Poultry markets on close watch after virus detected in bird samples
A previously unknown strain of avian flu has been discovered in China, and the agriculture commission has ordered stricter monitoring of poultry trading areas after the virus was detected in samples from at least three poultry markets.
According to Xinhua, 14 people have so far been infected with the new strain of H7N9 avian flu. Six have died and several others are listed as being in critical condition at a hospital in Nanjing. One of the people diagnosed with the new strain of avian flu was a 38-year-old cook, another was a poultry butcher, and one was a poultry transporter.
So far it seems like people are contracting the disease through contact with infected birds, and no cases of the virus are reported to have been transmitted from one human to another.
Shanghaiist reports that on Thursday the ministry of agriculture shut down a poultry market in Shanghai after pigeon samples there tested positive avian flu. Scientists said that after gene sequencing the virus strain at the poultry market was discovered to match the virus in the infected patients.
The market was ordered to be immediately shut down and all the poultry slaughtered. Two other markets also had their trade suspended and were ordered to be disinfected after the virus was found at them.
The health and planning commission says vaccines for the new strain might be six to eight months away.
If a new strain of bird flu was not enough, on April 3 a man in Hunan died of what was initially reported to be the new bird flu, but he was actually infected with a new strain of the H1N1 swine flu.
France to kill 600,000 poultry in effort to contain bird flu
Seven workers at a poultry farm in southern Russia were the first humans to catch the H5N8 strain of avian influenza in humans.
Russia told the World Health Organization that the virus isn’t yet spreading between people, Anna Popova, the country’s public health chief, said Saturday, Bloomberg reported. All of the farmworkers had asymptomatic cases and recovered, she said.
The strain was first reported in November, found in 15 Russian regions among both poultry and wild birds. It was not considered dangerous to humans at first.
“It is not transmitted from person to person,” Popova said. “But only time will tell how soon future mutations will allow it to overcome this barrier.” The world has a chance to prepare for possible mutations and to respond in a timely way to develop tests and vaccines for the strain, she said.
Siberia’s Vector Institute said on Saturday it would start developing human tests and a vaccine against H5N8, RIA news agency reported.
Chickens await vaccination against bird flu at the settlement Peredovoi 62 miles from the Russia’s southern city of Stavropol on March 11, 2006. REUTERS/Eduard Korniyenko/File Photo
WHO acknowledged that it received the information from Russia. “We are in discussion with national authorities to gather more information and assess the public health impact of this event,” the organization said in an email to Reuters.
H5N8 has also been found in France, where hundreds of thousands of birds were slaughtered last month to prevent the spread. It was also behind the worst bird flu outbreak in Japan on record in late 2020, and has been found in China, the Middle East and North Africa in recent months, but so far only in poultry.
A green-winged teal shot by a hunter in northern Washington state has tested positive for a strain H5N1 bird flu — but it's only a distant relative of the virus that’s infected nearly 700 people globally and killed 400 of them.
It’s the first case of highly pathogenic H5N1 avian influenza ever seen in the U.S. The good news is that the strain is genetically different from the strain that’s circulated in China, across Asia and most recently in Egypt. It doesn’t appear to have infected any people or even domestic poultry.
But it shows that wild migrating birds can carry dangerous viruses to the U.S., says Hon Ip, an expert on wildlife pathogens at the U.S. Geological Survey in Madison, Wisconsin.
"Unlike the Asian H5N1 strain that has been found in Asia, Europe, and Africa, this Washington state strain has only been found in wild waterfowl and has not been associated with human illness, nor has this new Washington state strain been found in domestic poultry," USGS said in a statement.
The U.S. Department of Agriculture will need to keep a close eye out for other birds with H5N1, Ip said.
“At the moment we do not know of a single human case with our H5.”
“USDA and the Department of the Interior are going to have to spend time to understand the implication of this introduction,” Ip told NBC News. “At the moment, we do not know of a single human case with our H5.”
Flu is a mutation-prone virus and there are hundreds of strains. Even with precise-sounding names such as H5N1, there can be a large degree of genetic variation. Scientists are watching for mutations and other genetic changes that can make a virus strain more likely to infect people and poultry.
The H5N1 that most people are worried about has killed or forced the destruction of hundreds of millions of chickens around the world. It occasionally infects people and the fear is it will mutate into a form that makes it pass easily from person to person. That would spark a pandemic that could kill millions.
H7N9 Bird Flu: 2 New Cases, Including One Death, Discovered In China
BEIJING/LONDON, April 3 (Reuters) - China has found two more cases of a new strain of bird flu and one of the victims has died, state media said on Wednesday, bringing to nine the number of confirmed human infections from the previously unknown flu type.
