Abstract:
Isolates resistant to various antibiotics were
obtained from normal health human subjects in Birmingham
(U.K.) and Dar es Salaam (Tanzania). The level of
resistance observed was found to be quite high for both
Dar es Salaam and Birmingham. Twenty four (24) percent
or more of all isolates were resistant to 3 or more
antibiotics regardless of whether the isolates were
from Dar es Salaam or Birmingham.
An attempt was made to transfer these resistances
(assumed to be extrachromosQmal) to known recipients
B.coli K12S and E.coliK12N', Isolates from patients with
utLna'ry tract infections from Dar es SalaCl.jll were also
used in the transfer experiments as donors. The procedure
was repeated using 'un1rnown donors' and 'unknown recipients I
E.coliK12 W31l0 containing R-plasmid RPI was used
to monitor transfer efficiency. Transfer experiments were
performed at 2SoC or 370C and in ashaking or stationary
waterbath. This was in order to achieve the most efficient
transfer and control for potentially temperature sensitive
transfer mechanisms in donor strains.
There was a marked difference in the transfer ability
of R~factors between isolates from Birmingham. and those
from Dar es Salaam; the latter being higher. Transfer between
un1rnown donors and urllinown recipients was observed. However,
this was extremely low.
Transfer of drug resistance in Dar es Salaam isolates
was used to delineate the role of R-factors in the
.
increasing bacterial resistance to drugs used in the
treatment of urinary traet invections at the Muhimbili
Medical Centre.
