THE BIRD FLU REPORT

[dothedd]

 

[dothedd]

May 07, 2013


Flu infections rising among pigs in southern China, says study


Via South China Morning Post, another worry to deal with: Flu infections rising among pigs in southern China, says study. Excerpt:
Scientists said on Wednesday that flu infections were rising among pigs raised for slaughter on farms in south and southeastern China, also plagued by bird flu.

And the risk of spillover to humans was “constant or growing”, according to one of the authors of a study published in Proceedings of the Royal Society B.

Pigs are an important source of new human strains of influenza A, such as the 2009-10 H1N1 pandemic that emerged in Mexico and infected an estimated fifth of the world’s population.

Pigs can act as a “mixing vessel” in a process known as re-assortment, brewing new flu strains from swine, poultry and human viruses in areas where they live in close proximity.

Such new hybrids can be deadly – tens of millions of people died in flu pandemics in 1918, 1957 and 1968.

Luckily, the 2009 strain was about as lethal as the ordinary seasonal flu, though highly infectious.

China is currently in the grips of a deadly H7N9 bird flu virus that has killed 27 people since March, mainly in the country’s east – overlapping with the study area.

H7N9 has not been traced to pigs and has not been shown to jump from person to person, but is being closely watched for genetic changes that may make this possible.

An article in the science journal Nature last month highlighted that H7N9 seems to be circulating in areas of China that have large populations of pigs and humans “providing opportunities for further adaptation to mammals and for re-assortment with human- or pig-adapted viruses”.

For the new study, an international team of disease experts analysed data collected at an abattoir in Hong Kong over a 12-year period from 1998 to 2010, to learn more about the spread of flu among pigs.

Such information may be useful to prevent future pandemic jumps from animals to humans.

The team analysed the results of tests for virus infection at time of slaughter, as well as tests for antibodies which would indicate the pig had previously been infected and was now immune.

They observed a drop in positive virus tests by the time the pigs reached the abattoir but, worryingly, concluded this did not mean there was less infection.

“Instead, it reflects higher rates of influenza circulation on the farms where pigs are raised, so that they have already been infected [and so they’re immune] by the time they’re going to slaughter,” co-author James Lloyd-Smith of the University of California in Los Angeles said by e-mail.

The conclusion was derived from a corresponding rise in positive antibody tests.

“The prevalence of infection in swine has not decreased and so the risk of spillover to humans or birds is constant or growing,” added Lloyd-Smith.


I couldn't find the article in the Proceedings, but this sounds like a development worth watching.

[dothedd]

Friday, May 24, 2013 7:15 PM EST

China


Losses of $6.5bn
By Economy Watch

While the spread of H7N9 virus appears to have been brought under control in China, public healthcare experts say the bird flu outbreak has cost the country's poultry industry more than 40 billion yuan ($6.5 billion) in losses despite Beijing's swift actions to contain the outbreak. (2:34 pm)

MORE TOPICS: AVIAN INFLUENZA, BIRD FLU


H7N9 Virus: Human-to-Human Transmission Possible – Study
By IBTimes AU

The bird flu strain H7N9, which had so far infected 131 and killed 36 in China, could be passed on between humans through the air and close contact. (11:21 am)

MORE TOPICS: ALLERGY, BIRD FLU, HUMAN FLU, H5N1

[dothedd]

In the last 2 hours

Low Population Immunity Predicted If New Bird Flu Virus H7N9 Escalates... Medical News Today 04:21


In the last 6 hours

IT’S AIRBORNE: Human Transmission of Deadly H7N9 Virus Now Confirmed RINF 23:45 Thu, 23 May 2013


In the last 8 hours

No H7N9 virus found in poultry farms: MOA China.org.cn 21:38 Thu, 23 May 2013


Earlier today

Exposure to avian influenza H7N9 in farms and wet markets The Lancet 19:39 Thu, 23 May 2013

Reducing exposure to avian influenza H7N9 The Lancet 19:39 Thu, 23 May 2013


Yesterday

H7N9 bird flu can pass between mammals, researchers find LA Times 17:56 Thu, 23 May 2013

