PNAS: Virulence & Transmissibility Of H1N2 Influenza Virus In Ferrets

 

 

 

# 6547

 

Timing is, as they say, everything.

 

And coming on the heels the announcement 10 days ago of three human infections with a swine-origin H1N2 influenza (see Minnesota Reports Swine H1N2v Flu), a study that appears today in PNAS is certainly well timed.

 

The study, conducted at Chungbuk National University South Korea examined viruses circulating in Korean swine (H1N2 & H3N2), and found - for the most part - they were not particularly pathogenic in ferrets.

 

The exception was a triple reassortant H1N2 virus dubbed Sw/1204, that had picked up two notable mutations, and it not only transmitted efficiently, it also caused severe (even fatal) disease in the test animals.

 

The study, is called:

 

Virulence and transmissibility of H1N2 influenza virus in ferrets imply the continuing threat of triple-reassortant swine viruses

Philippe Noriel Q. Pascua, Min-Suk Song, Jun Han Lee, Yun Hee Baek, Hyeok-il Kwon, Su-Jin Park, Eun Hye Choi, Gyo-Jin Lim, Ok-Jun Lee, Si-Wook Kim, Chul-Joong Kim, Moon Hee Sung, Myung Hee Kim, Sun-Woo Yoon, Elena A. Govorkova, Richard J. Webby, Robert G. Webster, and Young-Ki Choi

 

Ed Yong, writing for Nature has the details  on this paper:

 

Need for flu surveillance reiterated

Study of Korean pigs finds virus with pandemic potential.

Ed Yong 10 September 2012

 

 

One to the two mutations discussed in this paper is hemagglutinin (HA) (Asp-225-Gly) – also known as D225G – which is something we’ve looked at a number of times in the past.

 

This mutation involves a single amino acid change in the HA gene at position 225 (H3 numbering) from aspartic acid (D) or Asp to glycine (G), and was first linked to more severe pandemic flu by Norwegian Scientists in 2009.

 

The evidence for the D222G/N  amino acid substitution driving increased virulence, and deep lung infection, has been mixed, however. A few earlier blogs include:

 

Eurosurveillance: Debating The D222G/N Mutation In H1N1

Study: Receptor Binding Changes With H1N1 D222G Mutation

WER Review: D222G Mutation In H1N1

 

The second mutation, called NA-315 (serine to asparagine the in neuraminidase) isn’t as well studied, but is believed to assist the virus in breaking out of infected cells after replicating.

 

As Ed Yong mentions in his article - viruses often have multiple amino acid changes – and we are really just beginning to understand the ramifications of these different genetic combinations. 

 

Whether this particular virus ever ends up posing a public health threat is impossible to say, but it does illustrate these swine reassortant viruses aren’t always mild in mammals.

 

New strains of influenza come about from reassortment; the swapping of genetic material between two different flu strains in a common host. We tend to focus on swine, simply because they are highly susceptible to a variety of influenza viruses, and have a history of producing reassorted viruses.  

 

 

The pandemic virus that emerged in the spring of 2009 was the end product of several influenza strains that had kicked around the world’s swine population for many years, trading bits of genetic material back and forth, until they produced a version capable of jumping to humans.

 

But any host (human, swine, avian, or other mammal) could produce a reassorted virus.

 

For more on the flu risks from swine reassortments, I continue to heartily recommend Helen Branswell’s terrific piece in SciAm  from late 2010 called Flu Factories.

Flu Factories

The next pandemic virus may be circulating on U.S. pig farms, but health officials are struggling to see past the front gate

By Helen Branswell  | December 27, 2010 |

 

And for some of my earlier looks at swine influenza, you may wish to revisit:

 

H3N2v: When Pigs Flu

You Say You Want An Evolution?

The (Swine) Influenza Reassortment Puzzle

»» Read More

South Korea Confirms H9N2 Outbreak

South Chungcheong Province – Credit Wikipedia

 

# 6221

 

 

Although considered to pose a far lower risk to humans and poultry than do the H5 and H7 strains of avian flu, H9N2 has been known to infect humans - and while generally producing mild symptoms  – is considered to have at least some degree of pandemic potential.

 

Since H9N2 circulates in many regions of the world where influenza testing is rarely done, we don’t really know how often this virus infects humans.

 

Over the past dozen years a small handful of cases have been identified – mostly in Hong Kong (see CIDRAP Avian Influenza (Bird Flu): Implications for Human Disease).

 

 

Last year Bangladesh detected a human infection and sent a virus sample to the CDC for development into a `seed strain’ for possible use in a vaccine (see  CIDRAP NEWS Bangladesh shares H9N2 virus).

 

Which brings us to a report from Xinhua News this morning on an outbreak of avian flu in Korea – first feared to be H5 – but now shown to be H9N2.

 

S. Korea confirms outbreak of low pathogenic avian influenza

English.news.cn   2012-03-13 18:32:00

 

SEOUL, March 13 (Xinhua) -- South Korea on Tuesday confirmed an outbreak of a low pathogenic avian influenza virus in chickens previously tested positive for avian flu, the government said Tuesday.

 

The Ministry for Food, Agriculture, Forestry and Fisheries said the birds at a poultry farm in South Chungcheong Province were found to have been infected with the low pathogenic H9N2 strain of the avian influenza virus that is less damaging to both birds and humans.

 

Quarantine authorities conducted thorough examinations after six of 10 chickens at the farm tested positive for avian flu. Some 100 chickens at the farm had shown symptoms of avian flu.

 

The ministry ordered the affected farm to remain under watch until restrictions on travel to and from the site will be removed.

 

 

After the widespread outbreaks of H5N1 last year in South Korea that led to the culling of millions of birds, it is no doubt a relief to officials that this turned out to be an LPAI H9 virus.

 

Unlike the H7 and H5 avian flu strains, poultry (and swine) infections by the H9N2 virus are not required to be reported to the OIE.  So we have far less data on how widespread H9N2 might be.

 

Despite causing rare human infection, H9N2 would likely need to acquire a number of genetic changes before it could pose a serious public health threat.

 

Which is why we concern ourselves with influenza’s ability to reassort with other co-circulating flu strains. Reassortment happens when two different influenza viruses co-infect the same host and swap genetic material.

