avianinfluenza.org

Avian Influenza Mutation, H5N1

Updated: Thursday, August 21, 2014 2:58 PM EDT
Avian influenza Articles
Preparing for Human, H5N1 bird flu outbreak
Bird flu symptoms
Can you catch Bird Flu , Avian Influenza from eating poultry?
Confirmed human H5N1 bird flu cases
The origins of Bird Flu
Your cat and Bird flu , avian influenza
Potential bird flu treatment discovery
Bird flu , Avian influenza, new Spanish flu of 1918?
Bird Flu scare and the US bird Embargo
Bird flu , Avian Influenza a non-technical view
Bird flu , Avian flu outbreaks (human to human) in North America
Bird flu , Avian Influenza virus in Smuggled Thai Eagles
Bird flu , Avian Influenza Mutation H5N1 Virus
H5N1 Bird flu , Avian Influenza human vaccine developments
Bird flu , Avian influenza, fact or fiction?
Economic and Social Impacts of Bird Flu , Avian Influenza
Preparing For Pandemic Influenza
Bird Flu , Avian Influenza FAQ
Trial of Experimental Bird Flu , Avian Influenza Vaccine
Bird flu , Avian Influenza infection in Humans
Bird Flu , Avian Influenza explained

Bird Flu Map Links
USGS Interactive Bird flu map
Whooper Swan Tracking Map
Bird flu - US Government

Avian Influenza Mutation, H5N1

H5N1 is a type of avian influenza virus (bird flu virus) that has mutated through antigenic drift into dozens of highly pathogenic varieties. The first of these appeared in China in 1996 in birds and in Hong Kong in 1997 in Humans.

This infection of humans coincided with an epizootic (an epidemic in nonhumans) of H5N1 influenza in Hong Kong's poultry population. This panzootic (a disease affecting animals of many species esp. over a wide area outbreak was stopped by the killing of the entire domestic poultry population within the territory. The name H5N1 refers to the subtypes of surface antigens present on the virus: hemagglutinin type 5 and neuraminidase type 1.

Influenza A virus, the virus that causes Avian flu. Transmission electron micrograph of negatively stained virus particles in late passage. (Source: Dr. Erskine Palmer, Centers for Disease Control and Prevention Public Health Image Library).
Influenza A virus, the virus that causes Avian flu. Transmission electron micrograph of negatively stained virus particles in late passage. (Source: Dr. Erskine Palmer, Centers for Disease Control and Prevention Public Health Image Library).
Colorized transmission electron micrograph of H5N1 (golden) grown in Madin-Darby canine kidney cells (green). (Source: C. Goldsmith, J. Katz and S. Zaki. Centers for Disease Control & Prevention Public Health Image Library. Image #1841.).
Colorized transmission electron micrograph of H5N1 (golden) grown in Madin-Darby canine kidney cells (green). (Source: C. Goldsmith, J. Katz and S. Zaki. Centers for Disease Control & Prevention Public Health Image Library. Image #1841.).

As of November 1, 2005, 122 cases of infections in humans, resulting in 62 deaths, have been confirmed outside of China (see Human cases). Thirteen countries across Asia and Europe have been affected. Additionally, more than 120 million birds have died from infection or been killed to prevent further infections.

Transmission and infection

Infected birds pass on H5N1 through their saliva, nasal secretions, and feces. Other birds may pick up the virus through direct contact with these excretions or when they have contact with surfaces contaminated with this material. Because migratory birds are among the carriers of the H5N1 virus it may spread to all parts of the world. Past outbreaks of avian flu have often originated in crowded conditions in southeast and east Asia, where humans, pigs, and poultry live in close quarters. In these conditions a virus can mutate into a form that more easily infects humans.

The majority of H5N1 flu cases have been reported in southeast and east Asia. Once an outbreak is detected, local authorities often order a mass slaughter of birds or animals affected. If this is done promptly, an outbreak of avian flu may be prevented. However, the United Nations (UN) World Health Organization (WHO) has expressed concern that not all countries are reporting outbreaks as completely as they should. China, for example, is known to have officially denied past outbreaks of severe acute respiratory syndrome (SARS) and HIV.

