6 research outputs found
Prevalence, species differentiation, haemolytic activity, and antibiotic susceptibility of aeromonads in untreated well water
The use of untreated water for drinking and other activities have been associated with intestinal and extraintestinal infections in humans due to Aeromonas species. In the present study aeromonads were isolated from 48.7% of 1,000 water samples obtained from wells and other miscellaneous sources. Aeromonas species were detected in 45% of samples tested in spring, 34.5% in summer, 48% in autumn and 60% of samples tested in winter. Speciation of 382 strains resulted in 225 (59%) being A. hydrophila, 103 (27%) A. caviae, 42 (11%) A. sobria and 11 (3%) atypical aeromonads. Of 171 Aeromonas strains tested for their haemolytic activity, 53%, 49%, 40% and 37% were positive in this assay using human, horse, sheep and camel erythrocytes respectively. The results obtained indicate that potentially enteropathogenic Aeromonas species are commonly present in untreated drinking water obtained from wells in Libya (this may also apply to other neighbouring countries) which may pose a health problem to users of such water supplies. In addition, ceftriaxone and ciprofloxacin are suitable drugs that can be used in the treatment of Aeromonas-associated infections, particularly, in the immunocompromised, resulting from contact with untreated sources of water
Serotypes, virulence factors, antibiotic sensitivity, beta-lactamase activity and plasmid analysis of Salmonella from children with diarrhea in Tripoli (Libya)
A total of 21
Salmonella
strains isolated
in Libya (16 from children with
diarrhea
and 5 from healthy
controls) were serotyped and studied
for their cell invasive
ability,
production
of cytotoxin,
antibiotic
susceptibility,
β-lactamase activity and plasmid profiles.
Eight different serotypes of
Salmonella
were identified:
6
S. saintpaul
,
4
S. wien
(1 from
control), 2
S. newport
, 2
S. muenchen
(1 from contr
ol), 2
S. typhimurium
(1 from control)
, 2
S. hadar
(1 from control), 2
S. reading
(1 from control), 1
S. kottbus
. Twenty (95%) were
positive
in the invasiveness
assay using
HeLa cells,
and all (100%) were negative
for
cytotoxin
production
in HT29 cells. More than 40%
were resistant to ampicillin, cefalexin,
cefam
andole,
cefoperazone,
chloramphenicol,
gentamicin, mezlocillin and trimethoprim-
sulphamethoxazole and 100%
were susceptible
to the new quinolones. Most (67%)
of the
strains harbored plasmids and 43%
produced
β-lactamase. A strong association was
observed between
the presence
of more than one plasmid,
β-lactamase activity, and
multiple-resistance to antimicrobial agents
and serotypes
S. saintpa
ul
and
S. wien
. Curing
experiments with acridine
orange
showed
that 2 plasmids (33 and 1.4 megadaltons
) might
be responsible
for the resistance to chloramphenicol
and gentamicin. The present study
demonstrated that multiple-resistant salmonellae are widesp
read in Libya and the resistance
is mainly
plasmid mediated
Enteric Pathogens Associated with Childhood Diarrhea in Tripoli-Libya
Stool samples from children < 5 years of age with diarrhea (N = 239) were examined for enteric pathogens using a combination of culture, enzyme-immunoassay, and polymerase chain reaction methods. Pathogens were detected in 122 (51%) stool samples; single pathogens were detected in 37.2% and co-pathogens in 13.8% of samples. Norovirus, rotavirus, and diarrheagenic Escherichia coli (DEC) were the most frequently detected pathogens (15.5%, 13.4%, and 11.2%, respectively); Salmonella, adenovirus, and Aeromonas were detected less frequently (7.9%, 7.1%, and 4.2%). The most commonly detected DEC was enteroaggregative E. coli (5.4%). Resistance to ≥ 3 antimicrobials was observed in 60% (18/30) of the bacterial pathogens. Salmonella resistance to ciprofloxacin (63.1%) has become a concern. Enteric viral pathogens were the most significant causative agents of childhood diarrhea in Tripoli. Bacterial pathogens were also important contributors to pediatric diarrhea. The emergence of ciprofloxacin-resistant Salmonella represents a serious health problem that must be addressed by Libyan health authoritie