31.   Extracting it can take months, and if the worm breaks while emerging, it can cause infection.

32.   For example, enterococcus, which sometimes causes urinary tract infections, has been treated with the antibiotic vancomycin.

33.   Four in five new infections were caused by needle-sharing among drug users, the deputy director, Inga Upmerce, said.

34.   For instance, drinking the contaminated water could cause gastrointestinal diseases, she said, and getting it on the skin could cause infections.

35.   Gaining a major new insight into the nature of Lyme disease, biologists have decoded the entire DNA of the bacterium that causes the infection.

36.   He also tried to help unravel the mystery of why some viral infections end after a few days while others cause persistent infection.

37.   He has already found evidence that caliciviruses, which can cause diarrhea, periodically re-emerge from the oceans, causing new infections.

38.   His studies were at first regarded as heretical because they invoked a bizarre concept that infection could be caused by an agent without genetic material.

39.   Hepatitis B also can cause chronic infections, but there is a vaccine against that pathogen.

40.   How can you tell if the infection is caused by a yeast?