VOA常速英语2008年-Antibiotic-Resistant Bacteria Poses Threat to P

There is growing concern around the world over illnesses caused by new antibiotic 1-resistant 2 bacteria, or so-called "superbugs", and the decreasing effectiveness of antibiotics 4 to treat infections. Earlier this month, the National Commission on Industrial Farm Animal Production presented its findings to a group of U.S. lawmakers and journalists. As Ruth Reader reports from Washington, commission members outlined the dangers to humans when bacteria is transferred from farm animals to the general population.

In the last decade several "super bugs 3" have emerged worldwide, causing concern among doctors and civilians 5.

Dr. Robert Lawrence, a professor of public health at Johns Hopkins University, says,  "they're getting into our water sources; they're getting into soils; and they're getting into the air."

Along with two members of the National Commission on Industrial Farm Animal Production, he described how the production of meat and poultry 6 plays a big role in the spread of antibiotic resistant bacteria.

Most farms in the U.S. today are not small family farms, but large-scale industrial operations. Researchers say farmers add antibiotics to the animal feed to prevent disease from spreading through the livestock 7. Animals raised for their meat are kept in very tight living quarters where it is easy for disease to spread.

This frequent use of antibiotics causes bacteria to develop a resistance to the drug. That means not only does the meat carry the antibiotic resistant bacteria, but so does the animal waste.

Dr. Lawrence says hogs 8, for example, produce six to seven times as much waste as humans. The waste is sometimes kept in large manure 9 lagoons 10, which can flood and overflow 11 when it rains or snows. Other times, farmers spray animal waste onto fields as a fertilizer, but they often over-saturate the fields.

"Every year 357,000 tons of chicken waste from the chicken farms, owned by the integrators operating out of Arkansas and Oklahoma, is spread on the land, (and) runs-off because it is so excessive it can't be absorbed by growing plants and gets into shallow wells, into the drinking water, and into the Illinois River," he said.

There are other ways resistant bacteria can infect humans. Dr. Michael Blackwell, President and CEO of the Blackwell Group, explains, "Run-off onto, let's say a spinach 12 field, or using that feces as a fertilizer, is one way to transfer to a non-meat type food articles."

And, as Harvard Associate Professor Mary Wilson explains, the problem is not confined to the United States, "The general issue of antimicrobial resistance is a global problem and traveling, moving populations also means that there are resistance genes 13 in bacteria, for example, that emerge in one part of the world, in fact, they can be carried to another part of the world."

Antibiotic-resistant bacteria is not only global, it's in the soil and water. Dr. Mary Torrence, a food safety expert at the U.S. Department of Agriculture, says there is no easy fix. "We haven't figured out what will reduce antibiotic resistance. There's been a lot of efforts internationally as far as reducing antibiotics in animals and in people. And we have yet to find out what impact that has at the public health level."

So far, Dr. Torrence says, there have been mixed results in research on organic farming. She says that even though organic farmers are not using antibiotics or growth hormones 14 on their livestock, antimicrobial bacteria is still present.

The Commission plans to release a full recommendation to Congress on how to deal with the problem of antibiotic resistance at the end of February.