Flu season is winding down but still with us

To everything there is a season, including flu. We are now emerging from the other end of one of the more difficult flu seasons in recent years, although by no means out of the ordinary for the genre. Last time we commented, almost every state was experiencing widespread flu activity by the end of March only seven states reported widespread activity according to CDC:

States that were still reporting widespread flu the week of Mar 22 through 29 were Connecticut, Iowa, Maine, New York, North Carolina, Pennsylvania, and Vermont. Regional flu activity was reported in 27 states and local activity in 11 more.

This year's epidemic appeared to peak in mid-February, as 49 states reported widespread flu activity for 2 weeks in a row. The number of states with widespread activity has declined each week since the week of Feb 24. (CIDRAP News)

Here is the "epidemic curve" for this season:

i-e120149cf711685ff08211b5a463b6a7-flu.epi.curve.jpg

Source: CDC Flu Surveillance

But flu is still taking its toll in excess pneumonia and influenza (P&I) deaths. P&I deaths, as monitored in 122 sentinel cities in the US, is one of the main gauges of the severity of influenza. P&I deaths are seasonal, too, and the practice is to model them based on historical data. This produces an expected "band" around the seasonal average and when the P&I deaths go outside this band they are registered as "excess" P&I deaths. Excess P&I mortality is one of the measures of influenza impact. We can see that in this season's results the excess P&I mortality exceeds the mild 2005 and 2006 seasons and is almost as high as the fairly severe 2004 season and promises to be broader as well, despite the fact that it started later:

i-e5ec9a50cb45a3ebaebe641c22ec98c3-picurve13.gif

Source: CDC Flu Surveillance

As in last year's season, the earliest cases were H1N1 subtypes but this switched over to predominantly H3N2 later. Almost 10% of the H1N1 isolates showed a mutation thought to confer resistance to oseltamivir (Tamiflu). No isolates to date have shown reistance to the inhalable antiviral, zanamivir (Relenza).

If you had the flu this year, you'll remember it. It is a nasty disease. If you didn't have it and have never had it, you probably don't give it the respect it deserves. While the efficacy of the flu vaccine provokes debate in some quarters, it is quite a safe vaccine and in our opinion you are better off getting it -- by far -- than not.

Keep that in mind next season to minimize the chance of becoming a point on the epidemic curve, or worse, in the P&I mortality display.

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Reviewing the weekly CDC flu report is always a little frustrating for me because it always seems to raise more questions than it answers. In attempting to avoid influenza, the level of precaution I try to practice is what I've often described as "Howard Hughes mode". It's not something you'd want to maintain any longer than necessary. So in deciding when it's safe to stand down, what I'd most like to know is what's happening in the community I live in. Informal polling of my aquaintances and neighbors accounts for about half of what I use in estimating this, and the CDC report is the other half.

What the CDC means by "widespread activity" seems self-explanatory. "Regional" is a little tougher to nail down. It is defined as: "outbreaks of influenza [yadda yadda] in at least 2 but less than half the regions of the state". Problem: I don't know whether the "region of the state" in which I live (California) is currently seeing outbreaks. I don't even know how the state is divided into regions for this purpose. With any luck, next Friday's update will see California downgraded to "local" activity, but that won't be all that helpful either, because the report will not specify which locations are most affected. As this information clearly serves as the basis for the CDC report, it's obvious that it exists somewhere, but if it's accessible, I've never been able to find it.

Racter,Most states have some sort of influenza surveillance information on their Department of Health website, and California is no exception. It appears that they divide the state into Northern, Central and Southern regions, and post weekly numbers. The front page is here:http://www.dhs.ca.gov/dcdc/vrdl/html/FLU/Fluintro.htm From there, you can surf the links to get more info.

Thanks MoM!

I like the way the that in addition to other indicators, CISP uses number of filled prescriptions for antivirals. Interesting that the most recent CDC update covers week 13 (ending March 29), while the most recent CISP update covers week 12 (ending March 22). I usually figure the picture provided by the surveillance data lags behind actual conditions by at least a week anyway, but that also suggests that the CDC still has access to some data I haven't seen. It's still useful to know that incidence is somewhat higher in the Northern part of the state. I don't see separate figures for North, Central, and South; just North and South, so I'm not sure how that fits with the CDC definition of regional ("at least two but less than half the regions of the state" becomes mathematically possible only once the state is divided into at least five regions).

