The emergence of multi-drug resistant (MDR) strains in healthcare facilities poses a threat to the management of infections in developing countries [1]. Approximately 700,000 people die annually from antimicrobial-resistant (AMR) infections globally [2], with a projected 10 million deaths by 2050 [3]. In Kenya, high levels of hospital-acquired infections (HAIs) have been reported signifying the need for reinforced infection prevention control strategies [4–6]. Multidrug-resistant bacterial contaminants have been reported in hospital wards in Kenya [7] albeit in a small number of hospitals.

At present, β-lactam drugs are a key factor in the treatment of bacterial infections worldwide and account for almost 65% of antibiotic usage [1]. These drugs have been classified into six main groups based on the chemical structure of the β-lactam ring, including penicillins, cephalosporins, cephamycins, carbapenems, monobactams, and β-lactamase inhibitors. Unfortunately, despite their crucial role in combating infections, recent years have witnessed a concerning global rise in resistance to this important class of antibiotics [8].

Both community-acquired infections (CAIs) and HAIs causative agents have seen a considerable increase in antimicrobial resistance [9]. The hospital environment, in particular, serves as a source of multidrug-resistant organisms (MDROs), especially when routine practices such as environmental disinfection, contact precautions, and hand hygiene are not consistently implemented [10]. Pathogens reported to persist in these healthcare environments include Clostridium difficile spores, vancomycin-resistant Enterococcus (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and Acinetobacter baumannii [11]. High-risk areas for contamination include hard surfaces like beds, handles, and grab bars. Transmission of pathogens to patients is thought to be through healthcare workers, visitors, or asymptomatic carriers [12]. Although enhanced cleaning of hospital surfaces has been advocated to overcome the transmission of MDROs, a study conducted in 2008 examined the cleaning of hospital surfaces in 36 acute care hospitals in the USA and found that only 47% of these surfaces were effectively cleaned [13]. This represents a critical area that needs attention in the fight against the spread of MDROs.

In case of CAI, resistance can be attributable to the widespread use of broad-spectrum antibiotics, over the counter sale of antibiotics, self-administration of antibiotics, inappropriate use of antibiotics, and a lack of compliance with treatment [14, 15]. Conversely, in the case of HAIs, causative agent antimicrobial resistance is mainly due to the extensive use of broad-spectrum antibiotics in their management. Among the microorganisms usually implicated in HAIs include Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Klebsiella species, and coagulase-negative Staphylococci. Some of the factors that contribute to the development of HAIs includes hospital design factors (e.g., ventilation and an adequate number of handwash basins) [16], longer hospital stays, gender, surgery since admission, intubation, mechanical ventilation, age of the patient, type of hospital, and urinary catheter and hygienic practices [17].

In Kenya, the past decade has seen a significant increase in efforts to describe and address the burden of drug-resistant infections in the country. These efforts have increasingly focused on hospitals like the Thika Level V Hospital in Thika. By participating in these initiatives, Kenya aims to eventually contribute AMR related data to global platforms such as the World Health Organization’s Global Antimicrobial Resistance Surveillance System (GLASS) [18]. Thus, this study aimed to determine bacterial contaminants and their antimicrobial susceptibility patterns from medical equipment, and inanimate surfaces at the Thika Level V Hospital. The study further determined the antibiotic resistance profile for each clinically important isolate. We observed high levels of resistance to key antimicrobials, especially by enteric bacteria.

Bacterial infections contribute to patients’ poor prognosis and increased risk of ICU admission and mortality [4]. The present study reveals a high culture positivity which was higher than that reported in Rwanda [19] and South Ethiopia [21]. Among the positive samples, those associated with females were less than those from males contrary to other studies which demonstrated more samples from females than males. This was mainly due to the sharp increase in motorcycle accidents in Kenya, which mainly affects males [22]. Gram-negative bacteria were the more dominant isolates similar to other studies conducted in Africa [21, 23]. Overall, coagulase-negative Staphylococci were the most isolated bacterial isolates, comparable to other studies that indicate CONS as the most commonly isolated microorganisms in clinical settings [24].

The bacterial spectrum was typical to other studies in Eastern Africa [25–29] but here we describe the S. maltophilia and B. cepacia for the first time in our study site from pus and urine samples in both medical and surgical wards. S. maltophilia is a multidrug Gram-negative bacillus that is an opportunistic pathogen, particularly for hospitalized patients [30] while B. cepacia is resistant to multiple antimicrobials and its treatment poses a challenge [31].

In the present study, most of the positive samples from the environment were from the ICU and constituted S. aureus. Similar results have been reported in Ethiopia [32]. The low number of positives in the renal unit may be attributable to frequent fumigation that is done at the renal unit, specifically after the dialysis sessions and effective infection prevention control mechanisms. These findings are echoed by other studies, which have reported no growth from dialysis ward bacterial surface culture in Northwest Ethiopia [33].

