More than 20 villagers in Zimbabwe have contracted anthrax after butchering and eating infected livestock, according to various news reports. In all cases, the people affected required hospitalization although there have been no fatalities to date.

Dr. Mohammed Khaled, the District Medical Officer for the region, advised the public to abstain from eating meat from livestock when the cause of deaths is unknown, according to The Global Dispatch online news service. The outbreak was discovered by veterinary authorities after affected villagers sought medical care for their infections.

Another veterinary officer, Dr. Kupa Hwana, said that because farmers did not report the death of cattle, it became too late for vaccine intervention. Farmers and herders in the region are being actively discouraged from slaughtering sick animals, and advised to properly bury dead ones to avoid spreading the disease.

According to an investigation by the UK newspaper Daily Mail, more than 165 wild animals, including 88 hippopotamuses, have died amid a recent outbreak of anthrax in Zimbabwe. Along with the hippos, the death toll included 45 buffaloes, 30 elephants and two kudus in the country’s northern Mana Pools National Park, one of Zimbabwe's most famous preserves and a World Heritage wetlands conservation site that is home to numerous lions, water buffalo and leopards, as well as hippos.

Nor is the outbreak in Zimbabwe an isolated case of an anthrax outbreak among African game animals. In July 2010, the government officials in Uganda confirmed that 82 hippos were among at least 90 animals that had been killed by the disease. Officials there said the affected animals came into contact with anthrax spores after drinking water from an infected river in that country’s Queen Elizabeth National Park.

From spores to

Anthrax, of course, is caused by the Bacillus anthracis pathogen and is a highly infectious disease that affects hoofed animals, especially cattle. Other common herbivores susceptible to the disease include sheep, goats, horses, camels and deer.

The disease infects mammals that come into contact with the spore-forming bacteria, principally through the respiratory system. Those spores can sometimes lie dormant for years before becoming active, which is one of the reasons anthrax is such a pernicious disease. In the Zimbabwean outbreaks, affected animals apparently came into contact with the corpses of other animals killed by the infection.

That occurs because when conditions become favorable the spores can germinate into colonies of bacteria. A grazing cow will ingest spores that then germinate, multiply and eventually kill the animal. Those bacteria can then re-form spores inside the carcass, which contaminates the soil and eventually infects other animals.

Although there are no reports of person-to-person transmission of anthrax, humans are also susceptible when directly exposed to the bacterial spores, as Americans shockingly learned from the “weaponized anthrax” attacks on U.S. government and Postal Service officials following 9/11.

People can also contract anthrax by handling contaminated animals or animal products—the vector that originally prompted the famous French chemist Louis Pasteur to develop a vaccination for anthrax in the 1870s—or from consuming undercooked meat of infected animals.

The lesson here is this: For all the criticism of modern livestock production, for all the griping about the (alleged) environmental impact of confinement production, no one’s going to contract anthrax from the cattle that enter the food supply in any country using such methods.

For all its pastoral cachet and the praise lavished on indigenous herders by anti-industry activists, the cattle in many parts of the world raised on “natural” methods of animal husbandry face the threat of anthrax and other diseases that are rare or virtually unknown in the developed world.

That’s an issue of little concern to most Americans, since other than a terrorist attack, there’s practically no chance any of us will ever be hospitalized for exposure to anthrax.

That’s a shame—the lack of concern, that is, not our immunity from some of the worst infectious diseases afflicting millions elsewhere in the world.

And it’s one more reason why 21st century animal agriculture represents a monumental advance over the primitive systems still in place across much of the rest of the world.

The opinions expressed in this commentary are solely those of Dan Murphy, a veteran food-industry journalist and commentator.