BIRD FLU IN CHINA
As of March 2008, there were 20 confirmed bird flu deaths and 379 people had contacted bird flu in China. At that time and 239 had died of the disease worldwide, with most of the deaths in Southeast Asia.
China has been blamed for being the source of bird flu, a charge that officials in China have vehemently denied. A study published in November 2006, reported that the strain of bird flu found in most of the poultry outbreaks and some human cases in southern China---H5N1 Fujian-like---was also the primary strain found in Hong Kong, Laos, Thailand and Malaysia.
Genetic analysis of the various H5N1 strains by a team at the University of California in Irvine, published in the Proceedings for the National Academy of Sciences in March 2007, determined the source of the H5N1 Fujian-like virus was Guangdong Province in southern China. Genetic analysis of the H5N1 strains that showed up in Vietnam, Thailand and Malaysia in 2002 and 2003 closely resemble a strain from poultry markets in China’s Yunnan Province
China has repeatedly asserted that was not the source of bird flu and directly asserted the claim made by the University of California in Irvine team was “the wrong conclusion to the evidence and lacked credibility.”
Outbreaks of Bird Flu Among Birds in 2004 in China
In early 2004, China reported 49 confirmed cases of H5N1 avian influenza (bird flu) during an Asia-wide epidemic of the disease. The first cases---among ducks in Guangxi Province---were reported in late January. The government moved aggressively to combat the disease---culling 9 million chickens and quarantining farming areas---and declared it “stamped out” by March. No cases of human transmission were reported.
The government was eager not to repeat the mistakes made with SARS. For the most part it seemed eager and willing to cooperate with the WHO and other international organizations. A network of 300 stations was set up to monitor the disease. Road blocks were set up around infected areas and teams were sent to infected villages to kill all the poultry they could find.
In some cases teams arrived in villages in the middle of the night rounded up all the chickens, ducks and geese in the village and suffocated them on plastic bags and then carried the dead birds off. To ensure that all the domesticated birds in the village had been killed, team members who stayed in tents stuck around for several days to make sure no stragglers survived. Farmers who owned the birds were compensated by the government for their losses.
In August 2004, Chinese scientists at a laboratory in Harbin said they discovered a H5N1 in pigs. It was not clear whether the pigs were infected with the disease or had picked up the disease in their snouts without becoming infected. See Vietnam.
In August 2004, an outbreak of bird flu was reported in Anhui Province after dead chickens, ducks and geese discovered at farms there were found to be carrying the bird flu virus. The government took action to prevent the disease from infecting people. There were reports that a girl died of flulike symptoms after eating sick chickens.
Outbreaks of Bird Flu Among Birds in 2005 and 2006 in China
In June 2005, wild birds with bird flu were found dead at Lake Qinghai Nature Reserve in Qinghai Province, an important transit area for 189 species of migratory bird. Thousands of wild birds---including bar-headed geese, cormorant and black-headed gulls---came down the with the disease. It was the largest known outbreak among wild birds Some thought migratory birds were the source. Others think the disease was brought to region from live poultry based on the fact that such a large number of birds would not have been able to fly to the remote region if they were sick. People were barred from entering the region Three million domesticated birds in the area were vaccinated.
In July 2005, there were outbreaks of bird flu in Xinjiang, with one case near Kazakhstan. Most of the infected birds were domesticated geese and ducks. Migratory birds may been involved in spreading the disease. A third of the bird flu cases in 2005 were in Xinjiang. In August 2005, 2,608 birds at a chicken farm near Lhasa in Tibet were culled to contain an outbreak of bird flu there after 113 chickens died from the disease.
There were 29 outbreaks of bird flu in areas throughout China between October 2005 and January 2006, with the first outbreaks in Anhui Province. The first poultry cases were limited to chickens but later ducks and geese also became infected. The outbreaks are thought to have been spread by migrating wild geese and struck places as far apart as Hunan, Inner Mongolian and Xinjiang.
