EID Journal: Influenza A(H5N6) Virus Reassortant, Southern China, 2014

 

# 10,020

 

Although we’ve yet to see a definitive move by any of the recently emerged novel flu viruses towards becoming a global public health threat, the rapid increase in the number of these viral contenders over the past three years has been remarkable. 

 

Not so very long ago we really only had one HPAI virus of genuine concern; H5N1.

But as both LPAI and HPAI viruses like H9N2,  H7s, H6’s, H5’s, and others have comingled in poultry operations and wild birds, and have reassorted and spread, they’ve evolved into new – sometimes highly pathogenic versions. 

 

Recently emerged viruses include  H7N9, H5N8, H5N2, H5N3, H5N5, H5N6, H6N1, H10N8 . . . .

 

Prime among these new viral upstarts has been the H5N6 virus, which first came to prominence just one year ago, after it emerged in a Sichuan China poultry flock, and infected (fatally) one man in Nanchong City.  Since then we are aware of at least 2 additional human infections (1 survived) in China, along with dozens of outbreaks in China and Vietnam.

 

Six months after it appeared, we saw an  FAO-EMPRES Report On The Emergence And Threat Of H5N6, with our first detailed look at H5N6, along with a short list of other newly emerged HPAI H5 viruses (including H5N8 & H5N3), that presciently warned

 

Today we have a letter appearing in the CDC’s EID Journal, which describes the more-or-less simultaneous appearance of novel H5N6 in both China and Laos in March of 2014, and describes its evolution as:  `reassortants of wild duck H5N1 and H6N6 viruses, both of which have pathogenic and potential pandemic capacity in southern China’.

 

I’ve snipped some of the more technical sections and have re-paragraphed some of it to improve readability, so many of you will want to follow the link below to read this letter in its entirety.

 

Volume 21, Number 7—July 2015

Letter

Influenza A(H5N6) Virus Reassortant, Southern China, 2014

Hanqin Shen¹, Boliang Wu¹, Yimin Chen, Yingzuo Bi, and Qingmei Xie

To the Editor: Avian influenza A viruses generally do not cause disease in aquatic birds, the natural reservoir of these viruses (1). Influenza A(H5N6) was first isolated from mallards by García et al. in 1975 (2). Influenza viruses continue to evolve and reassort to generate novel, highly pathogenic viruses. Novel H5 highly pathogenic avian influenza virus subtypes, such as H5N2, H5N5, and H5N8, have been reported (3,4).

Highly pathogenic influenza A viruses are endemic to many countries (http://www.oie.int/en/animal-health-in-the-world/update-on-avian-influenza/2015/), cause tremendous economic losses to the poultry industry, and represent a serious threat to public health.

In March 2014, an influenza A(H5N6) outbreak caused the death of 457 birds in Laos (http://www.oie.int/wahis_2/public%5C..%5Ctemp%5Creports/en_imm_0000015052_20140507_182757.pdf).

During the same month, a flock of ducks in Guangdong Province in southern China exhibited typical respiratory signs of influenza A virus infection. This flock also had 70% decreased egg production and a slightly increased mortality rate. Throat swab specimens were taken from the symptomatic and dead ducks, and the samples were used to inoculate chicken embryos for virus isolation.

Hemagglutination (HA) and neuraminidase (NA) inhibition assays were performed to identify the subtype of the isolated virus, which was designated A/duck/Guangdong/GD01/2014 (H5N6) (GD01/2014). The complete RNA genome was amplified by reverse transcription PCR and cloned into the pMD-19T vector for sequencing (5). The complete genome sequence of the GD01/2014 virus was submitted to GenBank (accession nos. KJ754142–KJ754149).

<SNIP>

In summary, in 2014, outbreaks of H5N6 virus occurred in China, Laos, and Vietnam and caused the deaths of infected humans in Sichuan province, China (http://www.oie.int/en/animal-health-in-the-world/update-on-avian-influenza/2014/; http://www.wpro.who.int/china/mediacentre/releases/2014/20140507/en/).

We characterized the novel reassortant H5N6 virus in China and found that it was the same genome type as and was highly homologous with the H5N6 virus in Laos. However, the adaptation, host range, and virulence of this reassortant H5N6 virus are still unclear and should be further investigated. Furthermore, the potential for infection, outbreaks, and pandemic in other poultry and mammals should be carefully monitored.

(Continue . . . )

 

 

Hong Kong: Oriental Robin Tests Positive For H5N6

Photo Credit- Wikipedia

 

# 10,010

 

Last week, in Hong Kong: Oriental Magpie Tests Positive For H5, we looked at the second detection of a wild bird in Hong Kong with HPAI H5 in a matter of three weeks. While we’ve seen birds carrying H5N1 show up in Hong Kong before, the peregrine falcon discovered on April 9th was the first imported case of HPAI H5N6 ever reported in the Territories.

.  

Today it was announced that the oriental magpie-robin discovered last week was also infected with the H5N6 virus.  This from the Hong Kong Government announcement.

 

Oriental magpie robin tests positive for H5N6 virus

The Agriculture, Fisheries and Conservation Department said today (May 5) that an oriental magpie robin found in Sai Kung was confirmed to be H5N6 positive after a series of laboratory tests.

The sick bird was found and collected near 10B Sha Kok Mei First Lane, Sai Kung, on April 29.

The AFCD will continue to conduct inspections of poultry farms to ensure that proper precautions against avian influenza have been implemented.

The spokesman reminded people to observe good personal hygiene. "They should avoid personal contact with wild birds or live poultry and clean their hands thoroughly after coming into contact with them," he said.

Ends/Tuesday, May 5, 2015
Issued at HKT 11:28

 

 

One of the recently emerged  HPAI H5 viruses, it made headlines almost exactly one year ago when it produced at least one fatal human illness in Nanchong City, China, and  was contemporaneously identified in local poultry (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu). 

 

Since then it has infected at least two more in China, and has sparked at least 3 dozen poultry outbreaks across China and Vietnam.

Credit OIE Follow up Report # 7

 

Along with H5N8, H5N2, and the venerable H5N1 virus -  this upstart addition to HPAI H5’s lineage has been making impressive gains geographically - presumably being spread by migratory birds.  Before H5N8 began its big move last fall into Europe and North America (and spawned North American HPAI H5N2), the H5N6 virus was very near the top of our `avian flu strains to watch’ list.

