This is the first study in Malawi to determine the extent of surgical site infections (SSIs) and antimicrobial use following cesarean section at QECH in Blantyre. The overall incidence of SSI during the study period was 10% (20 of 208 patients). Most patients were given antibiotics either prophylactically or post-CS without performing culture to ascertain AMR. Similarly, this finding is consistent with findings in Vietnam (10.9%) [24]. Of course, Borgstein's prospective survey findings at QECH in Blantyre revealed a 25.8% overall infection rate in general surgeries [12]. Similarly, other studies reported incidences of 21% in Ethiopia [6] and 7-9.6% in Nigeria [5, 7]. The incidence of SSIs in this study was greater than that in developed nations [25, 26]. Additionally, health care in Africa is less accessible and of poor quality than that in developed nations [16].
In the present study, among the etiological agents isolated, 3 (60%) were gram-positive cocci (clusters). Staphylococcus aureus was the most common organism. This finding is in line with previous findings that Staphylococcus aureus is the most common cause of SSIs following post-CS [27, 28]. Similarly, other studies have shown that Staphylococcus aureus is a commonly isolated cause of SSI, accounting for 20–30% of SSIs occurring in hospitals [6, 14, 29]. Furthermore, other isolates identified in our study included Enterobacteriaceae and Acinetobacter baumannii. In the present study, the Staphylococcus aureus isolates were resistant to most antibiotics, such as clindamycin, erythromycin, gentamicin and cefoxitin, similar to the findings of Fantahamu et al. [30]. Furthermore, Enterobacteriaceae were sensitive to ciprofloxacin, meropenem, amikacin and tigecycline, and the same bacteria were resistant to chloramphenicol and trimethoprim-sulfamethoxazole. However, Acinebacter Baumanni was sensitive to gentamicin and resistant to ceftriaxone, ciprofloxacin, cefotaxime and Tigecycline, as also reported in other studies [30, 31].
This study also revealed that 138 (66.35%) patients received both preop antibiotics (ceftriaxone) and post-CS antibiotics. The most common post-CS-prescribed antibiotics were metronidazole and ceftriaxone combined therapy, even for patients with noncomplicated CS. A study by Lamont et al. indicated that a single dose of antibiotics could be as effective as multiple doses given perioperatively [32]. No patient had a known infection or specific bacterial organism isolated in the current study at the time these antibiotics were prescribed and administered; hence, this may also promote antimicrobial resistance spread due to unnecessary use of antibiotics in our hospitals.
In contrast to previous studies, skin closure, BMI, HIV status, education level, age, duration of CS, membrane status pre-CS, parity, ANC visits and gestational age were not significant risk factors in our study sample [26, 30, 33, 34]. Additionally, Kaye et al. reported that age was a powerful predictor of SSI [35]. However, other studies have also reported contamination or dirt operation as a risk factor [26] and wound classification as clean contamination for the CS procedure [19].
The present study revealed that all the women who underwent CS were given antibiotic prophylaxis with ceftriaxone. The average duration from the first dose of antibiotic prophylaxis to the start of the CS procedure was 12.85 minutes, with a standard deviation of 8.44 (IQR = 8). The prevalence of SSI and the timing of antibiotic prophylaxis in clinical practice have not been thoroughly investigated, but some clinical trials have indicated a relationship [18]. In the same study by Classen et al. [18], few patients developed SSI among those who received antibiotic prophylaxis early before the start of surgery compared to those who received antibiotics later after surgery. Furthermore, in the present study, three patients who received post-CS antibiotic prophylaxis and two patients who did not receive antibiotics after surgery had antimicrobial resistance. Of course, these patients without any confirmed infection diagnosis received antimicrobial treatment after caesarean section; hence, this therapy cannot be applied as an indicator of SSI. The inappropriate use of antimicrobial agents needlessly exposes patients to potential toxicity and risks that promote the development and spread of antimicrobial resistance, leading to increased medical care costs in healthcare facilities [26]. However, the rational use of antimicrobials in women of child-bearing age is important because it affects this population as well as their offspring. [15].
The strengths and limitations of the study
The strengths of the study include that the study revealed the emergence of AMR in the Malawian setting and that the study used primary data for SSIs following CS. However, the study was limited to SSIs following CS, and the number of HAIs occurring in other settings, such as surgical departments or wards for various hospitals for general surgery, cannot be estimated. Some patients who developed SSIs did not return to the hospital again for review, which could lead to a lack of microbiological data related to SSIs. Last, the small sample size could have affected the outcomes of interest.