H5N1 infections in humans are generally caused by bird to human transmission of the virus. A few isolated cases of suspected human to human transmission exist, but there is no proof either way in those cases.

Prevention

The current method of prevention in animal populations is to destroy infected animals as well as animals suspected of being infected. In southeast Asia, millions of domestic birds have been slaughtered to prevent the spread of the virus.

The probability of a "humanized" form of H5N1 emerging through recombination in the body of a human co-infected with H5N1 and another influenza could be reduced by influenza vaccination of at-risk workers. It is not clear at this point whether vaccine production could be stepped up sufficiently to meet this demand.

If an outbreak of pandemic flu does occur, its spread might be slowed by increasing hygiene in aircraft, and by examining airline cabin air filters for presence of H5N1 virus.

The American Centers for Disease Control and Prevention advises travelers to areas of Asia where outbreaks of H5N1 have occurred to avoid poultry farms and animals in live food markets[2]. Travelers should also avoid surfaces that appear to be contaminated by feces from any kind of animal, especially poultry.

There are several H5N1 vaccines for several of the H5N1 varieties. H5N1 continually mutates rendering them, so far for humans, of little use.

Symptoms

Since H5N1 is an influenza virus, symptoms similar to those of the common flu, such as fever, cough, sore throat, and sore muscles, can develop in infected humans. However, in more severe cases, pneumonia and respiratory failure can develop and eventually cause death. Patients with H5N1 avian influenza have rarely had conjunctivitis[3], unlike human cases of infection by the H7 virus.

"The H5N1 virus causes an exaggerated response of cytokines (such as TNF-a), and this could result in a toxic-shock-like syndrome (including fever, chills, vomiting and headache), which ultimately results in death "In many diseases (including H5N1 in humans), a 'cytokine storm' [also called hypercytokinemia (sometimes spelled hypercytokinaemia)] is triggered by the infection. Cytokines are hormones that regulate the immune sytem. When released at the right time in the proper amounts, cytokines can help fight infections and regulate processes through out the body. But many cytokines are inflammatory and are damaging to the body if present in too high levels, or for too long. [...] But whatever it is called, this phenomenon is a type of inflammatory cascade. [...] Many inflammatory cascades have self limiting components - the release of an inflammatory agent often leads to the production of both anti-inflammatory and inflammatory compounds. But as microbes evolve, they sometimes begin producing a mix of toxins that interfere with the control mechanisms of the immune system. This seems to be the case for the deadly strains of avian influenza. The H5N1 virus is not only partially resistant to the cytokines that are involved in fighting viruses, but it also reduces the production of anti-inflammatory cytokines - in essence, it enhances the accelerator while impairing the brakes, and the immune system goes out of control and crashes."

Treatment

"The 3 viral envelope proteins of influenza A virus are most medically relevant. The hemagglutinin (HA), neuraminidase (NA), and M2 are essential viral proteins targeted by host antibodies or antiviral drugs such as oseltamivir and rimantadine (46). The HA glycoprotein forms spikes at the surface of virions, mediating attachment to host cell sialoside receptors and subsequent entry by membrane fusion. The NA forms knoblike structures on the surface of virus particles and catalyzes their release from infected cells, allowing virus spread. The M2 is a transmembrane protein that forms an ion channel required for the uncoating process that precedes viral gene expression."

Neuraminidase inhibitors are a class of drugs which act on a protein conserved in all influenza A viruses. Drugs of this type include zanamivir and oseltamivir, the latter being licensed for prophylaxis treatment in the United Kingdom. Oseltamivir, which "attacks the influenza virus and stops it from spreading" inside the user's body [7], is marketed by Roche as Tamiflu, and this brand has become the drug of choice for governments and organizations in their preparations for a possible H5N1 pandemic. In August 2005, Roche agreed to donate three million courses of Tamiflu to the World Health Organization, to be deployed by the WHO to contain a pandemic in its region of origin. Although Tamiflu is patented, international law gives governments wide freedom to issue compulsory licenses for life-saving drugs.