 

In early November 2014, in FAO-EMPRES Report On The Emergence And Threat Of H5N6, we saw our first detailed look at H5N6, along with a short list of other newly emerged HPAI H5 viruses (including H5N8 & H5N3), that presciently warned

The possibility exists that wild birds could become infected and spread these viruses to other countries or continents. Migratory birds, which have played a key role in the introduction of H5N1 to Europe and Africa [Kilpatrick et al, 2006] and of H5N8 to the Republic of Korea [Jeong et al, 2014], could spread the viruses to other countries or continents.

Three weeks later it was announced that HPAI H5 had arrived in the Pacific Northwest, and since then it has spread across two provinces in Canada and 18 U.S. states.  H5N8 also winged its way into Europe last winter, making it as far as the UK.

 

Although not spreading in anywhere near as spectacular fashion as H5N8 or H5N2, the fact that H5N6 has already demonstrated a limited ability to infect humans when its more-traveled cousins have not, provides it with a bit of extra gravitas.

Making H5N6 very much still a virus to watch.

Hong Kong: Wild Bird Found Infected With H5N6

Photo Credit- Wikipedia

 

# 9945

 

While we rarely hear of avian flu infected wild birds out of China (likely due to less than robust surveillance & reporting) – over the past decade we’ve seen numerous reports out of Hong Kong (see Egrets, They’ve Had A Few . . .  and Hong Kong: Two H5 Positive Gulls Found) of sick or dead migratory birds with the H5N1 virus.

 

In December of 2008 Hong Kong saw their first outbreak of H5N1 in domesticated poultry in nearly 6 years. In early 2009 it was announced that the H5N1 outbreak was `likely’ caused by infected migratory birds.  See Wild Birds Eyed As Likely Source Of Hong Kong Bird Flu  Outbreak.

 

Up until the past couple of years, the H5N1 virus has been the primary concern, but with the recent expansion of H5 and H7 viruses in Chinese poultry and the recent arrivals of H5N8 in Taiwan and Japan, H5N1 is now far from the only threat.

Last week is was reported that a Peregrine falcon tested positive for H5 virus in Hong Kong, and that further tests were underway to determine the subtype.  Today we learn that this bird was infected - not with H5N1 – but with the recently emerged H5N6 virus.

 

First case of H5N6 virus found in wild bird in Hong Kong

A spokesman for the Agriculture, Fisheries and Conservation Department (AFCD) said today (April 16) that the carcass of a peregrine falcon found at a construction site on Hung Yuen Road, Hung Shui Kiu, Yuen Long on April 9 was confirmed to be H5N6-positive after a series of laboratory tests.

It is the first case of H5N6 virus found in a wild bird in the territory. The AFCD will closely monitor the situation.

The AFCD will continue to conduct inspections of poultry farms to ensure that proper precautions against avian influenza have been implemented.

The spokesman reminded people to observe good personal hygiene. "They should avoid personal contact with wild birds or live poultry and clean their hands thoroughly after coming into contact with them," he said.

Ends/Thursday, April 16, 2015
Issued at HKT 18:01

 

 

H5N6 is one of several HPAI H5 reassortants that have appeared in China over the past couple of years (others include H5N8, H5N2, H5N3, H5N5), and like its more famous H5N1 cousin – H5N6 has demonstrated the ability to infect humans.

 

Although we only first heard about H5N6 a year ago (see (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu), it has since been reported across large swaths of China and as far south as central Vietnam. Last October, in China: H5 AI Rising, we looked at 24 recently reported outbreaks of H5N6 across China.

 

The following month, in FAO-EMPRES Report On The Emergence And Threat Of H5N6, we looked at an analysis of H5N6, and other recently emerged avian flu viruses in China. Since then, two more human cases have been reported see China Reports 3rd H5N6 Case (Fatal) – Yunnan Province), of which only one survived.

 

Although it has not spread as well or as far as the recently emerged H5N8 virus (and its reassortant progenies),  H5N6 is nonetheless a virus to watch.

Media Report: 2 H5N6 Cases In Nghe An Province (Updated)

 

UPDATED:  Apparently my initial concerns with this story were warranted, as media reports this morning now indicate that the 2 patients suspected of H5N6 infection have tested positive for seasonal influenza instead (see report at bottom).

 

# 9903

With the caveat that we are dealing with a media report, and I’ve yet to locate an official source, today several Vietnamese news sites are carrying a report of two people infected with the recently emerged A/H5N6 avian virus in Nghe An Province.

 

Giving at least some credence to this report is the fact that just over two weeks ago we saw the virus reported in the adjacent province to the north (see H5N6 Reported In Thanh Hóa Poultry).

First the report, then I’ll be back with a bit more.

 

Nghe An: Detecting 2 patients infected with influenza A / H5N6

TPO - An outbreak of avian influenza A / H5N6 outbreak in Quy Hop district, Nghe An infection caused two people. Local Veterinary Authority has issued 11,000 doses of vaccine prevention, control the outbreak.

The source of the Pioneer said, outbreaks of avian influenza outbreaks in the neighborhood Dinh Xuan Nghia, Quy Hop district, Nghe An, near the tip. Place of concentrated populated, located on Highway 48A. Following 2 people infected with bird flu.

Talking to reporters dimension 5/4, Director DARD Nghe An Ho Ngoc Sy confirm the source said, adding, after the outbreak, the veterinary authorities in collaboration with the district of Nghe An advanced Quy Hop emergency measures to enclosure, control and extinguish the outbreak.

"There are families raising chickens, 150 children in infected chickens. The province has mobilized 11,000 doses of vaccine against the disease and conduct quarantine, disinfection whole barn area with bird flu. Temporarily banned the sale of poultry in the affected area, "said Ho Ngoc Sy said.

Director of Health Services of Long Bui Dinh Nghe An, said two patients infected with avian influenza A / H5N6 was transferred to Hanoi treatment. The patient was his wife Tr.K.Ch, LTTh. Housing neighbor Dinh Xuan Nghia, Quy Hop district, he Ch. poultry husbandry; His wife has just joined the women in the neighborhood classifieds market has traded Palace.

 

One of the `new crop’ of HPAI H5 viruses to appear over the past 18 months – H5N6 –  unlike H5N8 and H5N2, has shown an ability to infect and seriously sicken humans.

 

We first saw it appear, infecting poultry and killing one person, last April in Nanchong City (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu). Since then, two more human cases have been reported in China, of which only one survived.

 

In early August of 2014 the virus suddenly popped up in widely separated outbreaks in central and northern Vietnam (see OIE: Two Outbreaks Of H5N6 In Vietnamese Poultry), hundreds of kilometers south of its original emergence.  Since then there have been at least a half dozen additional reports of outbreaks in Vietnamese poultry.