A 38-year-old cook fell ill early last month while working in the province of Jiangsu, where five of the other cases were found. He died in hospital in Hangzhou city on March 27, the Xinhua news agency reported. Samples tested positive on Wednesday for the new bird flu strain, H7N9.
The second patient, also in Hangzhou, is a 67-year-old who is having treatment. Xinhua said no connection between the two cases had been discovered, and no one in close contact with either patient had developed any flu-like symptoms.
The World Health Organization said it was "following the event closely" and was in contact with Chinese authorities, which it said were actively investigating the cases amid heightened disease surveillance.
Flu experts across the world are studying samples isolated from the patients to assess H7N9'S human pandemic potential.
Other strains of bird flu, such as H5N1, have been circulating for many years and can be transmitted from bird to bird, and bird to human, but not generally from human to human.
So far, this lack of human-to-human transmission also appears to be a feature of the H7N9 strain.
Of the seven other cases of the new strain, two have died, both in the business hub of Shanghai. The other five are in a critical condition in hospital in Nanjing. Shanghai, Nanjing and Hangzhou are all close to each other in eastern China.
China's Agriculture Ministry said it had yet to find any animals infected with H7N9, though added it was possible it had been brought to China by migratory birds.
The WHO says so far it has seen no evidence of human-to-human transmission, but there are questions about the source of the infection and about how it may be being transmitted to people.
"We still don't know the mode of transmission or host (of the virus)," said WHO spokesman Gregory Hartl. "Those are the two most important pieces of information we would need. In order to control it, we need to know where it is coming from."
The WHO said in a statement it was also focusing its efforts on encouraging collaboration between researchers to ensure information and materials are available for scientists wanting to develop diagnostic tests, drugs and vaccines.
No vaccine is currently available for H7N9 flu, but preliminary test results provided by the WHO Collaborating Centre in China suggest it is susceptible to the antiviral drugs Tamiflu, sold by the Swiss drugmaker Roche, and Relenza, sold by Britain's GlaxoSmithKline.
Chinese authorities dismissed speculation on some websites that the H7N9 outbreak may be related to more than 16,000 pig carcasses found dumped in rivers around Shanghai.
Yin Ou, deputy director of the Shanghai Municipal Agricultural Committee, told reporters on Tuesday that the city had tested 34 dead pigs found in the city's Huangpu River for the H7N9 virus, but the tests had all come back negative.
China has a chequered record when it comes to tackling disease outbreaks, which some officials have previously sought to cover up. However, since the H7N9 cases have been identified, China has stepped up its alert level and said it is being transparent in dealing with them.
In 2003, authorities initially tried to cover up an epidemic of Severe Acute Respiratory Syndrome, which emerged in China and killed about a 10th of the 8,000 people it infected worldwide.
Risk to Humans Seen in New Bird Flu Strain
BEIJING—Scientists warned that a strain of avian flu has mutated and can now infect humans, requiring close scrutiny, while authorities were cautiously watching another strain making its way through China.
The Lancet medical journal said in a study published Wednesday that a strain of the H10N8 avian flu mutated and can now be carried by humans. The study followed findings by Chinese researchers that the H10N8 flu had been found in two people in recent months. The first, a 73-year-old woman in the city of Nanchang in Jiangxi province, died Dec. 6.
The Lancet study said the new strain had genetic similarities to two other types of avian flu—H5N1 and H7N9—that jumped from birds to people and have led to deaths in humans. Its authors also said H10N8 hasn't produced major reported outbreaks of disease in poultry, meaning it could quietly spread in flocks.
The findings showed that the disease hadn't been transmitted from person to person, which would make it more dangerous. Still, they warned that the new strain warranted caution. "The pandemic potential of this novel virus should not be underestimated," the authors wrote.
Chinese and international health officials have closely watched the spread of the H7N9 virus during the current winter-driven flu season. H7N9 has killed 25 people in China since January, while more than 113 people have been infected, the state-run Xinhua news agency said Monday. On Wednesday, Xinhua said authorities had reported 11 more people infected, with eight in critical condition.
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(CNN) — A new variation of bird flu that the WHO says has caused at least 11 deaths in China has genetic characteristics that make it well-adapted to infect people.
In a report published late Thursday in the New England Journal of Medicine, samples from three patients — all of whom died — had mutations that have previously been shown to increase transmissibility, and to help the virus grow in a mammal’s respiratory tract.
