The effect of pollution on
Vibrio
spp. in five sampling stations along Woji River in Port
Harcourt was studied in the months of April and November 2010.
Vibrio vulnificus
,
V. parahaemolyticus
and
Vibrio
alginolyticus
were isolated. The Plate count technique on Thiosulphate Citrate Bile Salt agar revealed a high
population density of vibrios in the sampling stations than the Most Probable Number (MPN) technique. The
average population density of vibrios ranged from 21MPN/100ml at Oginigba (station 1) to 1100MPN/100ml at
Trans Amadi by slaughter (station 3) in April and 43MPN/100ml to 1100MPN/100ml in November respectively
compared to plate counts that ranged from 2.2 x 10
5cfu/100ml to 1.6 x 10
8cfu/100ml in April and 3.2 x
10
5cfu/100ml to 2.6 x 10
8cfu/100ml in November respectively. The percentage proportion of
Vibrio
spp. to
other heterotrophic bacteria ranged from 0.01 to 5.44% in April and 0.03 to 9.96% in November. The
concentration of Total Dissolved Solids (TDS), Calcium, Magnesium, Hardness and chloride were much higher
than the DPR/WHO limits and were not related to increase in presence of vibrios or their relative densities
except for total dissolved solids. However, heterotrophic counts were high irrespective of the sampling station.
There is therefore an urgent need to curtail the continued negative anthropogenic activities along the river
course.