A further class of drugs, which include amantadine and rimantadine, target M2 protein, a proton channel found in the viral membrane. Unlike zanamivir and oseltamivir, these drugs are inexpensive and widely available and the WHO had initially planned to use them in efforts to combat a H5N1 pandemic. However, the potential of these drugs was considerably lessened when it was discovered that farmers in China has been administering amantadine to poultry with government encouragement and support since the early 1990s, against international livestock regulations; the result has been that the strain of the virus now circulating in South East Asia is largely resistant to the medication and hence significantly more dangerous to humans[8]. However, the strain of H5N1 spread throughout Northern China, Mongolia, Kazakhstan, Russia and Europe by wild birds in the summer of 2005 is not amantadine resistant.

Mutations and strains

"The influenza virus genome has remarkable plasticity because of a high mutation rate and its segmentation into 8 separate RNA molecules. This segmentation allows frequent genetic exchange by segment reassortment in hosts co-infected with 2 different influenza viruses."

In July 2004, researchers led by H. Deng of the Harbin Veterinary Research Institute, Harbin, China and Professor Robert Webster of the St Jude Children's Research Hospital, Memphis, Tennessee, reported results of experiments in which mice had been exposed to 21 isolates of confirmed H5N1 strains obtained from ducks in China between 1999 and 2002. They found "a clear temporal pattern of progressively increasing pathogenicity" Results reported by Dr. Webster in July 2005 reveal further progression toward pathogenicity in mice and longer virus shedding by ducks.

In May 2005, the occurrence of avian influenza in pigs ("swine flu") in Indonesia was reported. Along with the continuing pattern of virus circulation in poultry, the occurrence in swine raises the level of concern about the possible evolution of the virus into a strain capable of causing a global human influenza pandemic. Health experts say pigs can carry human influenza viruses, which can combine (i.e. exchange homologous genome sub-units by genetic reassortment.) with the avian virus, swap genes and mutate into a form which can pass easily among humans.

In July 2005, a death in Jakarta was the first confirmed human fatality in Indonesia. The deaths of two children, neither of whom were reported to have had close contact with poultry, further raised concerns of human-to-human transmission. [11] As of July 2005, most human cases of avian influenza in East Asia have been attributed to consumption of diseased poultry. Person-to-person transmission has not been unequivocally confirmed in the outbreaks in East Asia.

On August 3, 2005, the WHO said it was following closely reports from China that at least 38 people have died and more than 200 others have been made ill by a swine-borne virus in Sichuan Province. Sichuan Province, where infections with Streptococcus suis have been detected in pigs in a concurrent outbreak, has one of the largest pig populations in China. The outbreak in humans has some unusual features and is being closely followed by the WHO. At that time, Chinese authorities say they have found no evidence of human-to-human transmission . On September 29, 2005, David Nabarro, the newly appointed Senior United Nations System Coordinator for Avian and Human Influenza, warned the world that an outbreak of avian influenza could kill 5 to 150 million people. Also, due to a bipartisan effort of the United States Senate, $4 billion dollars was appropriated to develop vaccines and treatments for Avian influenza.

