less rigorous than the research Cochrane focused on, but which offered a look at what happened in hospitalized patients. And that research did find a benefit.
Also, there aren't really other options: Against flu, antiviral medicines are what's left in the medical arsenal when the vaccine doesn't work, experts say.
CDC flu update: http://www.cdc.gov/flu/weekly/Suggest a correction