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.
The 24-year-old man, surnamed Lu, developed fever, chills and other symptoms on November 24 and was hospitalized on November 27 after being diagnosed "lower left pneumonia". Lu's illness deteriorated in the hospital and died on Sunday.
A respiratory tract sample examination by Jiangsu Provincial Disease Control and Prevention Center on Saturday showed the man's avian flu virus nucleic acid was H5 positive and N1 positive.
However, the man had no contact with dead poultry, the health department said.
A test done by the China Disease Control and Prevention Center on Sunday also indicated that the man was H5N1 positive and the Chinese Ministry of Health has confirmed Lu was infected with bird flu.
The local government has adopted relative prevention and control measures. All of the 69 people who had close contact with Lu have been put under strict medical observation. So far, they have shown no signs of symptoms.
Of course, everyone of these people will be on Tamiflu, and they will all test negative.
...at least 300kg of meat, possibly infected with the virus, has made its way to retail shops but on the pretext of preventing a panic the Sanitary Inspector is refusing to disclose which ones.
Most strains of avian influenza virus are found only in the respiratory and gastrointestinal tracts of infected birds, and not in meat. However, available studies indicate that highly pathogenic viruses, such as the H5N1 strain, spread to virtually all parts of an infected bird, including meat. Avian influenza viruses survive in contaminated raw poultry meat and therefore can be spread through the marketing and distribution of contaminated food products, such as fresh or frozen meat. In general, low temperatures maintain the viability of the avian influenza virus.
Category: Bird flu * Food * Food safety * Infectious disease * Pandemic preparedness * Public health preparedness
Posted on: December 3, 2007 7:53 AM, by revere
I'm traveling so I'll let other bloggers do the heavy lifting. And I can always count on flu bloggers of note, Crof and SophiaZoe. Both discuss and link to reports of H5N1 in refrigerated turkey meat sold in stores in Poland (I particularly recommend SZ's excellent summary of the safety issues). While I don't have a lot to add to their coverage, I'd like to inject just one more issue related to finding the virus in meat
An ongoing debate is the relative contributions of migratory (wild) birds and domestic poultry to spreading H5N1 geographically. There is evidence for both mechanisms, and long distance poultry trade and smuggling is certainly one way this virus gets around. It seems to me that the virus in meat issue deserves attention as yet another way. If the virus winds up in offal and meat used as animal feed or consumer products, whether or not it infects any humans this way (which has been the focus of attention) this also becomes another means it can hitch hike around the world.
It's likely there is more of the virus "out there" in meats than we have discovered. We can be watchful but I don't think we can stop it all. Maybe this isn't a serious source of spread, which would be good news. But maybe it is, or even if it only happens occasionally, it is enough to allow the virus to gain a foothold in a new niche or location.
Just a cheerful thought for a dreary Monday.
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.
Will Bali global warming summit be upstaged by disease?
Scott Mcpherson is the CIO for the Florida House of Representatives. He writes
about a strange death of a 32 yr old police commander that occurred in Bali just prior to this global warming conference.
Bali has much to lose should tourists begin to be frightened off by news of bird flu deaths, and that may be why this story is being kept under wraps:
Currently, on FluTrackers, a thread is discussing the death last week of a Jakarta police commander on loan to the UN to help deal with security for the Bali summit. He died suddenly and, so far, inexplicably, from "difficult flu." He simply went to bed and died overnight.
this week more than 600 delegates are attending an international bird flu conference in new delhi. we can expect a steady stream of news reports, mostly rehashing things we already knew, to come from this conference.
70 million deaths isn't everyone's idea of a worst-case scenario.
many reputable scientists have spoken of numbers several times higher. if the 1918 spanish flu claimed 50 million lives, then based on population increases alone it is reasonable to assume a similar event today would claim 150 million lives.
a south korean duck farm has reported a suspected bird flu outbreak, prompting sterilization by health officials, the agriculture ministry said tuesday.
the above comments support an h5n1 outbreak in south korea. ducks rarely show symptoms of avian influenza unless infected with h5n1. an h5n1 outbreak is expected in south korea at this time of the year because of wild bird migration routes.
h5n1 was just confirmed in jiangsu province in a fatal infection, providing additional support for migrating h5n1 in the area.
Europe could join Asia and Africa as a continent where highly pathogenic H5N1 avian influenza is endemic, warns the United Nations Food and Agriculture Organization. The recent FAO warning followed Germany's detection of H5N1 avian influenza in young domestic ducks that did not have clinical signs of infection.
"It seems that a new chapter in the evolution of avian influenza may be unfolding silently in the heart of Europe," said Dr. Joseph Domenech, FAO chief veterinary officer. "If it turns out to be true that the H5N1 virus can persist in apparently healthy domestic duck and geese population.
The FAO expressed particular concerns about countries bordering the Black Sea. The region has a substantial population of domestic ducks and geese, as well as chickens, and serves as a wintering area for migratory birds...All countries bordering the Black Sea have experienced outbreaks of H5N1 avian influenza.
