Microbiological surveys conducted by the U.S. Environmental Protection Agency (USEPA) of finished drinking water utilities from
four states, during 2000 / 2001, yielded 205 Aeromonas isolates. A Polymerase Chain based
(PCR) based genetic characterization of these isolates determined the presence of six virulence
factor genes: elastase (ahyB), lipase (pla), the flagella A and B genes (fla) and three enterotoxins
(alt, act and ast). Primer sets were designed for all the target genes, except for act, which had
been published previously. PCR was performed in three duplex assays using the following
primer sets together: elastase (ahyB) and lipase (pla); fla and alt ; act and ast. pla was present
in 86%, act in 69%, fla in 55%, ahyB in 40% and alt and ast in 45% and 30% of the strains,
respectively. Only one isolate had all six virulence genes. Multiple species were isolated from
most of the utilities and different combinations of virulence factors were observed, sometimes
even in different strains of the same species. However, a dominant strain having the same set of
virulence factors, was usually isolated from different rounds of sampling from a single tap.
These results suggest the importance of examining as many Aeromonas isolates as possible from
a water sample. The results indicate Aeromonas strains isolated from water utilities have the
potential to be pathogenic, although additional hitherto uncharacterized virulence factors may be
needed to cause actual disease. Includes 34 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 2.2 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 11/02/2003 |