 

 

 

In February of 2011, in PNAS: Reassortment Of H1N1 And H9N2 Avian viruses, we saw research from Chinese scientists that created – using reverse genetics – 128 reassorted viruses from the avian H9N2 virus and the (formerly pandemic) H1N1 virus.

 

In mouse testing, they found half of the hybrid viruses were biologically `fit’ as far as replication goes, and 8 hybrids were significantly more pathogenic than either of their parental viruses.

 

Research such as this shows the potential for the H9N2 virus to move towards a more `humanized’ pathogen. And with H1N1 and H9N2 both known to be circulating in pigs in Asia, there are ample opportunities for them to co-infect the same host.

 

While admittedly not at the top of our viral hit parade, H9N2 still commands respect. A few notable H9N2 stories from the past include:

 

• In December 2008 Revisiting A Malik Peiris Interview On H9N2

• In January of 2010, in H9N2: The Other Bird Flu Threat

• And in November of 2010 Study: The Continuing Evolution Of Avian H9N2

 

 

It is worth remembering that while everyone was watching the H5N1 virus for development, the 2009 H1N1 pandemic emerged from a completely unexpected region (North America), species (swine), and viral strain (H1).

 

All of which highlights the importance of establishing better global surveillance of humans, and farm animals, for the next emerging influenza virus.

 

Regardless of its strain.

»» Read More

Follow Up On Korea’s `Mystery Pneumonia’

 

 

# 5801

 

 

Nearly 4 months ago, in The Korean `Mystery’ Pneumonia, I wrote about confusing, incomplete, and sometimes contradictory reports regarding a number of pregnant women in a Seoul Hospital with a `mystery’ respiratory virus.

 

At the time, there were 8 pregnant women, and 1 man - who came from different hospitals and  clinics across Korea – suffering from an unusually aggressive (and rapidly fulminating) form of  Idiopathic pulmonary fibrosis (IPF) – a scaring and stiffening of lung tissue without a known cause that normally takes months or years to manifest.

 

For more background on this story, FluTrackers has maintained this extensive thread with more than 120 entries to date.

 

Although this disease was being referred to as a `mystery virus’ in the media, its exact etiology (viral, bacterial, fungal, or environmental) was unknown.

 

After some impressive epidemiological detective work, the KCDC (Korea Centers For Disease Control) believes they have found a link between the use of a specific type of sterilizing fluid used in home humidifiers and this illness.

 

While not yet able to establish a firm cause-and-effect relationship between exposure to fumes from this sterilizer and this respiratory disease, they have found that those who were exposed to it in their home humidifier were 47 times more likely to develop the condition than a control group.

The exact chemical used in this sterilizing solution was not specified by the KCDC. For now they are urging the public not to use chemical disinfectants in their home humidifiers, and to change the water daily and clean them with detergent instead.

 

The KCDC said that pregnant women were likely more susceptible to this lung damage because they spent more time at home resting, and because they tended to take deeper breaths.

 

A full report from the KCDC is expected in the coming months.

 

A couple of news items on this story include:

 

Mystery malady traced to fluid in humidifiers – Korea JoongAng Daily

Steriliser blamed for mysterious S. Korean deaths – AFP

»» Read More

Korea: Interspecies Transmission of Canine H3N2

 

 

 

# 5669

 

Many of the common illnesses we think of as `human’ diseases actually began in other species, and only later migrated to humans. The age of emerging infectious diseases in humans really began in earnest about 10,000 years ago when man began to domesticate – and live in close proximity to – other animals.   

 

• The scourge of Tuberculosis, which now infects 1/3rd of humanity, probably jumped to humans when man began to coral and raise its traditional hosts; goats and cattle.
• Measles appears to have evolved from canine distemper and/or the Rinderpest virus of cattle.  
• Influenza, as most of you know, is native to aquatic birds – but jumped species thousands of years ago and many strains have adapted to humans, pigs, and other species.

 

The list of zoonotic diseases (those shared between humans and animals) is long and continually expanding, and includes: SARS, Babesiosis, Borrelia (Lyme), Nipah, Hendra, Malaria, Hantavirus, Ebola, Bartonella, Leptospirosis, Q-Fever, bird flu and many, many others.

 

Yet despite these disease overlaps, viruses generally adapt to a fairly narrow range of species. 

 

Horse viruses generally attack equines, and not say, cats and dogs.   Cat viruses tend to attack felines, and not birds.  Bird viruses usually only infect avian species.

 

The species that a virus will infect is known as its host range.  And while usually limited, it isn't always the case.

 

Rabies is a good example of a virus that can infect an extraordinarily wide range of species.

 

 

 

We know that every once in awhile, viruses will suddenly jump to a new species. A couple of recent examples include:

 

The H5N1 bird flu virus, which has been unusually promiscuous: showing up in cats (including tigers), dogs, martens, civets, and of course humans. Researchers have successfully infected cattle with the H5N1 virus, along with ferrets and mice for testing.

 

H3N8 Canine influenza, which only showed up in dogs in 2004, had been known to infect horses for the past 40 years.

 

 

All of which serves as prelude to a report that appears in the latest edition of the Journal of General Virology, that finds a recently emerged canine H3N2 influenza virus common in Korea has now adapted to infect domestic cats.

 

 

Interspecies transmission of the canine influenza H3N2 virus to domestic cats in South Korea, 2010

D.S. Song, D.J. An, H.J. Moon, M.J. Yeom, H.Y. Jung, W.S. Jung, S.J. Park, H.K. Kim, S.Y. Han, J.S. Oh, B.K. Park, J.K. Kim, H. Poo, R.G. Webster, K. Jung and B.K. Kang

Abstract

In the last 4 years, incidences of endemic or epidemic respiratory diseases associated with canine influenza H3N2 virus in Asian dogs have been reported in countries such as South Korea and China. Canine species were considered to be the new natural hosts for this virus.

However, at the beginning of 2010, influenza-like respiratory signs, such as dyspnea, were also observed among cats as well as in dogs in an animal shelter located at Seoul, South Korea. The affected cats showed 100% morbidity and 40% mortality.

We were able to isolate a virus from the lung specimen of a dead cat that had suffered from the respiratory disease, in embryonated chicken eggs. The 8 viral genes isolated were almost identical to those of the canine influenza H3N2 virus suggesting interspecies transmission of canine influenza H3N2 virus to the cat.