 

Over the past few months China has reported more than 2 dozen outbreaks around the country (see OIE Follow-up report No.7) , and two days ago FluTrackers picked up an unconfirmed report from China - Farmer suspected H5N6 bird flu case after outbreak in geese - April 3, 2015.

 

Although it has not spread as far, or as famously, as H5N8 and H5N2 – H5N6 is viewed with extra caution because it has already demonstrated the ability to infect humans (see FAO Warns on H5N6).

 

Hopefully we’ll get clarification on both of these incidents in the next couple of days.

 

UPDATE:

This morning several Vietnamese news outlets are carrying reports indicating that both cases tested positive for regular flu, not H5N6. This from Vietnamplus.

 

Nghe An confirmed no patients infected with influenza A/H5N6

Dr. Phan Van Cong, head of communicable disease control, biological vaccines, preventive health center of Nghe An province, confirmed the province doesn't have any patients infected influenza A/H5N6 as the communication media has brought.

In mid March, 2015, an outbreak of influenza A/H5N6 were erupting on chickens at communal Sense Spring (district of Nghe An, Where your knees). General Tran Kim's family and her sister Lü BU in A Phoenix neighborhood, civil Sense Spring chickens and there have been dozens of chickens infected and die.

On March 3, Mr Chan Kim Chung caught a cold, high fever. To 31/3, sister Lü BU Thuy (his wife Chung) also have a cold, high fever. Fear before public health situation with the flu have occurred on the adoptive family's chickens, relatives have taken the couple Mr. and Mrs. Chung, Cards out at the Oph parasite Virus, a tropical hospital Central.

After doing tests, the hospital reported two patients with influenza A is common sense. A central tropical hospital has been treating patients with antibiotics, the pill provides reproductive. After six days of treatment at a hospital on the Central Lowland, both Public Health and the patient has stabilized, recovered. Expected in the afternoon of 6/4, British couple, the Cards will be discharged from hospital.

Media Reports: H5N6 Reported In Thanh Hóa Poultry

Thanh Hoa Province – Credit Wikipedia

 

# 9839

 

One of the `second generation’ of HPAI H5 viruses to appear over the past 18 months – H5N6 – is one that that, unlike H5N8 and H5N2, has shown an ability to infect and seriously sicken humans. We first saw it appear, infecting poultry and killing one person, last April in Nanchong City (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu). 

 

Once the threat was identified, local poultry was culled, and we heard nothing more for several months.

 

All was quiet regarding  H5N6 until early August, when the virus suddenly popped up in widely separated outbreaks in central and northern Vietnam (see OIE: Two Outbreaks Of H5N6 In Vietnamese Poultry), hundreds of kilometers south of its original emergence.

 

Over the next few weeks we began to see additional outbreaks in Vietnam (see Vietnam Gears Up To Detect, Fight Avian H5N6) and two thousand miles away in northern China (see China: H5N6 Outbreak In Heilongjiang Poultry).  Laos has also reported outbreaks in poultry.

.

Last October, in China: H5 AI Rising, we looked at 24 recently reported outbreaks of H5N6 across China.

 

The following month, in FAO-EMPRES Report On The Emergence And Threat Of H5N6, we looked at an analysis of H5N6, and other recently emerged avian flu viruses in China. Since then, two more human cases have been reported see China Reports 3rd H5N6 Case (Fatal) – Yunnan Province), of which only one survived.

We’ve not seen an OIE report from China on H5N6 since early February (Follow-up report No. 5) and Viet Nam has been unusually quiet since the New Year as well, with just a small number of H5N1 and HPAI H5 outbreaks reported in 2015.

 

Today, however, we have multiple media account of a recent outbreak of H5N6 in Thanh Hoa. I’ve checked the Vietnam’s MARD website, but no notice has been posted at this time.  If confirmed, we should see an OIE notification in the next few days.

 

Thanh Hóa: appeared bird flu A/H5N6

AFP From mid March, 2015, at Thanh Hoa, bird flu has appeared in a household in Hai Tinh Gia district, which Fields nearly 300 children infected poultry. Sample swabs for the positive result for influenza A/H5N6.

Bird flu appear on household flocks Le post added, Hamlet 2, Hai Tinh Gia district Chiefs Township to 293 the poultry (ducks, 103 190 chicks) infected.

According to the results of tests by the veterinary agency 3, sample swabs positive for influenza A/H5N6. This is the strain of the virus causing the bird flu threat, viruses have high and can spread to people with high mortality rates.

This is a new virus strains emerge in Thanh Hoa province, poultry vaccination has not been immune to this virus type. On the other hand, prolonged overcast weather increases the risk of epidemic scale.

Before the situation on the Thanh Hoa province, has express about making urgent measures in prevention of avian influenza A/H5N6.

(Continue . . . )

 

Similar reports are available from The Voice Of Vietnam (see Thanh Hoa appear outbreak of avian influenza H5N6) and Workers (see Influenza A / H5N6 appeared in Thanh Hoa).

Although not as well known, or as well distributed as H5N8 and H5N2 – H5N6 is viewed with extra suspicion because it has already demonstrated the ability to infect humans (see FAO Warns on H5N6) 

 

But as with the H5N1 virus, we’ve not seen any evidence that it is capable of transmitting efficiently from human-to-human.

Guangdong’s H5N6 Patient Recovers

Credit Wikipedia

 

# 9648

 

Normally the recovery of a single avian flu patient wouldn’t rate a separate blog entry, but since this is only the second human H5N6 case diagnosed - and the first one was fatal (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu) - the recovery of the 58-year old man diagnosed last December from Guangdong Province is not only good news, it is newsworthy.

 

Guangdong The first H5N6 bird flu patient rehabilitation

(O-Vision) at 19:57 on January 30 2015

(Macau Radio News) Guangdong The first H5N6 bird flu patient rehabilitation, quarantine has been lifted. 59-year-old male patient, on March 4 disease, symptoms of fever and cough, followed by isolation and treatment in Guangzhou, was in critical condition. This is the first case in Guangdong, is also the world's first two confirmed cases of H5N6, the first case case patients from Sichuan, was the death last May. (Liang Shuting Huangcai Chan)

 

While H5N1 and H7N9 are probably still the two avian viruses of greatest concern, the avian flu field has been rapidly expanding the past few years. Over the past year four new avian viruses – H10N8, H5N8, H5N3 & H5N6 – have emerged, and we don’t have a good handle on how much of an impact they will ultimately have.

 

H5N8 has certainly shown the ability to travel well, having already shown up in Europe, North America and Asia, but so far it doesn’t appear to infect humans.   H10N8 and H5N6 have only made a few appearances, but have infected and killed a handful of people. 

