Tag Archives: influenza

Health, News

Would You Like the Real Flu or Fake Flu? Chances are Good Either Way.

So…you, not me, but everyone else we know has gotten or had the flu this winter. But which flu? As King County Health explains, there’s a big difference between a stomach “flu” and influenza. The norovirus is the most common culprit in stomach bugs (salmonella is #2) that produce vomiting and diarrhea. There is some body ache overlap, but influenza is more likely to feel like a high fever and mean cold ganged up on you.

This winter, the nation has been beset by both. A new strain is now “accounting for about 60 percent of norovirus outbreaks,” reports the Associated Press. It’s responsible for 140 different outbreaks across the U.S. since last fall.

One trait that the norovirus shares with influenza is that its spread is fueled by close quarters — King County has seen long-term care facilities report 32 outbreaks of influenza since January 1 of this year, “compared to an average of 12 total outbreaks reported per season since 2007-2008 (peak, 21).” As of mid-January 2013, state officials have confirmed 12 influenza-related deaths, the majority of cases in senior citizens.

The only good news is at this particular moment, Washington’s pertussis outbreak has subsided a bit compared to the same time last year.

You can use Google Trends to explore “stomach flu” in Washington — if you drill down, you’ll discover that Enumclaw seems particularly hard hit, so now might not be a good time to do that restaurant tour. Real flu activity remains “intense,” Google says.

Washington’s department of health concurs: their weekly update (January 6 – 12: pdf) shows a slight increase from the preceding week: 160 confirmed cases from 144. About one-quarter of the people tested (you have to have a temperature of over 100 degrees and a sore throat or cough) are confirmed with influenza. With its more dense population, western Washington leads the eastern side of the state in total cases.

There’s not much to do about the norovirus, other than to stay hydrated, and to give yourself three days after symptoms have subsided before you think about preparing food for anyone. Cleaning up after the “symptoms” is a must: use bleach and water. Once you’ve got the flu, there’s not much to do about that, either. This year’s flu shot is turning out to be about 62-percent effective, which is better than even odds.

Health, News

Nasal Spray is Tops for Flu Protection for Kids

(Image: FluMist)

The CDC’s reports show the flu widespread across much of the U.S., with the South feeling particularly feverish and congested. Here in Washington, it’s the western half the state that’s been hardest hit.

The last two weeks of 2012, as people gathered for holiday celebrations, the number of people complaining of the flu to western Washington ER doctors soared past the annual baseline percentage for such cases. That last week of 2012, a total of 20,821 people came into the ER feeling sick from something like the flu. (A little more than 22 percent of the cases were confirmed to be influenza by lab tests.)

If you haven’t caught the flu yet, you might be weighing a family trip to get a flu shot — by the way, King County has an online flu vaccine finder. Before you go, here’s some news: According to a 2011 study of studies conducted by infectious disease experts, the flu nasal sprays (or LAIVs) “consistently show highest efficacy in young children (aged 6 months to 7 years),” at 83 percent effectiveness.

That said, the sprays are known to cause wheezing in children under two years of age — FluMist has the relevant caveats on their home page. Probably you’re wondering if the live version of the flu isn’t exactly what you’re trying to avoid. The difference is that the spray version’s virus can only live in the cooler climes of your nose. It creates an immune response, but dies before it can colonize your lungs.

Adults up to 49 years of age can get a nasal spray, too, rather than a shot, but they don’t show the same immunological response to the live attenuated vaccine (LAIV) as kids do. The trivalent inactivated vaccine (TIV) that’s in a flu shot rings in at 59 percent effectiveness in adults 18 to 64. That average is misleading, in a way, since the vaccine (in the studies used, which covered flu seasons between 2004 and 2009) ranged from 16 to 76 percent effective.

“The effectiveness of the flu vaccine depends on a number of factors, including how well matched it is to the circulating virus, and the underlying age and health of the person vaccinated,” says Dr. Jeff Duchin, chief of King County Health’s Communicable Disease Control, Epidemiology & Immunization Section. But “[i]nterestingly, the CIDRAP study did not find a good correlation between antigenic match and effectiveness. In addition, the 2009 H1N1 outbreak had a very well matched vaccine yet VE was still about 59 percent.”