Moreover, 3 domestic cats infected with intranasal canine/Korea/GCVP01/07 (H3N2) all showed elevated rectal temperatures, nasal virus shedding, and severe pulmonary lesions, such as suppurative bronchopneumonia.

Our study for the first time shows that cats are susceptible to canine influenza H3N2 infection, suggesting that cats may play an intermediate host role in transmitting the H3N2 virus among feline and canine species, which could lead to the endemic establishment of the virus in companion animals.

Such a scenario raises a public health concern, as the possibility of the emergence of new recombinant feline or canine influenza viruses in companion animals with the potential to act as zoonotic infection cannot be excluded.

 

 

The canine H3N2 virus only just appeared in Korea in 2007, and unlike the canine H3N8 virus seen in the United States, appears to have jumped directly from an avian source.

 

In 2008 the CDC’s EID Journal carried the following report on this newly emerging canine flu.

 

Transmission of Avian Influenza Virus (H3N2) to Dogs

Daesub Song, Bokyu Kang, Chulseung Lee, Kwonil Jung, Gunwoo Ha, Dongseok Kang, Seongjun Park, Bongkyun Park, and Jinsik Oh

Abstract

In South Korea, where avian influenza virus subtypes H3N2, H5N1, H6N1, and H9N2 circulate or have been detected, 3 genetically similar canine influenza virus (H3N2) strains of avian origin (A/canine/Korea/01/2007, A/canine/Korea/02/2007, and A/canine/Korea/03/2007) were isolated from dogs exhibiting severe respiratory disease.

 

To determine whether the novel canine influenza virus of avian origin was transmitted among dogs, we experimentally infected beagles with this influenza virus (H3N2) isolate. The beagles shed virus through nasal excretion, seroconverted, and became ill with severe necrotizing tracheobronchitis and bronchioalveolitis with accompanying clinical signs (e.g., high fever).

Consistent with histologic observation of lung lesions, large amounts of avian influenza virus binding receptor (SAα 2,3-gal) were identified in canine tracheal, bronchial, and bronchiolar epithelial cells, which suggests potential for direct transmission of avian influenza virus (H3N2) from poultry to dogs.

Our data provide evidence that dogs may play a role in interspecies transmission and spread of influenza virus.

 

 

The good news is that so far, these new canine viruses haven’t shown the ability to infect humans. 

 

But as the author’s of the EID study above point out:

 

Transmission of avian influenza A virus to a new mammalian species is of great concern, because it potentially allows the virus to adapt to a new mammalian host, cross new species barriers, and acquire pandemic potential.

 

Companion animals, such as dogs and cats, are of particular concern because of how closely humans interact with them.

 

While pigs might be biologically better suited as a `mixing vessel’ for influenza (see The (Swine) Influenza Reassortment Puzzle), there are far more opportunities for transmission between humans and their pets.

 

In terms of their potential to spread rapidly among humans, and cause significant morbidity and mortality, few viruses can compete with influenza. As we saw in 2009, a new influenza virus can jump species and spread around the globe in a matter of months.

 

A recurring theme in this blog is that nature’s bio lab is open 24/7, and that it is constantly trying out new genetic combinations looking for an evolutionary advantage. 

 

And for a virus, jumping to a new, immunologically naive species is like hitting the jackpot; a fresh supply of hosts and an opportunity to adapt further.

 

Which is why we watch these species jumps with more than a passing interest.

»» Read More

South Korea: Ministry Probes `Mystery’ Disease

 

 

# 5624

 

 

A brief update to yesterday’s blog Catching Up With The Korean `Mystery’ Pneumonia which mentioned the first suspected family cluster  (mother/daughter) in the recent spate of Idiopathic pulmonary fibrosis (IPF) cases being treated at a Seoul Hospital.

 

The Korean Herald (h/t Alert on FluTrackers) is reporting today that a second child in the above mentioned family – a 1 year old – is also suspected of suffering from IPF, although the child is too young for  lung biopsy and so the diagnosis is not certain.

 

 

Ministry probes mystery disease

2011-06-13 18:25

The government is keeping a close watch on three members of a family reportedly suffering from idiopathic pulmonary fibrosis.

The disease is thought to be similar to the mysterious virus which recently killed three pregnant women.

(Continue . . . )

 

 

As the story tells us, although there are many unanswered questions surrounding these cases, the Korean government continues to offer assurances that whatever the cause – they do not believe it to be an infectious disease.

 

The story also points out that while these cases are similar, they may not be related to the earlier cases (see The Korean `Mystery’ Pneumonia) reported in April and May.

 

The Korean language press has been covering this story fairly extensively, and you’ll find an ongoing thread at FluTrackers with many machine translations.

 

While sometimes useful, these automated translations tend to be difficult to interpret, and so I use them sparingly.

 

For now, the good news is that whatever the cause (viral, bacterial, fungal, environmental) of these illnesses - the number of cases remains small - and there are no obvious signs of human transmission.

 

Of course, this story continues to evolve and we’ll keep an eye on it.

»» Read More

Catching Up With The Korean `Mystery’ Pneumonia

 

 

# 5621

 

 

A month ago, in The Korean `Mystery’ Pneumonia, I wrote about confusing, incomplete, and sometimes contradictory reports regarding a number of pregnant women in a Seoul Hospital with a `mystery’ respiratory virus.

 

At the time, there were 8 pregnant women, and 1 man - who came from different hospitals and  clinics across Korea – suffering from an unusually aggressive (and rapidly fulminating) form of  Idiopathic pulmonary fibrosis (IPF) – a scaring and stiffening of lung tissue without a known cause that normally takes months or years to manifest.

 

While the cause of IPF is unknown, it normally attacks people over the age of 50, and affects both genders equally. Which makes its presentation here - primarily in younger, pregnant women – more than a little unexpected.

 

From the early reports, it appeared that these 9 patients:

 

• had no previous contact with each other
• had been transferred from various clinics around the country
• had occurred over an period of a month or more
• and perhaps most importantly, victim’s families and contacts had not developed similar symptoms.

 

Which, quite frankly, only deepened the mystery.

 

Although this disease is being referred to as a `mystery virus’ in the media, its exact etiology (viral, bacterial, fungal, or environmental) remains unknown.

