Posted on 08/30/2007 11:05:19 AM PDT by ex-Texan
In the first systematic, statistical analysis of its kind, infectious-disease-modeling experts at Fred Hutchinson Cancer Research Center confirm that the avian influenza A (H5N1) virus in 2006 spread between a small number of people within a family in Indonesia. The findings, by biostatistician Ira M. Longini Jr., Ph.D., and colleagues, will be published inthe journal Emerging Infectious Diseases.
Co-authors on the paper were biostatisticians M. Elizabeth (Betz) Halloran, M.D., D.Sc., and Yang Yang, Ph.D.; and epidemiologist Jonathan Sugimoto, M.H.S., a pre-doctoral research associate. All are within the Hutchinson Center's Public Health Sciences Division and Vaccine and Infectious Disease Institute.
The researchers based their findings on a cluster of eight flu cases within an extended family in northern Sumatra. Using a computerized disease-transmission model that took into account the number of infected cases, the number of people potentially exposed, the viral-incubation period and other parameters, the researchers produced the first statistical confirmation of humans contracting the disease from each other rather than from infected birds.
The cluster contained a chain of infection that involved a 10-year-old boy who probably caught the virus from his 37-year-old aunt, who had been exposed to dead poultry and chicken feces, the presumed source of infection. The boy then probably passed the virus to his father. The possibility that the boy infected his father was supported by genetic sequencing data. Other person-to-person transmissions in the cluster are backed up with statistical data. All but one of the flu victims died, and all had had sustained close contact with other ill family members prior to getting sick — a factor considered crucial for transmission of this particular flu strain.
In an attempt to contain the spread of the virus, the local health authorities eventually placed more than 50 surviving relatives and close contacts under voluntary quarantine and all, except for pregnant women and infants, received antiviral medication as a precaution.
"The containment strategy was implemented late in the game, so it could have been just luck that the virus burned out," Longini said. "It went two generations and then just stopped, but it could have gotten out of control. The world really may have dodged a bullet with that one, and the next time we might not be so lucky," he said.
Should a strain of avian flu acquire the ability to cause sustained human-to-human transmission, the results could be catastrophic, Longini said. "If not contained, the outbreak could spread worldwide through the global transportation network faster than the appropriate vaccine supply could be made available. That's why it's so important to ascertain whether human-to-human transmission is happening as well as the virulence of the strain." The researchers estimated the secondary-attack rate of the virus in Indonesia — the risk of one infected person passing it to another — to be 29 percent, a level of infectiousness similar to statistical estimates for seasonal influenza A in the United States.
The researchers also aimed their statistical transmission-assessment technology at another large avian-flu cluster in eastern Turkey that in 2006 infected eight people, four of whom died. In this case, the researchers did not find statistical evidence of human-to-human transmission, most likely due to a lack of sufficient data. "There probably was person-to-person spread there as well but we couldn't get all the information we needed for the analysis," Yang said.
The methods and software used in this research led to the development of a software application called TranStat, which will allow first responders to enter, store and perform real-time analysis of data from infectious-disease outbreaks. This tool soon will be available online free of charge via MIDAS, the Models of Infectious Disease Agent Study, which is supported by the National Institute of General Medical Sciences.
"We know the key to preventing a pandemic is early detection, containment and mitigation with antiviral therapy and this tool will enable those on the front lines, such as physicians, epidemiologists and other public-health officials, to carry that out efficiently," Halloran said. "The manuals on how to collect the necessary data are decades old. They are very outdated and incomplete. Often people on the front lines don't know what to do; they don't collect the correct data to assess whether transmission is occurring. TranStat will prompt people to gather precisely the data that needs to be collected to better understand and contain any infectious-disease spread, not just the avian flu," Sugimoto said.
If a smoldering disease cluster does flame out of control, the software also could be used to estimate the important characteristics of the virus — such as its transmissibility, secondary-attack rate and reproductive number — which would give public-health officials a better chance at slowing its spread until a vaccine or other effective control measures could be implemented.
Yang and colleagues recently described the basis for the statistical methods used in the research in The Annals of Applied Statistics.
The study was funded and supported by the National Institute of General Medical Sciences MIDAS network and the National Institute of Allergy and Infectious Diseases.
Longini and Halloran also are professors of biostatistics and Sugimoto is a pre-doctoral student in the School of Public Health and Community Medicine at the University of Washington.
References: Emerging Infectious Diseases paper, "Detecting human-to-human transmission of avian influenza A (H5N1)", September 1, print edition. This journal is published by the CDC.
The Annals of Applied Statistics paper, "A resampling-based test to detect person-to-person transmission of infectious disease" (2007, Vol. 1, No. 1, 211-228)
Note: This story has been adapted from a news release issued by Fred Hutchinson Cancer Research Center.
Excerpt:
The Security and Prosperity Partnership of North America summit in Canada released a plan that establishes U.N. law along with regulations by the World Trade Organization and World Health Organization as supreme over U.S. law during a pandemic and sets the stage for militarizing the management of continental health emergencies. * * *At the same time, the U.S. Northern Command, or NORTHCOM, has created a webpage dedicated to avian flu and has been running exercises in preparation for the possible use of U.S. military forces in a continental domestic emergency involving avian flu or pandemic influenza.