Liaoning Province was particularly hard hit in part because it lies on major routes for migratory birds traveling to and from Siberia. One farmer in the village of Taian told the Times of London, “I was very frightened. Some of my chickens were sick when I fed them in the morning and I came back after lunch they were dead. I knew it must be bird flu because trucks go down the streets every day broadcasting warnings.” Within hours his 3,800 birds had been incinerated. A total of 160,000 birds were destroyed in the farmer’s village and 12 million were killed in Liaoning. Another 320 million were vaccinated. Farmers were happy to get $1.20 per chicken in compensation even though the could have gotten twice as much had they sold their birds in market.
During the outbreak the government took strict anti-flu measures. Millions of chickens, ducks and other poultry were killed; poultry markets were closed down; and shipments of poultry were inspected nationwide. Roadblocks were set up outside infected areas and vehicles were required to drive over corn starch sprayed with disinfectant. In May 2006, bird flu was discovered in a dead goose Qinghai Province in northwestern China. In July 2006, bird flu was found in the northwestern region of Ningxia.
As of March 2008 there were five outbreaks of bird flu in China in 2008. The fifth out outbreak occurred in Guangzhou, where chicken in a poultry market were found to have the H5N1 virus. There were two outbreaks of bird flu in Tibet in the winter of 2008. One was in village outside of Lhasa.
Early Human Bird Flu Victims in China
The first human victim of bird flu in China was a 24-year-old soldier who died in 2003. The man was thought to have had SARS but tests conducted later confirmed he had bird flu. The case was not revealed until 2006. It was first reported in a letter by Chinese researcher to the New England Medical Journal and was confirmed by China’s health ministry in August 2006.
In November 2005, three women---two farmers in the central province of Anhui and a farmer in the northern province of Liaoning---and 12-year-old girl in Hunan Province died from the bird flu. The girl became weak and pale after eating a dead duck and died six days later of a lung infection. The duck also sickened members of her family.
Other bird flu deaths included a 10-year-old girl in Guanxi and a 35-year-old man from Jiangxi in December 2005; and a 31-year-old woman and a 29-year-old woman in Sichuan Province in January 2006,
In February 2006, a 20-year-old female farmer in Suining in southern Hunan Province became the 8th person to die from bird flu in China. Several other people in the areas became ill with the disease, Some of the victims said they had no contact with poultry They are thought to have come in contact with the virus in their surroundings.
In March 2006, a 32-year-old man from Guangzhou in Guangdong Province and a 9-year-old girl from coastal province of Zhejiang died from bird flu. The man did a survey at local markets and spent a long time near a place where chickens were slaughtered. In April a 21-year-old migrant died of bird flu and an 8-year-old girl in southwest Sichuan came down with it after she came in contact with poultry sickened by the disease.
In June 2006, a truck drive from Shenzhen was diagnosed with bird flu. he was the 19th reported to have contacted the disease. In August 2006, a farmer in western China became the 14th person to die from bird flu in China.
Later Bird Flu Victims in China
In March 2007, a 16-year-old boy from Bengui in Anhui Province died if bird flu. he was the third victim in China in 2007. A 44-year-old farmer in Fujian Province and 37-year-old farmer in Anhui Province also came down with the disease. There was also an outbreak in Tibet.
In June 2007, a 19-year-old Chinese soldier stations din Fujian Province died of bird flu. The government did not release information on where he was stationed or how he might have contacted the disease.
The three deaths in 2008 included a 22-year-old man in central China and a 44-year-old female migrant worker who died in Haifeng County in eastern Guangdong Province in February. The woman had come into contact with poultry.
In February 2009, the first bird flu outbreak among poultry of the year broke out in Xinjiang. More than 13,000 fowl were culled.