First, I am a US citizen, and I love my country, but please tell me what the hell is going on. I live in Medellin Colombia, where many are poor, and lack food. US citizens worry about getting the flu. I have no problem with that.
But your neoliberal policies in Colombia are allowing paramilitary forces to invade villages here, capture farmers and their families, take chainsaws, and cut off body parts, while the victim watches. Does that description offend you? It should.
And the stupidity of ignoring the relationship between tuberculosis and bird flu is horrible. Do you know many in 1918 that died during the pandemic of Spánish Flu were killed by an extremely dangerous mutation of TB that happened in pigs in Kansas, and then infected humans.
Go ahead and ignore reality. Don't worry about TB, expecially XDR and MDR TB, in combination with influenza, killing you. And please tell saint peter, when you get to the golden gates, that bird flu experts told you not to worry, they had everything under control.

Racter,

Please tell us more of your "Howard Hughes mode". I'm fascinated by "It's not something you'd want to maintain any longer than necessary". I too "step it up" during flu season.

A co-worker told me if he had the money he would live like H.H., because he hated germs. . . I never would have known until he told me, though now I notice some of his anti bacterial ways.

Spent time (too much time) in the hospital this past year with a family member suffering from Emphysema. It's a first for me, to spend that much time there. But I was surprised at the number of pneumonia patients there. I inquired as to the cause and and was told it was a tough flu season. Nurses were obviously not interested in discussing individual cases, but said the number of patients admitted was "higher than normal".

Revere-You have access to a lot of graphs that no one else sees unless they know where to look. WHO just called H2H on the China cases from son to father. Are there any graphics on the clusterings anywhere? I only see these counted as single cases on the WHO site, but nothing on the clusters and as I understand it thats where the meat gives way to the potatoes later on.

I cant figure out how many cases were verified clusters. My drinking buddy said that we should be concentrating on those rather than the one offs because they likely only came from the birds. If its a cluster and it goes B2H2H=> its probable, and likely in his opinion that they had a genetic make up inside of those famililal clusters that allowed it to infect them. Not proven of course just yet. Its been several years and its hard to keep up unless you have a table, or a graph that shows it somewhere. Those particular cases he said we should watch and see if they are breaching into the general population. Your thoughts?

By M. Randolph Kruger (not verified) on 07 Apr 2008 #permalink

Hi Randy, hope you are in good health as Yanky Winter inexorably winds down. I'm a wee bit jealous -- due to the ongoing violence enacted by homophobic public servants in 1997/8, no-one in Star Spangled Downunder wants to have a "drinking buddy" like me cry on their shoulder... There's a song -- George Thorogood's "I Drink Alone": well, it's 'bout a guy who should head off to an AA meeting. But, the sad sentiment is the same... In a world of "narcissistic self-absorbtion" why would cynical folk care 'bout what it feels like to be an infantalized second class citizen who reads WHO's Epidemic and Pandemic Alert and Response (EPR) in order to find out more on the Dec '07 Chinese "son to father" H2H-H5N1 case!?!

No, I'm not giving you another opportunity to engage in "Christian Tourette's Syndrome" -- eg. "homosexual abomination!" I'm just expressing the reality of my life, an adult life controlled by hateful hypocrites who yap on 'bout "individual freedoms" whilst taking perverted "controlling pleasure" in torturing people like me -- a 1968 born gay male, who enjoys watching AmericanOz musicals like Xanadu!

I digress from topic (only slightly:*), back to what you wrote, "WHO just called H2H on the China cases from son to father". I meandered thru the WHO w-site and found only this, "Avian influenza situation in China - update 5 (9 December 2007). The only mention of H2H is in Avian influenza situation in Pakistan - update 2 (3 April 2008). The Lancet online has info on the Chinese dad (who lived) and son (who died) and I'm wondering if that's what your drinkin' bud refers to, "...likely in his opinion that they had a genetic make up inside of those famililal clusters"!?! This Lancet report suggests genetic susceptibility to H5N1 infection.

