Swine flu. Bird flu. Mad cow disease. SARS. These diseases have all spread from animals to humans in one form or another.

But animals aren't to blame for outbreaks of animal-borne diseases – humans are.

Our demand for meat means pigs, turkeys, chickens, cows and other animals must be mass produced in crowded, feces-ridden factory farms like the one in Mexico that is suspected of starting the current swine flu outbreak. These farms are incubators for disease.

Precautions such as stockpiling antiviral drugs, closing schools, suspending travel and practicing good hygiene are necessary to help stop the spread of swine flu, but we need to take one more significant measure to prevent future epidemics of animal-borne diseases: Stop raising animals for food.

The meat industry's cost-cutting practices-cramming tens of thousands of animals into filthy sheds and slaughtering them on killing floors that are contaminated with feces, vomit and other bodily fluids-allow diseases such as swine flu, mad cow disease and avian flu to flourish.

Authorities believe one of Mexico's largest pork producers, Granjas Carroll, which is a subsidiary of U.S.-based Smithfield Foods (the largest pork producer in the world), may be the source of the swine flu outbreak.

Swarms of flies hover above the lagoons where Granjas Carroll discharges hog feces, and area residents have long complained the waste is tainting the water, polluting the air and causing respiratory infections.

In April, residents told reporters that more than half of the town's population was sick and three children under the age of 2 had died.

While it's easy to point fingers at Granjas Carroll and Mexico, disease-ridden animal factories can be found all over the world.

According to the Centers for Disease Control and Prevention, studies have shown that 30 to 50 percent of pigs raised for food in the U.S. have been infected with some strain of swine flu.

Hans-Gerhard Wagner, a senior officer with the U.N.'s Food and Agriculture Organization, has called the "intensive industrial farming of livestock" an "opportunity for emerging disease."

Other harmful organisms, including salmonella, campylobacter, listeria and E. coli, also spread from animals to people. E. coli is found in the feces of farmed animals and often sprays in every direction when animals are eviscerated at slaughterhouses.

A study published in the journal Nature revealed that not only are U.S. meat and dairy products more commonly contaminated with E. coli than other foods are, they also contain a substance that can raise the risk of E. coli infection.

Although health officials have been quick to point out people can't get swine flu from eating pork, they have failed to hammer home one significant detail: Raising pigs for pork is what puts us at risk for swine flu in the first place.

The fewer pigs, chickens and other animals we raise for food, the fewer animal-borne diseases there will be.

It's that simple.

And since meat is high in saturated fat and cholesterol and can cause heart disease, diabetes, certain cancers and a host of other health problems.

We would all be better off if we stopped eating it today.