The H5N1 strain of influenza - often referred to as bird flu - is first known to have jumped from chickens to humans in 1997. Since 2004 it has ripped through poultry and wild bird populations across Eurasia, and had a 53% mortality rate in the first 147 people it is known to have infected. Health authorities fear this strain, or its descendent, could cause a lethal new flu pandemic in people with the potential to kill billions.
Flu has been a regular scourge of humanity for thousands of years. Flu viruses each possess a mere 10 genes encoded in RNA. All of the 16 known genetic subgroups originate in water birds, and especially in ducks.The virus is well adapted to their immune systems, and does not usually make them sick. This leaves the animals free to move around and spread the virus - just what it needs to persist.
But sometimes a bird flu virus jumps to an animal whose immune system it is not adapted to.
(hat tip fluwiki/carol@sc, and many translators, commonground, btw, dutchy, siam)
An Indonesian woman suspected of being infected with bird flu has died in the West Java city of Bandung, hospital sources there said today.
Samples from the 30-year-old woman have been sent for testing in Jakarta, said a staff member at Bandung’s Hasan Sadikin general hospital who only identified himself as Herdi.
UPDATE:
The media is saying this case is negative. That may be true, and might not be. There are many diseases
endemic to Indonesia such as typhoid, malaria, dengue...How many would cause pneumonia, MI, and require
Two Indonesian children were in critical condition at a hospital in Riau Province with doctors strongly suspecting them of having developed bird flu symptoms in the country where 84 people already died of the virus, according to local media on Monday.
The two boys age one and three are being treated in isolated rooms at the Arifin Ahmad Hospital...
"They are suffering high fever and respiratory problems," Dr. Azizman Saad with the hospital was quoted by Detikcom as saying, adding "the condition of their lungs is deteriorating, with excessive activities of liquid production."
Laboratory tests by the hospital indicated that the two patients had bird flu but further tests in Jakarta are needed for confirmation.
The Reveres of Effect Measure have a way of explaining complicated material
in a somewhat understandable manner for some of us. But, then again, even the
simplified version of this explanation is going to be a challenge for others.
What can I say? See if you can follow their commentary on the new
microfluidics technology that has produced a new untested in the field, but
fast test for H5N1. They did a decent job of making the inaccessible
just about within reach of most of us. Give it a read.
With permission from Effect Measure:
The Editors of Effect Measure are senior public health scientists and practitioners. Paul Revere was a member of the first local Board of Health in the United States (Boston, 1799). The Editors sign their posts "Revere" to recognize the public service of a professional forerunner better known for other things.
H5N1 detection in 28 minutes?
Category: Bird flu
Posted on: September 25, 2007 7:08 AM, by revere
Lots of stories on the wires... about a Nature Medicine paper describing a handheld microfluidic lab-on-a-chip to detect H5N1 inexpensively in less than 30 minutes. It was hard to understand what was involved from the news articles so I retrieved the paper (published online in advance of regular appearance in the journal hardcopy). It wasn't a particularly easy read, but here is what I was able to decipher.
This device makes use of microfluidics technologies, essentially an emerging set of techniques for manipulating very tiny volumes of material -- tiny as in millionths to billionths of a liter or even less. It is used in various so-called nanotechnologies (micropropulsion devices and other things I know nothing about) and also for the current application, a lab-on-a-chip. A lab-on-a-chip is a tiny wafer upon which several biochemical operations are performed in sequence, all in tiny volumes. Microfluidics is used to move the sample around to different locations on the wafer where various processes and analyses are carried out. The new device uses superparamagnetic particles to simultaneously isolate and then move the sample in a droplet from one tiny station to another on the chip. Paramagnetism is the property of becoming a magnet when another, external magnetic field is applied. When the external field is turned off, the material is no longer magnetic. Paramagnetism can appear when a regular (ferromagnetic) material is heated above a certain critical temperature (the Curie temperature) but superparamagnetic materials develop this property even below the Curie point. The loss of magnetism is a key element in this application because if the particles remained magnetic they would clump together. By turning off the external field, they can be separated and resuspended multiple times.
The purpose of the paramagnetism is to use another external magnetic force to move a droplet in which the particles are suspended. Thus this is a droplet-based microfluidic device, unlike many other devices where the fluid flows in tiny channels. The droplet technique allows the various processes to be changed rapidly without having to manufacture an entirely new nano device. You just move the droplet from one spot to another. This also allows the specialized moving mechanism to be separate from a disposable "bench" chip.
When operating with such tiny drops there are some unusual problems that appear. The surface area to volume ratio of tiny drops is much larger than the macro drops we are used to, and this device has several innovations or adaptations of existing technologies that get around these problems. The superparamagnetic particles can be attached to materials like silica that have biological affinities for various biological materials, including viral RNA. The particles with the RNA attached are then pulled out of the drop with a magnetic field, thus concentrating the RNA. they are then moved to another couple of drops in sequence to rinse the particle-attached RNA and moved to a droplet where thermocycling is performed to amplify segments typical of a stretch of H5N1 hemagglutinin-coding RNA... A detector is used to monitor the development of the target sequence -- if it's there. PCR at such small volumes is much faster, so the analysis time is greatly shortened. Here is the breakdown of times as given in Figure 5 of the paper: extraction and concentration of RNA on particles, 300 seconds; four washes, 40 seconds; reverse transcription, 180 seconds; hot start in thermocycler, 30 seconds; thermcylcing and melting curve analysis, 1100 seconds. This adds up to about 28 minutes. Current H5N1 tests run about four hours.