The analysis comes amid a modest but steady stream of human cases since the end of March. On Friday, China reported five new laboratory-confirmed cases of the H7N9 flu strain, bringing the total to 43. The strain is normally found in birds, and until last month was never known to infect people.
“The H7N9 situation is evolving very quickly,” said Nancy Cox, director of the Influenza Division at the U.S. Centers for Disease Control and Prevention. “One thing of concern is the pace at which we are seeing the identification of cases.”
On a more reassuring note, investigators have found no evidence that the virus has passed directly from person to person. More than a thousand “close contacts” of the patients are being monitored by Chinese health officials, according to the World Health Organization.
One concerning mutation, known as “Substitution Q226L,” was found in two of the first three victims. Past experiments have shown it to make viruses — including the H5N1 bird flu virus — more likely to infect ferrets, which are commonly used in flu research. The same mutation was also found in the viruses that caused the 1957 and 1968 flu pandemics.
A second mutation, known as “PB2 E627K,” was found in all three virus samples.
According to Dr. Ron Fouchier, a Dutch virologist, this mutation allows the virus to reproduce at much lower temperatures than a standard avian influenza virus. The change lets it grow in a human respiratory tract, which is cooler than the virus’ natural home: a bird’s gastrointestinal tract.
In mice, Fouchier said, the mutation makes the infection as much as 1,000 times more virulent.
A number of other mutations were found as well, including changes that are characteristic of viruses found in mammals.
“Known normal bird viruses have to adapt substantially to infect people, but not these,” said Fouchier, who said the changes are enough that he would no longer call the H7N9 strain “bird flu.”
The first three patients to be identified are an 87-year-old man and a 27-year-old man from Shanghai, and a 35-year-old housewife from Anhui.
The woman had visited a chicken market about a week before falling ill. The younger man was a butcher who worked in a market where live birds were sold, although he did not butcher any birds. The 87-year-old had no known exposure to live birds.
All three died after suffering severe respiratory symptoms, including acute respiratory distress syndrome and eventually septic shock and multiple organ failure.
In a commentary that ran with the article, Cox and Dr. Tim Uyeki, a physician with the CDC, noted that patients were not given antiviral medication until their illness became severe.
Oseltamivir (Tamiflu) or zanamivir (Relenza) should be administered as soon as possible to patients with a suspected or confirmed H7N9 infection, the two wrote.
Cox said it remains unclear whether the severe illnesses are typical of H7N9 infection or simply the tip of a large iceberg in which a large number of mild cases are going unnoticed.
“As surveillance has expanded, we’re also seeing individuals with milder cases,” said Cox. “We’re still seeing very severe disease in some cases, but overall I think it’s somewhat reassuring.”
The CDC is in the final steps of refining a diagnostic test to identify H7N9 in patients, and Cox said it should be available for distribution in a matter of days. A widely available diagnostic test would allow faster identification of patients who actually have the infection, and would also help disease detectives zero in on how people are being exposed.
Work has begun on a vaccine, although Cox and others said that even if it is eventually needed, a vaccine likely won’t be available for several months.
While the overall picture is concerning, flu experts urged calm.
“I wouldn’t say a pandemic is more likely than it was a year ago,” Fouchier said. “The only thing we can do as virologists right now is to point out the interesting characteristics of the virus, try to get to the bottom of this story and try to stop further infections.”
U.S. public health officials watching bird flu outbreak in China
U.S. health officials are developing laboratory strains of China's new bird flu so they can make vaccines quickly if necessary.
The move is in response to a new bird flu that has emerged in China in the past two months. So far, it is confined to that nation.
Bird flu has killed six of the 21 people who've gotten it, a mortality rate that keeps public health officials up at night. The strain, named H7N9, appears to be transmitted from poultry.
This week,Chinese officials began slaughtering more than 20,000 birds in a Shanghai poultry market to help stop the spread of the strain, which has been found in four provinces along China's eastern seaboard.
Chinese health officials are monitoring more than 530 people who had been in close contact with confirmed cases, the World Health Organization reported.
The United States has not issued any travel advisories for China but for a decade has advised Americans traveling to China to avoid contact with birds and other animals.
The Centers for Disease Control and Prevention is on the case, said CDC director Thomas Frieden.
"We work to have the public's back," Frieden said. "It's our job to be concerned and to move quickly whenever there's a potential problem."
But the public doesn't need to worry, he said. "There's no evidence that the virus is being transmitted between people or that it's present in the United States."