In 2004 and 2005, 118 people are known to have been infected with the H5N1 virus and 61 of them died. The mortality rate of this virus is as high as that of the virus H1N1 that caused the Spanish Flu of 1918, which killed over 20 million people world wide. One of the major differences between H1N1 of 1918 and the current H5N1 is the fact that the latter is not (yet) transmissible between humans. Until recently, that prevented the H5N1 virus from becoming a pandemic. Recent research of Taubenberger et al {Taubenberger JK, Reid AH, Lourens RM, Wang R, Jin G, Fanning TG. Characterization of the 1918 influenza virus polymerase genes. Nature. 2005 Oct 6;437(7060):889-893} showed that the 1918 virus like H5N1 was an avian virus. Furthermore, Tumpey and colleagues {Tumpey TM, Basler CF, Aguilar PV, Zeng H, Solorzano A, Swayne DE, Cox NJ, Katz JM, Taubenberger JK, Palese P, Garcia-Sastre A. Characterization of the reconstructed 1918 Spanish influenza pandemic virus. Science. 2005 Oct 7;310(5745):77-80} who reconstructed the H1N1 virus of 1918 come to the conclusion that it is especially the polymerase genes and the HA and NA genes that caused the extreme virulence of this virus. The sequences of the polymerase proteins (PA, PB1, and PB2) of the 1918 virus and subsequent human viruses differ by only 10 amino acids from the avian influenza viruses. Human forms of seven of the ten amino acids have already been identified in currently circulating H5N1. It is not unlikely that also the other mutations eventually will surface and make the H5N1 virus better suited for human-to-human transmission. Another important factor is the change of the HA protein to a binding preference for alpha 2,6 sialic acid (the major form in the human respiratory tract). In avian virus the HA protein preferentially binds to alpha 2,3 sialic acid, which is the major form in the avian enteric tract. It has been shown that only a single amino acid change can result in the change of this binding preference. Altogether it seems that only a few mutations are needed to make the H5N1 avian influenza virus a pandemic virus like the one of 1918.

"In Vietnam, scientists at the Ho Chi Minh Pasteur Institute who have been studying the genetic make up of H5N1 samples taken from people and poultry said it had undergone several mutations. 'There has been a mutation allowing the virus to (replicate) effectively in mammal tissue and become highly virulent,' the institute said on its Web site at www.pasteur-hcm.org.vn."

Global spread 2004/2005

Bird Flu Spread on October 26th, 2005
avian influenza Spread on October 26th, 2005

Avian/human cases, Asia

In January 2004, a major new outbreak of H5N1 surfaced in Vietnam and Thailand's poultry industry, and within weeks spread to ten countries and regions in Asia, including Indonesia, South Korea, Japan and mainland China. Intensive efforts were undertaken to slaughter chickens, ducks and geese (over forty million chickens alone were slaughtered in high-infection areas), and the outbreak was contained by March, but the total human death toll in Vietnam and Thailand was twenty three people.

In July 2004, fresh outbreaks in poultry were confirmed in Ayutthaya and Pathumthani provinces of Thailand, and Chaohu city in Anhui, China.

In August 2004, avian flu was confirmed in Kampung Pasir, Kelantan, Malaysia. Two chickens were confirmed to be carrying H5N1. As a result Singapore has imposed a ban on the importation of chickens and poultry products. Similarly the EU has imposed a ban on Malaysian poultry products. A cull of all poultry has been ordered by the Malaysian government within a 10km radius of the location of this outbreak. These moves appear to have been successful and since then, Singapore has lifted the ban and Malaysia has requested the OIE declare Malaysian poultry avian influenza free .

An outbreak of avian influenza in January 2005 affected thirty three out of sixty four cities and provinces in Vietnam, leading to the forced killing of nearly 1.2 million poultry. Up to 140 million birds are believed to have died or been killed because of the outbreak.

Vietnam and Thailand have seen several isolated cases where human-to-human transmission of the virus has been suspected. In one case a young girl, who received the disease from a bird, was held by her mother for roughly five days until she died. Shortly afterwards, the mother also died. In March 2005, it was revealed that two nurses who had cared for avian flu patients had tested positive for the disease.