H7N9 bird flu found to spread through the air South China Morning Post 16:01 Thu, 23 May 2013

H7N9 bird flu spreads much like ordinary flu NBCNews.com 15:44 Thu, 23 May 2013

Desentrañando el H7N9 Elmundo 14:57 Thu, 23 May 2013

H7N9 bird flu virus spreads among mammals, inches closer to human-to-human transmission, experts warn National Post 14:55 Thu, 23 May 2013



H7N9 bird flu can spread in mammals: study Xtra 14:47 Thu, 23 May 2013

H7N9 virus closer to being human transmissible than other bird flu viruses Vancouver Sun 14:40 Thu, 23 May 2013

Ferrets, pigs susceptible to H7N9 avian influenza virus EurekAlert! 14:22 Thu, 23 May 2013

H7N9 animal model looks at transmission of H7N9 influenza virus EurekAlert! 14:22 Thu, 23 May 2013

Evolving H7N9 bird flu could close poultry markets New Scientist 14:09 Thu, 23 May 2013



H7 G228S Raises H7N9 Pandemic Concerns NOT Recombinomics 13:03 Thu, 23 May 2013

Le virus H7N9 toujours sous haute surveillance Le Temps 12:54 Thu, 23 May 2013

Aucun cas de H7N9 n'a été découvert dans les fermes d'élevage de... Chine Informations 10:32 Thu, 23 May 2013

No H7N9 virus found in poultry farms in China China Daily 10:06 Thu, 23 May 2013

Científicos chinos creen que la gripe aviar H7N9 surgió en el este... Yahoo! España 03:29 Thu, 23 May 2013



H7 G228S Raises H7N9 Pandemic Concerns Recombinomics 19:18 Wed, 22 May 2013


In the last 7 days

H7N9 bird flu appears contained, UN health experts say South China Morning Post 17:12 Wed, 22 May 2013

Infographic: H7N9 outbreak GlobalMeatNews.com 17:11 Wed, 22 May 2013

H7N9 Bird Flu Under Control In China, According To United Nations redOrbit 16:13 Wed, 22 May 2013

Scientists make new H7N9 claim Shanghai Daily 13:48 Wed, 22 May 2013

Estimates reveal low population immunity to new bird flu virus H7N9 in... BrightSurf.com 12:59 Wed, 22 May 2013



H7N9 epidemic costs China USD 6. 5 billion AGI.it 10:50 Wed, 22 May 2013

China okays H7N9 test reagents for market entry Kazinform 10:09 Wed, 22 May 2013

WHO: H7N9 bird flu in China appears under control CTV.ca 09:48 Wed, 22 May 2013

[dothedd]

Low Population Immunity Predicted If New Bird Flu Virus H7N9 Escalates Into A Human Pandemic
Article Date: 24 May 2013 - 0:00 PDT

The level of immunity to the recently circulating H7N9 influenza virus in an urban and rural population in Vietnam is very low, according to the first population level study to examine human immunity to the virus, which was previously only found in birds. The findings have implications for planning the public health response to this pandemic threat.

The study used a new, high throughput method that allows blood samples to be analysed for antibodies to multiple human and animal influenza viruses at the same time and is easier to standardise than previous techniques. However, the assay is yet to be validated clinically for the H7N9 virus, and the researchers caution that the results must be interpreted with care.

Since the first case of H7N9 infection in humans was reported in February 2013, there have been 131 confirmed cases and 36 deaths, all in China apart from one case in Taiwan. All of the infections seem to have come from infected poultry and there is no evidence of sustained transmission between people. One of the first key pieces of information that officials need when considering how best to respond to the threat of a pandemic is how much, if any, immunity the human population has to this virus. This helps to predict where the virus is likely to affect first and how likely it is that the virus will spread further. Having this knowledge also helps to understand the risks of severe infection, as well as helping to target protective measures such as where to direct antiviral medication.

Researchers at the Wellcome Trust Oxford University Clinical Research Unit (OUCRU) in Vietnam tested 1723 blood samples collected in southern Vietnam for the presence of antibodies to five different bird flu viruses, including one from the H7 sub type. The presence of antibodies would be an indication of past exposure to these particular strains of flu. They used a new technique that was developed by their research collaborators at the National Institute of Public Health of The Netherlands that is faster and easier to use than previous methods.