 

How all of these viruses will interact (and evolve) is something we are going to have to watch closely over the coming months and years.  For now, the good news is none of these avian viruses appears capable of transmitting efficiently from human to human, and they remain primarily a threat to birds and the poultry industry.

China MOA: H5N6 Outbreak In Hunan Province Poultry

 

# 9629

Although HPAI H5N8 and H5N2 have garnered most of the headlines this fall with their extensive spread out of Asia into Europe and the Pacific Northwest, another freshman virus has been on our radar since last May as well; the H5N6 virus.

 

Unlike H5N8 and H5N2, this emerging virus has already shown some ability to infect humans, with tragic results. We are aware of at least two human cases last year, both fatal (see WHO GAR Update – H5N6 In China).

 

In November of 2014 in FAO-EMPRES Report On The Emergence And Threat Of H5N6, we looked at an analysis of H5N6, and other recently emerged avian flu viruses in China. The previous month, in China: H5 AI Rising, we looked at 24 recent detections of H5N6 across China.

Other than the Guangdong infection in December, we really haven’t heard much since October of last year. Over the weekend, however, China’s MOH announced another outbreak, which occurred about 12 days ago in Hunan Province.

 

Loudi Xinhua County occurred in poultry of highly pathogenic avian influenza

 2015-01-23 17:36:55

Source: Ministry of Agriculture

The Information Office of the Ministry of Agriculture issued January 23, Xinhua County of Loudi City, Hunan Province occurred in poultry of highly pathogenic avian influenza.

January 14, Loudi City, Xinhua County quail farms of suspected bird flu symptoms, onset 5400, died 1200. January 16, animal disease prevention and control center in Hunan diagnosed as suspected bird flu. January 23, by the National Avian Influenza Reference Laboratory confirmed that outbreaks of highly pathogenic avian influenza subtype H5N6 outbreak.

After the outbreak, according to the relevant local plans and control technical specifications, earnestly epidemic disposal work. Have for all 44,160 local poultry were culled and safe disposal. Currently, the outbreaks had been effectively controlled. (Source: Ministry of Agriculture Information Office)

Today, because of this announcement, Hong Kong has announced a ban on imports of poultry and poultry products from the affected area.

 

Import of poultry and poultry products from Xinhua County, Loudi City in Hunan Province, suspended

The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department announced today (January 26) that in view of a notification from the Ministry of Agriculture about a confirmed case of highly pathogenic H5N6 sub-type avian influenza in Xinhua County, Loudi City, Hunan Province, it has followed the existing approach for control of highly pathogenic avian influenza and taken the recommendations from the World Organisation for Animal Health into account to ban the import of poultry and poultry products, including poultry eggs, from the area within a radius of 3 kilometres from the said place for a period of 90 days and from the area within a radius of 13km for 21 days with immediate effect for protection of public health in Hong Kong.

A spokesman for the CFS said that, according to the information from the General Administration of Quality Supervision, Inspection and Quarantine, the outbreak does not affect any registered Mainland poultry farms for export to Hong Kong. No registered poultry meat or poultry egg processing plants are currently situated within the import restriction zone concerned either. According to records, no poultry or poultry products were imported from Hunan Province into Hong Kong between January and November last year.

The Centre will closely monitor the latest developments of the avian flu case in the province and take appropriate follow-up action as necessary.

Ends/Monday, January 26, 2015
Issued at HKT 18:38

 

While not apparently spreading as fast, or as far, as the high-flying H5N8 virus, H5N6 continues to erupt across central China, and like H7N9, poses the risk of future expansion outside of China.

WHO GAR Update – H5N6 In China

Credit Wikipedia

 

# 9503

The avian H5N6 virus, which was only first detected last April in Nanchong City (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu) – where it infected and killed one person and infected local poultry – has expanded its geographic range over the past 8 months and has since been reported in Vietnam and across much of China (see  China: H5 AI Rising).

 

While primarily a concern for poultry producers (see FAO Warns On H5N6), last week we learned of a second human infection in Guangdong Province, China (see China: 2nd Human Case Of H5N6 Reported). 

 

Although it doesn’t add much to what we already knew about this case, today the World Health Organization has posted the following update on that case.  The patient is still listed as being in critical condition. 

 

Human infection with avian influenza A(H5N6) virus – China

Disease outbreak news
28 December 2014

On 23 December 2014, the National Health and Family Planning Commission (NHFPC) of China notified WHO of 1 laboratory-confirmed case of human infection with avian influenza A(H5N6) virus.

Details of the case are as follows

• A 58-year-old male from Guangzhou city, Guangdong Province who developed symptoms on 4 December. He was admitted to hospital on 9 December and is now in critical condition. The patient has history of exposure to live poultry.

The Chinese Government has taken the following surveillance and control measures

• Strengthen surveillance and situation analysis
• Reinforce case management and medical treatment
• Conduct risk communication with the public and release information.

WHO continues to closely monitor the H7N9 situation and conduct risk assessment. So far, the overall risk associated with the H7N9 virus has not changed.

WHO advice

WHO advises that travellers to countries with known outbreaks of avian influenza should avoid poultry farms, or contact with animals in live bird markets, or entering areas where poultry may be slaughtered, or contact with any surfaces that appear to be contaminated with faeces from poultry or other animals. Travellers should also wash their hands often with soap and water. Travellers should follow good food safety and good food hygiene practices.

WHO does not advise special screening at points of entry with regard to this event, nor does it currently recommend any travel or trade restrictions. As always, a diagnosis of infection with an avian influenza virus should be considered in individuals who develop severe acute respiratory symptoms while travelling or soon after returning from an area where avian influenza is a concern.

WHO encourages countries to continue strengthening influenza surveillance, including surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns, in order to ensure reporting of human infections under the IHR (2005), and continue national health preparedness actions.

 

While H5N1 and H7N9 are probably still the two avian viruses of greatest concern, the field has been growing the past few years. Since December of 2013 four new avian viruses – H10N8, H5N8, H5N3 & H5N6 – have emerged, and we don’t have a good handle on how much of an impact they will ultimately have.

 

H5N8 has certainly shown the ability to travel well, having already shown up in Europe and North America, but so far it doesn’t appear to infect humans.   H10N8 and H5N6 are less well traveled, but have infected and killed a handful of people. 

How all of these viruses will interact (and evolve) is something we are going to have to watch closely over the coming months.  For now, the good news is none of these avian viruses appears capable of transmitting efficiently from human to human, and they remain primarily a threat to birds and the poultry industry.