In July 2005, a death in Jakarta was the first confirmed human fatality in Indonesia. The deaths of the man's two children, neither of whom were reported to have had close contact with poultry, further raised concerns of human-to-human transmission (although infection by eating undercooked poultry may be a more likely explanation) [16]. As of July 20, the outbreak had claimed at least fifty eight human lives mostly in Vietnam. What concerns health researchers now is that the virus mortality rate in Vietnam has dropped significantly lately, from more than 65% to about 35% in a year. This might be a sign that the virus is able to infect a larger number of people (i.e., the virus is able to spread more easily) and possibly develop into a global pandemic with millions of deaths despite the lower reported percentage of deaths. For example, the mortality rate of 1918 Spanish flu (H1N1) pandemic was less than 5% . Also, in July 2005, it was confirmed H5N1 had appeared in Russia's Novosibirsk region, probably carried by migratory birds .

On July 28, avian influenza was reported to have killed two more people in Vietnam, raising the death toll to sixty . As of July 2005, most human cases of avian influenza in East Asia have been attributed to consumption of diseased poultry. Person-to-person transmission has not been unequivocally confirmed in the outbreaks in East Asia.

Asia and beyond

Also in early August, an avian outbreak of H5N1 flu was confirmed in Kazakhstan and Mongolia, suggesting further spread of the virus . Later in August, the virus was found in western Russia, marking its appearance in Europe. As a result, Dutch authorities ordered that free-range chickens would have to be kept indoors. EU officials chose not to impose a similar policy on member countries.

Chinese government officials have said more than 1,000 migratory birds have been found dead during 2005.

In late September 2005, the UN health representative responsible for coordinating a response to an outbreak, David Nabarro, stated that a flu pandemic could happen at any time, and kill from five to 150 million people. He further stated that as the virus had spread to migratory birds, an outbreak could start in Africa or the Middle East, rather than southeast Asia as has been widely assumed. At the same time, agricultural ministers of Association of South East Asian Nations announced a three-year plan to counter the spread of the disease.

In early October 2005, Romanian officials quarantined Ceamurlia de Jos, a Danube delta village of about 1,200 people, after three dead ducks there tested positive. However, there have been no immediate reports of sickness in the village. The Agriculture Minister said the virus found in the farm-raised ducks came from migrating birds from Russia. Pending scientific clarification, this is the first time the virus had been detected in Europe. Six villages have been put under quarantine following the deaths of domestic birds and over 6000 birds have been killed.

On 13 October 2005 the EU Health Commissioner Markos Kyprianou confirmed that tests on the dead turkeys found on farms in Kiziksa, Turkey, showed that they had died from the H5N1 strain. Even before the test results were available, some 5,000 birds and poultry have been culled in the area. It is believed that the disease had spread from migratory birds that land at the Manyas bird sanctuary (a few miles from the infected farm) on their way to Africa.

On 14 October 2005, European health officials confirmed what many had long feared -- the arrival of the H5N1 strain on Europe's doorstep. The European Commission said the avian influenza outbreak in Turkey was indeed H5N1, and advised Europe to prepare for a pandemic. It has also been reported in Romania.

On 15 October 2005, the British Veterinary Laboratory in Weybridge confirmed that the virus detected in Ciamurlia, Romania is H5N1.

On 17 October 2005, a avian influenza outbreak occurred in Chios, Greece. The mayor of Chios said a farmer on Oinousses who raised turkeys and chickens noted the previous week that some of his birds had died. Two state veterinarians were sent in to look at nine turkeys. They also took blood samples from some chickens. The mayor said a state lab in Athens confirmed that one of the nine samples proved positive. Authorities have yet to announce what measures they will be taking. The farmer was taken to a hospital for observation.

On 19 October 2005, China announced a fresh outbreak of avian influenza, saying 2,600 birds have died from the disease in Inner Mongolia. The deaths, at a farm near the region's capital of Hohhot, were due to the H5N1 strain, the Xinhua news agency said.

On 21 October/22 October 2005, the British Government announced that a parrot from South America had died in quarantine from H5N1 . Because the parrot died in quarantine, the United Kingdom is still considered free of avian flu. The staff that had been in contact with the parrots were immediately given anti-viral drugs.

On 26 October 2005, Croatia announced H5N1 strain was found in dead swans .