The more things seemingly change, the more they stay exactly the same. A malnourished person with rotten teeth and gum disease, no access to personal hygiene facilities, hot water, etc... Unlike blue eyed First World folk, it's their innate genetic susceptibility which is the "cause" for viral infection!?! So, the sociopolitical reality of existence has no bearing on who gets hit with... Oh, I've said it before so I'll reiterate:

EffectMeasure -- Penalties for health care workers who don't show up in a pandemic? Posted on: April 2, 2008 7:01 AM, by revere

http://scienceblogs.com/effectmeasure/2008/04/penalties_for_health_care…

Reader response posting excerpts:

PFT, "You will get it sooner or later if you are immunologically predisposed to the particular strain."

Howdy, just a quick question: How does a mammal have innate protection against a transgenic pathogen which has never existed before in the history of existence?

I can understand how a mammal eg. a U.S. nutritionist would be immunologically better off than your average malnourished third worlder! I can understand the new reality -- for my Xgen, at least -- of personalized pre-emptive healthcare ie. psychoneuroimmunology. To keep your body "topped-up" with vitamins, minerals, etc... But that takes money and the extreme luck of living in [an economically] stable environment like AmericanOz!

By Jonathon Singleton (not verified) on 07 Apr 2008 #permalink

Jonathon,
Please read this:
A large part of the current bird-flu hysteria is fostered by a distrust among the lay and scientific community regarding the actual state of our knowledge regarding the bird flu or H5N1, and the killer Influenza Pandemic of 1918 that it is compared to. And this distrust is not completely unfounded. Traditionally, flu does not kill. Experts, including Peter Palese of the Mount School of Medicine in Manhattan remind us that even in 1992, millions in China already had antibodies to H5N1 meaning that they had contracted it and that their immune system had little trouble fending it off. Add to this Chinese Xinhua News Agency reports of at least six people being cured of bird flu by antibiotics, something which influenza does not respond to, and you increase this credibility gap.
  Dr. Andrew Noymer and Michel Garenne, UC Berkely demographers, reported in 2000 convincing statistics showing that undetected tuberculosis may have been the real killer in the 1918 flu epidemic. Aware of recent attempts to isolate the influenza virus on human cadavers and their specimens, Noymer and Garenne summed that:Frustratingly, these findings have not answered the question why the 1918 virus was so virulent, nor do they offer an explanation for the unusual age profile of deaths. Bird flu would certainly be diagnosed in the hospital today as Acute Respiratory Distress Syndrome (ARDS). Roger and others favorsuspecting tuberculosis in all cases of acute respiratory failure of unknown origin.

Herman,

Doesn't tuberculosis only kill the patient after months of illness.

Victoria,
Avian tuberculosis bacteria, with influenza virus attached, such as H5N1, are infecting humans. So the person is simultaneously infected by TB and perhaps H5N1, or another influenza virus. Avian tuberculosis is a vector for H5N1 infection of humans. A virus is capable of attaching to a TB bacteria, and replicating.
The type of TB that killed people in 1918 was incredibly toxic. It caused a cytokine storm, meaning the person's immune system, in a desperate attempt to kill the TB bacteria, also destroyed human organs, especially the lungs. The victim drowned in his own body fluids. Doctors were amazed when they examined the lung tissue. It was totally destroyed. And the skin color of the victim changed to black, as they coughed up blood, or had blood coming from the nose or ears. It had to be a terrible death.
Thousands die from TB yearly. And doctors fear extreme drug resistant TB and multiple drug resistant TB may cause a pandemic. There is really no cure for XDR-TB, since it resists most drugs. Doctors have to use surgery and isolation, and second line drugs that are extremely toxic.
While all eyes are fixed and bird flu, mutations of TB, resistant to most drugs, are exploding in Russian prisons, and wherever poor underfed people gather. It will soon start to kill obese brain dead Americans, and the virus H5N1 may enter the body simultaneously.
And doctors will misdiagnose this toxic brew, as massive death comes to visit the rich industrialized countries.
In 1918,some people appeared perfectly fine in the morning, and by midnight they were dead, after having been infected by this TB.

Revere.
Back in July 2007, Australia suffered a significant seasonal influenza outbreak. It was a herald for the Northern Hemisphere. I watched it then, and through the Northern Hemisphere winter. In retrospect, abit of international infomation sharing may have helped the Northern Hemisphere. Yes the flujab was not a good match, yes antiviral resistance did appear greater than usual, but there was some advanced warning.

