Abstract
The World Health Organization has recommended repeat mass drug administration as part of their global initiative to eliminate blinding trachoma by the year 2020. The efficacy of repeat treatment will be tested empirically, but the results will not be available for many years, and recommendations for the necessary frequency of treatment are needed immediately. We have developed a mathematical model that uses available epidemiological data from a variety of countries. We recommend, based on our analysis, that in areas where trachoma is moderately prevalent (<35% in children), it should be treated annually, but hyperendemic areas (>50% in children), it should be treated biannually.
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Acknowledgements
We thank E. Ziv, H. Gershengorn, K. Koelle, S. Osaki, J.P. Whitcher and J. Schachter fokr comments and A. Edgecombe for technical assostance. We are grateful to the National Institute of Allergy and Infectious Diseases (Grants K08 Al 01-441-0 and 1R01 A1 41935).
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Lietman, T., Porco, T., Dawson, C. et al. Global elimination of trachoma: How frequently should we administer mass chemotherapy?. Nat Med 5, 572–576 (1999). https://doi.org/10.1038/8451
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DOI: https://doi.org/10.1038/8451
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