China: 2nd Human Case Of H5N6 Reported

Credit Wikipedia

# 9479

 

 

For the second time this year China is reporting a human infection with the recently emerged H5N6 virus.  You may recall that last May (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu) we saw the first reported poultry outbreak, and human infection with this virus - and since then the virus has been reported in poultry outbreaks both in Vietnam and China.

Last month in FAO-EMPRES Report On The Emergence And Threat Of H5N6, we looked at this, and other recently emerged avian flu viruses in China.

 

Two reports, the first from Xinhua News followed by a statement from Hong Kong’s CHP.

 

Guangdong found one case of human infection with the H5N6 bird flu

At 21:43 on December 23 2014
Source: Xinhua

Guangzhou Xinhua December 23 (Reporter Xiao Sisi) Guangdong Provincial Health and Family Planning Commission briefing on the 23rd, the Guangdong Provincial Health and Family Planning Commission into the winter season in influenza and other respiratory diseases after the high season, influenza, severe pneumonia and other routine monitoring, From one case of severe pneumonia cases were detected positive for H5N6 avian influenza virus nucleic acid. 22, the Chinese Center for Disease Control and Prevention for further review test results for influenza A H5N6 avian influenza virus nucleic acid positive.

December 23, the National Family Planning Health Organization expert consultation and assessment, combined with clinical manifestations of cases, laboratory test results and epidemiological history, the diagnosis of the cases of H5N6 human cases of avian influenza infection. Experts judged believe in this case appears to sporadic cases. All close contacts of cases did not appear abnormal human transmission does not occur.

According to the briefing, the patients were male, 58 years old, currently living in Panyu District, Guangzhou City, had colon surgery performed last year, is currently in critical condition in hospitals in Guangzhou admitted to hospital.

Experts, the influenza virus hemagglutinin is based on the virus surface (H) and neuraminidase (N) to name, which has 16 subtypes H, N has nine subtypes. H5N6 avian influenza is a subtype of avian influenza virus.

 

Notification of confirmed human case of avian influenza A(H5N6) in Guangdong

The Centre for Health Protection (CHP) of the Department of Health (DH) has been notified by the Health and Family Planning Commission of Guangdong Province of a confirmed human case of avian influenza A(H5N6) today (December 23) affecting a 58-year-old man in Guangzhou, Guangdong Province.

The patient, who is in critical condition, is currently receiving treatment in a hospital in Guangzhou. No abnormality was reported among the close contacts of the patient. 

“All novel influenza A infections (including H5N6) are notifiable diseases in Hong Kong," a spokesman for the DH said.

"Locally, we will remain vigilant and work closely with the World Health Organization and relevant health authorities to monitor the latest developments," the spokesman said.

"In view of cases confirmed on the Mainland, members of the public should maintain good personal, food and environmental hygiene at all times during travel," the spokesman urged.

(Continue . . .)

Study: H5 Clade 2.3.4.6 Receptor Binding

# 9460

 

 

Unlike in mammals, where influenza viruses generally produce a respiratory infection, influenza in birds is a gastrointestinal malady. The virus attaches to - and replicates in – the avian gut,  and is spread primarily through infected droppings.

 

As you might imagine, avian flu viruses are well adapted to attack the kind of cells found within the avian intestinal tract; α2,3-linked sialic acid  avian receptor cells.

 

Humans, and many (but not all) mammals have very few α2,3 receptor cells in their upper airway (but do have some deep in the lungs), making it difficult for avian flu viruses to easily attach to, and infect, non-avian species. 

 

When they do jump to humans, it usually results in a serious deep lung infection (pneumonia).

Human, or mammalian adapted flu viruses bind preferentially to a different type of cell - α2,6 receptor cells -  which are abundant in their upper respiratory systems. They are also adapted to replicate in the 5 to 10 degree cooler environment of the upper airway, compared to the intestinal tract of birds.

For an avian influenza virus to successfully jump species and to become a human pandemic threat, these receptor binding and temperature tolerance issues are believed to be two of the biggest hurdles.  There are likely others, but these two appear to top the list.

 

As avian viruses jump (even tentatively) to other species, it gives them a chance to produce host adaptations;  mutations that favor survival in their new environment. The more jumps, the more opportunities the virus has (through trial and error)  to `figure out’  what evolutionary changes are needed to make the new species a suitable host.

 

Viruses also change slowly through antigenic drift, even in their native hosts, and can abruptly change through antigenic shift – or reassortment.  Shift occurs when two flu viruses inhabit the same host at the same time, swap genetic material, and produce a `hybrid’ strain.  

Birds, swine, humans . . .  in fact almost any flu susceptible species – can act as a mixing vessel.  While pandemic viruses are rare, as any virologist will tell you . . . Shift happens.

 

While we are justifiably concerned over the recently emerged H7N9 virus given its track record over the past couple of years, the avian flu virus with the longest resume and greatest diversity is H5N1 and its recently emerged cousins; H5N8, H5N6, H5N3.  This virus has been around for 18 years, and has gone from a single clade discovered in 1996 to a diverse, and growing constellation of clades, sub-clades, and variants within sub-clades.

 

The following chart from the World Health Organization hints at just how much diversity the virus acquired over its first 15 years..

(click to load larger image)  (Note: Chart only goes through 2011)

 

Until a year or so ago, most H5N1 clades were classified by 3 digit identifiers, such a clade 2.3.4.

But in 2013, researchers reported on Novel Variants of Clade 2.3.4 Highly Pathogenic Avian Influenza A(H5N1) Viruses, China, and suggested that `these groups should be assigned new fourth-order clades of 2.3.4.4, 2.3.4.5, and 2.3.4.6 to reflect the wide divergence of clade 2.3.4 viruses.’

 

In short order, we saw the emergence of several new H5 subtypes (through reassortment), all carrying the newly identified H5 clade 2.3.4.6 HA gene segment, including the recent high flying H5N8 and H5N6 subtypes. The graphic below (produced before H5N8 showed up in Europe and North America) illustrates their recent geographic spread in Asia comes from the November FAO-EMPRES Report On The Emergence And Threat Of H5N6).

 

While there are a lot of H5 clades out there, and more will invariably appear, right now clade 2.3.4.6 is making a lot of noise.   So the open access study, published this week in the Journal Veterinary Research, that looks at the receptor binding qualities of this new clade is of particular interest.

 

While many will want to read the entire report, I’ve excepted some highlights below.

 

In short, they determined that this new clade binds to both avian α2,3  and mammalian α2,6 receptor cells, and that at least one (of 4 tested) strains replicated well, and transmitted efficiently, in test guinea pigs.