The variability seen in the studies, then, is something of a mystery. While the two worst years for vaccine effectiveness were indeed years when the vaccines mix of flu strains didn’t correspond to what Nature served up, in another year where the same thing happened, the vaccine was almost 70 percent effective.

“Although not perfect,” concludes Duchin, “flu vaccine is still recognized as the single most important step that we can take to decrease the risk for influenza infection, related complications, hospitalizations, and deaths.”

Health, News

Washington State’s Flu Season is Now Open

“Early start may mean bad flu season ahead,” reads the headline in the Seattle Times, but so far the news in Washington is good — that’s a national wire story. The CDC’s flu map shows the worst outbreaks occurring on the East Coast — and Alaska. Here in Washington State, the flu is rated “sporadic,” below epidemic levels and tracking closely with the rate of the past two years at this time.

Still, the turning point may come as early as four to five weeks, as it did two years ago. Levels of immunity and good behavior (i.e., not passing the flu along to the office) can make all the difference.

On that note, more good news. The majority of confirmed cases, nationally and in Washington, are of the influenza A H3 variety, and the head of the CDC, Dr. Thomas Frieden, says this year’s flu shot is protecting well against those strains of the bug. (So far, the incidence of pertussis remains low, too.) Thanks to the state’s childhood vaccine program, a shot is free for anyone under 19 years old. (This map will list the vaccination providers near you.)

There’s still time to get a jump on the prevention; Accuweather’s flu forecast for Seattle claims this cool, rainy pattern doesn’t impact flu risk.

Environment, Health, News, Science

Salmon Flu & You: Myths and Mysteries

Salmon at the Ballard Locks (Photo: MvB)

The lethal and highly infectious salmon anemia virus (ISAV) has, it’s been reported by the New York Times, “detected for the first time in wild salmon in the Pacific Northwest.” The virulent form causes damage to blood vessels and blood cells–sick fish have pale gills and hemorrhage internally.

Of 48 juvenile sockeye salmon taken from British Columbia’s River Inlet, two tested positive for ISAV. Those findings are being checked now by third parties, but the original was performed by Dr. Fred Kibenge, from the OIE reference lab for ISAV. (Kibenge’s name is on most every ISAV study you will come across.)

Simon Fraser University’s Richard Routledge, a lead author on the study with biologist Alexandra Morton, is quoted as saying the virus might have “a devastating impact” on wild and farmed salmon. To date the virus has had its most lethal results in the hot zones created by salmon farms. Specifically, salmon farms raising Atlantic salmon.

A 2006 study found, “Coho salmon were resistant to all ISAV isolates”–Pacific salmon could carry the virus, but would not display symptoms. They were a disease reservoir. (This despite a 2001 study that found Chilean farmed Coho were killed by ISAV.) That’s why this finding, in a mysteriously declining population of Pacific salmon, is so disturbing.

Nor is the activist Morton disinterested, as her blog makes clear:

…Canada has failed to maintain a line of defense against ISAV. There is no place on the Fish Health Certificate that must be signed by foreign hatcheries to report ISAV. Even when the European strain of the virus began spreading in Chile, Canada did not close the border to eggs, government did not even make it a reportable disease if it occurred on a fish farm, even though it is an internationally reportable disease.

Classified as an Orthomyxoviridae virus, ISAV’s “behavior” is compared analogically to influenza, while researchers attempt to find out how, specifically, the virus works: “Through functional studies of the coded proteins it has been established that RNA segments 5 and 6 code for a fusion protein and hemagglutinin, respectively, while two polypeptides coded by segments 7 and 8 inhibit interferon induction.”Ah.

It’s definitely a fish flu, and not something you can pick from a can of salmon mousse (unless you are an Atlantic salmon), but of course influenza-type viruses tend to mutate. When scientists examined the 2007 strain of ISAV that decimated Chilean salmon farms, they discovered that the strain had arrived in Chile about 1996. The 2007 incidence of ISAV “caused the overall production of salmon to plummet 50% and 15,000 employees to lose their jobs.”

