Abstract:

Background: Surgical site infections (SSIs) are among the leading healthcare associated infections (HCHAIs) mostly acquired endogenously (from patient’s own flora) during or soon surgical procedures. The efficacy of preoperative skin preparation antiseptics plays the major role in ensuring clean surgeries, although this had limited knowledge at our setting, Mwanza-Tanzania. This study determined the efficacy of antiseptics for preoperative skin preparations against multidrug resistant (MDR) and biofilm forming gram-negative bacteria (GNB) at Bugando medical centre (BMC) in Mwanza, Tanzania.

Methods: This cross-sectional laboratory-based study was conducted between June and September 2020. Extended spectrum beta-lactamase (ESBL) producing GNB (K. pneumoniae, n=13 and E. coli, n=13) with/without biofilm formation archived in -80’C were recovered by sub culturing on MacConkey agar (MCA) plates and then incubated at 37’C for 24 hours. Purposive contamination of sterile polystyrene surfaces were done following disinfection with surgical antiseptics methylated spirit (70%MS) and Povidone iodine (10%PVI) and then sterile cotton swabs were used to swab these surfaces after air dry and ten minutes exposure. Swab samples were then inoculated on plain MCA plates and incubated at 37’C for 24 hours. Data analysis were done by using STATA version 13.0 software.

Results/Discussion: Overall 7.7% (2/26) of isolates where resistant to antiseptics used at OT’s rooms, in which all resistance occurs to 70%MS and there was no resistant to 10%PVI. One isolate resisted in 1 turbidity of bacteria suspension in both after air dry and after ten minutes exposure and the other isolate resisted in both 0.5 and 1 turbidity of bacteria suspension after air dry only. The magnitude of resistant was high after air dry compared to after ten minutes exposure, this signify that time of exposure was paramount in efficacy of antiseptics.

Conclusion: This study found that, 10%PVI was effective against MDR and biofilm forming GNB, while 70%MS has resistant of 7.7% (2/26) against MDR and biofilm forming GNB.