 

In the thirty days since those early reports, we’ve heard very little, except that a second patient died on May 26th.  This from the Korean Herald.

 

Mystery virus claims 2nd victim

 

May 27, 2011

The second victim of a mystery virus that has infected eight patients from different parts of the country died yesterday.

According to the Korea Centers for Disease Control and Prevention, the virus, dubbed “acute interstitial pneumonia” by health authorities, killed the first pregnant woman on May 10. The second pregnant woman died at 4 a.m. yesterday.

(Continue . . . )

 

 

Two days later, Korean media reported on another pregnant woman – not among the original 8 – who at the time was presumed to have died from the same lung disease (see JoonAng Daily report Third pregnant woman dies of virus).

 

Within a couple of days, however, new reports surfaced that cast doubt on this third fatality being related to the other cases. 

 

You can find a long (60+ message) thread on these media reports (many machine translated) on FluTrackers going back to May 9th.

 

On June 6th, Alert posted on FluTrackers  a Korean language article that appeared on Hankooki.com whose title – when translated – pretty much says it all.

 

Severe lung disease, epidemiologic studies do not reveal the cause

Health authorities "is not an epidemic"

 

Which is the last we’ve heard on this story until today.

 

RoRo, another of the hardworking FluTrackers newshounds,  picked up a report from Yonhap news this morning that doesn’t reveal the cause, but that does add a new wrinkle.

 

For the first time, we have two family members presenting with the same IPF symptoms. 

 

Both (a 32 year-old mother & her 6 year-old daughter) are in critical condition, on respirators, and are in need of lung transplants.

 

2011/06/12 16:39 KST

 

Unidentified lung disease found in family members

SEOUL, June 12 (Yonhap) -- South Korea has detected what could be seen as the first case of members of the same family suffering from an unidentified severe acute lung disease, the state-run disease control agency said on Sunday.

A 32-year-old woman and her 6-year-old daughter were hospitalized in Seoul after their lung tissues became hardened and they had difficulties breathing, according to the Center for Disease Control (CDC).

(Continue  . . . )

 

 

Although this report goes on to state that  `The case is raising fears over the spread of an unknown virus’, it isn’t at all clear that the cause is viral or – for that matter – even a contagious pathogen.

 

Whatever this is, it would appear to have a preference for adult females, most of whom are pregnant.

 

The good news is, the number of cases remains very small - and with the exception of these latest two cases - all appear epidemiologically unrelated.

 

And so the investigation into this mystery continues.

»» Read More

Korea: Migratory Birds Behind Spread Of H5N1

 

 

 

# 5294

 

 

While their conclusions are hardly a surprise given the number of infected migratory birds detected this year, from Yonhap News Agency this morning we get official statements on how the worst outbreak of H5N1 bird flu in Korea’s history has been spread.

 

Since November, both Korea and Japan have reported an unusually high number of H5N1 infected migratory birds, which authorities believe have reintroduced the virus into the nation’s commercial poultry.

 

The latest Korean numbers have 40+ farms with infections, and in excess of 5.4 million birds culled.   This exceeds the size and scope of their  April 2008 outbreak, with still a 2 or 3 more months of prime `bird flu season’ left to go.

 

All of this comes amid the worst outbreak of FMD (Foot and Mouth Disease) in South Korea’s history, requiring the destruction of more than 3 million pigs, cattle, sheep, and goats since November of 2010 (see South Korea Battles Bird Flu, FMD).

 

Japan and Korea are both part of the great East Asian - Australasian Flyway, and are the winter home for many species of migrating birds, many of which spend their summers in Siberia, China, and Mongolia. 

 

 

 

Today’s report quotes Joo Yi-seok, from the National Veterinary Research and Quarantine Service, as saying:

 

"Direct contact with infected wild birds and indirect contamination caused by people and vehicles stepping on bird droppings may have triggered 22 of the confirmed cases, with the rest involving the virus being spread inadvertently by contaminated bird feed and rice husks used in coops.”

 

Here’s the link to the Yonhap report.

 

2011/02/07 14:06 KST

Migratory birds trigger AI outbreak: gov't

 

 

After the initial spread of clade 2.2 of the H5N1 virus out of Qinghai Lake in 2006 to Europe and Africa and the rest of Asia, we saw a gradual reduction in the number of wild bird die offs around the world.

 

In 2007, it was even suggested by some OIE  researchers that the H5N1 virus might be on the wane in the wild (see Avian Flu Nearing End Of It's Cycle?).

 

But the H5N1 virus isn’t a single entity.  It is a collection of at least a half dozen different clades – each capable of independently mutating, changing, or adapting over time.  

 

And so - while the incidence of some clades may subside - others may rise.

 

Bird flu reports began to pick up again in 2008 and 2009, notably in Japan, Korea, Bangladesh, and India. Talk of the virus being in decline was quickly forgotten.

 

After another lull in reporting over 2009-2010, H5N1 is once again back in the news.

 

Whether the virus was really less active during that time, or our attention was simply diverted by the H1N1 pandemic, is hard to know.  

 

But what is obvious is that while there may be some cyclical pattern to outbreaks, the HPAI avian flu virus continues to be endemic in wild birds (particularly in China and Siberia), and is reasserting itself in countries that have managed to avoid it for nearly 3 years (see What Goes Around, Comes Around).

 

For now, the H5N1 virus is primarily a threat to wild birds, poultry and agricultural interests - and to a lesser extent - those who are in close contact with birds.

 

The virus remains poorly adapted to human physiology, and very difficult to catch.  Rarer still are cases where the virus spreads from one person to another.

 

But of course, the concern is that could change over time.

 

And so the world remains at Pre-pandemic Phase III on the H5N1 virus, and we continue to watch for any signs that the virus is adapting to humans.

»» Read More

South Korea Intensifies Bird Flu Response

 

# 5220

 

 

This morning reports continue to appear indicating that the spread of bird flu in poultry (and FMD in livestock) in South Korea shows no signs of abating.

 

AFP (Agence France-Presse) reports that the South Korean government raised their bird flu alert to its second highest level on Tuesday after the virus was found to have spread to 4 provinces, in 16 separate detections.

 

Under this new alert level, all birds within a 3 KM radius of an outbreak will be culled.  Previously, that `culling zone’ was 500 meters.