On 31 October 2005, Russia confirmed previously suspected H5N1 avian influenza in ten rural communities across Russia. The confirmed outbreak sites are in the central areas of Tula and Tambov, as well as in the Urals province of Chelyabinsk and in Omsk and Altai, in Siberia.

On 31 October 2005, Canada has discovered a strain of H5 avian flu in wild birds and is now checking whether it is the same H5N1 killer strain which has spread to Europe.

On 11 November 2005, Kuwait has reported positive testing of two birds, one infected with H5N1, and the other with the H5N2 virus, making them the first cases of infection in the Middle East. A flamingo holding the H5N1 virus was found dead by the sea, as the scource reports, it was killed by authorities and did not die from the virus, however, it does not report why it was killed. The second bird, a falcon, was found at the Kuwait airport, holding the H5N2 virus.

On 19 November 2005, Wild birds in Manitoba, Canada have tested positive for a low-pathogenic subtype of the H5N1 avian flu virus.

On Sunday November 20, CTV News reported H5N1 strain was found in a farm in the Fraser Valley area of British Columbia, Canada. The Canadian Food Inspection Agency has ordered a precautionary cull of 65,000 birds.

Pig cases

In February 2004, avian influenza virus was detected in pigs in Vietnam, increasing fears of the emergence of new variant strains. In May 2005, the occurrence of Avian influenza in pigs in Indonesia was reported ("swine flu"). Along with the continuing pattern of virus circulation in poultry, the occurrence in swine raises the level of concern about the possible evolution of the virus into a strain capable of causing a global human influenza pandemic. Health experts say pigs can carry human influenza viruses, which can combine (i.e. exchange homologous genome sub-units by genetic reassortment.) with the avian virus, swap genes and mutate into a form which can pass easily among humans.

Tiger and leopard cases

Variants have been found in leopards and tigers in Thailand, with high lethality.

Human cases

Human Cases and Deaths of H5N1
Human Cases and Deaths of H5N1

Worst case scenario

The worst case scenario for a H5N1 pandemic is somewhere around 150,000,000 human deaths directly due to H5N1 infection (or two to three percent of the world's human population). No one knows what the chances are for this worst case scenario.

"Influenza viruses keep changing. They mutate. And they exchange genetic material with other flu viruses, a process called reassortment. All that's needed is a mutation or reassortment that produces a new variant of H5N1 one that's as deadly as the current strain but as easily transmitted from human to human as lots of other flu strains. Most virologists believe something like this will happen sooner or later, and many believe it will happen soon. When it does, H5N1 will inevitably spread throughout the world. Worldwide mortality estimates range all the way from 2-7.4 million deaths (the "conservatively low" pandemic influenza calculation of a flu modeling expert at the U.S. Centers for Disease Control and Prevention) to 1 billion deaths (the avian influenza pandemic prediction of one Russian virologist). The estimates of most H5N1 experts range less widely but still widely. In an H5N1 pandemic, the experts guess that somewhere between a quarter of us and half of us would get sick, and somewhere between one percent and five percent of those who got sick would die the young and frail as well as the old and frail. If it's a quarter and one percent, that's 16 million dead; if it's a half and five percent, it's 160 million dead. Either way it's a big number." Pandemic Influenza Risk

