21.   Carriers can also infect other people.

22.   Carriers of the highly infectious virus can infect other people even without having symptoms themselves.

23.   Doctors at the center said he may have infected several people who came into contact with him.

24.   Eight people have been infected with the disease and one man has died.

25.   Eleven people have been infected with inhalation anthrax, a biological agent mysteriously released through the mail in a second wave of terror that began late September.

26.   Four people became infected on a United Airlines flight from Chicago to Honolulu last spring, when they were seated near a woman with the disease.

27.   Four people have been infected and two have died.

28.   Four people have been infected and two have died, one last Friday.

29.   He said it was not clear if both strains are in all infected cells when people are doubly infected.

30.   How many people are infected in the United States and has the rate changed in recent years?