 

A sampling of earlier blogs on this escalating outbreak include:

 

S. Korea: Bird Flu Moves North

South Korea Battles Bird Flu, FMD

S. Korea: 3rd Poultry Farm Positive For Bird Flu

 

Two news stories this morning. From the Straits Times:

 

Jan 11, 2011

S. Korea raises alert against bird flu - AFP

 

And from the Korea Times:

 

01-11-2011 20:55
Bird flu, FMD spreading faster, farther

By Kim Rahn

Bird flu is spreading northward to Seoul and metropolitan areas from central parts of the country.

Foot-and-mouth disease (FMD), in the meantime, has affected nearly all parts of the country, threatening the southernmost regions the most.

(Continue . . . )

»» Read More

S. Korea: Bird Flu Moves North

 

 

# 5215

 

 

Over the past two weeks we’ve seen reports of more than a half dozen H5N1 outbreaks at poultry farms located in the southern and west-central regions of South Korea. 

 

Today we learn that the bird flu virus has jumped to Anseong, about 50 miles south of Seoul. This marks the 9th farm outbreak since the end of December.

 

 

 

 

2011/01/10 15:48 KST

Bird flu spreads to northern S. Korea

SEOUL, Jan. 10 (Yonhap) -- South Korea confirmed its first bird flu outbreak in the Gyeonggi region near Seoul on Monday, raising concerns that the highly contagious disease is spreading across the country despite quarantine efforts.

 

The farm ministry said a duck farm in Anseong, 77 kilometers south of Seoul, tested positive for the virulent strain of the H5N1 avian influenza after birds started dying off over the weekend.

 

The case is the first to be reported in the province surrounding the capital city in nearly three years. Avian influenza is an airborne disease that can be transmitted to humans, although there has never been a case of a South Korean getting sick.

 

Authorities said the Anseong outbreak is the ninth confirmed in the country this winter after the first bird flu cases were confirmed by quarantine authorities on Dec. 31.

 

(Continue . . . )

 

Reportedly, over the past two weeks nearly 200,000 birds from infected farms have been culled, with many more birds destroyed at neighboring farms in an attempt to block the further spread of the virus.

 

At the same time, Korea’s agricultural industry is dealing with the worst FMD outbreak in their history (see South Korea Battles Bird Flu, FMD).

 

The last outbreak of bird flu in Korea occurred in April-May of 2008, during which time more than 8 million birds were culled. 

 

For now, bird flu remains primarily a threat to birds, and the world’s poultry industry, as the virus remains poorly adapted to human physiology. 

 

The concern, of course, is that over time that may change.  And so the world remains at Pre-pandemic Phase III on the H5N1 virus, and we continue to watch for any signs that the virus is adapting to humans.

 

»» Read More

South Korea Battles Bird Flu, FMD

 

Correction: This afternoon I received an email from a reader who kindly informed me of a relatively new FMD testing technology called DIVA (Differentiating Infected from Vaccinated Animals) that could be used to determine whether an animal tested positive due to the disease or the vaccine.

 

New tools like DIVA will hopefully enable farmers to rescue their herds by `vaccinating to live’, although so far many countries and agencies appear slow to embrace this technology.

 

DIVA testing is discussed in Animal Health Australia’s  FMD Vaccination FAQ page, and is featured prominently in the recent EXPERT OPINION ON VACCINE AND/OR DIAGNOSTIC BANKS FOR MAJOR ANIMAL DISEASES - SANCO/7070/2010  report.

 

Since I am hardly expert on FMD or DIVA testing, I would invited interested readers to check out the documents mentioned above - along with the UK site www.warmwell.com - which I’ve only begun to explore, but which seems to provide a wealth of FMD information (along with food security, animal health, rural matters and energy).

 

My great thanks to the reader who took the time to email me. I’m very happy to correct the record, and along the way, I’ve learned something new. 

 

# 5213

 

 

As feared, more farms in South Korea are detecting the highly pathogenic H5N1 virus, with three new locations reportedly identified on Sunday. 

 

In addition to several discoveries of wild birds with the virus in the southern half of the country, seven farms have now been found to be infected.

 

 

 

 

 

All of this comes amid the worst outbreak of FMD (Foot and Mouth Disease) in South Korea’s history, requiring the destruction of nearly one million animals to date.

 

First this report from Asia Pacific News, then a little more on my part.

 

S.Korea confirms more bird flu cases

Posted: 09 January 2011 1521 hrs

SEOUL: South Korea confirmed three new cases of bird flu on Sunday as the outbreak that began last month further hit farmers who were also battling the nation's worst-ever outbreak of foot-and-mouth disease.

 

The agriculture ministry confirmed three new cases of the highly contagious virus at duck farms in the southwestern county of Yeongam, bringing the total number of cases to seven since December 31.

(continue . . . )

 

 

The Double Whammy of having both bird flu and FMD striking Korean farms not only increases the economic impact of these animal diseases, it places severe strain on those agencies charged with food safety and disease control.

 

FMD (not to be confused with HFMD – a usually mild viral illness common to children) is a highly contagious viral disease that affects cloven hoof animals, but almost never infects humans.

 

It is endemic in many parts of the world (Africa, Asia, South America, some parts of Europe), but has been eradicated in many others.  The last outbreak of FMD in the United States was in 1929 – but vigilance is maintained to prevent its return.

 

There are 7 known types of FMD, along with numerous sub-types. Immunity to one type does not provide immunity to the others, and the virus continues to mutate, making it even harder to create and maintain vaccine stocks.

 

As standard antibody <edited> blood tests cannot differentiate between a diseased animal and a vaccinated animal (both carry antibodies), vaccination of herds – while sometimes necessary – can greatly delay a countries return to an FMD Free status (see correction above).

 

Both Japan and Korea detected FMD in the spring of 2010, and after the destruction of 290,000 head of livestock, Japan declared their FMD crisis over in August.

 

Korea, however, continues to find diseased animals, and has now destroyed 948,000 pigs and cattle, vaccinated another 1.5 million head, and is looking to secure enough vaccine to inoculate another 6 million farm animals.

 

Officials at the same time are now forced to deal with an expanding outbreak of H5N1 in poultry, further stressing the system, and increasing the agricultural economic impact.

 

While the current outbreak of H5N1 has not yet approached the scale of the 2008 outbreak – when 8 million birds were destroyed -  the winter `bird flu season’ still has several more months to run. 

