This study revealed that medical students have poor knowledge about the use of antibiotics to the extent that the ratios were between 44.2 ± 9.9 and 63.1 ± 19.4 points. In general, students perceive that training received from the university regarding the topic is insufficient. In this regard, it is important to remember that the World Health Organization has highlighted the importance of improving the training of undergraduate students in the use of antibiotics as one of the main strategies to preserve their effectiveness [910]. Despite this, the results of this research, plus that reported for students from the United States [11], Spain [12] and seven other European countries [13] reflect that education on this topic is still deficient.
The interpretation of antibiograms is highlight among the topics in which the students consider that they receive insufficient training by the university, standing out with 43.5%. This finding is similar to an investigation in Chinese students where the frequency of dissatisfaction with the education received to interpret antibiograms was 71.7% [14]. The interpretation of antibiograms is a fundamental competence for trainee doctors because it guides the detection of new mechanisms of resistance, the knowledge of epidemiology in a defined geographical area and the choice of antimicrobial treatment. However, the interpreted reading of an antibiogram is a complex exercise that involves knowing, for instance, that there are antibiotics that are only slightly affected by the resistance mechanisms, so that they are reported as sensitive in inhibitory tests in cases when they are resistant. A classic example is the false sensitivity of Salmonella spp to ciprofloxacin and levofloxacin if these isolates are resistant to nalidixic acid. In the same vein, the false sensitivity to amikacin and tobramycin in S. aureus when it is resistant to gentamicin [15]. Failure to recognise these particularities has consequences in the choice of therapy - it leads to therapeutic failure, omits the reporting of new resistance mechanisms and increases costs by requiring specialised diagnostic tests. Therefore, teaching in this field constitutes a challenge for the city medical schools. Nevertheless, it’s necessary to complement these actions by encourage their mission as promoters of health education, especially so that patients follow medical recommendations and adhere to therapies
Regarding knowledge about the treatment of specific infections, it was found to be low for respiratory infections due to a tendency toward the indiscriminate use of azithromycin, the selection of otitis treatment in children and the use of antibiotics in cases of acute pneumonias. This finding coincides with previous studies in practising physicians which found that 45% [16] to 64.2% of antibiotic prescriptions for patients seen for respiratory tract infections are inadequate [17]. Specifically, in medical students it has been shown that 18.1% consider that antibiotics are useful for the treatment of viral respiratory infections [18]. These findings evidence that it is necessary to improve the knowledge of the treatment of respiratory infections in trainee physicians because these infections are among the ten main causes of morbidity and mortality in the general population. They are within the first three in the paediatric population [19], and cases of pneumonia are the leading cause of death due to infectious diseases [20]. Not improving said knowledge has two implications. On the one hand, the prescription of antibiotics for cases in which they are not indicated contributes to the selection pressure for resistant microorganisms. On the other, adequate treatment is delayed, contributing to morbidity and mortality due to this cause.
With regards to UTIs, it was found that the average for this ratio was 58.7 ± 14.8 with a high proportion of students stating that all asymptomatic urinary infections in diabetic women must be treated and that the first choice of treating a UTI must be Ampicillin/Sulbactam. This finding coincides with another investigation carried out in which 47.3% of students do not identify the appropriate UTI therapy [14]. In addition to mistakes regarding the correct therapy, research carried out on practising physicians found that only 41% of antibiotic prescriptions for these types of infections are written according to recommended dosing, intervals and duration [21]. It has been described that in up to 96% of cases antibiotics are prescribed for UTIs in pregnant women without them being indicated [22]. Errors in the prescription of antibiotics for these types of infections is an important topic given that UTIs are one of the most common causes of doctor visits at the primary care level, affecting nearly 150 million people per year worldwide [23]. In the USA these cases are to blame for 0.7% of all outpatient visits. It is estimated that 7 million women per year seek medical care due to UTIs [24] and 15% of all antibiotics prescribed in outpatient clinics are directed toward treating these infections [25]. Furthermore, in the case of pregnant women, these medicines can present deleterious effects on the foetus [22].
Knowledge regarding the treatment of skin and soft tissue infections showed an average score of 63.1 ± 19.4, with a tendency for the use of vancomycin in hospital cases and in necrotising infections. The frequencies of these infections have presented a dramatic increase between 2000 and 2004, with values reaching 29% of total hospitalisation cases. Moreover, they are blamed for 6.3 million visits to the doctor per year. An important proportion of this frequency is linked to the appearance of community acquired infections by methicillin-resistant Staphylococcus aureus (MRSA) [26]. With the appearance of MRSA, the use of vancomycin has become popular, which could explain the students’ tendency to prescribe this antibiotic. However, the use, and particularly the abuse that has been made of it has derived in cases of vancomycin-resistant Staphylococcus aureus. Although resistance to vancomycin has been less critical than predicted because the strains found are not pan-resistant and respond well to commonly used antibiotics such as trimethoprim-sulfamethoxazole or linezolid, it is of utmost importance to insist on prudent use of these antimicrobials starting at their early stages of formation[27].
Interventions directed to the improvement of antibiotic use have been traditionally focused on clinicians and pharmacists [28,29] or have been restricted to evaluating the effects of programmes to control infections associated with healthcare [30]. In medical students, interventions are meagre despite the fact that it is in them that they can have greater effects since they have not yet developed erroneous prescription habits [31]. Some interventions of this kind can be found at universities in the United States [11,32 ,33]. They could make up the basis on which to focus micro and macro curricular academic changes for local universities.
Possible limitations to this study include failure to take into account the study plans of medical schools regarding the use of antibiotics and bacterial resistance. The information gathered was based on self-reporting and three out of six universities in the city were included then external validity is compromised.