Correspondence

The Outbreak of Conjunctivitis at Dartmouth

N Engl J Med 2003; 348:2577-2578June 19, 2003

Article

To the Editor:

Martin et al. (March 20 issue)1 and, in her Perspective article, Zuger2 correctly observe that the “wired” Dartmouth campus provided effective electronic means of collecting data that might have helped contain the outbreak of conjunctivitis in early 2002. The infection spread rapidly among students, whereas health center staff members were spared. In fact, the omnipresent computers on campus may have been an important risk factor for infection among the students. The Dartmouth campus has terminals and keyboards in all well-traveled areas, including the dining halls. Most Dartmouth students (I was a member of the class of 2002) use these popular “blitz” terminals between 10 and 20 times a day. It goes without saying that the students who use these terminals are not likely to have washed their hands. The technology that helped to trace and contain this outbreak may well have been a major vector for its spread.

Emily K. Feingold
New York University School of Medicine, New York, NY 10021

2 References

1. 1

   Martin M, Turco JH, Zegans ME, et al. An outbreak of conjunctivitis due to atypical Streptococcus pneumoniae. N Engl J Med 2003;348:1112-1121
   Full Text | Web of Science | Medline

2. 2

   Zuger A. Medical detection in the 21st century. N Engl J Med 2003;348:1079-1080
   Full Text | Web of Science | Medline

Author/Editor Response

We did consider the hypothesis that shared computer terminals fostered transmission. Early in the investigation, samples were collected from 40 to 60 public terminals and other commonly touched objects (e.g., the shiny nose of a prominent bronze bust) and were cultured for Streptococcus pneumoniae on blood-agar plates.1 No samples yielded pneumococci. Subsequently, one investigator conducted an inoculation experiment in which he dipped his fingers in Todd–Hewitt broth containing the outbreak strain and typed on a keyboard; the strain was recovered five hours later from keyboard specimens incubated in enrichment-broth mediums.

The outbreak strain may have been spread in part through the use of public terminals. If so, cultures taken from keyboards during the outbreak may have yielded no growth because the specimens were collected at a time when the terminals were not contaminated or because enrichment broth may be necessary for recovering pneumococci from surfaces. Conversely, the inoculation experiment may not have recreated real-life keyboard contamination, and terminals did not facilitate transmission. In either case, outbreak-control measures, including the distribution of hand-washing messages and alcohol-based hand gel, were undertaken in an effort to reduce any role of hand contamination in transmission.

Cynthia G. Whitney, M.D., M.P.H.
John Elliott, Ph.D.
Centers for Disease Control and Prevention, Atlanta, GA 30333
cwhitney@cdc.gov

Joseph D. Schwartzman, M.D.
Dartmouth–Hitchcock Medical Center, Hanover, NH 03756

1 References

1. 1

   Pryor JH, Martin MT, Whitney CG, Turco JH, Baumgartner YY, Zegans ME. Rapid response to a conjunctivitis outbreak: the use of technology to leverage information. J Am Coll Health 2002;50:267-271
   CrossRef | Web of Science | Medline