The results reveal that although the level of antibodies to the H7 sub-type of flu virus are higher than any of the H5 sub-types tested, levels of antibodies to all five bird flu viruses are much lower than to human flu viruses. This suggests that people living in this particular area of Vietnam have had very little or no exposure to the H7 sub-type of virus, similar to other bird flu viruses. As this population of people would be expected to be among the first to be affected in the event of a pandemic, these findings have important implications for pandemic preparedness plans in this area.

Dr Maciej Boni, a Sir Henry Dale Fellow at the OUCRU and first author of the study, explains: "H7N9 is a virus that until now has only infected birds so it's not surprising that we don't find much evidence of humans having been exposed to it. It is reassuring that in Vietnam we don't see any evidence that the current outbreaks represent a tip-of-the iceberg observation of widespread H7N9 infection in people. On the other hand, the low antibody levels indicate that there is likely to be very little immunity to this virus."

Around half of the samples were taken from an urban environment, Ho Chi Minh City, and half from a rural area, the nearby Khanh Hoa province. The team found no difference in the level of immunity to bird flu viruses between these two populations, even though people living in rural areas are more likely to live in close proximity to poultry.

"It has been suggested that people who live in closer proximity to chickens and other birds will have higher levels of immunity to bird flu viruses simply because their exposure is likely to be greater. However we find no evidence for this. Our findings would suggest that both rural and urban populations should be treated the same when considering how best to respond to the threat of an outbreak," added Dr Boni.

Professor Jeremy Farrar, Director of the Wellcome Trust Major Overseas Programme in Vietnam and the Oxford University Clinical Research Unit Hospital for Tropical Diseases, explains: "This is the first study to give us information about the level of antibodies and potentially human immunity to this new bird flu virus, H7N9 in the region. But we need to interpret the findings cautiously, these assays are relatively new and we need to understand how they correspond to existing assays and how they reflect past infection and true human immunity.

"We know that antibodies are very important for immunity to other flu viruses but at this stage, we still don't know what level of antibody measured using this assay would provide protection against this novel strain. Further studies will be needed to understand the clinical relevance of these new assays, how they compare with classic techniques and what the apparent absence of antibodies to these viruses in the human population means. However these new techniques do allow for much higher throughput of samples, ease of use and once validated may allow much more rapid assessment of the spread of infection and levels of population immunity than do traditional assays."

The study, which was carried out in collaboration with scientists at the National Institute for Public Health and the Environment (RIVM) in the Netherlands, is published online this week in the Journal of Infectious Diseases.

Professor Marion Koopmans, who is Head of Virology at the RIVM and senior author of the study, said: "We developed this technique exactly to be used in the current situation: we wanted a standardised test that allowed us to rapidly compare antibodies to the new virus with those to influenza viruses that we already know are common in people. The level of immunity to a new virus is one of the important questions during any emerging disease outbreak. We need only one drop of blood, so that tests can also be run when only small sample volumes are available, for instance when testing children. For outbreak investigations, testing of animals may be needed, and we are currently working on that. To do the clinical validation studies, we need blood samples from patients (and animals) with confirmed H7N9, and we hope to be able to do that soon through collaborations with other groups working on H7N9."

[dothedd]

Threat Of Flu Pandemic Is Real, Say MIT Researchers

Article Date: 10 May 2013 - 5:00 PDT


Many H3N2 virus strains which are circulating in pigs and birds are genetically very similar to the 1968 "Hong Kong" flu, also an H3N2 strain that spread around the world and eventually killed approximately one million people, a new study carried out at MIT (Massachusetts Institute of Technology) has found.

The researchers added that current flu vaccines may not be effective against these H3N2 strains that currently circulate only in animals. Their study has been published in the journal Scientific Reports (May 10th, 2013 issue).

