21.   French officials have said they would begin tests this month of cattle destined for human consumption to determine how widespread the disease has become.

22.   He also urged government measures to fight the spread of AIDS, warning that the disease could become a national security threat.

23.   Health care and sanitation have deteriorated throughout the former Soviet republics, and outbreaks of cholera and once-rare diseases have become increasingly common.

24.   Health researchers fear that if the program is not strictly followed, the disease could become resistant to the treatment.

25.   In many cases, patients die of other causes long before the prostate disease becomes life-threatening.

26.   Left unchecked, even a slow-acting spongiform disease could become a biological prairie fire, experts fear.

27.   Mad cow disease has become a huge concern in Europe, where beef sales have plummeted.

28.   Most of those immigrants were infected while living outside the United States, and the disease became active after they moved here, the CDC said.

29.   Pollution has led to increases in malignant tumors, and respiratory diseases have become the leading cause of death in rural areas, it said.

30.   Some forms of malaria have become resistant to preventive drugs, and the disease is becoming an increasingly serious problem in some parts of the world.