 

Novel H5 clade 2.3.4.6 viruses with both α-2,3 and α-2,6 receptor binding properties may pose a pandemic threat

Qunhui Li¹, Xuan Wang¹, Min Gu¹², Jie Zhu¹, Xiaoli Hao¹, Zhao Gao¹, Zhongtao Sun¹, Jiao Hu¹², Shunlin Hu¹², Xiaoquan Wang¹², Xiaowen Liu¹² and Xiufan Liu^12*

Abstract

The emerging H5 clade 2.3.4.6 viruses of different NA subtypes have been detected in different domestic poultry in China. We evaluated the receptor binding property and transmissibility of four novel H5 clade 2.3.4.6 subtype highly pathogenic avian influenza viruses. The results show that these viruses bound to both avian-type (α-2,3) and human-type (α-2,6) receptors. Furthermore, we found that one of these viruses, GS/EC/1112/11, not only replicated but also transmitted efficiently in guinea pigs. Therefore, such novel H5 subtype viruses have the potential of a pandemic threat.

<SNIP>

Discussion

Historically, changes in the receptor binding protein of influenza virus, HA, have been implicated in the initiation of a pandemic. It has been established for the H1N1 (1918), H2N2 (1957) and H3N2 (1968) pandemic viruses that a change in HA protein from a preference for α-2,3-linked sialic acids (avian receptor) to a preference for α-2,6-linked sialic acids (human receptor) is a prerequisite for efficient transmission of avian viruses to humans [10].

H5 HPAIV pose a serious pandemic threat due to their virulence and high mortality in humans, and their increasingly expanding host reservoir and significant ongoing evolution could enhance their human-to-human transmissibility. Recently, novel clade 2.3.4.6 H5 HPAIV with various NA subtypes (H5N1, H5N2, H5N6, and H5N8) were reported in Eastern China and South Korea [2]-[7],[9],[15].

Here, we evaluated their receptor specificity and transmission in guinea pigs. The results show that the viruses bound to both avian-type (α-2,3) and human-type (α-2,6) receptors. In humans, the α-2,6 receptor is expressed mainly in the upper airway, while the α-2,3 receptor is expressed in alveoli and the terminal bronchiole [16].

A virus with good affinity to both α-2,3 and α-2,6 receptors may especially be harmful, as it could infect efficiently via its binding to α-2,6 receptors in the upper airway and simultaneously cause severe infection in the lung via its binding to α-2,3 receptors. And this hypothesis is supported by the fact that one of the two well-characterized HA genes from the H1N1 1918 pandemic virus binds efficiently to both α-2,3 and α-2,6 receptors [17]. In addition, previous studies showed that the human-infecting novel H7N9 and the latest reassortant H10N8 avian influenza viruses yet have substantial affinity to both avian-type (α-2,3) and human-type (α-2,6) receptors [18],[19].

Sequence analysis showed that novel H5 (HPAIV) clade 2.3.4.6 simultaneously carry a T160A mutation which results in the lack of an oligosaccharide side chain at 158–160 of HA, and it is critical for the H5 subtype influenza viruses tested to bind to human-like receptors and to transmit among a mammalian host [20],[21]. Whether this T160A variation affects the receptor-binding property deserves further investigation.

Previous studies showed that some H5 subtype influenza viruses can transmit efficiently in guinea pigs [21]. In this study, we also found that one of these viruses, GS/EC/1112/11, not only replicated but also transmitted efficiently in guinea pigs. These findings emphasize that continued circulation of these viruses may pose health threats for humans. Therefore, we need to intensify our effort to detect such viruses as early as possible.

(Continue . . .. )

 

 

Although there are likely other inhibiting factors stopping this H5 clade 2.3.4.6 strain (and others) from sparking a pandemic, this dual binding ability would appear to move this particular clade a little closer towards it becoming a potential global health threat.  

 

That said, it should be noted that in 2013 we saw a similar finding with the H7N9 virus (see NEJM Journal Watch: Characteristics of H7N9), but that virus still has not displayed the ability to spread efficiently from human-to-human.

Despite our continual gains in knowledge regarding influenza viruses, we obviously don’t know all of the factors involved in turning an avian influenza virus into a `humanized’ one.  But studies like this one may help us recognize an impending threat, and give us enough warning time to prepare our defenses (i.e. vaccines, antivirals, etc.).

For more on the evolution of H5 and H7 viruses, you might wish to revisit:

 

Nature Comms: Host Adaptation Of Avian Influenza Viruses

EID Journal: Potential Human Adaptation Mutation of Influenza A(H5N1) Virus, Canada

PLoS: Human-Type H5N1 Receptor Binding In Egypt

H5N6 Resurfaces In Vietnam

  

Credit Wikipedia 

 

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While H5N8 popping up in Germany, the Netherlands, the UK, Japan, and now Italy has garnered most of the avian flu headlines over the past six weeks, H5N6 – the other newly emerged HPAI H5 virus of 2014 (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu) – hasn’t gone away. 

 

Unlike H5N8, which to date has not been reported to have infected humans - H5N6 has a track record of infecting, and killing, at least one person.

 

Reports of H5N6 this fall have been sporadic, with China notifying the OIE of a couple of dozen outbreaks in poultry in October (see China: H5 AI Rising), and a half dozen or so reports also coming out of Vietnam (see FAO Warns On H5N6). 

 

Six weeks ago – before the sudden and unexpected arrival of H5N8 in Europe – H5N6 was considered the `one to watch’  (see FAO-EMPRES Report On The Emergence And Threat Of H5N6).

 

Perhaps more accurately, one of six to watch, as we’ve added five new Highly Pathogenic Avian Flu subtypes in less than 2 years; H7N9, H5N6, H5N8, H5N3, and H10N8. 

The sixth viral horseman in this poultry apocalypse being the venerable H5N1 virus, which continues to infect birds, poultry, and occasionally humans in Asia and the Middle East.

All of which brings us to the latest report of an outbreak of H5N6 in the central Vietnam province of Quang Ngai.

 

Quang Ngai canceled 12,000 quails were infected with influenza A / H5N6

Dinh Thi Huong (VNA / Vietnam +) at: 18/12/14 15:01

Artwork. (Source: Dinh Hue / VNA)

In the morning of 18/12, the Steering Committee of disease prevention cattle, poultry Son Tinh district (Quang Ngai) was carried out to destroy the entire 12,000 quails were infected with influenza A / H5N6 family of Pham Hoang Diep (team 8, Loc Lam Village North, Ha Tinh, Son Tinh district). Pham Hoang Diep said his family lay eggs, quail farming, including 10,000 children were seven months old, and 45 days of age and 2,000 children were vaccinated Room vaccine regulations.

