Volume 15, Number 1—January 2009
Letter
Classical ctxB in Vibrio cholerae O1, Kolkata, India
Amit Raychoudhuri, Tapas Patra, Kausik Ghosh, Thandavarayan Ramamurthy, Ranjan K. Nandy, Yoshifumi Takeda, G. Balakrish Nair, and Asish K. Mukhopadhyay
Table
Prevalence of different types of ctxB alleles among Vibrio cholerae O1 strains, Kolkata, India, 1989–2005
| Year isolated | No. strains tested | No. alleles |
||
|---|---|---|---|---|
| Classical ctxB | El Tor ctxB | Classical + El Tor ctxB | ||
| 1989 | 6 | 0 | 6 | 0 |
| 1990 | 7 | 4 | 3 | 0 |
| 1991 | 10 | 8 | 0 | 2* |
| 1992 | 10 | 4 | 5 | 1* |
| 1993 | 6 | 4 | 2 | 0 |
| 1994 | 9 | 8 | 1 | 0 |
| 1995 | 23 | 23 | 0 | 0 |
| 1996 | 10 | 10 | 0 | 0 |
| 1997 | 10 | 10 | 0 | 0 |
| 1998 | 10 | 10 | 0 | 0 |
| 1999 | 10 | 10 | 0 | 0 |
| 2000 | 10 | 10 | 0 | 0 |
| 2001 | 10 | 10 | 0 | 0 |
| 2002 | 10 | 10 | 0 | 0 |
| 2003 | 10 | 10 | 0 | 0 |
| 2004 | 10 | 10 | 0 | 0 |
| 2005 | 10 | 10 | 0 | 0 |
*These strains carry the ctxB gene for El Tor as well as classical strains.