In January 2009, three people died of bird flu, including a 27-year-old woman in the city of Jinan in Shandong Province; a 16-year-old male student in Hunan Province; and a 19-marriage woman in Hebei Province. All three of the victims had come in contact with infected poultry. The mother of a two-year-old toddler that came down with disease in Hunan Province died of pneumonia. Before that nearly a year had passed with no report of human cases of bird flu. The deaths brought the brought the bird fu death total in China to 21.
Human-to-Human Transmission of Bird Flu in China
In November and December 2007 there was a case of human-to- human transmission of bird flu in the eastern province of Jiangxi Province in China involving a 52-year-old father and his 24-year-old son. The two were diagnosed with bird flu within a week of each other. Ths son picked up the virus from poultry while the father had no known contact with the virus except from his son. The son died. He was the 17th reported death from the disease in China.The father who was diagnosed at an early stage of the disease, survived.
The strains of H5N1 found in the father and son were almost identical. The father was treated with antivirals and plasm from a woman who had been vaccinated against H5N1 in a clinical trial, which suggests this method or similar methods may be useful in treating the disease,. The Chinese government was unusually forthcoming with data from the cases, which give the international researchers useful information to fight bird flu.
The Jiangxi father and son case was carefully studied by Chinese scientists who published a report in The Lancet. Among their findings, which were encouraging in terms that the virus still lacked a punch to become a pandemic, were: 1) the strain of the virus found in the father and son were similar to the standard strain which showed that little mutation had taken place; 2) the father and son came in close contact with 91 other people who didn’t catch the disease, which suggests it doesn’t pass easily to humans; and 3) the fact that two close relatives caught the disease, raises the possibility they might have a genetic susceptibility to the disease, and if that is case this could lead to better ways of treating the disease and even developing drugs and vaccine to fight it.
There have been a dozen cases of possible human-to-human bird flu transmissions. In every case the transmission occurred between close blood relatives who had been in close contact with the virus, and the disease did not spread to the wide community.
Combating Bird Flu in China
During the outbreaks of bird flu between October 2005 and January 2006 thousands of teams on motorcycles fanned out across China, going from village to village and house to house, vaccinating chickens, geese and ducks for bird flu. Each team handled about 600 birds a day. The goal of the nationwide effort was to innoculate all of China’s 14.2 billion domesticated birds. Nearly a million officials and soldiers were mobilized in Liaoning Province alone. The government is worried about migratory workers from the countryside bringing the disease to the cities.
Typically the team had little training. Often one person held the bird, while another swabbed it and a third person injected the needle. Many workers failed to take even the most basic hygienic measures such as wearing rubber gloves and masks. Sometimes used needles were simply discarded on the ground. There were worries the teams might catch and spread the disease.
Production of bird flu vaccines were stepped up. Nine plants worked around the clock producing 100 million doses a day. The inoculation effort proceeded relatively smoothly and rapidly in poultry farming areas but was slower going in hard-to-reach areas. Many places complained about receiving supplies late or receiving far less vaccinations than they needed.
The pharmaceutical giant Roche and the state-owned Shanghai Pharmaceutical company reached an agreement to make the bird flu drug Tamiflu in China. The Chinese government was criticized all the misuse of amantadine an effective bird flu drug intended for humans. Farmers used the drug on poultry which can make the virus resistant to the drug in birds and then make it useless in human cases.
The WHO complained that China refused hand over samples of the disease collected during the outbreaks in 2005 and 2006. Some speculated that China failed to do this so it could make a vaccine and reap huge profits before foreign competitors could make one. Researchers from Hong Kong complained that Chinese authorities interfered with their studies of the disease.
In 2006, 100 hundred monitoring stations and 1,000 workers were spread along bird migration routes in Jiangsu Province eastern China to monitor if the disease was being spread by migrating birds. An estimated 3 million birds pass through the area being monitored.