However, the last 14/12 days, Diep discovered many quail died of unknown causes. He told officers Veterinary Station Ha Tinh and Son Tinh district. Immediately after receiving the notice, the veterinary station officials have sent samples to the Veterinary Authority the 4 tests. Test results showed that the male quail Diep infected with influenza A / H5N6.

Steering Committee for prevention of animal disease, avian Son Tinh District has conducted the entire destruction of 12,000 quail Diep. Agency mailings y 4 in Da Nang area also has to check and monitor the implementation of measures of disinfection, sterilization and disposal of the body dead poultry in his household to control Scallops source of the epidemic spreading.

To prevent the spread of the disease across the board, steering committee for animal disease prevention poultry Son Tinh district has directed the officials veterinary station urgently spraying, spreading lime to disinfect cages farms throughout the district. outbreak of Pham Hoang Diep family's flu outbreak A / H5N6 occurred Thursday in the province of Quang Ngai. Currently, the Steering Committee of disease prevention poultry Quang Ngai province continues to closely monitor outbreaks, detect and treat if detected a new outbreak; and implement measures to prevent influenza A / H5N6 to humans. /.

 

Given the limits of surveillance and reporting across much of China and  other parts of Asia, it is likely that outbreaks of H5N6 – as well as other avian flu varieties– are underreported.

 

Although only reported thus far in China and Vietnam, as I wrote last month in Bird Flu Spread: The Flyway Or The Highway?, these avian viruses have a habit of disseminating themselves across a wide geographic area, often aided and abetted by migratory and wild birds, legal or illegal transport of poultry or poultry products, or other man-made devices.

Major Global Migratory Flyways – Credit FAO

 

In March of 2013, in a case of unusually good timing, we looked at a study that selected East-Central China a one of the top hotspots in the world for the creation of zoonotic influenza viruses – those that can jump from animals to man (see EID Journal: Predicting Hotspots for Influenza Virus Reassortment).

Two weeks later China announced the discovery of the H7N9 virus, followed over the next 18 months by the emergence of H10N8, H5N8, H5N6, and H5N3.

While most of these viruses are likely to remain a threat primarily to poultry and wild birds, scientists take the threat posed by any emerging novel influenza virus seriously.  And given this recent rapid expansion of HPAI subtypes, one shouldn’t be terribly surprised to see this trend continue, and have new subtypes emerge in the months or years to come.

FAO-EMPRES Report On The Emergence And Threat Of H5N6

 

# 9305

 

For many years Southeast Asia has been considered `the cradle of influenza’, an area of the world where both human and animal influenza viruses circulate more-or-less year round, and where humans and farm animals often live in close proximity with one another.

 

In March of 2013, in EID Journal: Predicting Hotspots for Influenza Virus Reassortment, we looked at a study that selected East-Central China a one of the top hotspots in the world for the creation of zoonotic influenza viruses – those that can jump from animals to man. 

And then, almost on cue, two weeks later we saw the first reports of a new avian flu virus that had jumped to humans in Shanghai; H7N9.  

 

In a matter of less than 60 days, more than 130 human cases were diagnosed.  The following year -  another 320+ cases were tallied, and over the summer we saw the following assessment appear in Eurosurveillance: Genetic Tuning Of Avian H7N9 During Interspecies Transmission.

Overall, due to the genetic tuning procedure, the potential pandemic risk posed by the novel avian influenza A(H7N9) viruses is greater than that of any other known avian influenza viruses.

As if that weren’t enough,  in rapid succession over the past 12 months we’ve seen 3 more subtypes appear:

 

• Last winter we saw a new H10N8 infect three in China (see  Jiangxi Province Reports 3rd H10N8 Case)
• In January of 2014 a major outbreak of a newly emerging H5N8 virus struck South Korean Poultry (see EID Journal: Describing 3 Distinct H5N8 Reassortants In Korea) and last week showed up in Germany.
• And In April a newly emerging H5N6 killed a man in Southern China, and has now been seen spreading in both Chinese and Vietnamese poultry (see FAO Warns On H5N6)

Suddenly, we’ve gone from having 1 worrisome bird flu virus (H5N1), to having at least 5 (H5N1, H7N9, H10N8, H5N8, H5N6).  All are the product of reassortment – the swapping of gene segments between two flu viruses - to produce a new hybrid.

 

Although categorized by their two surface proteins (HA & NA) Influenza A viruses have 8 gene segments (PB2, PB1, PA, HA, NP, NA, M1, M2, NS1, NS2).

Shift, or reassortment, happens when two different influenza viruses co-infect the same host swap genetic material.  New hybrid viruses may be the result of multiple reassortments, with gene contributions coming from several parental viruses.

 

Interestingly, while their HA and NA genes may differ – almost all of these new viral interlopers carry the internal genes from the avian H9N2 virus (see The Lancet: H9N2’s Role In Evolution Of Novel Avian Influenzas). 

 

And while we are talking about 5 main subtypes (for now, anyway), we’ve seen evidence of dozens of variants or clades bubbling up within these subtypes  - with new, updated versions emerging at a tremendous rate.

 

And new subtypes continue to emerge, as is evidenced by the announcement last month that an H5N3 virus was detected in a live bird market in Changsha, Hunan. 

 

The more subtypes in circulation, the more `interchangeable parts’  that are available for building new viruses. No one should be overly shocked if this list of newly emergent avian viruses continues to grow this winter. 

 

All of which brings us to a new 5-page FAO EMPRES report published today, excerpts which I’ve posted below.  By all means, download the entire PDF, as it is chock full of good information and covers the genesis – and possible interaction with – other avian influenza viruses in the region (i.e. H7N9, H10N8, H5N8, etc.).

 

Avian influenza A(H5N6): the latest addition to emerging zoonotic avian influenza threat In East and Southeast Asia

VOL 30 — NOVEMBER 2014 EMPRES-ANIMALHEALTH@FAO.ORG | WWW.FAO.ORG/AG/EMPRES.HTML

<BIG SNIP>

Perspectives and recommendations
The epidemiological and genetic analysis described above show that the virus is still more adapted to avian-type than  human-type respiratory receptors. However, with winter season approaching in eastern Asia, the prevalence of the virus in poultry is expected to rise, increasing both chances for human exposure and opportunities for mutation or reassortment, especially considering the location of circulation of this virus: in endemic regions with H5N1, H9N2 and H7N9 for China. The latter could change the viruses’ transmissibility to humans. H5N6 therefore remains a public health threat, which requires close monitoring in the same way as for H5N1 HPAI and H7N9.

