Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: SUNDAY, April 16, 1995                   TAG: 9504180025
SECTION: HORIZON                    PAGE: D-4   EDITION: METRO 
SOURCE: KNIGHT-RIDDER NEWSPAPERS
DATELINE: WASHINGTON                                LENGTH: Short

PHYSICIANS WORRIED THAT GERMS ARE REFUSING TO DIE

The cause of their concern is disease-carrying germs - bacteria and viruses - that have recently developed resistance to the very drugs that used to kill them.

For years, doctors successfully treated common infections like streptococcus, tuberculosis, influenza and pneumonia with antibiotics like penicillin, ampicillin, tetracycline, erythromycin and their many cousins.

In a growing number of cases now, however, the germs refuse to die.

How do they develop this amazing resistance? Scientists say it's pure Darwinian evolution.

Say a patient is infected with streptococcus. Millions of bacteria multiply in his body. Penicillin kills almost all of the invaders.

But a chance mutation in the genetic makeup of a single bacterium makes it invulnerable to the drug. That lone survivor divides and redivides, over and over, until it emerges as a new, antibiotic-resistant strain of streptococcus.

In evolutionary terms, that hardy species has been selected for survival over its weaker relatives. In bacteria, the process can take days, not centuries.

This is not science fiction. Jim Henson, developer of the Muppets, died in 1990 of a highly toxic, mutant variety of streptococcus that penicillin could not control.