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S. Korea: 3rd Poultry Farm Positive For Bird Flu

 

 

# 5210

 

 

A third Korean poultry operation – this time a duck farm in Jeolla Province – has been struck by the highly pathogenic H5N1 bird flu virus, raising concerns that the virus may be spreading across the country.

 

After an absence of just over 18 months, during which time Korea enjoyed a bird flu free status - wild and migratory birds have recently been discovered with the H5N1 virus in :

• Iksan, North Jeolla Province (Dec. 7) in a duck
• Seosan, South Chungcheong Province (Dec. 10) in 2 eagle owls
• Haenam (Dec. 28) in 20 Teal Ducks

 

Additionally, over the past week we’ve learned of three outbreaks in poultry operations, as indicated in the map below.

 

 

During their last H5N1 outbreak in April-May 2008, South Korea waged a month-long, very expensive battle to contain the virus that resulted in the culling of more than 8 million birds.  

 

Since then, South Korea has conducted year-round monitoring for the bird flu virus (see South Korea To Begin Year-Round Bird Flu Monitoring) in hopes of preventing future outbreaks.

 

This report from Xinhua News (h/t Dutchy on FluTrackers)

 

S Korea confirms additional bird flu outbreak

SEOUL, Jan. 7 (Xinhua) -- South Korea on Friday confirmed an additional bird flu outbreak at a duck farm in Jeolla Province, amid the country's worst outbreak of foot-and-mouth disease.

 

The Ministry for Food, Agriculture, Forestry and Fisheries said ducks at the farm in Yeongnam, South Jeolla Province, tested positive for the deadly H5N1 bird flu virus.

 

All ducks at the farm and other 70,000 birds at four farms within a 500-meter radius, totaling 84,000, have been culled as a precautionary measure.

 

The latest outbreak marks the third case of bird flu after two cases confirmed in Cheonan and Iksan on Dec. 31.

 

South Korea has been hit by avian influenza three times, with the last outbreak in April 2008. It had been a bird flu-free country since 2008, but lost this status when last month's two cases were confirmed.

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Korea: 2nd Farm Investigated For Bird Flu

 

 

# 5189

 

 

Yesterday we saw a report of suspected bird flu at a duck farm in Cheonan (see South Korea Investigating Cheonan Duck Farm).  Overnight, we’ve several media reports regarding suspected avian flu at a second farm, this time in Iksan, North Jeolla Province.

 

Test results on both of these farms are awaited.

 

Iksan is more than 100 km south of Cheonan, and is in the heart of Korea’s poultry processing region.

 

The past month has seen several H5N1 detections among wild birds and domesticated poultry in both Japan & Korea (Aprox. locations shown below).

 

 

 

This report comes from Xinhau News.

 

 

S. Korea reports suspected case of bird flu

SEOUL, Dec. 30 (Xinhua) -- A suspected case of bird flu has been reported from a chicken farm in a southeastern region of the country, raising concerns over a fresh outbreak of bird flu amid South Korea's struggle with the spread of foot-and-mouth disease, the Ministry for Food, Agriculture, Forestry and Fisheries said Thursday.

 

The ministry said a chicken farm in Iksan, North Jeolla Province, reported a suspected case of bird flu late Wednesday. Another suspected case was reported from a duck farm in Cheonan, South Chungcheong Province.

 

Health officials are testing samples from both farms, the ministry said.

(Continue . . . )

 

 

Additional media reports  (hat tips Shiloh, Arkanoid Legent, Dutchy on this FluTrackers thread) suggest that culling may have begun on at least one farm.

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South Korea Investigating Cheonan Duck Farm

 

 

# 5187

 

 

After three detections of the H5N1 bird flu virus in wild and/or migratory birds this month (see South Korea Finds 2 H5N1 Infected Owls and Korea: Bird Flu Discovered In Teal Ducks), it comes as little surprise that Korean Agriculture authorities are now investigating a duck farm where some of the birds there are showing signs suggestive of avian flu.

 

First the AFP report, appearing on Terra Daily, then some background.

 

S.Korea reports suspected bird flu case

by Staff Writers
Seoul (AFP) Dec 29, 2010

A South Korean duck farm has reported a suspected case of bird flu, the agriculture ministry said Wednesday.

 

A quarantine zone has been declared around a farm in Cheonan, about 90 kilometres (54 miles) south of Seoul, where ducks showed symptoms of avian influenza, the ministry said.

(Continue . . .)

 

Testing is underway, and we should know in a day or so if this is, indeed, H5N1.

 

South Korea has seen three previous major outbreaks of avian influenza in their poultry population.  The first in the winter of 2003-2004, and then a second time in 2006.

The largest, and most costly outbreak occurred in April of 2008, which resulted in the culling of more than 8 million birds.  You can read some of the coverage of that outbreak in these blogs:

 

Korea: Cat Death Attributed To Bird Flu

South Korea Investigating New Outbreak

S. Korea Finds 2 More Suspected Outbreaks

 

At the same time as these Korean outbreaks in 2008, Japan reported the discovery of the H5N1 virus in four swans in Akita Prefecture (see Japan Confirms Swans Infected With H5N1).

 

Similarly, this month Japan and Korea are once again both reporting multiple instances of H5N1 in wild and/or migratory birds.  I’ve plotted the general locations on the map below.

 

All of which has agricultural interests in Japan and Korea on high alert, in hopes of avoiding another widespread outbreak like was seen two years ago.

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Korea: Bird Flu Discovered In Teal Ducks

 

 

# 5183

 

 

Each winter, countless thousands of migratory birds make their way south from Mongolia, Siberia, and parts of China to over-winter on the Korean peninsula and in Japan.

 

In recent weeks we’ve been hearing of a small number of migratory birds being discovered in Japan, and to a lesser extent, in Korea (both are part of the East-Asian Flyway) with bird flu.  

 

 

 

Today, via Yonhap News, we learn of 20 teal ducks – found dead in Haenam - that have tested positive for a virulent (probably, but not stated to be H5N1 in this report) bird flu virus.  This is the third such discovery in a month, according to this report.

 

 

2010/12/28 17:04 KST

Dead teal ducks with bird flu strain found in S. Korea

 

SEOUL, Dec. 28 (Yonhap) -- South Korea's farm ministry said Tuesday that it has found 20 dead spectacled teal ducks, apparently affected by the virulent strain of bird flu, and have taken emergency decontamination measures.