Public health officials are engaged in aggressive surveillance, said William Schaffner, an influenza expert who chairs Vanderbilt University's department of preventive medicine in Nashville. Any out-of-the ordinary pneumonia cases in the United States are being looked at carefully and specimens sent to ultra-fast specialty labs, and the results are communicated quickly to federal health officials, Schaffner said.
The good news is that compared with the severe acute respiratory syndrome (SARS) outbreak in 2003, China has made huge changes to how it responds to this kind of outbreak, Schaffner said.
"Ten years ago, China was very secretive and the world's health community was frustrated," he said. "This time around, China is being very open and aggressive in dealing with the outbreak."
The H7N9 bird flu in China is of concern because it's a new strain that hasn't been seen in humans before, said Joseph Bresee, chief of the CDC's epidemiology and prevention branch, influenza division. However, so far it seems the only way to get it is to be in close contact with sick poultry.
Chinese health officials quickly developed a test for exposure to the virus, then took blood samples from more than 100 people who'd had close physical contact with the first three people who got the flu strain. None of them had any evidence of immunological response, meaning their bodies hadn't been exposed to it.
"With influenza you'd expect at least 20% to 30% of family members to develop illness," said Frieden. "So that's good news."
Bird flu strains regularly emerge in southeast Asia, where there are large poultry flocks. Every few years, one appears that humans can get, but usually only by coming into contact with sick birds. Health officials worry when a strain emerges that can pass easily from human to human.
That hasn't happened in this case, health officials emphasize.
At least, it hasn't happened yet, Schaffner said. Flu viruses are notoriously changeable virologists talk about their "constant genetic turbulence." That's why "we have to watch this outbreak like a hawk, because if it does mutate, we could have a worldwide flu pandemic on our hands," he said.
To be on the safe side, health officials and vaccine manufactures are creating the strains now, Frieden said. "It would only be produced if there was evidence of widespread human-to-human transmission," he said.
The U.S. effort began "within a matter of days" of the first word of the new variant, Schaffner said.
While the news out of China might sound scary, the global response is immensely reassuring, he said.
"The average person should say 'Wow. This is an international, integrated public health prevention structure that's really working!' Schaffner said. "This is exactly how the international community ought to work."
Third death in China from new bird flu strain
A vendor waits for customers near chicken cages at a market in Fuyang city, in central China's Anhui province, Sunday, March 31, 2013. (AP/AP)
BEIJING — Chinese authorities tried to calm spreading health concerns Wednesday after a third person was reported to have died from a new type of bird flu.
The emergence in China of the H7N9 strain of avian flu — a total of nine cases have been reported since it was revealed last weekend — are troubling because the strain has not previously been found in humans.
Even as two new cases were announced Wednesday, China’s state media sought to reassure the public that the chances of contracting H7N9 remain low. They also said that testing kits developed for the strain have been distributed to the national flu-monitoring network. Nothing so far, authorities stressed, suggests that the strain can be transmitted from one human to another.
The World Health Organization also urged calm this week but noted the importance of determining how the virus came to infect humans and whether it might spread. Just one patient so far appeared to have had direct contact with poultry. Dozens of people who came into contact with each patient are being monitored, authorities said.
A different strain of bird flu, H5N1, that emerged in 2003 has killed more than 370 people, according to the WHO.
Local media on Wednesday described the latest fatality as a 38-year-old chef in the eastern province of Zhejiang. A second patient from the same area was described as a 67-year-old retiree who was being treated in a hospital. Authorities revealed over the weekend that two other men had died in Shanghai.
Shanghai officials appeared particularly eager to dispel rumors that the new avian flu strain was related to the recent scandal triggered by the discovery of more than 15,000 dead pigs in Shanghai-area rivers. Public statements released Wednesday were aimed at assuring citizens that poultry and pork supplies in the city remain safe to eat.
The Shanghai Animal Disease Prevention and Control Center tested 34 samples from pig carcases and reported finding no traces of bird flu, state media reported. Many city residents, however, remain skeptical.
This week, Vietnam enacted a ban on all poultry products from China, stepping up border controls, while Taiwan put officials on alert and set up a monitoring group as a precaution against an epidemic-level outbreak.
Some experts have deemed China a higher risk for bird flu given the sheer size of its poultry industry and its use of production methods that put farmers in closer proximity to their chickens.
In their media and public-health response, Chinese authorities have been haunted by the specter of past medical crises, most notably the SARS outbreak of 2002 and 2003, when official censorship and tight control of information worsened matters. But Zhong Nanshan, director of the Chinese Medical Association, told Chinese media it is considered very unlikely that this bird flu strain will turn into a problem on the scale of SARS.
