TABLE 4.
Distribution of virulence genes among isolates of V. cholerae, V. parahaemolyticus, and V. vulnificus
| Origin | Sampling season | No. (%) of positive strainsa |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
V. cholerae (n = 24) |
V. parahaemolyticus (n = 1,757) |
V. vulnificus (n = 130) |
||||||||
| ctxA | rfb O1 | rfb O139 | tcpA El Tor | tcpA classical | tdh | trh | tdh + trh | vvp | ||
| Tidal water | June 2013 | 0 | 0 | 0 | 0 | 0 | 0 | 6 (6.5) | 0 | 30 (88.2) |
| September 2013 | 0 | 0 | 0 | 0 | 0 | 13 (6.1) | 34 (15.9) | 12 (5.6) | 5 (100.0) | |
| December 2013 | 0 | 0 | 0 | 0 | 0 | 0 | 1 (0.7) | 0 | 0 | |
| February 2014 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| April 2014 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
| Mud | June 2013 | 0 | 0 | 0 | 0 | 0 | 0 | 23 (8.2) | 0 | 88 (96.7) |
| September 2013 | 0 | 0 | 0 | 0 | 0 | 1 (0.3) | 2 (0.5) | 0 | 0 | |
| December 2013 | 0 | 0 | 0 | 0 | 0 | 0 | 3 (1.6) | 0 | 0 | |
| February 2014 | 0 | 0 | 0 | 0 | 0 | 3 (1.7) | 0 | 0 | 0 | |
| April 2014 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | |
a
Presence of genes as determined by PCR. Genes: ctxA, cholera toxin (CT); rfb O1, serotype O1-specific rfb region; rfb O139, serotype O139-specific rfb region; tcpA El Tor, El Tor toxin-coregulated pilus (TCP); tcpA classical, classical TCP; tdh, thermostable direct hemolysin (TDH); trh, TDH-related hemolysin; vvp, elastolytic protease.