As the viruses will soon sweep back to holiday in the tropics, before appearing in the Southern Hemisphere, I will be watching Oceania again.

Herman-You have to cite something here on this old son. Fluberculosis is what you are talking about. Flu is a virus, TB is a mycobacteria according to my drinking bud. It would be absolutely devastating if it did occur but I am not aware of anything remotely close to what you are saying. I did quite a bit of asking about merging genetics and yeah, it is possible but very unlikely.

I will tell you that in the 1890's just ahead of H1N1 that the Russians had a huge localized event of "Russian Flu". Killed thousands. Some believe that this might have been a herald wave of H1N1 and maybe, just maybe you are seeing this in Mother Russia? If not, post me up something that is from a science type pub and I'll read it. It will though be dissected like a frog in an 8th grade science class though because that would be an astounding development in the progression of H5N1.

I pulled Dr. Noymers paper,

http://paa2006.princeton.edu/download.aspx?submissionId=61257

" Tuberculosisis the nexus with the unhealthy because the lungs are attacked by both diseases. Since many in uenza deaths were among tubercular people, the post-epidemic population was healthier. The hypothesis is corroborated by a variety of data, including plummeting TB death rates in 1919 and thereafter. It is no coincidence that TB was, in that era, typically a disease of adults rather than of children or the elderly (cf. gure 2), and it was the most important cause of death among adults."

Noymer isnt saying that there was a merging of the diseases Herman unless you have something else that says that. He just indicated that it was just an exacerbating secondary or primary cause of death. If you got H1N1, you were pretty much toast. You get it with an active TB and you are toasted to an even brown all over. You simply bagged it. Least thats the way I read the paper.

Wouldnt matter anyway brother. You get H5N1 and you have anything bigger than a paper cut you are likely going to go down the path to dust or to meet your maker depending on your bent. But if you have something else let me know.

Jonny you Aussie slob, how are you. Listen if you ever make it to the States come on down, I'll go drinking with your abominable ass any day you want to head. Your sexual orientation is yours and its a sin, but really what isnt? I dont judge people too terribly harsh about this stuff. Its a definition of a situation and IMO is more of a Sodom and Gomorrah thing. If God is a forgiving one then thats the way its supposed to be. If man was made in his own image, does that mean that he has latent homosexual tendencies? Put that one up on Liberty University's blog site and see how long it lasts. Fucking A, bro come on down.

By M. Randolph Kruger (not verified) on 08 Apr 2008 #permalink

Randy
Thank you for your comments. I always enjoy reading your posts. For the moment I request you read the following:

Just as men get infected, bacteria can get infected and the small tadpole shaped viruses that do this are called bacteriophages, viruses that infect regular bacteria and mycobacteriophages, viruses that infect tuberculosis, which is a mycobacteria. Or both can be called simply phages. Bacteria reproduce asexually, so there is no variation of genes in a colony, and no way for them to exchange genetic material. Phages, the viruses which live inside bacteria such as the mycobacteria called tuberculosis, can allow exchange of this genetic material, as well as force natural selection. The way bacteriophages or phages allow gene diversity is after they insert their own genetic material into their bacterial prey's genome, they in essence highjack the manufacturing capacity of the bacteria for their own purposes, reproducing new viruses in the bacteria. However, when a virus makes copies of itself, sometimes it extracts some of the bacteria's DNA and copies that into the virus. When these viruses infect other bacteria, usually of the same class, such as from bird tuberculosis to human tuberculosis inside the pig, they add the other bacteria's genes to the new bacteria. This creates genetic diversity or mutations. Such genetic mutations can create far more virulent bacteria then either of the parent bacteria. This is what it is theorized happened in 1918 Haskell County, Kansas where genetic elements of human and avian tuberculosis combined inside hogs just prior to the pandemic of 1918.
  However, this is not all that phages instigate. If the devil where to work overtime in a plot to confound scientists in their quest for a causative agent to a serious disease of unknown origin, it is doubtful whether he could have come up with anything better than the phage. Attaching to the outer membrane of the bacteria with apparatus like a space landing gear, phages often times disrupts the cell membrane of say avian or human tuberculosis, which according to Pickett[8] causes much of these species cell-wall-deficient forms,often tiny fragments of varied shapes which easily pass through the smallest filters and therefore seem to be viral, yet as bacterial fragments aren't. Some of these shapes such as the frequently seen filamentous forms of tuberculosis mentioned by Corper[9]are similar to those attributed to Influenza by biochemist and Influenza guru Burnet[10].Burnet, the first and for a time the only virologist in Australia, even conceded that there are bacteria with viral forms in Q-fever [11] and earlier in this same article, virology as an independent science, relates that chemical studies of purified viruses show that they are composed of the same sorts of material as bacteria. He includes influenza here although refers to the fact that it probably has no DNA. (Ibid) But, according to Xalabardar, some cell-wall-deficient mycobacterial forms also are exclusively RNA.Furthermore, points out Xalabarder, such cell-wall-deficient tubercular forms are true antigens, all of which, similar to influenza, induce the production of specific antibodies detectable by complement fixation tests, yet cannot produce a positive TB skin test[12]. In time such fragments can and do regenerate to the original classical form of the germ but are infective even before doing so. If this were not enough, phages also disrupt known staining patterns whereby a pathogen such as tuberculosis, which classically stains and is thus identified by being acid-fast (does not lose its red color when acid alcohol reagent is applied), often looses this capacity when fragmented by phages into its cell-wall-deficient viral forms, resulting in either not staining acid-fast at all or doing so intermittently, at which point they are called variably acid-fast. It is little wonder then why scientists could easily mistake bacterial elements for viruses, and all because of the actions of bacterial viruses called phages on their bacterial prey."