The possibility exists that wild birds could become infected and spread these viruses to other countries or continents. Migratory birds, which have played a key role in the introduction of H5N1 to Europe and Africa [Kilpatrick et al, 2006] and of H5N8 to the Republic of Korea [Jeong et al, 2014], could spread the viruses to other countries or continents. Research is required to better understand the role migratory birds play in the epidemiology of these novel viruses and related risks.

(Continue . . . .)

 

For those who may have missed it, coincidentally I wrote about concerns over the spread of H5N6, H7N9, H5N8 and other avian flu viruses this morning in Bird Flu Spread: The Flyway Or The Highway?

FAO Warns On H5N6

Photo Credit – FAO

 

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Last April a new strain of HPAI H5N6 appeared in poultry, killing one person in Nanchong City (see Sichuan China: 1st Known Human Infection With H5N6 Avian Flu).  Once the threat was identified, local poultry was culled, and we heard nothing more for several months.

 

While Low Pathogenic H5N6 had been identified previously in wild birds  in Taiwan, Germany, Sweden and the United States this new strain was classified as highly pathogenic. 

 

And like the H5N8 virus which emerged last January and ravaged South Korea’s poultry industry throughout the spring, this new virus was a reassortant of the H5N1 avian flu virus (see Whole-Genome Sequence Of Reassortant H5N6 Avian Virus).

 

All was quiet on the H5N6 front until early August, when the virus showed up in widely separated outbreaks in central and northern Vietnam (see OIE: Two Outbreaks Of H5N6 In Vietnamese Poultry).

 

In short order we began to see additional outbreaks in Vietnam (see Vietnam Gears Up To Detect, Fight Avian H5N6) and two thousand miles away in northern China (see China: H5N6 Outbreak In Heilongjiang Poultry).

 

Last week, the central Vietnamese Quang Ngai province reported their fourth outbreak in just over a month, and over the weekend Vietnamese media have reported that a massive cull is underway (see A/H5N6 flu virus: Quang Nam culls 800,000 ducks).

 

While its threat to humans is uncertain, the threat to the poultry industry – and to the the food security and meager incomes of households that raise subsistence poultry – could be dire. 

 

After a decade of losses due to H5N1, and the recent introduction of the stealthy H7N9 virus, the last thing anyone wanted to see in that part of the world is another avian flu threat.  As if that weren’t enough, South Korea’s H5N8 virus – which briefly made it to Japan last spring – could also make further inroads across Asia this fall and winter.

 

Today the FAO released the following news article on their website.  Excerpts follow, and I’ll have  a bit more when you return.

 

Increased concern over latest strain of avian influenza in Southeast Asia

FAO urges continued vigilance to safeguard poultry and livelihoods

22 September 2014, Rome - A recently-emerged strain of avian influenza virus in poultry in Southeast Asia known as A(H5N6) represents a new threat to animal health and livelihoods and must be closely monitored, FAO said today.
Chinese authorities first reported the influenza A(H5N6) virus in poultry in April 2014. Since then, the Lao People's Democratic Republic and Viet Nam have also detected the H5N6 virus in poultry.

"Influenza viruses are constantly mixing and recombining to form new threats," said FAO's Chief Veterinary Officer, Juan Lubroth. "However, H5N6 is particularly worrisome, since it has been detected in several places so far from one another, and because it is so highly pathogenic, meaning infected poultry quickly become sick and, within 72 hours, death rates are very high."

The fact that the virus is highly virulent in chickens and geese and potentially spread across a large part of Southeast Asia translates into a real threat to poultry-related livelihoods. Poultry contributes to the incomes of hundreds of millions of people throughout the subregion.

The World Organisation for Animal Health (OIE), which works together with FAO and the World Health Organization (WHO) to support countries' responses to animal and human disease threats, is also monitoring the situation closely.

"An effective surveillance and an early detection of animal disease at source are two main keys to reduce the risk of dissemination and to ensure safe trade. The OIE calls on its 180 member countries to respect their commitment and to immediately notify on WAHIS any outbreak detected on their territory," said OIE Director-General Bernard Vallat.

Limited threat to human health

Only one case of H5N6 has been reported in humans after contact with exposure to poultry shortly after its detection in China. The person later died. There have been no other human cases.  Though the scientific community is still in the process of understanding the dynamics of this new strain, it is unlikely that H5N6 represents an immediate and significant threat to human health.

"Current evidence suggests H5N6 poses a limited threat to human health at this stage," said WHO epidemiologist Elizabeth Mumford. "It's been detected in multiple places in poultry, yet we only have one human infection reported. This suggests that the virus does not easily jump from animals to humans. Of course, we still need to remain vigilant, because prevalence in poultry and therefore human exposure could increase during the winter."

Even if the public health risks posed by H5N6 currently appears to be low, other pathogens, including other subtypes of influenza viruses such as H5N1 and H7N9, still can present cause for concern. FAO and WHO recommend consumers follow appropriate hygiene, food preparation and food safety guidelines. These include: washing hands often, cleaning utensils and surfaces used during food preparation, and eating only well-cooked poultry meat products. People should also avoid handling sick birds or those that have died of illness.

FAO and WHO are stressing that at this time it is critical for countries in Southeast and East Asia -- especially those with links to poultry production and trade -- to ramp up efforts to detect and report influenza viruses in poultry and monitor for any human infections.

(Continue . . . )

 

 

Although Southeast Asia has long been known as the `cradle of influenza’ -  an area of the world where both human and animal influenza viruses circulate in close proximity more-or-less year round and can occasionally serve up hybrids – the past couple of years has seen a remarkable number of reassortants appear.

 

H7N9, H5N6, H5N8, H10N8, H6N1 . . . .  all with a increasing number of clades, as well.

Of these, H7N9 has provoked the most concern by far, as it has sparked two sizable human waves of infection, and is expected to return when temperatures cool this fall and winter.  But H10N8 is no slouch, having killed three people in China last winter, while the others are too new to really evaluate their public health impact.

 

The good news is that reassortant viruses with genuine pandemic potential only appear very rarely. 

 

The bad news is that nature’s laboratory is open 24/7, and it is constantly trying to produce the next `successful’ virus.  And the more subtypes it has to play with, the greater the odds are it will come up with something we really don’t want to have to deal with.

 

All of which highlights the need for continual and enhanced surveillance of humans, livestock, and wild birds for emerging viral threats. Because it isn’t a question of if another pandemic will emerge.

 

It’s really just a matter of when.