This study examined 253 German cockroaches collected from 3 hospitals in Tripoli, Libya and 150 from the community. Bacteria was isolated from the cockroaches, including Klebsiella, Enterobacter, Serratia, Pseudomonas, and Streptococcus. More than 30% of the isolated Gram-negative bacteria were resistant to 3 or more antibiotics. Pseudomonas isolates showed the highest resistance rates, being more than 95% resistant to several common antibiotics. The study concludes that German cockroaches may play an important role in spreading antibiotic-resistant pathogenic bacteria in hospitals and the community.

1. Spread of Antibiotic-Resistant
Pathogenic Bacteria
in the Hospital and Community:
The Role of German Cockroach
R. Elgaderi1, K.S. Ghenghesh2 and
N. El-Berbash1.
Faculty of Science1 and
Faculty of Medicine2
Tripoli University, Tripoli-Libya.

2. OBJECTIVES
 To determine what are the pathogenic
bacteria carried by the German cockroach
found in hospitals and the community?
 To determine the resistance profiles of
isolated pathogenic bacteria to
antimicrobial agents.

3. The Culprit

4. METHODS
 Using standard bacteriological
procedures 253 German cockroaches
collected from 3 hospitals in Tripoli and
150 from the community were examined.
 Susceptibility to antibiotics was measured
by the disc diffusion method.

5. RESULTS
 Bacteria detected in hospital and
community cockroaches >> Table.

6. Bacteria isolated from hospital and
community cockroaches
No (%) positive
Organism
Hospital
Community
(n=253)
(n=150)
--------------------------------------------------------------------------------Escherichia coli
4 (1.6)
5 (3.4)
Klebsiella spp
33 (13.3)
70 (48.3)
Enterobacter spp
31 (12.4)
70 (48.3)
Citrobacter spp
18 ( 7.2)
22 (15.2)
Serratia spp
147 (59.0)
25 (17.2)
Proteus spp
3 (1.2)
2 (1.4)
Kluyvera spp
6 (2.4)
6 (4.1)
Buttiauxlla agrestis
1 (0.4)
1 (0.69)
Pseudomonas spp
28 (11.2)
11 (7.6)
Aeromonas spp
2 (0.8)
8 (5.5)
Gram-negative bacilli
12 (4.7)
0 (0.0)
Streptococcus spp
158 (63.5)
102 (70.3)

7. RESULTS
 Of the 439 Gram-negative organisms
isolated from hospital and community
cockroaches more than 30% were
resistant to 3 or more antibiotics.

8. Antimicrobial resistance of Gram-negative
bacilli isolated from hospital and
community cockroaches.
No (%) resistant from:
Antibiotic
Hospital
Community
Total
(n=193)
(n=246)
(n=439)
----------------------------------------------------------------------------------------Ampicillin
141 (73)
208 (85)
349 (80)
Amoxicillin86 (45)
88 (36)
174 (40)
clavulanic acid
Ceftazidime
28 (11)
53 (22)
81 (19)
Cephalothin
88 (46)
145 (59)
233 (53)
Chloramphenicol
51 (26)
39 (16)
90 (21)
Gentamicin
15 (8)
0 (0)
15 (3)
Nalidixic acid
36 (19)
19 (8)
55 (13)
Nitrofurantoin
89 (46)
53 (22)
142 (32)
Ciprofloxacin
0 (0)
1 (0.4)
1 (0.2)
Tetracycline
59 (31)
22 (9)
81 (19)
Trimethoprim48 (25)
16 (7)
64 (15)

9. RESULTS
 Pseudomonas isolates showed the
highest resistant rates being more than
95% resistant to ampicillin, amoxicillinclavulanic acid, cephalothin, chloramphenicol, nalidixic acid, tetracycline,
nitrofurantoin, trimethoprim-sulphamethoxazole and all (100%) were
susceptible to ciprofloxacin and
ceftazidime.

10. Resistance of Pseudomonas spp isolated
from hospital and community cockroaches
to antibiotics
No. (%) resistant
Antibiotic
Hospital
Community
Total
(n=34)
(n=9)
(n=43)
---------------------------------------------------------------------------------------Ampicillin
33 (97)
9 (100)
42 (97)
Amoxicillin33 (97)
9 (100)
43 (100)
clavulanic acid
Ceftazidime
0 (0.0)
0 (0.0)
0 (0.0)
Cephalothin
34 (100)
9 (100)
43 (100)
Chloramphenicol
33 (97)
9 (100)
42 (97)
Gentamicin
4 (12)
0 (0.0)
4 (9.5)
Nalidixic acid
34 (100)
9 (100)
43 (100)
Nitrofurantoin
34 (100)
9 (100)
43 (100)
Ciprofloxacin
0 (0.0)
0 (0.0)
0. (0.0)
Tetracycline
32 (94)
9 (100)
41(95.3)
Trimethoprim34 (100)
9 (100)
43 (100)

11. CONCLUSION
 The German cockroach may play an
important role in the spread of antibioticresistant pathogenic bacteria in the
hospital and community.