I am not a scientist, and I invite all those with greater knowledge to comment. I of course will attempt to do further study and supply you with what you request.
I would only ask you to keep an open mind, and continue to explore this subject.

Three or four recent papers and a conference this July in London on the symbiosis theory of viruses.

Title: Viruses as symbionts
Author(s): Ryan FP
Source: SYMBIOSIS Volume: 44 Issue: 1-3 Pages: 11-21 Published: 2007

Title: Virus-host symbiosis mediated by persistence
Author(s): Villarreal LP
Source: SYMBIOSIS Volume: 44 Issue: 1-3 Pages: 1-9 Published: 2007

Title: The players in a mutualistic symbiosis: Insects, bacteria, viruses, and virulence genes
Author(s): Moran NA, Degnan PH, Santos SR, et al.
Source: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Volume: 102 Issue: 47 Pages: 16919-16926 Published: NOV 22 2005

How viruses shape the tree of life.
Luis P. Villarreal
Future Virology 2006; 1(5):587-595.

By phytosleuth (not verified) on 08 Apr 2008 #permalink

Wow! Such a lot of interesting info posted here. I don't know much 'bout bacteria (cept the stuff under my arms -- phhheeeeuugghhhhwwwww!?!) as I've focussed on virology since the late 90s, working at the metro Perth, WA, branch of the AIDS Council.

Transgenic pathogen A/H5N1 epidemiologically acts as the flu (timeframe of infection, symptoms, then rare recovery or likely death, etc), so Victoria is indeed correct to point out the temporal differences between the flu and TB. But, the probable evolutionary mechs of H5 -- horizontal gene transfer and recombination -- engage equally with bacteria, so high path TB could be evolving in a bizarre and accelerated manner like cross-species viruses? I don't know, cos I aint got the time to study that area...

Randy, well Charlton Heston would rise from the grave to spank my ass, but... I always thought movie Jesus was OTT homoerotic (including the Planet Of The Apes character who symbolically represents Jesus)!?! Yeah, I'll be sure to catch up if and when I go to Yankee-ville (correct spelling this time) -- cold brews will be my shout:*)

By Jonathon Singleton (not verified) on 08 Apr 2008 #permalink

Well if you can put genes from a lightning bug into a tobacco plant and make it light up, Herman could have something.

Bests Jonny. I consider your deal to be a cross to bear in a very unforgiving society. Shit, if you were in Iran you would be talking to C. Heston by now.

By M. Randolph Kruger (not verified) on 09 Apr 2008 #permalink

Somine,

Where are you from? Could you please write in English. Would love to read what you wrote.

victoria: "Somine" is one of many dozens of spam comments from Turkey I have to continuously clean up. It is aggravating.