The raising of chickens in urban areas was banned in Shandong Province, where a 27-year-old woman died of bird flu in the city of Jinan
Bird Flu in China in 2011
In December 2011, The Independent reported: “A Chinese bus driver died of bird flu today - sparking fears there will be a fresh outbreak of the potentially deadly disease. He became unwell on December 21, was admitted to hospital on Christmas Day with severe pneumonia, and died this afternoon having tested positive for the H5N1 virus. The 39-year-old is known only by his surname Chen and lived in the city of Shenzhen, just across the border from Hong Kong. [Source: Lee Moran, The Independent, December 31, 2011]
“Guangdong's official newspaper, the Southern Daily, said 120 people who had contact with him had not developed signs of sickness. During the month prior to his fever, it said he had no direct contact with poultry and had not travelled out of the area. The news comes a week after two dead birds tested positive for the same virus in Hong Kong, which is separated from Shenzhen by a small river. And about 10 days ago Hong Kong culled 17,000 chickens at a wholesale poultry market and suspended all imports of live chickens from mainland China for 21 days after a dead chicken there tested positive for the H5N1 virus. [Ibid]
“In recent years, the virus has become active in various parts of the world, mainly in east Asia, during the cooler months. Authorities in China are worried about the spread of infectious diseases around this time when millions of Chinese travel in crowded buses and trains across the country to go home to celebrate the Lunar New Year. [Ibid]
Bird Flu in Japan, See Japan
Spread of Bird Flu
Initially cases of the H5N1 viruses were confined to Southeast Asia, but after it is detected in wild birds (bar-headed geese) in Qinghai Lake, China’s largest lake and major stopover for migratory birds, in February 2005 the virus rapidly spreads westward. Qinghai is a saltwater lake that sits at the crossroads of avian flyways to both Europe and Asia. The virus found there was slightly different than the one that was killing people in Vietnam at the time. In any case, By July and August 2005 it was in poultry in Russia and Kazakhstan and wild birds in Mongolia. In October it reached poultry in Turkey and Romania and wild birds in Croatia. In early 2006 there were human deaths in Turkey and Iraq and reports of the disease in Cyprus, Nigeria. Kuwait and Azerbaijan. In 2006, 65 outbreaks of H5N1 are reported worldwide killing a total of 115 people - the highest number to die from the disease in a single year.
In May 2005, Donald G. McNeil Jr. wrote in the New York Times, the bird flu virus in China “escaped in migratory birds going north and traveled across Russia, Europe and Africa. It became known as the Qinghai strain after the lake in Northern China where thousands of ducks and geese were found dead. (The older strain in Southern China and Southeast Asia is sometimes called the Fujian strain.) [Source: Donald G. McNeil Jr., New York Times, March 27, 2007]
“The Qinghai strain has a mutation known as PB2 E627K. (The abbreviation can be read this way: at position No. 627 on polymerase basic protein 2, the amino acid called glutamic acid, abbreviated by scientists as E, has been replaced by lysine, known as K.) The change helps the virus grow at the temperatures found in human noses, which are cooler than the insides of birds’ intestines. It is “characteristic of a gene that’s been in mammals,” said Dr. Robert G. Webster, a virologist at St. Jude Children’s Research Hospital in Memphis. “It says to me that it was in a mammalian species in China, and got back into ducks. But what species? We don’t know.” [Ibid]
“By March 2007 the Qinghai strain had reached about 50 countries. “To give a sense of how important such a tiny change can be: switching just one of the 1,255 amino acids in the SARS virus protein that attached to cells in the masked palm civet, a relative of the mongoose that is sold in wild-meat markets in Asia, allowed it to attach to human cells. After that discovery, the Chinese government ordered that all the 10,000 civets in captivity in Guangdong be killed, thus probably wiping out the disease everywhere except in bats. In avian flu, two mutations known to help viruses spread more easily---because they attach to the receptors in human noses and throats instead of those deep in the lungs---were found in outbreaks in Azerbaijan and Iraq in 2006. But those outbreaks were snuffed out. [Ibid]
H5N1 spread the quickest in the cooler winter months when birds are most likely come down with influenza. Scientists are not sure why this happens but suspect the reasons may be similar to why human influenzas appear and spread every year when temperatures drop. There were worries about large outbreaks during the time of the Chinese Lunar New Year and tet in Vietnam in February when large numbers of people travel and are packed close together on trains and buses and in stations and large amounts of poultry are sold live in markets, slaughtered, handled and eaten. In 2004 and 2005 bird flu first emerged in January and spread rapidly in February
The first case of bird flu found on a poultry farm in Britain occurred in February 2007 at a Bernard Matthew farm in Norfolk, England. About 160,000 turkeys were culled after the virus was detected It later was revealed the firm had been warned several times about hygiene lapses at the site. In March 2006, in the first case of bird flu in Britain, H5N1 was found in a wild swan in Scotland.
