Infectious Diseases: Fighting Staph with Staph

The bacteria known as Staphyiococcus aureus are dreaded by doctors as a cause of dangerous and persistent infections in many parts of the body. Ironically, the kinds of “staph” commonly found in hospitals are the worst of all, because they have developed resistance to most of the antibiotics around them. They are spread, usually from wounds or boils, not only on patients’ linen, but also on nurses’ hands and surgeons’ breath, and even through air ducts. Newborn babies, with practically no resistance, are especially susceptible. Some hospital nurseries have been decimated by staph epidemics.

Doctors have tried everything they could think of to check staph, and now it appears that a good way to do it is to fight staph with staph. There are as many varieties of staph as there are breeds of dogs, and some are harmless while others are vicious. Researchers in Manhattan and Cincinnati got the idea that if they could “infect” newborn babies with a harmless strain, these germs might somehow prevent later invasion by dangerous strains.

In last week’s A.M.A. Journal, Pediatricians Irwin J. Light and James M. Sutherland reported how well the technique worked. They grew a gentle strain of staph, dubbed 502A, in soy broth, and swabbed a minute amount of the germ-laden fluid into the nostrils and on the unhealed navels of one-hour-old babies in Cincinnati General Hospital. The 502A “took”; air sampling and other tests showed that dangerous strains of staph soon disappeared from the nurseries. But the harmful strains reappeared after swabbing was stopped. Medical men call the staph v. staph process “bacterial interference,” and are not quite sure how it happens. Some suspect that interference may occur be cause one strain of staph utilizes some substance that the other strain needs in order to live, or that one strain produces something that kills the other.

The method is not recommended for routine, continuous use because some babies develop a rash from 502A. But it can be instituted whenever a virulent strain of “hospital staph” is detected in a nursery, and in at least six hospitals it has halted such invasions.