(ISAV is not the only disease stalking salmon, of course: “Severe infection by the myxozoan parasite Ceratomyxa shasta has, in large part, been responsible for the declining numbers of juvenile K[lamath] R[iver] fall Chinook and coho salmon and subsequent impacts on later adult returns.“)

U.S. Senators Maria Cantwell (D-WA), Lisa Murkowski (R-AK), and Mark Begich (D-AK) are taking no chances on it being ISAV. The three are calling for an investigation of the potential spread of the virus: Commerce, Justice, Science (CJS) Appropriations bill (H.R. 2112), “calls on the National Aquatic Animal Health Task Force to evaluate the risk the virus could have on salmon off West Coast waters and Alaskan waters, and to develop a plan to address this emerging threat,” says a release from Cantwell’s office.

Health, News, Science

Why a Drug-Resistant Flu is Coming for You

The SunBreak’s Audrey has already made the link between Steven Soderbergh’s Contagion and the flu, and because news about the end of humanity is more relevant if it’s piggybacked on a recent film, we’re going to let the researchers at the Fred Hutchinson Cancer Center make the Contagion analogy yet again:

In the new movie Contagion, fictional health experts scramble to get ahead of a flu-like pandemic as a drug-resistant virus quickly spreads, killing millions of people within days after they contract the illness.

Although the film isn’t based entirely on reality, it’s not exactly science fiction, either.

(Okay, third time: This Thursday, 6:30 to 8:30 p.m., film-talking-guy Warren Etheredge discusses Contagion with Seattle infectious disease experts Ann Marie Kimball, MD, MPH, author of Risky Trade: Infectious Disease in the Era of Global Trade and a professor of epidemiology at the University of Washington; and David Sherman, PhD, a tuberculosis researcher at Seattle Biomed and adjunct associate professor at the UW School of Global Health. The panel will be held at the Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500.)

Dennis Chao, FHCRC researcher

Researchers Dennis Chao, Jesse D. Bloom, Beth F. Kochin, Rustom Antia, and Ira M. Longini, Jr., have published a paper on drug-resistant flu in the Royal Society journal Interface that illuminates–horrifically, if you’re inclined to see things this way–how quickly the flu has become resistant to Tamiflu, even though it shouldn’t have, given the “low overall level of the oseltamivir [i.e., Tamiflu] usage.”

We were not around for the 1918 flu epidemic, but we’re still very impressed by it, and regular readers of The SunBreak know that we like to keep close tabs on the efficacy of flu vaccines and antiviral treatments.

Luckily, we have the Fred Hutchinson Cancer Research Center nearby, where Chao, Bloom, and Longini put in time (when the last is not busy with being professor of biostatistics in the University of Florida College of Public Health and Health Professions and the UF College of Medicine and the UF Emerging Pathogens Institute).

The team studied the rise in resistance to Tamiflu between 2006 and 2009 (2009 was a banner year for flu locally), discovering that their computer models for the rise of resistance would not conform with observations unless the virus was doing something surprising:

The extreme speed with which the resistance spread in seasonal H1N1 suggests that the resistant strain had a transmission advantage in untreated hosts, and this could have arisen from genetic hitchhiking, or from the mutations responsible for resistance and compensation.

In slightly plainer English, it may come down to a single person with a doubly-mutant flu bug–one that is both Tamiflu-resistant and more contagious than usual.

Ira Longini

The models predict that it’s not a question of the larger Tamiflu-using population selecting for resistance, but of a Tamiflu-resistant mutant virus getting better, faster, stronger on its own. “If you see resistant strains in parts of the world where no one is taking antiviral drugs, that’s the smoking gun that the resistant strain must be transmitting,” Longini explains.

The hypothesis is that Tamiflu resistance somehow “hitchhiked” via other mutations for contagiousness. This mutant synergy is disturbing, given a) how big a problem drug resistance is already and b) that Tamiflu is stockpiled worldwide. As of the end of 2010, WHO had found about one-third of the flu strains it tested were resistant to Tamiflu (though to be fair, there are already concerns about how well Tamiflu works, under the best conditions).

All of which makes this a good year to get a flu shot. It can be wildly variable in effectiveness, depending on how well the mix of strains vaccinated against match up with what appears “in the wild,” but if you’ve ever bought a lottery ticket, you have no excuse for not taking these odds.