Joan Ponegan, age 11, of Flushing, New York, for her question:

What is foot and mouth disease?

This dreaded disease is caused by one of the smallest virus germs known to science. It attacks the cleft footed animals and can be transmitted from the stricken animals to human beings. In severe epidemics, foot and mouth disease may be fatal to 70% of the infected animals. And those cleft footed creatures include our cows and cattle, our sheep and pigs. Farmers and ranchers dread an outbreak of the fearful foot and mouth or hoof and mouth disease and when it occurs the strictest measures are taken to stop it from spreading. Herds of infected animals are killed and burned or buried in quicklime. Their living quarters are burned or treated with strong disinfectants. The men who handle the sad job wear germ proofed rubber clothing.

A severe outbreak recently occurred in England and the U.S. has quarantined and treated nine infected farm areas in the past century. An infected animal becomes sick after two days and the feverish disease progresses fast. It is highly infectious and symptoms soon appear in the whole herd. The joints of the suffering animals become stiff and blistering sores appear in their mouths and around their hoofs. At present, the only known treatment is to destroy all the suspected animals and place the epidemic area under strict quarantine.