The present study revealed that medical students exhibit poor knowledge regarding antibiotic use, with the scores between 44.2 (9.9) and 63.1 (19.4) points. Typically, students perceive that training received from the university regarding the topic is insufficient. In this regard, it is important to remember that the WHO has highlighted the importance of improving the training of undergraduate students with regard to antibiotic use as one of the main strategies to preserve their effectiveness of antibiotics [9,10]. However, the results of the present study, along with those reported for students from the United States , Spain , and seven other European countries  reflect that education regarding this topic remains inadequate.
The interpretation of antibiograms was highlighted among the topics in which the students considered that they received insufficient training by the university, with 43.5% of the students stating this. This finding is similar to that of an investigation conducted in students in China, where the frequency of dissatisfaction with the education received to interpret antibiograms was 71.7% . The interpretation of antibiograms is a fundamental competence for trainee doctors because it guides the detection of the new resistance mechanisms, knowledge of the epidemiology in a defined geographical area, and choice of antimicrobial treatment. However, the interpretation of an antibiogram is a complex exercise that involves appropriate knowledge, for instance, the knowledge that there are antibiotics that are only slightly affected by the resistance mechanisms and hence are reported as sensitive in inhibitory tests in cases when they are resistant is crucial. A classic example is the false sensitivity of Salmonella spp. to ciprofloxacin and levofloxacin, despite these isolates being resistant to nalidixic acid. Similarly, the knowledge regarding the false sensitivity of Staphylococcus aureus to amikacin and tobramycin, when the organism is resistant to gentamicin, is important . Failure to recognize these characteristics has an impact in the choice of therapy—it leads to therapeutic failure, omits the reporting of new resistance mechanisms and increases costs owing to the requirement of specialized diagnostic tests. Therefore, teaching in this field constitutes a challenge for the city medical schools. Nevertheless, it is necessary to complement these actions by encouraging their mission as promoters of health education, particularly to ensure that patients follow medical recommendations and adhere to therapies.
With regard to knowledge about the treatment of specific infections, it was found to be low for respiratory tract infections due to a tendency toward the indiscriminate azithromycin use, otitis treatment selection in children, and antibiotic use in cases of acute pneumonia. This finding is consistent with previous studies conducted in practicing physicians that found that 45%–64.2%  of antibiotic prescriptions for patients with respiratory tract infections are inadequate . Particularly, in medical students, it has been observed that 18.1% considered that antibiotics are useful for the treatment of viral respiratory tract infections . These findings demonstrate that it is crucial to improve the knowledge of the treatment of respiratory tract infections in trainee physicians, because these infections are among the 10 main causes of morbidity and mortality in the general population and among the first 3 causes in the pediatric population ; moreover, cases of pneumonia are the leading cause of death due to infectious diseases . A lack of improvement of the knowledge contains two implications. On the one hand, antibiotic prescriptions for cases in which they are not indicated contribute to the selection pressure for resistant microorganisms. On the other hand, appropriate treatment is delayed, contributing to morbidity and mortality.
With regard to UTIs, the mean score for this ratio was 58.7 (14.8) points, with a high proportion of students stating that all asymptomatic urinary infections in women with diabetes women must be treated and that the first choice of treating a UTI must be ampicillin/sulbactam. This finding is consistent with that of another investigation conducted in which 47.3% of the students do not identify the appropriate UTI therapy . In addition to errors pertaining to the appropriate therapy, research conducted on practicing physicians found that only 41% of antibiotic prescriptions for these types of infections are written according to the recommended dosing, interval, and duration . It has been described that in up to 96% of cases, antibiotics that are not indicated for UTIs in pregnant women are being prescribed . Errors in antibiotic prescriptions for these types of infections is a crucial issue, considering that UTIs are one of the most common causes of doctor visits at the primary care level, affecting approximately 150 million individuals annually worldwide . In the United States, these cases are the cause for 0.7% of all outpatient visits. It is estimated that annually, 7 million women seek medical care due to UTIs , and 15% of all antibiotics prescribed in outpatient clinics are directed toward treating these infections . Furthermore, in the case of pregnant women, these medicines can present deleterious effects on the fetus .
The knowledge regarding the treatment of skin and soft tissue infections showed a mean score of 63.1 (19.4), with a tendency for vancomycin use in nosocomial cases and in necrotizing infections. The frequencies of these infections have presented a dramatic increase between 2000 and 2004, with values reaching 29% of total hospitalization cases. Moreover, they are attributed for 6.3 million visits to the doctor annually. An important proportion of this frequency is linked to the appearance of community acquired infections by methicillin-resistant S. aureus (MRSA) . With the appearance of MRSA, vancomycin use has become popular, which could explain the students’ tendency to prescribe this antibiotic. However, the use and abuse of this drug has led to cases of vancomycin-resistant S. aureus. Although resistance to vancomycin is less critical than predicted because the strains identified are not pan-resistant and are susceptible to commonly used antibiotics, such as trimethoprim–sulfamethoxazole or linezolid, it is of utmost importance to insist on the prudent use of these antimicrobials at their early stages of formation .
Interventions directed to the improvement of antibiotic use have traditionally been focused on clinicians and pharmacists [28, 29] or have been restricted to evaluating the effects of programs to control infections associated with healthcare . Among medical students, interventions are inadequate, despite the potential to exert substantial effects in them because they have not yet developed erroneous prescription habits . Some interventions of this kind can be found at universities in the United States [11, 32, 33]. One of the main measures that can be undertaken to improve the knowledge and ability for the appropriate medication use among medical students is the personal drug selection method. This method, suggested by the WHO  has successfully been applied in different countries such as Nepal  and Japan . Similarly, Silverberg et al.  conducted a review of recent literature in which they identified 48 articles, distributed worldwide, with different teaching methodologies on antibiotic administration in undergraduate and postgraduate medical education, and although that study showed that medical schools worldwide are implementing interventions on this topic, a rigorous evaluation of interventions is required to determine if such efforts have indeed been effective. Such interventions and evaluation could provide a basis on which to focus micro- and macro-curricular academic changes for local universities.
The possible limitations to this study include failure to consider the study plans of medical schools regarding antibiotic use and bacterial resistance. The information gathered was based on self-reporting questionnaire, and because three of the six universities in the city were included, external validity was compromised.