Study leader, Ram Sasisekharan, said:


"There are indeed examples of H3N2 that we need to be concerned about," says Sasisekharan, who is also a member of MIT's Koch Institute for Integrative Cancer Research. "From a pandemic-preparedness point of view, we should potentially start including some of these H3 strains as part of influenza vaccines."

The evolution of flu (influenza)
Over the last century, notable flu pandemics have often emerged from birds and pigs. When a swine or avian flu virus acquires the ability to infect human beings, it often invades by bypassing the immune system, which is only able to detect strains that commonly infect humans.

The good news is that since the 1968 Hong Kong flu pandemic, many H3N2 strains have been circulating in humans. They have become less deadly, and are today even less harmful that human seasonal flu viruses.

However, several H3N2 strains that are circulating just in pigs and birds could become a much more serious threat if any of them mutated and infected humans.

Sasisekharan and team wanted to find out whether there might be a risk of these purely animal H3N2 strains from re-emerging in humans. If they did, our immune systems would not recognize them as dangerous forms of H3N2.

Four years ago an H1N1 influenza virus strain emerged; it was strikingly similar to the one that killed between 50 and 100 million people in the 1918 pandemic.

Sasisekharan said:


"We asked if that could happen with H3. You would think it's more readily possible with H3 because we observe that there seems to be a lot more mixing of H3 between humans and swine."

Genetic similarities
The team compared the 1968 Hong Kong H3N2 influenza virus strain to about 1,100 H3 strains that are currently circulating in birds and pigs. They concentrated on the gene that codes for the viral hemagglutinin (HA) protein.

The scientists sequenced the genes of HA in five locations that control how viruses interact with infected hosts, and calculated an "antigenic index" for each strain. By doing this they could determine the percentage of these genetic regions that are identical to those of the pandemic strain of 1968, giving them some idea of how easily a flu virus can bypass its host's immune system.

They also took into account the patterns of the HA protein to glycans (sugar molecules). In order to infect humans, the virus must be able to attach to glycan receptors in human respiratory tract cells.

The team sought an antigenic index of 49% or more and glycan-attachment patterns matching those of the 1968 Hong Kong flu virus. They identified 581 H3 viruses that have the potential to cause a pandemic - and these were just strains that have emerged since 2000. Thirty-two of them came from pigs and 549 from birds.

They then exposed some of the strains they identified to antibodies that were provoked by the current H3 seasonal-flu vaccines. As they had expected, the antibodies did not recognize these H3 strains, so they did not attack them. Sasisekharan said:


"Of the 581 HA sequences, six swine strains already contain the standard HA mutations necessary for human adaptation, and are thus capable of entering the human population either directly or via genetic reassortment.

"One of the amazing things about the influenza virus is its ability to grab genes from different pools. There could be viral genes that mix among pigs, or between birds and pigs."


The team are now conducting a similar study of H5 influenza virus strains.

www.medicalnewstoday.com/articles/260403.php

[dothedd]

IT’S AIRBORNE: Human Transmission of Deadly H7N9 Virus Now Confirmed

in Breaking News 5 hours ago


In April of this year researches studying the H7N9 bird flu virus in China advised global governments to get prepared for the worst case scenario. According to the World Health Organization, H7N9 is one the most lethal influenza strains ever identified because it mutates eight times faster than a normal flu virus, and according to official records, has a death-to-infection ratio of about 25%.

It was initially believed that the virus could only be transmitted to humans who have had direct contact with poultry. After 36 H7N9 deaths and 131 of infections officially reported since the virus was first identified, the worst case scenario that many feared may now be on the horizon.

The Sun China Morning Post is reporting that researches have confirmed that, not only can the virus be transmitted from one human to another, but it has gone airborne.


The H7N9 bird flu virus can be transmitted not only through close contact but by airborne exposure, a team at the University of Hong Kong found after extensive laboratory experiments.


Though the virus appears to have been brought under control recently, the researchers urged the Hong Kong authorities to maintain strict surveillance, which should include not only poultry but humans and pigs.

…

In the study, to be published today in the journal Science, ferrets were used to evaluate the infectivity of H7N9. It was found the virus could spread through the air, from one cage to another, albeit less efficiently.

