The outbreak of a new strain of deadly human bird flu--H7N9--is spreading so rapidly in eastern China that Shanghai authorities are considering a permanent ban on the sale of live poultry in the city, according to the South China Morning Post.
Just days ago, reports in American and European publications indicated that only three people had died from a new strain of avian influenza. However, Chinese authorities announced on April 10, that the virus had claimed its eighth and ninth fatalities--an 83-year-old man from Suzhou, Jiangsu, who died a week after testing positive for the virus, and a 35-year-old woman from Chuzhou, Anhui.
In all, twenty-nine people have now been diagnosed with bird flu, according to the SCMP report. Some of the patients have died of severe pneumonia brought on by the virus.
The situation is so serious that Sun Lei, director of Shanghai's Agriculture Commission, announced consideration of a permanent ban for the live-poultry trade after 20 samples taken from "wet markets" tested positive for H7N9, according to the Oriental Morning Post.
Cities in Zhejiang and Jiangsu have already temporarily closed “wet markets,” according to the report. Permanent bans could force a change in Chinese culinary tradition, with many residents preferring to buy live poultry and have it butchered in a market or at home.
SPECULATION ON ORIGIN/SPREAD OF THE DEADLY DISEASE
The first two bird flu fatalities in March were reportedly men aged 27 and 87, infected in the city of Shanghai, where thousands of dead pigs washed up on the banks of the Huangpu River last month.
A third victim died in a hospital in Hangzhou city on March 27. At least five of the victims were in a critical condition in a hospital in Nanjing, according to the Daily Mail report. Shanghai, Nanjing and Hangzhou are all close to each other in eastern China.
All the casualties were diagnosed with the H7N9 form of influenza, a type which had not previously been known to infect human beings, medical authorities state. Flu experts around the world are reportedly studying samples isolated from the patients to assess its human-pandemic potential.
Pulitzer Prize-winning science writer Laurie Garrett has suggested that the virus that killed the pigs could be linked to the new strain of bird flu. She speculates that the deadly outbreak may be linked to the unexplained deaths of thousands of pigs, ducks and swans which local residents in Shanghai began to spot floating down the Huangpu River on March 10.
Within a few days the carcasses of thousands of dead ducks were found in the Nanhe River in the southwestern Chinese province of Sichuan.
Alarmingly, by the end of the month, the dead bodies of at least 20,000 pigs as well as tens of thousands of ducks and swans had been washed up on riverbanks across China, reports the Daily Mail.
Although the cause of the deaths of the animals has not yet been confirmed, most people assumed that China's notoriously polluted waterways are responsible.
Tests at the Beijing Center for Disease Control and Prevention on some of the dead pigs later revealed evidence of PCV-2, a virus that is harmless to human beings, as well as birds. However, PCV-2 it is only supposed to be fatal to fetuses and newborn piglets and the pigs tested were all adult, according to reports.
RAPID MUTATION OF H7N9 BIRD FLU COMPARED TO HIV
The new bird flu could be mutating up to eight times faster than an average flu virus around a protein that binds it to humans, a team of research scientists in Shenzhen warn, according to the South China Morning Post.
Dr He Jiankui, an associate professor at South University of Science and Technology of China, states that the team scrutinized the genetic code of the virus obtained from mainland authorities, and discovered a protein (haemagglutinin), that plays a crucial rule in binding the virus to an animal cell, such as respiratory cells in humans, and bores a hole in the cell's membrane to allow entry by the virus. There was a rapid mutation in the evolutionary development of the virus that makes it very hard to predict, he explained.
"It happened in just one or two weeks. The speed may not have caught up with the HIV, but it's quite unusual for a flu."
LEADING SCIENTIFIC WRITER PROPOSES EXPLANATION
CFR Senior Fellow for Global Health Laurie Garrett proposes on the foreignpolicy.com website:
“One very plausible explanation for this chain of Chinese events is that the H7N9 virus has undergone a mutation -- perhaps among spring migrating birds around Lake Qinghai.
“The mutation rendered the virus lethal for domestic ducks and swans.
“Because many Chinese farmers raise both pigs and ducks, the animals can share water supplies and be in fighting proximity over food -- the spread of flu from ducks to pigs, transforming avian flu into swine flu, has occurred many times.
“Once influenza adapts to pig cells, it is often possible for the virus to take human-transmissible form.
“That's precisely what happened in 2009 with the H1N1 swine flu, which spread around the world in a massive, but thankfully not terribly virulent, pandemic,” Garrett writes.
Chinese authorities are dismissing such speculation and insist that the H7N9 outbreak is not linked to the animals found dead in the rivers.
Yin Ou, deputy director of the Shanghai Municipal Agricultural Committee, reported 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.
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 from human to human. So far, this lack of human-to-human transmission also appears to be a feature of the H7N9 strain.
BIRD FLU SO CONTAGIOUS IT COULD KILL MILLIONS
The first cases of bird flu were diagnosed in 1996, and a year later the disease spread to humans in Hong Kong. It moved throughout Asia and was later reported in Europe.
Medical experts believe that, because it is so highly contagious, a mutated form of bird flu eventually could cause the world's biggest pandemic threat and conceivably kill between 5 million and 150 million people.
The Agriculture Ministry said it had yet to find any animals infected with H7N9, although it is possible it has been brought to China by migratory birds. 'We still don't know the mode of transmission or host (of the virus),' said Gregory Hartl of the World Health Organization.
SHARED REPORTING ESSENTIAL
Much of the concern in the past was that Chinese officials sought to cover up some disease outbreaks. In fact, online speculation about recent flu deaths in Shanghai was quickly muzzled prior to the confirmation of H7N9, reported China’s Southern Metropolis Daily. Posts about the deaths disappeared or were drowned out by netizen discussion of the thousands of dead pigs found in a Shanghai river, the paper reported..
However, health authorities report that, since the H7N9 cases have been identified, China is being transparent in reporting.