Suspension of CDC flu tracking raises concern

Hospital waiting room
Hospital waiting room

US physicians, obviously, can see flu-related illness locally, but national data help them predict what might be coming soon., iStockphoto

With the influenza season approaching and the Centers for Disease Control and Prevention's (CDC's) flu surveillance program suspended by the government shutdown, the lack of national flu data is starting to cause some worries.

The CDC's weekly flu activity report, FluView, is missing today for the second week in a row. That means there's no report on where flu cases are picking up, what strains are circulating, whether they match the strains in the vaccine, and whether they are sensitive to available antiviral drugs, among other things.

CDC officials announced on Oct 1, when the shutdown began, that they would not be monitoring flu activity during the hiatus. "Due to the lapse in government funding, regular updates to the CDC Influenza web site, including the weekly FluView report and updates to guidance for clinicians, will not be possible," says a statement on the CDC's Flu Activity and Surveillance Web page.

"CDC will not be routinely analyzing surveillance data nor testing laboratory specimens submitted as part of routine surveillance. Support for outbreak investigations and response to public queries regarding influenza circulation and prevention will be limited during this time."

That doesn't mean the agency has stopped all of its flu-related efforts. CDC spokesman Tom Skinner told CIDRAP News today, "CDC continues to provide limited support for respiratory disease/influenza outbreak investigations, and emergency processing of influenza laboratory samples for potential pandemic strains, to comply with International Health Regulations [IHR]."

He added that states are continuing their routine influenza testing. But patient specimens that would normally be sent to the CDC are being diverted to three state public health laboratories, in Utah, California, and Wisconsin, for further testing, he reported.

If a novel flu virus cropped up, signaling a possible emergency, the CDC would be able to call in furloughed employees to respond in accordance with the IHR, Skinner said, adding, "We will process laboratory samples and characterize potentially pandemic unsubtypable influenza viruses."

He also said states are continuing to submit their flu data to the CDC, and the agency "will go back and analyze those once normal government operations resume."

James Nordin, MD, MPH, a pediatrician and clinical investigator at HealthPartners Institute for Education and Research in Bloomington, Minn., voiced concern about the lack of information on national flu activity and particularly on the antiviral susceptibility of circulating flu strains.

"The tracking is very useful in terms of knowing what sort of resources you're going to need for flu," as suggested by the levels of activity around the country, he said. "We'll see what's coming through our door, but with national trends from CDC surveillance, that gives us some ability to predict what's going to happen in the next week or two. Without that it puts us in a much more reactive rather than proactive position."

Nordin said an even more important issue to him is the information on antiviral sensitivity of flu strains: "I think that's the single biggest problem."

He said strains in recent years have generally been resistant to amantadine but sensitive to oseltamivir (Tamiflu), but there have been times when the opposite was the case. "For patients with chronic illness, we really need to treat them as soon as possible, and we're not going to have the idea of what's the appropriate drug," he said.

Another concern for Nordin is that a CDC-funded program to monitor the safety of vaccines for flu and other diseases has been suspended because of the shutdown. He is a site investigator for the program, called Vaccine Safety Datalink.

"We routinely do a rapid-cycle assessment with flu vaccine each week, and that's not going to happen until the government reopens," he said. "It's the primary real-time vaccine safety assessment done in the US." He added that the program has a population base of about 9.5 million, so vaccine safety problems can be detected fairly quickly.

Kristen Ehresmann, RN, MPH, director for infectious diseases at the Minnesota Department of Health in St. Paul, said the shutdown means she'll have little ability to compare flu activity in Minnesota with the national picture.

"When it comes to flu surveillance, we have the ability to do testing at the state lab, so we'll continue to be able to do that," she said. "But what were going to be lacking is we won't be able to look at what's happening nationally and compare it with what's going on in Minnesota. . . . There'll be a lack of info in terms of how to interpret the data we have."

Ehresmann added, "We have the ability to test for what are expected to be commonly circulating strains, but if we test something and find it doesn't match the reagents we have, normally we can send it to CDC. So if we have something unusual, it's going to be challenging to recognize and respond to that on the national level. We're thinking about flu because it's flu season, but certainly that could be the case for other novel viruses, like MERS-CoV [Middle East respiratory syndrome coronavirus]."

Meanwhile, a private company is stepping into the breach and trying to provide some of the national flu data that the CDC can't supply during the shutdown, according to a Wall Street Journal report today.

The newspaper said athenaResearch of Watertown, Mass., is putting out its own weekly flu reports, based on insurance claims filed by about 15,000 primary care providers in 49 states. The firm, a unit of athenahealth, a provider of electronic health records, uses "cloud-based software" to track what's going in the practices.

"We were uncomfortable with the prospect of no national surveillance," Josh Gray, vice president of athenaResearch, told the Journal. "It's going dark at a critical period when flu is starting to ramp up."

The company's latest report, released Oct 9, shows that only 4.4 out of 10,000 patients who visited providers were found to have flu last week, signaling no increase in activity yet.

See also:

CDC statement on flu surveillance

Oct 11 Wall Street Journal story

Oct 1 CIDRAP News story "Fed shutdown affects disease detection, food safety"

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