This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Lan, R. Articles by Reeves, P. R. Search for Related Content PubMed PubMed Citation Articles by Lan, R. Articles by Reeves, P. R.

Pandemic Spread of Cholera: Genetic Diversity and Relationships within the Seventh Pandemic Clone of Vibrio cholerae Determined by Amplified Fragment Length Polymorphism

Department of Microbiology, University of Sydney, NSW 2006, Australia

Received 11 May 2001/ Returned for modification 9 August 2001/ Accepted 15 October 2001

The seventh cholera pandemic started in 1961 and continues today. A collection of 45 seventh pandemic isolates of V. cholerae sampled over a 33-year period were analyzed by amplified fragment length polymorphism (AFLP) fingerprinting. All but four pairs and one set of three isolates were distinguished. AFLP revealed far more variation than ribotyping, which was until now the most useful method of revealing variation within the pandemic clone. Unfortunately, the ribotype variation observed is mainly due to recombination between the multiple copies of the rrn genes (R. Lan and P. R. Reeves, Microbiology 144:1213–1221, 1998), which makes changes susceptible to repeat occurrences and reversion. This AFLP study shows that particularly for the common ribotypes G and H, such events have indeed occurred. AFLP grouped most of the 45 isolates into two clusters. Cluster I consists mainly of strains from the 1960s and 1970s, while cluster II contains mainly strains from the 1980s and 1990s, revealing a temporal pattern of change in the clone. This is best seen in the relationships of the strains from Africa, which correlate with the epidemiology of epidemics on that continent. The data confirm independent introductions to Africa during the 1970s outbreak and reveal several other African introductions. In the 1991 cholera upsurge, isolates from the Southern and Eastern African epidemic focus are markedly different from those from the West African epidemic focus. An isolate from 1987 in Algeria was identical to the West epidemic isolates, suggesting that the strain was present in Africa at least 3 years before causing large outbreaks. These observations have major implications for our understanding of cholera epidemiology.

This article has been cited by other articles:

• Rolfs, A., Montor, W. R., Yoon, S. S., Hu, Y., Bhullar, B., Kelley, F., McCarron, S., Jepson, D. A., Shen, B., Taycher, E., Mohr, S. E., Zuo, D., Williamson, J., Mekalanos, J., LaBaer, J. (2008). Production and sequence validation of a complete full length ORF collection for the pathogenic bacterium Vibrio cholerae. Proc. Natl. Acad. Sci. USA 105: 4364-4369 [Abstract] [Full Text]  
• Labbate, M., Boucher, Y., Joss, M. J., Michael, C. A., Gillings, M. R., Stokes, H. W. (2007). Use of chromosomal integron arrays as a phylogenetic typing system for Vibrio cholerae pandemic strains. Microbiology 153: 1488-1498 [Abstract] [Full Text]  
• Wong, H.-c., Chen, S.-Y., Chen, M.-Y., Oliver, J. D., Hor, L.-I, Tsai, W.-C. (2004). Pulsed-Field Gel Electrophoresis Analysis of Vibrio vulnificus Strains Isolated from Taiwan and the United States. Appl. Environ. Microbiol. 70: 5153-5158 [Abstract] [Full Text]  
• Thompson, F. L., Iida, T., Swings, J. (2004). Biodiversity of Vibrios. Microbiol. Mol. Biol. Rev. 68: 403-431 [Abstract] [Full Text]  
• Thompson, F. L., Thompson, C. C., Vicente, A. C. P., Theophilo, G. N. D., Hofer, E., Swings, J. (2003). Genomic Diversity of Clinical and Environmental Vibrio cholerae Strains Isolated in Brazil between 1991 and 2001 as Revealed by Fluorescent Amplified Fragment Length Polymorphism Analysis. J. Clin. Microbiol. 41: 1946-1950 [Abstract] [Full Text]  
• Zo, Y.-G., Rivera, I. N. G., Russek-Cohen, E., Islam, M. S., Siddique, A. K., Yunus, M., Sack, R. B., Huq, A., Colwell, R. R. (2002). Genomic profiles of clinical and environmental isolates of Vibrio cholerae O1 in cholera-endemic areas of Bangladesh. Proc. Natl. Acad. Sci. USA 99: 12409-12414 [Abstract] [Full Text]  
• Hu, H., Lan, R., Reeves, P. R. (2002). Fluorescent Amplified Fragment Length Polymorphism Analysis of Salmonella enterica Serovar Typhimurium Reveals Phage-Type- Specific Markers and Potential for Microarray Typing. J. Clin. Microbiol. 40: 3406-3415 [Abstract] [Full Text]