Sharp increase in AMR genes after travelling
A total of 45 students participated in faecal sampling. Before travel, 5 of 45 (11%) students showed a faecal swab positive for blaCTX-M genes, of which 4 swabs contained genes from blaCTX-M-1 group and 1 swab blaCTX-M-9 group. During the stay in India, 35 students tested positive for blaCTX-M genes leading to a total positivity rate for these genes of 78%, which is a significant increase (p < 0.001). Thirty-two of 45 students (68%) acquired a new or additional type of blaCTX-M gene. Of the 45 students, 40 were tested at both time-points during the trip (T1 and T2). Of this subset 27 acquired a new blaCTX-M type during the trip and the majority: 13/27 (58%) were positive at both time-points, 6 only acquired a new blaCTX-M type in T2 and 8 students acquired blaCTX-M or an additional type of blaCTX-M at T1, but lost them again at T2. For blaNDM, only 1 of 45 had a faecal swab positive for this gene prior to travel. An additional 4 students acquired blaNDM during the stay and also this was a significant increase (p < 0.05) (please see Fig. 1).
Global travellers and precautionary purchase of antibiotics
The analysis of the questionnaires showed that the median age of the participants was 27, and the majority of students were female (73%). The cohort of respondents represented a very mobile group, which was shown by their travelling practices. The majority (83%) of respondents visited more than 2 countries within the last three months before their arrival to India. The primary travel destinations were within Europe and included Belgium (37%), Germany (35%), and the Netherlands (30%), but also Canada (13%) and Thailand (10%). All of the participants visited India. These travelling trajectories can be explained by the international nature of the education program that students were involved in. Canada, Thailand and India were the three countries students could opt to go to for an elective. In addition, the proximity of the Netherlands to Belgium and Germany could also have contributed to the high students’ mobility between these countries.
Most of the participants did not take any antibiotics within the last year prior to the study (66%, n = 42), only a quarter of people took one course of antibiotics (25%, n = 16), and several people took 2 or 3 courses (9%, n = 6). Among those who did take antibiotics within the last year prior to the study, more than half was prescribed by a physician (59%, n = 13). However, 41% (n = 11) of those who used antibiotics within the last year informed us that they used non-prescribed antibiotics, which they got either from a family member or from a pharmacist without prescription in countries where it was possible.
Concerning their travel preparation to India, 14 out of 64 respondents reported that they brought antibiotics with them to the trip. The most prevalent antibiotics were azithromycin (42%, n = 5), amoxicillin (33%, n = 4), and ciprofloxacin (25%, n = 3). Two students indicated that it was important to take some antibiotics with them when travelling to India as a precautionary health measure.
Travelling is not considered to be a risk for AMR
While microbiological methods analysed how international travelling may contribute to the acquisition of resistant bacteria, the method of semi-structured interviews was aimed at gaining a deeper contextual understanding of the daily practices that students exercised during their travel. Exploring the meanings of AMR, the interviewees often described this phenomenon in biomedical terms—as an ‘evolution of bacteria to resist antibiotics’. Such descriptions were not surprising as our participants had a background education in health. In addition, the interviewees were also participating in the collection of stool samples and the survey, and therefore they were previously exposed to information about AMR.
Building on a biomedical understanding of AMR our participants described several ways of how AMR can be developed and acquired. We distinguished two of such interrelated ways: first, AMR as an individual responsibility, and AMR as a medical phenomenon that can be acquired in clinical settings. This means that students associated mechanisms of AMR development with antibiotic use, and they connected AMR acquisition with clinical facilities.
In the interviews, students explained that the development of AMR is determined by individual use of antibiotics, including self-treatment, interruption of prescribed antibiotic treatment and its overuse. For instance, our participants explained,
Specific bacterial strains are becoming resistant to antibiotics because of the really often use of antibiotics (S21)
Antibiotic resistance is due to the fact that some people in many countries just taking many multi-resistant [antibiotics]. … The other reason is that many people don’t take the whole prescription that they’re supposed to take (S36)
Individual behaviour with respect to antibiotic use was defined by students as a major cause of AMR. In particular, the excessive amount of antibiotic use was associated with risks of resistance development.
Apart from the individual use of antibiotics, several students highlighted that environmental and infrastructural factors may play a role in AMR acquisition. Some students distinguished between a ‘risky country’ where antibiotics are used inappropriately, and a ‘risky environment’ like hospitals where AMR can be easily acquired by visitors and patients. However, these two definitions of ‘risky’ places are interrelated, as a respondent below explained that the risk of acquiring AMR is higher if a person gets admitted to a hospital in a particular country:
I know that especially some parts of the world, there is a lot of antibiotic use and because of this, this creates like bacteria that are already resistant to antibiotics and stay alive, and if this happened too much you create a resistance strain of antibiotics and I think this is becoming a more urgent issue. (S47)
So I am aware of different countries have different levels of antibiotic resistance. Probably if I get treated in a country where there is like a hospital where there is a lot of bacteria around that are resistant and I am exposed to this, then I might not be able to have them treated. (S20)
AMR, therefore, has been understood by our participants as rooted in individual practices of antibiotic use and in clinical practices of certain countries that create risks for AMR acquisition. These understandings were mirrored in students’ reflections on their health practices and travel preparations. Participants were surprised by our questions about the connection between AMR and travelling and they elaborated that they did not see such as a connection:
I always think about it [AMR] if I ever prescribed antibiotics and when I take it, not when I think of it when I am travelling or some kind, no, no, no. (S42)
While being aware of AMR, its biomedical nature and mechanisms, our participants argued that AMR as a problem was located in clinical settings rather than in public spaces. They did not associate and connect their international travelling practices with the potential risks of acquiring resistant bacteria unless they were admitted to a foreign hospital. This may indicate that while microbiological data highlight the importance of travellers’ social practices for understanding AMR, travellers themselves do not see AMR as a part of their social worlds but rather locate it in the clinical world.