Researchers currently collect and test samples from individual birds -- an effective but costly and time-consuming approach. Lickfett believes he can greatly widen the scope of testing by instead sampling the water where the birds congregate during migratory stopovers.
"It probably is just a matter of time before we get that more virulent strain. It's still spreading," said Tom Gehring, CMU associate professor of wildlife biology and Lickfett's faculty advisor. "How it'll get here we don't know -- whether through wild birds or domestic poultry. But if Todd's approach works, it's going to give us a better, cheaper monitoring tool to tell us when it does.
Benin has filed an OIE report on two domestic poultry outbreaks. The birds have clinical signs of avian influenza and have tested positive on a rapid test. One outbreak was in Adjara, involving chicks and chickens. 33 of 37 birds died. They had been vaccinated against Newcastle disease on October 31. The second outbreak began December 3 in Cotonou...
The father of a Chinese man who died of bird flu has also been infected with the H5N1 virus that causes the disease, the World Health Organization reported Friday, saying it could not rule out the possibility of human-to-human infection.
Joanna Brent, a Beijing-based WHO spokeswoman, said the father began presenting symptoms on Monday and was confirmed as having the virus on Wednesday. She said he was being monitored in hospital.
"Because the possibility of human to human transmission cannot be ruled out, we will be monitoring this case closely," Brent told The Associated Press.
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.
the strange epidemiology of chinese bird flu cases
category: bird flu * china * epidemiology * pandemic preparedness * who
posted on: december 8, 2007 7:20 am, by revere
earlier in the week we discussed the unfortunate 24 year old man who died of bird flu in nanking in jiangsu province. he had had no known contact with sick poultry. now the father has bird flu. did the father get it from the son? did both get it from the same source? or two different sources? those are the open questions at the moment as chinese health authorities struggle to follow up the health status of the father's 69 suspected contacts:
"the patient, a 52-year-old male surnamed lu from nanjing in jiangsu, is the father of the serious case of bird flu diagnosed on december 2," said the statement posted on the health ministry website.
"on december 6, the china disease prevention and control center confirmed the presence of the h5n1 bird flu strain."
the man developed a fever and pneumonia symptoms on monday while under medical observation following his son's death, the statement said.
the ministry added that all people who had been in contact with the older man were under observation but no new cases had appeared, and that it had promptly notified the world health organisation.
who spokesman john rainford said cases of human-to-human transmission are very rare, citing only three previous cases in vietnam, cambodia and indonesia.
another who official, christiane mcnab, said 69 people had been in contact with lu, and none seemed to have bird flu.
"if this is a case of contact between humans, the virus isn't virulent, otherwise other people would have been infected," she said.
lu's son, 24, was hospitalised 10 days ago after developing pneumonia, xinhua news agency reported at the time, citing jiangsu health department. his condition deteriorated in hospital and he died on sunday, xinhua said.
the chinese health ministry gave no further details on the condition of the new patient, whether he had had contact with poultry, nor any information on possible human-to-human transmission. (agence france presse)
the several days between these cases is suggestive of person to person transmission. with no history (so far) of contact with sick poultry but a definite contact with a sick person, this would seem to be the logical explanation. except.
except this seems to happen so very rarely. fortunately.
still, everyone, including who seems to be whistling in the dark on this one. it would be nice if people identified as "who officials" could use infectious disease terminology correctly. virulence is the characteristic of producing severe disease in those already infected. transmissibility is the ease with which infection is passed from a source to a susceptible contact. at this point no one knows if others have been infected (e.g., they may be incubating an infection or have mild or inapparent infection (which would require a more complicated and time consuming set of tests; it seem the contacts are only being watched for influenza like symptoms). no one seems to have fallen gravely ill.
the strange pattern of chinese cases having no contact with sick poultry continues. the epidemiology of this disease in china seems quite different in that respect from indonesia and most other places reporting human infection, although vietnam, bordering china, has also reported a significant (but minority) proportion of cases without history of such contact.
A fourth centre of the H5N1 bird flu virus has been found in central Poland, about 50 km (30 miles) from three sites found last week, chief veterinary officer Ewa Lech said on Saturday.
The emergency services, following a standard procedure, set up a safety perimeter around the sites.
"The problem is the farm on which the virus was found is a big one, tens of thousands of birds," Lech told Reuters.
The...translation describes a fourth poultry outbreak in Poland. The first three were close together and resulted in infected meat distributed to retail meat and restaurant establishments. The new location (see satellite map) is about 50 km from the earlier outbreaks.
It is likely that this new outbreak is also linked to migratory birds.
indigo girl
5,173 Posts
China
Another human fatality, this time in China has been reported. Typically the
Chinese tell us after the fact as they have done in this case, however, it is
unusual that this case has had no contact with poultry.
http://www.recombinomics.com/News/12020705/H5N1_Jiangsu.html
Of course, everyone of these people will be on Tamiflu, and they will all test negative.