The discovery of the dead birds in Haenam 430 kilometers south of Seoul is the third such finding this month and is raising concerns among local poultry farmers.

 

I’ve mapped the three main locations below, which are clustered near the end of the migration path for many of these birds.

 

 

Dutchy on FluTrackers has a thread with a couple of more translated news accounts, that identifies the strain as H5N1. 

 

You can follow that thread here.

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Monoclonal Antibodies Revisited

 

 

# 4415

 

 

Every few months we seem to see a new press release or news story about some whiz-bang invention, discovery, or experimental drug that promises to revolutionize the way we treat or prevent influenza.   

 

Often these stories are about discoveries that hold genuine promise, but that are still some time away from practical application. 

 

This morning we’ve a press release and some news stories about a Korean company working on Human Monoclonal Antibodies (moAb) that are designed to work against a wide variety of influenza viruses. 

 

This from The Korean Times.

 

New Anti-Influenza Drug Being Developed

By Bae Ji-sook
Staff Reporter

Celltrion has developed a drug based on "human monoclonal antibodies" that can be effective against multiple influenza viruses, the biopharmaceutical company said Tuesday.

 

The company tentatively called the drug a Super Flu-Antibody Therapy.

 

This is the first time a drug effective against multiple viruses has been developed in Korea. Celltrion expects to release the product next year, ahead of major rivals in the U.S. and other countries who have also been successful in developing substances that are effective against one or more viruses.

 

(Continue . . . )

 

 

If all of this sounds a tad familiar, it may be because a little over a year ago researchers at the Dana-Farber Cancer Institute (Dana-Farber), Burnham Institute for Medical Research (Burnham) and the Centers for Disease Control and Prevention (CDC) reported the identification of human monoclonal antibodies (mAb) that worked against a wide range of influenza viruses, including the H5N1 bird flu virus.

 

See Research: Monoclonal Antibodies Against Influenza

 

These antibodies targeted a highly conserved stem region of the H5 hemagglutinin (HA) which prevented the virus’s entry into a cell, and this portion of the virus is consistent across many (but not all) influenza strains.

 

Potentially a `magic bullet’ against influenza, assuming that it works as well (and as safely) in humans as it did in laboratory mice.

 

These monoclonal antibodies would not work like a vaccine, which confer relatively long-term protection.  Rather, a single injection is expected to serve as a treatment, or to work as a temporary prophylaxis.

 

Monoclonal antibodies are viewed by many researchers to hold promise for influenza treatment, but human trials have not been conducted, and substantial uncertainties exist.

 

Celltrion, Inc has released an optimistic sounding press release today on their latest monoclonal antibody research on mice, promising to move forward with clinical trials `as quickly as possible’.  

 

You can read the release at the link below.

 

Successful Development of Broad Spectrum Human Monoclonal Antibodies Against Major Influenza Viruses (H1N1 and H5N1)

 

Even if successfully brought to market in the next few years, monoclonal antibodies are not likely to become a panacea against a pandemic.  These are injectable, short-lived medications that are likely to remain expensive and limited in availability for the foreseeable future.  

 

Regardless of how these clinical trials turn out, or whether monoclonal antibodies prove to be a practical treatment for influenza down the road, this is another important step forward in our understanding of how influenza viruses work.

 

And that, over time, will no doubt pay big dividends.

»» Read More

Report: North Korea Struggling With Pandemic Virus

 

# 4201

 

 

Although the North Korean government has had very little to say about it, reports continue to filter out of that closed, impoverished country that suggest the pandemic virus is having a serious impact.

 

Earlier this month, in a humanitarian gesture, South Korea offered emergency supplies (including Tamiflu) to the north, to help them fight the pandemic (South Korea Offers Pandemic Humanitarian Aid To The North).

 

Today, the Wall Street Journal has a report – gleaned from information provided by the Good Friends aid group working in North Korea – that suggests the situation in that country may be more serious than previously thought.

 

 

 

     DECEMBER 30, 2009, 6:50 A.M. ET

North Korea Fights H1N1

By JAEYEON WOO

North Korea sent out a nationwide alert in recent days about the apparent worsening spread of H1N1 flu there, according to an aid group with contacts in the country.

 

The notice by the Seoul-based Buddhist aid group Good Friends follows the South Korean government's shipment of 400,000 doses of the flu treatment Tamiflu and 100,000 doses of the treatment Relenza to its impoverished neighbor earlier this month amid fears that a delayed response to the disease in the North could lead to serious consequences for the South.

 

Good Friends said this week that North Korean officials had issued a statement that said patients suffering from the disease should be given priority. The group said the statement was of a type issued only twice before, for seriously wounded soldiers during the 1950-1953 Korean War and for a deadly skirmish with South Korea in 2002.

 

The true picture within highly restrictive North Korea is difficult to determine. Officials there couldn't be reached.

(Continue . . . )

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Farm Flu In Korea

 

 

# 4198

 

Two unrelated stories, except that they involve farm animals in South Korea infected with two very different influenza viruses; one human adapted, and one low-path avian.

 

While neither story is particularly alarming, they do illustrate how difficult it is to keep human and avian flu strains out of domesticated livestock.   

 

South Korea tests livestock more rigorously than many other nations, and understandably reports these sorts of infections more often than many other countries.   It is pretty safe to assume that similar infections are going unreported in many places around the world.

 

 

Number of H1N1 Infections Growing on Pig Farms

SEOUL, SOUTH KOREA - South Korea reported today another case of H1N1 infection at a local swine farm, adding to a growing list of pigs infected with the flu, local media reported.

 

The latest outbreak occurred in a pig farm in Jeungup, Jeolla Province, marking the sixteenth confirmed case of H1N1 infection since mid-December when five farms reported infection for the first time in the country, according to local media.

 

Authorities are suspecting pigs in the latest case might have contracted the virus through human contacts and expecting them to be naturally cured, according to media reports.

 

The country's farm ministry plans to take quarantine measures and vaccinate hog industry and health workers in an effort to stem further spread, local media said.

 

 

Low path H5 and H7 viruses are reportable animal diseases, even though they pose little health hazards to humans.   Low pathogenic viruses have the potential to mutate into highly pathogenic viruses, therefore their appearance is taken seriously.