Among the different surfaces and inanimate objects examined, the highest bacterial contaminated samples were taken from bed rails, cabinets, and monitors, corroborating the findings from similar studies in Iran and Nigeria that identified beds as highly contaminated [34–36]. Overall, CONS were the most frequently isolated bacteria followed by S. aureus, consistent with findings from different studies from Ethiopia and elsewhere [35, 37]. As for P. luteola, it made up 9.5% of the isolates. The rate of isolation is comparable to other similar studies [38]. Trauma patient samples yielded the largest number of bacterial isolates (33.1%) since most of them had undergone orthopaedics surgery and were in the surgical ward. This finding is similar to a previous study that recorded high rates of bacterial infection in orthopaedics patients at a Tertiary Care Hospital in Bengaluru [39].

In this study, A. baumannii was highest in number amongst isolates from the surgical ward. Other studies have demonstrated that this species is frequently associated with skin and tissue infections at surgical sites [40, 41]. Infections due to S. aureus were also high among all medical ward isolates.

In the present study, the sampling points for urine samples were ICU, surgical, and medical wards, which have long-term admissions and catheterization. It has been reported that catheterization increases the incidence of urinary tract infection (UTI) by 3–5% and long admission increases the probability of acquiring UTI since hospitals are one of the sources of infection [42]. Renal unit patients were revealed to be associated with the highest positive bacterial cultures of urine samples (50%) compared to all other clinical samples. This finding confirms that individuals with dysfunctional kidneys are more prone to urinary tract infections as previously reported by a study in Saudi Arabia [37].

Resistance to antimicrobial agents is a problem in healthcare facilities, but in hospitals, transmission of bacteria is amplified because of the highly susceptible population [43]. The observed high resistance rates suggest poor adherence to antibiotic use guidelines and infection prevention policies in our study setting and beyond [44, 45]. The antibiotic sensitivity test results of our study confirmed that an alarming percentage of resistance was exhibited by bacterial isolates to the commonly prescribed antibiotics. Among the ESBL producers, the highest rates were observed amongst E. coli (32.6%) similar to other studies [46–48] and they were followed by E. cloacae isolates (18.6%). It has been reported that E. cloacae have a selective advantage over other bacteria to produce Amp C when there is antibiotic pressure [49]. The E. cloacae in this study demonstrated 100% resistance to cefotaxime and cefoxitin. Resistance to cephalosporins is mostly pronounced in these species [42]. Enterobacteria from this study remained highly resistant to cefuroxime, cefotaxime, piperacillin, and cefoxitin in general similar to a previous study in Dakar [50]. On the other hand, meropenem, imipenem, levofloxacin, and minocycline remained highly effective amongst the enteric bacteria. ESBL prevalence of 65.9% in our study is comparable to a similar study in Kenya amongst severely ill COVID-19 patients of 67.3% [51]. However, this rate is higher than a rate reported in Tanzania (33.14%) [52] and lower than that of Uganda (89%) [53]. African countries with high rates of ESBL producers according to Onduru et al. were Democratic Republic of Congo (92%), Tanzania (89%) and Malawi at 62% [54].

K. pneumoniae isolates in this study were also highly resistant to cephalosporins but susceptible to minocycline, meropenem, and imipenem. This pattern was also noted for P. mirabilis isolates. E. coli isolates highest resistance rates were against cefotaxime and piperacillin. Resistance rates for sulphamethoxazole were at 71% while that of ceftazidime and aztreonam were at 67%. The effective drugs against E. coli were amikacin and carbapenems. This is consistent with a similar study carried out elsewhere (39). A. baumannii, B. cepacia, and S. maltophilia isolates were highly resistant to all groups of drugs and this is consistent with findings from other studies in Kenya and beyond [55, 56].

The overall prevalence of MRSA was 59% (19/32). Recent studies indicate that disc diffusion test using cefoxitin is far superior to most of the currently recommended phenotypic methods like oxacillin disc diffusion. It has been reported as surrogate marker of mecA gene, gives clearer end points, easier to read and is more reproducible than tests with oxacillin disk diffusion. Thus, cefoxitin is now an accepted method for detecting MRSA with high efficiency and has been used as an alternative to PCR in resource constrained areas. This MRSA prevalence is higher compared to 22.6% from a similar study in Nigeria [57]. In Kenya, the prevalence of MRSA from previous studies was found to range from 1–84% [58]. One key limitation of this study is the absence of anaerobic cultures to identify anaerobic bacteria responsible for hospital-associated infections. Thus, it is important to highlight the need for future research to include anaerobic culture methods to adequately identify and understand the impact of these bacteria in hospital settings.

This study recorded the presence of multidrug-resistant organisms of concern including recently emerged ones such as S. maltophilia and B. cepacia at Thika Level V Hospital. The implications of these organisms on patient outcomes and the potential for outbreaks are significant, necessitating the adoption of robust strategies to limit their spread. Encouraging judicious use of antimicrobial agents, implementing effective waste-handling protocols, and regular cleaning of high-touch surfaces, are critical steps towards reducing bacterial loads and preventing hospital-acquired infections. In addition, periodic monitoring systems should be implemented to enable prompt detection and management of infections. This study underscores the urgent need for continued efforts to mitigate the emergence and transmission of multidrug-resistant organisms in hospitals.