Isolation and Identification of Some Microbial Pathogens Associated with the External Body Surface of Periplaneta americana in Umuahia, Abia State

Aim:  This  study  was  carried  out  to  isolate  and  identify  the  microbial  pathogens  of  medical importance  on  the  external  body  surfaces  of  Periplaneta  americana  collected  from  toilet  areas, residential/hostel  areas  and  health  facilities  in  Umuahia  metropolis,  Abia  State,  south-eastern Nigeria.  
Study Design: Cross sectional study. 
Place  and  Duration  of  Study:  The  study  was  carried  out  in  Umuahia  metropolis,  Abia  State, south-eastern Nigeria between October-December, 2014. 
Methodology: A total of 100 cockroaches from toilets (30), residential/hostel areas (46) and health facilities (24) in Umuahia were collected and their external body parts screened for bacterial, fungal and  parasitological  carriage.  Sterile  physiological  saline  used  as  washing  fluid  of  the  external surface  of  each  cockroach  was  cultured  by  the  streak  plate  method.  The  isolated bacteria  were identified using standard bacteriological methods. Antibiotics susceptibility tests were done by the disc diffusion method. 
Results: Results showed that all the cockroaches were positive for different species of medically important bacteria and fungi.  Escherichia coli were the most common bacteria in the cockroaches’ from toilet (21.14%) and residential/hostel areas (22.37%) while, Staphylococcus aureus (21.74%) was the most frequent isolate obtained from cockroaches obtained from health facilities. Aspergillus species  (33.16%)  was  the  most  prevalent  fungal  group.  Quantitative  analysis  of  the  total  viable count and microbial loads of the bacterial and fungal isolates from the three sites revealed that the isolates obtained from toilet areas were high as compared to those from residential areas.  Antibiotic  susceptibility  of  all  the  bacteria  isolates  revealed  a  common  pattern  of  multiple  drug resistance  amongst  isolates  from  health  facilities  when  compared  to  those  from  toilet  and residential areas. 
Conclusion:  The  result  indicated  that  Periplaneta  americana  is  a  possible  reservoir  of  several pathogens via their bodies and thus may spread multiple drug resistant species.  
Keywords: Microbial pathogens; external surface; Periplaneta americana