Inoculated ferrets were infected before the appearance of most clinical symptoms. This means there may be more cases than have been detected or reported.

“People may be transmitting the virus before they even know that they’ve got it,” Zhu said.

SCMP via Zero Hedge

It’s important to note that the Chinese government has never been very straight forward about statistics, especially if they involve negative perceptions of their country, so in all likelihood the H7N9 virus has infected countless others.

Though it’s been called one of the most lethal flu viruses in history by WHO, Chinese scientists have downplayed the threat by claiming the effects are “mild,” and the U.S. government has up until now made no decision on whether to move forward with a vaccine for this particular strain. Earlier reports indicate that the virus is resistant to Tamiflu, a drug commonly used to treat most flu symptoms.

H7N9 is reportedly now under control in China, but we know for a fact that the virus jumped to Taiwan in April, and it may have spread elsewhere. Given that research shows the virus can spread through the air before symptoms appear, it’s certainly possibly that an outbreak is in its preliminary phase right now.

Curiously, the United Nations reports that the virus has already cost the global economy some $6.5 billion in losses. Those are massive numbers given that only 131 official cases have been reported.

We’ll know soon enough if the Chinese government has controlled the outbreak among its one billion population, and if it’s taken hold in other countries. If it’s airborne, the contagion will spread like any common cold or flu.

Pandemics have been responsible for the deaths of hundreds of millions of people throughout history, and once they start they are very hard to control. With H7N9 having a mutation rate that is eight times faster than other flu viruses, it could very well become even deadlier than it is now. Moreover, it could become even more contagious over time.

The only thing we can do at this point is to wait for news as it becomes available and take preemptive steps to prepare for the possibility of a widespread outbreak.

Hattip Satori

[dothedd]

China Society

H7N9 Bird Flu Spreads by Direct Contact in Mammals

By Cassie Ryan, Epoch Times | May 24, 2013
Last Updated: May 24, 2013 11:49 am

A health worker sprays disinfectant near the house of a 4-year-old boy infected with the H7N9 strain in Beijing on April 15, 2013. New research shows that the H7N9 bird flu virus spreads between ferrets in close contact with each other, suggesting human-to-human transmission is possible.

While the latest official news from China says that the H7N9 bird flu outbreak is now under control, a new international study urges continued caution.

According to official Chinese figures, the virus has claimed 36 lives among 131 cases, mostly in people with exposure to poultry, and there have been no further human cases since May 8. There were some instances of multiple cases in families, suggesting the possibility of transmission between humans.

Published in the journal Science on May 23, a new paper emphasizes that the virus is “infectious and transmissible in mammals,” adding that human-to-human transmission may be possible “under appropriate conditions.”

“This is a more infectious virus—it has a higher intrinsic transmissibility [among mammals]—than most of the avian viruses we’ve seen in the past,: study co-author Dr. Richard Webby at St. Jude Children’s Research Hospital in Memphis told NPR.

“On a scale from 1 to 10—from an avian virus with no potential to infect humans to a fully human-adapted strain—we don’t know exactly where this H7N9 is,” Webby added. “But I think we can safely say from these data that it might be closer to 10 than the avian viruses we’ve seen infecting humans in the last decade.”

Using ferrets and pigs as mammalian models, the research shows that the virus spreads easily when ferrets are in close contact, namely by touching, coughing, and exchange of body fluids.

“This study was designed to give us clues about the transmission of H7N9 which has affected some humans in China,” explained study co-author David Kelvin at the University of Toronto in a press release. “The animals used in the study had very mild clinical symptoms as a result of their exposure to the virus and it was clear that very close contact was required for transmission. It also appears that this virus in its present form does not transmit very well through the air.”

Kelvin added that, although the research was conducted on animals, “health care workers are at risk for transmission as they are in close contact with the individuals.”

The researchers also noted that both the ferrets and pigs were shedding the virus before they showed clinical signs of infection, showing that the disease could spread even when animals appear to be healthy.

“There’s a bit of a worry in my mind that the urgency to do something about this will drop,” Dr. Webby told NPR.

“We really need to get on top of this virus and get it out of animal populations. Otherwise it’s just not going to go away.”