31.   Health officials are testing local water towers to try to determine the source of the infection.

32.   Heath officials tested the letter but found no dangerous substances.

33.   Health officials are testing water towers to try to determine the source of the infection.

34.   Hospital officials were testing patients who had come into contact with the girl, Ms Mou said.

35.   In Venezuela, health officials were testing a powder found Tuesday in an envelope sent to a Caracas woman.

36.   Kumar said migratory birds could be the source, and officials would test any dead birds that are found.

37.   Mayor Rudolph Giuliani said officials were testing a number of media mailrooms around the city after the tests began Monday.

38.   Officials also were testing a female mail carrier and male maintenance worker in Trenton who reported possible symptoms of anthrax, Esposito said.

39.   Officials at the Department of Health said Monday they believe the patient has the virus, although federal officials are also testing him.

40.   Officials are testing affected areas for any increase in bacteria levels.