At least that's how I read the paper. If you have a subscription to Nature Medicine you will find the paper here. I will say I think this is pretty nifty. The authors claim the method is 440 per cent faster, and between 2,000 and 5,000 per cent cheaper than current methods while being just as sensitive. Could be. They haven't tested it in the field yet (it sounds like they tested it by spiking a throat swab from one of the investigators with some viral RNA because they didn't have a BSL3 lab to work with infective virus), and there is no mention of the specificity of the method, that is, a measure of its tendency to produce false positives (sensitivity measures its tendency to produce false negatives,that is, to miss cases that are really there). So we'll have to see if this device is as good as it sounds.
But it sounds good.
It sure does, but we do need to know more about the specificity. There
are already enough problems with false negatives as it is.
I give the Russians a lot of credit for being transparent about this information
unlike various other countries that I will not bother to name.
About 250,000 birds are to be culled at a poultry farm in south Russia's Krasnodar Territory following an outbreak of bird flu earlier this month, Russia's agriculture watchdog said Wednesday.
A total of 170,600 birds have been slaughtered at the Lebyazh-Chepiginskoye farm and the remaining 77,500 are due to be culled in the near future, Alexander Skorikov, the head of the animal health department at Russia's agriculture watchdog said.
September 5 about 22,000 birds were culled at the farm after a regional laboratory identified the lethal H5N1 virus in dead birds at the farm.
Krasnodar Territory is on the route taken by migrating birds in winter and is subject to a higher risk of bird flu as a result, although, according to the World Health Organization (WHO), most of the spread is through poultry and the poultry trade.
Some 6,000 chickens were culled at Sahapur village in Sadar sub-district in Bangladesh's northwestern Bogra district, 170 km of capital Dhaka Tuesday night following the detection of avian influenza virus in a poultry farm.
...Nakul Saha, owner of the poultry farm, took several dead chickens for laboratory test on suspicion that they might have died of bird flu.
The laboratory test confirmed that the chickens died of avian influenza.
Preecha Ruengchan, governor of northern Thailand's province of Phichit, called an urgent meeting with livestock officials on Thursday after birds there were found to have died without cause.
Thawatpong Paekwamdee, chief of Taphan Hin district of the province, said that test result of carcasses of chickens raised by a villager were found to have the H5N1 virus. The local authorities have killed 90 chickens within 1-km radius from the location.
Professor Jiang Gu from Beijing University, China, discusses the H5N1 research article in this week's issue. The virus was found in human tissue other than the lungs after autopsy of two avian influenza cases in China. Also discussed is the lead editorial concerning the overuse of surrogate markers in clinical trials.
Capt. Jacquelyn Polder, officer in charge of the CDC quarantine station, told Viterbo University nursing students Wednesday that a flu pandemic is inevitable, and that it will hit the country hard.
“It’s so huge, and lives will change for some time,” Polder said. “We have to get people emotionally engaged.”
Well, at least awake and aware, so that they will not be blindsided. We still
have time to do something to prepare our families.
A 21-year-old Indonesian man from West Jakarta has died of bird flu, taking the death toll from the virus to 86, a health ministry official said.
Experts are still investigating how the man contracted the virus, which is most commonly spread to humans through contact with sick fowl, Tini Suryanti, spokesman of the Jakarta health office, said.
"We don't know how he could have come in contact with sick chicken, since backyard poultry has long been banned by the city government," Suryanti said.
Right, no chickens allowed in Jakarta. It's a mystery...
Overall, Indonesia has now recorded 107 confirmed human H5N1 cases with 86 fatalities. The case fatality rate now stands at 80.37%. Up to today, DKI Jakarta has recorded 26 bird flu positive cases with 23 fatalities.
The Jakarta CFR is 88.4%, even worse than the national average. Other reports indicate that the source of the young man's infection is unclear because his neighbourhood has been cleared of backyard poultry. Reports also suggest that the week's delay in his being treated contributed to his death.
The Jakarta Post took its time reporting on the 86th flu death in Indonesia, but now it's got the story with some illuminating (and depressing) details: West Jakarta shop attendant latest bird flu victim.
indigo girl
5,173 Posts
Indonesia
This woman was just 30 years old, the media is saying that she
was possibly infected by her pet bird that had just died recently.
The English speaking media reports are leaving out quite a bit of
this very sad story. Translations are saying that five chickens had
died that she may have been exposed to. She was seven
months pregnant. Her husband, who is a HCW also had mild symptoms.
She was admitted at to the hospital with bird flu s/s as well as
pneumonia, and required intubation. They aborted her baby to try and save her.
At some point, the mother had an acute MI, and died also. Her initial tests have come back
negative for avian flu, but that is not so unusual. The Tamiflu may be responsible for a negative
result and/or changes in the virus that had not been compensated for with an updated PCR probe
or primer could also be responsible. There have been other cases like this, where nailing down a
diagnosis was only possible after autopsy. But, this is Indonesia, and no autopsy will ever be done.
At any rate, they were treating her for bird flu, and were not able to save her.
They are sending some of the viral samples to Hong Kong as well as to Jakarta
to confirm a diagnosis of H5N1 infection.
http://www.thewest.com.au/default.aspx?MenuID=77&ContentID=41236
(hat tip fluwiki/carol@sc, and many translators, commonground, btw, dutchy, siam)
UPDATE:
The media is saying this case is negative. That may be true, and might not be. There are many diseases
endemic to Indonesia such as typhoid, malaria, dengue...How many would cause pneumonia, MI, and require
intubation? You have to wonder.