 

 

S. Korea: Low pathogenic H5N2 in ducks

29 Dec 2009

On a duck farm in South Korea low pathogenic bird flu type H5N2 has been diagnosed.

 

The duck farm in Chung Chong-Namdo (Gobuk-myeon, Seo-san city) holds 26,800 duck of which 40 birds were found to be positive for H5N2. The source of the infection could not be established.

 

As part of the yearly surveillance programme, a member of the Livestock Health Control Association collected samples from a duck raising farm in Seo-san city and requested the test for avian influenza to the Chungchong-namdo Veterinary Research Institute (VRI) on 7 December 2009.

 

<SNIP>

26,800 ducks raised in the affected farm were culled and 176,000 eggs kept in the farm were destroyed.

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South Korea Reports A Tamiflu-Resistant H1N1 Fatality

 

 

 

# 4163

 

 

Even though the vast majority of novel H1N1 strains tested to date remain sensitive to Tamiflu, we’ve seen reports of more than 100 resistant samples from around the world.

 

An indication that – while still rare – growing Tamiflu resistance is a concern.

 

Undoubtedly there are far more resistant cases out there than we are aware of, given the very limited testing that is conducted.   But random sampling indicates that as a percentage of total cases, that number remains very low.   At least for now.

 

Oseltamivir (Tamiflu) Resistance is associated with the swapping of the amino acid histidine for tyrosine  at position 275 (N1 numbering) in the neuraminidase glycoprotein (H275Y).

 

 

The concern is that novel H1N1 could eventually become widely resistant to oseltamivir (Tamiflu), just as its seasonal H1N1 cousin did a couple of years ago.   The resistant viruses tested so far still remain sensitive to Zanamivir (Relenza), GSK’s alternative antiviral.

 

Today, a sad but inevitable story of a 1 year-old who succumbed to a Tamiflu-resistant strain of the H1N1 virus.   Despite the headline, this is not the first recorded Tamiflu-resistant flu fatality.  

 

The Cluster at Duke University Hospital in North Carolina involved 3 deaths. (see Duke Hospital Reports No Further Spread Of Resistant Strain).   These were among severely immunocompromised cancer patients, however.

 

This report from Xinhua News.

 

S Korea reports world's 1st Tamiflu-resistant death case

17:21, December 17, 2009

A South Korean infant, whose body showed no response to anti-viral drug Tamiflu, died of pneumonia and respiratory failure on Thursday, the country's health authorities said, which local media say is the first such case in the world.

 

The one-year-old girl, who was suffering nervous-system disorders, was hospitalized for high fever and coughs last month, but her conditions continued to deteriorate despite taking Tamiflu, or double doses of it in her final days, according to Ministry of Health, Welfare and Family Affairs.

 

Health authorities last week confirmed the virus resistant to Tamiflu was found in the infant's body.

 

This is the first such fatality reported at home and abroad, with South Korea having reported two other similar cases of Tamiflu-resistant patients and the World Health Organization 102 cases worldwide, Seoul's media reports said.

 

The girl was too young to be given relenza, which is approved for treatment in children who are seven years and older, according to local media.

 

South Korea has posted 117 A/H1N1 flu fatalities as of Dec. 4, according to data collected by the health ministry.
Source: Xinhua

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South Korea Offers Pandemic Humanitarian Aid To The North

 

 

# 4134

 

 

Although `officially’ the North Korean government has yet to report any cases of the novel H1N1 virus, reports continue to filter out of that closed nation that the virus is spreading.

South Korea today, based on these reports, has offered humanitarian aid to the North, although it isn’t clear whether it will be accepted.

This from Yonhap News.

 

 

Lee orders measures to help N. Korea deal with H1N1

SEOUL, Dec. 8 (Yonhap) -- South Korean President Lee Myung-bak ordered his government Tuesday to help North Korea deal with a possible outbreak of Influenza A, saying the disease could do serious damage throughout the impoverished state.

"There are reports of an outbreak of the new flu in North Korea, so find ways to help North Korea after confirming the reports," the president was quoted as saying in a Cabinet meeting by his office Cheong Wa Dae.

North Korea has not yet announced any local case of the H1N1 virus, but Good Friends, a Seoul-based aid group, said in its Monday bulletin that about a dozen people have died from the disease there. Schools started winter vacation a month early on Dec. 4 due to the rapid spread of disease, the aid group said, citing sources inside North Korea.

Relations between the two Koreas quickly deteriorated after Lee, a conservative, was inaugurated early last year with a pledge to condition inter-Korean exchanges on progress in Pyongyang's denuclearization.

Lee, however, said any assistance to the North in dealing with the H1N1 virus must be strictly humanitarian and unconditional, his spokesman Park Sun-kyoo said.

"Such assistance must be provided swiftly as the disease could quickly spread in North Korea where conditions are not so good," Lee was quoted as saying.

(Continue . . . )

 

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South Korea: LPAI Detected

 

 

# 3989

 

Chuncheon, Gangwon Province

 

We’ve very little information right now, other than this report from the Chosun Ilbo.    It doesn’t even tell us what strain of avian influenza virus was detected, only that it was low path.

Assuming that it is an H5 or an H7 virus, the OIE should receive notification in the next couple of days.

 

 

Fresh Bird Flu Outbreak Worries Health Officials

The resurgence of bird flu in Chuncheon, Gangwon Province is causing concerns to health authorities as the H1N1 flu scare continues. A low pathogenic bird-flu virus was found in excrement of migratory birds in a reservoir in Chuncheon.

 

Despite the low infectiousness, health authorities claim they cannot rule out danger to humans or mutation and pledged to stay alert.

 

The worst-case scenario is that patients infected with the H1N1 virus could additionally contract bird flu, leading to a mutation that gives rise to a new supervirus. "But that doesn't necessarily mean that a new form of virus will be formed when the bird flu virus appears amid the spread of H1N1 virus," a health official said. "But if that did actually happen, the situation we've seen so far would be a mere shadow of what lies ahead. That's why we have to take preventive measures."

 

Disease prevention headquarters on Tuesday said it will vaccinate some 40,000 fowl breeders from the third week of this month instead of December as originally planned.

 Nov. 11, 2009 11:43 KST

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