Journal Article

Transmission Potential of Smallpox: Estimates Based on Detailed Data from an Outbreak

Martin Eichner and Klaus Dietz

in American Journal of Epidemiology

Published on behalf of Johns Hopkins Bloomberg School of Public Health

Volume 158, issue 2, pages 110-117
Published in print July 2003 | ISSN: 0002-9262
Published online July 2003 | e-ISSN: 1476-6256 | DOI:
Transmission Potential of Smallpox: Estimates Based on Detailed Data from an Outbreak

More Like This

Show all results sharing this subject:

  • Public Health and Epidemiology


Show Summary Details


Recent discussions on the use of variola virus by bioterrorists have rekindled interest in the parameters that govern the transmissibility of smallpox. Here, the authors estimate by maximum likelihood the parameters of the spread of smallpox from historical data on an epidemic in 1967 in the town of Abakaliki, Nigeria, afflicting a religious group that refused vaccination. According to the authors’ estimates, 79.9% (95% confidence interval (CI): 63.6, 87.9) of the infectious contacts occurred within the compounds of the cases and 93.3% (95% CI: 80.6, 98.8) among compound members and other close contacts. Each case had 0.164 (95% CI: 0, 1.31) sufficiently close contacts on average during the fever period that preceded the rash and 6.87 (95% CI: 4.52, 10.1) sufficiently close contacts during the whole course of infectivity. These results support the widely held belief that smallpox spreads slowly, mainly among close contacts, and that infectivity before the onset of rash was negligible.

Keywords: disease outbreaks; infection; inference; models, statistical; smallpox; variola virus; Abbreviations: CI, confidence interval; FTC, Faith Tabernacle Church.

Journal Article.  4200 words.  Illustrated.

Subjects: Public Health and Epidemiology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.