Study area, design and period
A hospital-based cross-sectional study was conducted from October 2016 to June 2017at Ayder Specialized Comprehensive Hospital, Mekelle, Northern Ethiopia. Mekelle city is situated783 km North of Addis Ababa, the capital of Ethiopia. It is the largest hospital serving for more than 4.1 million people of the region and the neighboring regions. The hospital has adult, neonatal, and pediatric ICU health services.
All non-critical medical equipment and inanimate surfaces that had frequent contact with patients and/or healthcare providers during the study period were included. A total of 130 swabs from medical equipment and inanimate surfaces (55 swabs from Adult, 44 swabs from pediatric and 31 swabs from neonatal) were collected using purposive sampling technique.
Sample collection, handling, and transport
Sterile cotton-tipped applicator sticks, moistened with sterile normal saline, was used to collect swab specimen. Swab samples were taken using aseptic techniques with the presence of a spirit lamp. All swab samples were inserted in a separate sterile test tube, labeled and transported to the Medical Microbiology and Immunology Laboratory, Mekelle University, using icebox within 1 hour and processed immediately .
Bacterial culture and identification
Swabs were inoculated on to Blood agar, MacConkey agar and Mannitol salt agar (Oxoid Ltd, UK). The inoculated plates were incubated at 37°C for 24 hours. The inoculated plates were inspected after 24 hrs of incubation and bacterial isolates from culture-positive plates were identified at the species level by their colony morphology, gram-staining and biochemical characteristics (catalase, coagulase, urease, indole, oxidase, citrate utilization, glucose and lactose fermentation, gas and hydrogen sulfide production) .
Antimicrobial susceptibility testing
Antimicrobial susceptibility testing was performed using modified Kirby-Bauer disk diffusion according to the Clinical and Laboratory Standards Institute (CLSI), guideline .Bacterial isolates were tested for commonly used antibiotics including: amoxicillin-clavulanic acid (AMC, 30mcg), ampicillin (AMP, 10mcg), ceftriaxone (CTR, 30mcg), ciprofloxacin (CIP, 5mcg), chloramphenicol (C, 30mcg), gentamicin (GEN, 10mcg) and tetracycline (TE, 30mcg), cefoxitin (CX, 30mcg), erythromycin (E, 15mcg), penicillin G (P, 10units), amikacin (AK, 30mcg), cefotaxime (CTX, 30mcg), nalidixic acid (NA, 30mcg) (HIMEDIA, Company).
Data were entered into Microsoft Excel. Data were imported and analyzed using Statistical Package for Social Sciences (SPSS) software version 21.0. Descriptive statistics were computed and results were summarized by using tables.
Aseptic techniques were used in all the steps of specimen collection and inoculation to minimize contamination. Specimens were collected in the presence of sprit lamp to prevent bacterial contamination from air. Reagents and antimicrobial discs were checked for expiry date. Sterility of culture media was carried out by incubating 5% of the prepared media prior to inoculation. Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853) reference strains were used to control the performance of culture media and antibiotic discs. All results were checked accuracy and cleaned after entering to SPSS.
Non-critical medical equipment: is equipment used for the diagnosis and management of the patient in ICU such as Sphygmomanometer, stethoscope, and thermometer.
The inanimate surface is a surface of the material used in ICU during providing patient care such as bedside tables, mattress, computers, and computer standing tables.