The last three influenza pandemics have all originated in Asia – the 1957 Asian flu, the 1968 Hong Kong flu and now this year’s SARS flu, which also has been traced to China’s southern Guangdong province, which includes Hong Kong.
Why do these virulent new viral strains come out of South China?
Some virologists implicate the farming practices common there. In southern provinces of China, farmers raise hens, ducks, pigs and fish in one integrated system. They use the droppings and leftover food from the pigs to feed the fowl. The fowl droppings, in turn, help fertilize the fish ponds.
While it sounds like a perfect system, raising three different species with no waste, the species may be exchanging viruses among themselves through the feces.
The birds can pass avian flu viruses to swine, where the two viruses commingle and form a new strain that is passed back to the farmers, whose immune system cannot fight the new virus, as the theory goes. The pigs, which have a genetic make-up more like humans, act as the mixing vessel.
The 1968 Hong Kong flu strain, at least, was traced back to ducks. That flu and its cousins have killed more than 250,000 Americans, public-health officials estimate.
British zoologist Ernest Naylor and German virologist Christoph Scholtissek first made the connection and warned of future superflu outbreaks from such Chinese agricultural techniques in a 1988 article in Nature.
Regarding SARS, “the most likely scenario is that it has been circulating in another species in southern China, and human beings came in contact with it this past autumn, perhaps in an agricultural setting,” said Dr. Stephen Morse, author of “Emerging Viruses.” “It is interesting that this part of Asia is the same geographic area from which most known influenza pandemics have arisen.”
The federal Centers for Disease Control is not ready to commit to the theory that China’s farming practices are to blame for SARS, although some say the reluctance has more to do with international politics and diplomacy than medicine.
“I can’t confirm that it has anything to do with the agricultural industry,” said CDC spokeswoman Karen Hunter in a phone interview from Atlanta. “We don’t have any concrete reasons why influenza sometimes comes out of Asia.”
She notes that major viruses have mutated outside of Asia, too. For example, the last century’s first flu
pandemic, called the “Spanish flu,” which struck in 1918, came out of Spain, though recent research has traced the virus strain back to China.
“Even though the last two flu pandemics did come out of Asia,” she said, “Asia is not the only place where we see flu viruses mutating and changing.”
But one U.S. public-health official, an epidemiologist, says the CDC has long acknowledged the theory’s merits.
“Certainly such old-world agriculture is not the best of ideas,” he said. “The primary reason we in the U.S. are concerned about proper disposal of human and animal wastes is for reasons of public health, not for aesthetic ones.”
He added they don’t yet understand that in mainland China, which is still run by a communist government.
Chinese dissident Harry Wu says Chinese farmers also feed human waste to pets, whose waste is fed to livestock.
“It is very common in China, in the rural areas, for the dog to clean up the human bowel (movement),” he said in a WorldNetDaily interview. “You know, the baby makes bowel on the floor (and) the dog will come right in and eat it up.”
“The whole environment is like that,” Wu added.
He also cited the Chinese people’s indiscriminate, omnivorous diet as a possible concern.
“I don’t know if these animals are one of the reasons (for SARS), but it is true in the southern part of China that they eat all kinds of animals,” Wu said. “We make a joke that they eat everything that flies except for airplanes, and they eat everything with legs except the tables – snails, turtles, chickens, raccoons. Even some right now are eating the fetus, unborn babies, as a delicacy. That is cannibalism.”
Wu notes recent speculation by a Russian scientist who posits that the SARS virus is man-made, invented by a Chinese military lab as a biochemical weapon.
“I’m not sure about that,” he said, “but I wouldn’t be surprised” if it’s true.
Interestingly, influenza fatality rates are virtually unknown. That’s because there are no concrete figures for the number of people who get the flu each year to calculate against the number of reported deaths, Hunter says. Many who come down with the flu don’t visit the doctor, and therefore don’t show up in the statistics.
But generally, the fatality rate for the common flu is thought to be about 15 percent, which may be inflated given the incomplete data for the denominator. The fatality rate for SARS, by comparison, is estimated to be running between 4 percent and 10 percent so far.