This is the VOA Special English Agriculture Report.

Pigs in China's eastern Shandong Province receive a blue-ear disease vaccine

The government of China says much progress has been made in efforts to control the spread of blue-ear pig disease. Government officials said last week that forty-seven thousand pigs were infected in July. That was down more than fifty percent from the number reported for June.

The name for the virus comes from the fact that infected pigs can temporarily develop discolored ears. The scientific name is porcine reproductive and respiratory syndrome.

China has an estimated five hundred million pigs. An Agriculture Ministry spokesman said more than one hundred million pigs have been given vaccine to prevent the disease.

The spokesman said two hundred fifty-seven thousand pigs were infected with the virus this year. Sixty-eight thousand of them died. Many more were destroyed.

An Agriculture Ministry official said the outbreak involves a form of the virus that is unusually deadly to pigs.

Vietnam also has reported recent cases of blue-ear disease.

The disease causes reproductive failure in female pigs and breathing difficulties in young pigs. Older pigs may also be affected. Signs of the disease can include high fever and cases of pneumonia. Pigs weakened by the virus are more likely to get bacterial infections.

An outbreak of infectious disease killed as many as one million pigs in China last year. China's top veterinary health official said this past June that blue-ear disease was the cause of most of those deaths. China reported the outbreak to the World Organization for Animal Health last September.

The World Organization for Animal Health says the disease happens in most major pig-producing areas of the world. The disease was first recognized in nineteen eighty-seven in the United States. Three years later it appeared in western Europe and spread quickly.

The agency says the disease does not seem to affect animals other than pigs. Experts say they do not know of any cases of humans who have gotten the pig disease.

China is the world's largest producer of pigs. Supply shortages have driven up pork prices this year in China. Still, a Commerce Ministry spokesman said this month that China exported sixty-two thousand metric tons of pork in the first half of the year. That compared with pork exports of two hundred forty-six tons for all of last year.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. For more stories about agriculture, go to voaspecialenglish.com. I'm Faith Lapidus.