Background: Indiscriminate disposal of untreated wastes which are
often heavily laden with sewage microorganisms some of which are
pathogenic to humans into aquatic environments near cities could serve
as potential dangers to human health. Objective: A prospective study
was undertaken to investigate the scope of potential bacterial
pathogens and to assess the extent of pollution of the Douala lagoon.
Methods: A total of eighty water samples were collected fortnightly
from the lagoon at five stations from March to October 2005 and
analysed for heterotrophic bacterial densities, coliform counts, faecal
coliform and faecal streptococcal counts. Bacteria were isolated and
identified using standard microbiology and biochemical techniques.
Results: High heterotrophic bacterial counts (33 × 105 161
×105 CFU/ mL), total coliform counts (1.8 ×102 - 2.4
×102 CFU/ 100 mL), faecal coliform counts (2.2 × 102 2.4
× 102 CFU/ 100 mL) and faecal streptococcal counts (2.1 × 102
2.3 x 102 CFU/ 100 mL) were observed in all sampling stations. Eleven
species of bacteria: Bacteroides fragilis , Proteus vulgaris ,
Klebsiella pneumoniae , E. coli, Enterococcus faecalis , Enterobacter
aerogenes , Citrobacter freundii , Aeromonas hydrophila ,
Pseudomonas aeruginosa , Bacillus mycoides and Serratia marcesens ,
were frequently isolated. Conclusion: The presence of potential
bacterial agents such as Bacteroides fragilis, Pseudomonas aeruginosa,
Aeromonas hydrophila, Klebsiella pneumoniae and E. coli in the lagoon
may pose a serious threat to the health and well being of users of the
Lagoon and calls for urgent intervention