With virtually no media attention, in 2005 President Bush shifted U.S. policy on avian flu and pandemic influenza, placing the country under international guidelines not specifically determined by domestic agencies. * * * Source Here
In the meantime, our national borders stand wide open in a time of war. Thousands of foreign covert agents may have walked into the U.S. . . . Disguised as Mexicans.
"That is why the president did not seek a formal declaration of war against Afghanistan and Iraq," said Jerome R. Corsi. Last night on Coast-to-Coast AM seven million people heard him being interviewed. He carefully explained that federal law requires our borders to be locked down. Under a declared war. Oh, well. Nothing I can do anyway.
The 'Three Amigos' have acted. In a national heath emergency, the blue helmets will be in control.
* Ping* ! the usual list, please.
Unbelievable! How can ANYONE be so stupid as to put ANYTHING under UN control? Bush needs to go. He has harmed America/Americans in too many ways, and it’s going to affect our children and grand children for generations to come!
That said, bring IT ON!!! I'm not gonna slow down for any stupid bird flu. I'm not even gonna take a day off, I save those for when I'm really hungover.
Owl_Eagle
If what I just wrote made you sad or angry,
it was probably just a joke.
http://news.yahoo.com/s/koco/20070823/lo_koco/13961495
18 Oklahomans Diagnosed With West Nile
Should a strain of avian flu acquire the ability to cause sustained human-to-human transmission, the results could be catastrophic, Longini said. "If not contained, the outbreak could spread worldwide through the global transportation network faster than the appropriate vaccine supply could be made available.
Yeah, we dodged a bullet. That bit about "appropriate vaccine supply" is a bunch of crap - we get pretty lucky there, as well.
From Wikipedia on "Flu Vaccine": "Each year the influenza virus changes and different strains become dominant. Due to the high mutability of the virus a particular vaccine formulation usually only works for about a year. The World Health Organization co-ordinates the contents of the vaccine each year to contain the most likely strains of the virus to attack the next year."
Good luck if the virus mutates and you're exposed - then you are literally on your own...either your immune system works quickly enough, or the virus overwhelms you and kills you. This is why so many old folks and little kids die of the flu.
This is what makes me so thrilled beyond belief that we have essentially open borders (esp. to our south, 150 miles to MY south), and little or no screening of legal immigrants or tourists for disease. Can you imagine if some jihadist Indonesian Moslem gets a version of this disease that doesn't burn out, and flies to a large city on a crowded plane!!! Say goodbye to a large part of the planet's population.
Spreading the diseases that Americans are unwilling to spread.
http://news.google.com/news?hl=en&ned=us&q=west+nile+%2B+Oregon&btnG=Search+News
99% of the people who ‘get’ WNV never know it. I expect I’ve had it a number of times. It came through here a few years back and it was all the worry...a lot of birds died and were collected by health dept officials, mapped and etc. The local bird population has sprung back and are doing well. A couple of people a year die of WNV (Alabama) here now.
I’m in Eastern WA, plenty of skeeters here, last night I found 3 dead birds, & a die’n bat... not sure WTH is going on here...
The virus overwhelms you but it does not kill you. You end up killing yourself. You immune system kills you.
Point noted. Nonetheless, you are dead.
You are right - I was just picking nits. That was one of the more interesting things I learned. Not trying to be a wiseguy!
Not a very good survival rate.
I know what you mean (to steal a line I saw somewhere).
I blame Bush.
That EBOLA cleared up yet?
Are the song birds vanishing or being found dead? Song birds are large consumers of seed. The seeds have been being coated with imidacloprid. Imidacloprid affects orientation flights, foraging of bees. It would make sense to me that if that pesticide is affecting a honey bee’s flight patterns and cause disorientation, that it would also affect a song birds.
“Imidacloprid was a partial nicotinic agonist, since it elicited only 36% of ACh-induced currents and competitively blocked 64% of the peak ACh-induced currents. GABA-induced currents were partially blocked when imidacloprid was coapplied and this block was independent upon activation of nAChRs. Our results identify the honeybee nAChR as a target of imidacloprid and an imidacloprid-induced inhibition of the insect GABA receptor.”
nAChR = nicotinic acetylcholine receptors
Nicotine enhances cognitive functions, such as learning, memory, and retention through activation of brain nicotinic acetylcholine receptors (nAChRs).
The most common nicotinic receptors found in the brain are the low affinity a 7-nAChR and the high affinity a 4b2-nAChR. a 7.
***Imidacloprid, which is being sprayed as an insecticide, it is an agnostic. An agnostic is used to affect the addictive properties and some of the side-effects of nicotine.***
Hazards of imidacloprid seed coating - affects orientation flights, foraging bees
http://www.univ-tours.fr/irbi/UIEIS/Theses-DEA/Lefebvre-these.pdf
Also:
Effects of sub-lethal imidacloprid doses on the
homing rate and foraging activity of honey bees
Treated honey bees also showed anomalous
flying behaviour: they often fell in the grass and their
flight direction was not towards the hive. Treated bees
seemed to be disoriented, and that could be the cause of
their disappearance.
Ping!
That EBOLA cleared up yet?
The AIDS was just a 24 hour case and cleared up with bed rest and a couple of aspirin. The Ebola did lead to the Dr. having to amputate my left arm, but I think it's beginning to grow back.
Owl_Eagle
If what I just wrote made you sad or angry,
it was probably just a joke.
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