New bird flu strain linked to death of Chinese woman
Chinese authorities have said a 73-year-old woman has died after being infected with a bird flu strain not previously found in people, a development that the World Health Organisation called "worrisome".
China's Centre for Disease Control and Prevention said the woman in Nanchang had been infected with the H10N8 bird flu virus, the Jiangxi province health department said on its website.
This is the second new bird flu strain to emerge in humans this year in China. In late March the H7N9 bird flu virus broke out, infecting 140 people and killing 45, almost all of them on the mainland. The outbreak was controlled after the country closed many of its live animal markets. Scientists assumed the virus was infecting people through exposure to live birds.
Timothy O'Leary, spokesman for the WHO's regional office in Manila, said officials were working closely with Chinese authorities to better understand the new virus. He said it would not be surprising if another human case was detected.
"It's worrisome any time a disease jumps the species barrier from animals to humans. That said, the case is under investigation [by Chinese authorities] and there's no evidence of human-to-human transmission yet," O'Leary said.
The Jiangxi health department said the woman had severe pneumonia before dying on 6 December in a hospital in Nanchang. She had suffered high blood pressure, heart disease and other underlying health problems that lowered her immunity, the health department said. Her medical history showed that she had been in contact with live poultry.
The health department said no "abnormalities" had been found in people who had close contact with her. It did not say whether they had been tested or quarantined, though China has in previous outbreaks taken those measures.
Experts are cautious when it comes to bird flu viruses infecting humans. They have been closely watching the H5N1 bird flu virus, which has killed 384 people worldwide since 2003. The virus remains hard to catch with most human infections linked to contact with infected poultry, but scientists fear it could mutate and spread rapidly among people, potentially sparking a pandemic.
New bird flu poses "serious threat", scientists say
LONDON (Reuters) - A new strain of bird flu that is causing a deadly outbreak among people in China is a threat to world health and should be taken seriously, scientists said on Wednesday.
The H7N9 strain has killed 24 people and infected more than 125, according to the Geneva-based World Health Organization (WHO), which has described it as “one of the most lethal” flu viruses.
The high mortality rate, together with relatively large numbers of cases in a short period and the possibility it might acquire the ability to transmit between people, make H7N9 a pandemic risk, experts said.
“The WHO considers this a serious threat,” said John McCauley, director of the WHO Collaborating Centre for Influenza at Britain’s National Institute for Medical Research.
Speaking at a briefing in London, experts in virology said initial studies suggest the virus has several worrisome characteristics, including two genetic mutations that make it more likely to eventually spread from person to person.
“The longer the virus is unchecked in circulation, the higher the probability that this virus will start transmitting from person to person,” Colin Butte, an expert in avian viruses at Britain’s Pirbright Institute, said.
Of the some 125 people infected with H7N9 so far, around 20 percent have died, approximately 20 percent have recovered and the remainder are still sick. The infection can lead to severe pneumonia, blood poisoning and organ failure.
“This is a very, very serious disease in those who have been infected. So if this were to become more widespread it would be an extraordinarily devastating outbreak,” Peter Openshaw, director of the center for respiratory infection at Imperial College London, told the briefing.
Scientists who have analyzed genetic sequence data from samples from three H7N9 victims say the strain is a so-called “triple reassortant” virus with a mixture of genes from three other flu strains found in birds in Asia.
Recent pandemic viruses, including the H1N1 “swine flu” of 2009/2010, have been mixtures of mammal and bird flu - hybrids that are likely to be milder because mammalian flu tends to make people less severely ill than bird flu.
Pure bird-flu strains, such as the new H7N9 strain and the H5N1 flu, which has killed about 371 of 622 the people it has infected since 2003, are generally more deadly for people.
Human cases of the H7N9 flu have been found in several new parts of China in recent days and have now been recorded in all of its provinces.
Last week a man in Taiwan became the first case of the flu outside mainland China, though he was infected while travelling there.
The H7N9 strain was unknown in humans until it was identified in sick people in China in March.
Scientists say it is jumping from birds - most probably chickens - to people, and there is no evidence yet of the virus passing from person to person.
Jeremy Farrar, a leading expert on infectious diseases and director of Oxford University’s research unit in Vietnam, said the age range of those infected so far stretched from toddlers to people in their late 80s - a range that appeared to confirm the virus is completely new to the human population.
“That suggests there truly is no immunity across all ages, and that as humans we have not seen this virus before,” he said.
“The response has to be calm and measured, but it cannot be taken lightly,” he said.