Sloppy science blamed for US bird flu scare - Western Producer (subscription)
21 Aug 2014 at 1:39pm
Sloppy science blamed for US bird flu scare - Western Producer (subscription)
21 Aug 2014 at 1:39pm
Dead birds spark lake concern - St Helens Star
21 Aug 2014 at 1:06am
Dead birds spark lake concern - St Helens Star
21 Aug 2014 at 1:06am
Hatoful Boyfriend gets bird flu, delayed to September - IncGamers.com
19 Aug 2014 at 4:34pm
Hatoful Boyfriend gets bird flu, delayed to September - IncGamers.com
19 Aug 2014 at 4:34pm
Human Error at CDC Almost Unleashes Bird Flu and Smallpox in the US - Chinatopix
19 Aug 2014 at 7:34am
Human Error at CDC Almost Unleashes Bird Flu and Smallpox in the US - Chinatopix
19 Aug 2014 at 7:34am
Procedures to Prevent New Avian Flu Strain A/H5N6 - ThePoultrySite.com
19 Aug 2014 at 3:15am
Procedures to Prevent New Avian Flu Strain A/H5N6 - ThePoultrySite.com
19 Aug 2014 at 3:15am
CDC Accidentally Shipped A Deadly Avian Flu Virus To Department of Agricultur...
18 Aug 2014 at 10:00am
CDC Accidentally Shipped A Deadly Avian Flu Virus To Department of Agricultur...
18 Aug 2014 at 10:00am
CDC Scientist Kept Flu Blunder Quiet - News Channel Daily
18 Aug 2014 at 9:23am
CDC Scientist Kept Flu Blunder Quiet - News Channel Daily
18 Aug 2014 at 9:23am
CDC Scientist Mishandled Bird Flu Virus Earlier This Year; Risked Cross ... -...
18 Aug 2014 at 8:46am
CDC Scientist Mishandled Bird Flu Virus Earlier This Year; Risked Cross ... -...
18 Aug 2014 at 8:46am
CDC scientist kept quiet about bird flu blunder - Mohave Valley News
18 Aug 2014 at 1:41am
CDC scientist kept quiet about bird flu blunder - Mohave Valley News
18 Aug 2014 at 1:41am
Suspected bird flu hits ducks in Indonesian province - The Nation
18 Aug 2014 at 12:41am
Suspected bird flu hits ducks in Indonesian province - The Nation
18 Aug 2014 at 12:41am
How flu sample was tainted with deadly strain - Independent Online
18 Aug 2014 at 12:13am
How flu sample was tainted with deadly strain - Independent Online
18 Aug 2014 at 12:13am
Efforts stepped up to curb bird flu - SGGP
18 Aug 2014 at 12:01am
Efforts stepped up to curb bird flu - SGGP
18 Aug 2014 at 12:01am
Scientist kept quiet about flu blunder - MorungExpress
17 Aug 2014 at 10:26am
Scientist kept quiet about flu blunder - MorungExpress
17 Aug 2014 at 10:26am
Lab Scientist Kept Quiet About Bird Flu Blunder, CDC Says - Huffington Post
16 Aug 2014 at 8:41am
Lab Scientist Kept Quiet About Bird Flu Blunder, CDC Says - Huffington Post
16 Aug 2014 at 8:41am
Vietnam alerts for bird flu outbreaks - SGGP
16 Aug 2014 at 2:03am
Vietnam alerts for bird flu outbreaks - SGGP
16 Aug 2014 at 2:03am
A Hedge Against Flu or a Danger to Us All? - Emergency Management
15 Aug 2014 at 9:41am
A Hedge Against Flu or a Danger to Us All? - Emergency Management
15 Aug 2014 at 9:41am
Shortcuts Led to Bird Flu Virus Mistake: CDC - HealthDay
15 Aug 2014 at 5:59am
Shortcuts Led to Bird Flu Virus Mistake: CDC - HealthDay
15 Aug 2014 at 5:59am
Vietnam detects first H5N6 bird flu in poultries - Thanh Nien Daily
15 Aug 2014 at 3:35am
Vietnam detects first H5N6 bird flu in poultries - Thanh Nien Daily
15 Aug 2014 at 3:35am
South Korea to tackle AI through wild bird monitoring - WorldPoultry.net
15 Aug 2014 at 2:27am
South Korea to tackle AI through wild bird monitoring - WorldPoultry.net
15 Aug 2014 at 2:27am
S. Korea to launch year-round watch against bird flu - Yonhap News
13 Aug 2014 at 6:14pm
S. Korea to launch year-round watch against bird flu - Yonhap News
13 Aug 2014 at 6:14pm