Abstract
Background
The transmission of waterborne, foodborne, and airborne infections following flooding is common around the world. There is a need to study and understand the bacterial biodiversity of flood water during massive floods.
Objectives
To determine the 16S rRNA bacterial biodiversity of flood water that affected parts of Kota Bharu, Kelantan, Malaysia from December 2014 to January 2015.
Methods
We collected 31 water samples in 50 mL sterile containers from 6 different locations. Bacteria were cultured by inoculating into blood and nutrient agar using sterile swabs. Various bacteria were identified from the cultures that grew within 24-48 h, using colony morphology, differential/selective media, and biochemical tests. The isolated bacteria were identified using DNA Sanger sequencing and comparing with sequences at NCBI BLAST and SepsiTest BLAST up to species level, and sequences were deposited at GenBank. A 16S rRNA biodiversity chart was obtained. Sequences with low trace score (< 20) were removed, sequences were trimmed, capped (pair-wise assembled) and the 16S biodiversity was analyzed using a 16S biodiversity tool (Geneious version R8.1).
Results
The 16S biodiversity tool results revealed 22 genera of bacteria belonging to 12 families: Moraxellaceae (10%), Aeromonadaceae (8%), Comamonadaceae (13%), Neisseriaceae (2%), Bacillaceae 1 (16%), Staphylococcaceae (8%), Bacillales Incertae Sedis XII (3%), Bacillaceae 2 (3%), Streptococcaceae (2%), Flavobacteriaceae (2%), Enterobacteriaceae (25%), and Pseudomonadaceae (10%). Antibiotic susceptibility tests revealed Klebsiella pneumoniae of the family Enterobacteriaceae as the most resistant (71.4%) to all 7 antibiotics tested.
Conclusions
The isolation of some relatively new species of bacteria in the floodwater in Malaysia needs to be taken into consideration for epidemiological study of flood pathogens to determine future public health implications. Antibiotic resistance of bacteria should support choice of therapy.