As of 2007, the only human bird flu cases in Africa outside of Egypt were in Nigeria and Djibouti. At that time there were some human cases in the Middle East but none in Europe, where both wild birds and poultry were infected. As of 2007 there were no reported cases of bird flu among humans or birds and scientists were testing birds near the Bering Strait to see if any were carrying the disease.
Key Factors Behind Bird Flu Outbreaks
Will Dunham of Reuters wrote: “In Ducks, people and rice paddies are the primary forces driving outbreaks of avian influenza in Thailand and Vietnam, and the number of chickens is less pivotal, scientists with U.N. Food and Agriculture Organization experts who looked at three waves of H5N1 bird flu in Thailand and Vietnam in 2004 and 2005, said. They used computer modeling to study how various factors were involved in the spread of the virus, including the numbers of ducks, geese and chickens, human population size, rice cultivation and local geography. [Source: Will Dunham, Reuters, March 27, 2008]
“Even though Thailand and Vietnam addressed the outbreaks in different ways, the researchers found that the numbers of ducks and people, and the extent of rice cultivation were the most important contributing factors underpinning the outbreaks. "This provides better insight on where and when the H5N1 risk is highest, so it's possible to better pinpoint where to look for the virus or where to expect flare-up of disease and also when to expect it," Jan Slingenbergh, senior veterinary officer for the Food and Agriculture Organization, said in a telephone interview. "It helps to better target the interventions," he added. Monitoring duck populations for the H5N1 virus and tracking rice farming by satellite are the optimal ways to predict an outbreak's distribution, the researchers said. They added that their model also can be extended to Laos and Cambodia, where there are similar land use patterns. [Ibid]
“Avian influenza has been closely linked to chickens in the past, but the study, published this week in the journal Proceedings of the National Academy of Sciences, found the number of chickens to be less important as a predictor. "In the past in Vietnam, there have been major (bird) vaccination exercises countrywide, which is an enormous effort in terms of logistics and time and effort and staff requirements," Slingenbergh said. "And there is fatigue, also, among the farmers and veterinarians. And if it's now possible to better time and localize the efforts, that is a major efficiency achievement." The researchers said there are close ties between duck grazing patterns and rice cropping intensity. They said ducks feed mainly on leftover rice grains in harvested paddy fields, so free-ranging ducks may go to many different sites following rice harvest patterns. [Ibid]
Weaker Form of Bird Flu Emerges in Turkey
Reporting from Ankara, Elizabeth Rosenthal wrote in the International Herald Tribune, “Two young brothers, ages 4 and 5, who have tested positive for the dreaded H5N1 avian virus, were being closely watched at Kecioren Hospital here today, although neither has exhibited any symptoms of the disease. Doctors are unsure whether they are seeing for the first time human bird flu in its earliest stages, or if they are newly discovering that infection with the dreaded H5N1 virus does not always lead to illness. A study released in the Annals of Internal Medicine suggested that the H5N1 virus could cause a wide spectrum of disease, but that doctors in Asia might only detect the severest cases, the ones that were hospitalized. The four children in Ankara bolster that suggestion.[Source: Elizabeth Rosenthal, International Herald Tribune, January 10, 2006]
“In any case, the highly unusual cluster of five cases detected here in Turkey's capital over the last three days - all traceable to contact with sick birds - is challenging some of the doctors' assumptions about bird flu and giving them new insights into how it spreads and causes disease. Since none of the five have died, it is raising the possibility that human bird flu is not as deadly as currently thought, and that many mild cases may have gone unreported. "The two brothers are a very interesting finding that may for the first time give us a chance to monitor the human response to the disease," said Dr. Guénaël Rodier, who is leading a World Health Organization team now in Turkey. [Ibid]
“The bird flu outbreaks and infections that have beset this country in the last week are leaving international scientists perplexed on many fronts. Turkey is the first country outside east Asia to have human cases, and the first one anywhere to have so many separate animal outbreaks simultaneously. In one week, Turkey announced 15 confirmed human cases of H5N1; Asia has seen only about 140 in the space of five years. In that same week, Turkish agriculture authorities announced bird outbreaks in 16 cities, from Aydin near Istanbul to Van in the far east; in Asia outbreaks have occurred more sporadically. "We are not yet sure of the mechanism," said Keith Sumption, an expert with the United Nations Food and Agriculture Organization in Rome. A senior scientist from that group is scheduled to arrive here Wednesday. [Ibid]
“On the human side, the five cases in Ankara hospitals are different from those in most of Asia: First, four of the five display only mild symptoms, or no symptoms at all. Also, although all five have had some recent contact with birds, Dr. Rodier said, they are people who live on the fringes of a major city, not farmers or people who keep birds in their backyards. [Ibid]
“The group includes two sets of brothers: The pair who show no symptoms at all, as well as another set of siblings who developed mild symptoms after contact with gloves that had been used to dispose of a dead duck. The fifth case is a 65-year-old man, who comes from inside the city itself, who the Turkish health ministry says had "close contact with a chicken," without elaborating on the details. [Ibid]
“In Ankara - where the government has been sending out vans with loudspeakers urging people to report symptoms and avoid contact with animals - even people with mild symptoms are being checked for bird flu, meaning that milder cases are more likely to be detected than they are in Asian countries. "I'm sure that part of the explanation for the high number of case in Turkey is better surveillance," a W.H.O. spokeswoman in Geneva, Maria Cheng, said. Residents of this urban district said almost nobody here keeps birds, instead buying poultry at the supermarket. Still, even in Turkey's cities, there are poultry to be found. One resident, Ibrahim Ercan, standing in a pool of blood from the day's slaughter, admitted that he kept some chickens in his backyard, "mostly as pets, to create a farm-like atmosphere." [Ibid]
“The huge number of animal outbreaks across the country is also perplexing, scientists said. One theory is that migrating birds seeded the disease in various areas in late December. But that is contradicted by the fact that no outbreaks have been reported in adjacent countries where the birds would also have passed. Another possibility is that poultry-selling practices in Turkey contributed to the spread. In Dogubyazit City, home to 4 of Turkey's 15 human H5N1 cases, people said the big chicken farms often send huge trucks of old birds to the town, selling them to poor farmers for one Turkish lira, or about 60 cents. The last truck arrived two or three weeks ago, they said. If even one bird on such a truck had bird flu, experts said, it could have quickly infected the others on board, disseminating H5N1 to many villages. "We are very keen to support the Turkish authorities in exploring the details of the movements of poultry," Mr. Sumption said. [Ibid]
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Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, The Guardian, National Geographic, Smithsonian magazine, The New Yorker, Time, Newsweek, Reuters, AP, AFP, Wall Street Journal, The Atlantic Monthly, The Economist, Global Viewpoint (Christian Science Monitor), Foreign Policy, Wikipedia, BBC, CNN, NBC News, Fox News and various books and other publications.
© 2008 Jeffrey Hays
Last updated November 2012