Introduction

Health Care Workers (HCWs) are at risk of occupational exposure to influenza [1,2]. Previous studies demonstrated that 24.1% of students experienced at least one influenza-like illness during influenza seasons [3]. The recent introduction of the novel influenza A/H1N1 virus (“swine flu”) raised concern regarding the safety of HCWs [4,5]. Beyond that, HCWs are the most significant reservoirs for nosocomial transmission of influenza in hospitals [6,7]. Therefore, since 1988 the Standing Committee on Vaccination (STIKO) at the German Robert Koch-Institute (RKI) has recommended that HCWs be vaccinated against influenza to limit the spread of the illness between medical personnel and patients, as well as to reduce staff illness and absenteeism during the influenza period. Nevertheless, compliance rates with influenza vaccination among HCWs remain low [8-12].

Medical and dental students belong to a group of HCWs that is frequently exposed to patients with potentially occupationally-transmissible infectious diseases. Previous studies among college and university students have shown that influenza vaccination was associated with a substantial reduction in influenza-like illness and that influenza vaccination of students is associated with significant health and university performance benefits [3,13].

The purpose of the present study was to ascertain the vaccination rates and beliefs of medical and dental students concerning the seasonal and swine flu vaccination. Furthermore, we assessed the risk perception and behavior modification due to the emergence of a novel influenza virus.

Methods

Study population

. Questionnaire

Ethical considerations

Statistical analysis

Results

Overall, 40.1% of the medical and 36% of the dental students of the clinical part of the Frankfurt medical school (n = 571/1,450) took part in the vaccination campaign and completed the anonymous questionnaire. Only two medical students refused to fill out the questionnaire.

In total, 64.4% (n = 368) of the participants were female, 35.6% (n = 203) male, in accordance with the gender distribution of the student body. Demographic characteristics of the study population are shown in Table 1.

Figure 1

Table 1: Demographic characteristics of participants (n = 571)

Since only students who took part on the questionnaire could be evaluated, the following analysis is limited to the 571 participants. Overall, 81.4% (n = 465) of the students were vaccinated against swine flu, and 51.1% (n = 292) received the swine flu and seasonal influenza vaccination. In total, 69.7% (n = 398) of the students were vaccinated against seasonal influenza.

Medical students demonstrated a higher vaccination rate with both vaccines compared to dental students (54.9% vs. 31.1%; p < 0.001), while dental students were significantly more often vaccinated against the seasonal flu alone (p < 0.001). When comparing the overall vaccination rate against the seasonal flu, no significant differences could be highlighted (76.7% vs. 68.4%; p = 0.117). Vaccination rates are summarized in Table 2.

Figure 2

Table 2: Vaccination rates among respondents, medical students (n = 481 / 1,200) and dental students (n = 90 / 250)

In total, 57.8% (n = 330) of the participants had never had a flu vaccination in the past, 20.3% (n = 116) were vaccinated against flu on a single occasion, and 21.9% (n = 125) frequently received the flu vaccine.

Reasons mentioned for compliance with seasonal and swine flu vaccination (See Table 3) were primarily protection of patients (stated by over 90% of the students), and self-protection (stated by over 70%). Concern for their family, friends and colleagues took third place. These results were broadly similar for medical and dental students. Only for swine flu vaccination did significantly more medical students declare the reason for vaccination as being the protection of their families and friends (p = 0.003). Significant more dental students noted that they had refused previous seasonal influenza vaccination because they had thought that the “vaccine does not work” (p = 0.038), or they had feared side effects (p = 0.038) or they were convinced that the vaccine could cause flu (p < 0.001).

Figure 3

Table 3: Reasons cited for acceptance and refusal of seasonal and swine flu vaccination (n = 571) – multiple answers were possible

Approximately 90% of medical and dental students stated that the risk of occupational exposure to and subsequent contraction of seasonal and H1N1 influenza was elevated in comparison with the entire population (see Table 4).

Figure 4

Table 4: Risk perception concerning seasonal and H1N1/2009 influenza (n = 571)

In total, 56% (n = 320) of the students did not change their “risk-prevention” behavior due to the emergence of the novel influenza virus H1N1/2009. Notably, 40.6% (n = 232) stated that they washed their hands more often and 6% (n = 34) tried to avoid gathering, 6.7% (n = 38) stopped handshaking and 3.2% (n = 18) bought masks, disinfectants and/or antiviral drugs. There were statistically significant differences between medical and dental students regarding their behavior modification. More medical than dental students did not change their behavior (p < 0.001), while significantly more dental students washed their hands more often (p < 0.001), avoided gatherings (p = 0.024) and increased the frequency of wearing masks (p < 0.001) (see Table 5).

Figure 5

Table 5: Behavior modification due to the emergence of H1N1/2009 influenza (n = 571).

Discussion

Our study is the first study to look at risk perception for seasonal and H1N1/2009 influenza infection in medical students. We examined risk perception, immunization rates, and behavior modification due to the emergence of a novel influenza virus. We built and expanded on our past work by examining a new population (medical and dental students) [9,14].

In our previous studies on HCWs, self-protection was the most frequently cited reason for receiving the flu vaccine [9,14]. Notwithstanding, the medical students mentioned the reduction of the risk to infect patients as the most important motivation associated with seasonal and swine flu vaccine uptake (see Table 3). This illustrates the consciousness of students being aware of their potential contribution to influenza transmission to patients.

Medical students are, during their clerkships and internships, commonly responsible for the collection of blood samples from a whole ward, and therefore they come into contact with many or all patients of the department. Their unique profile makes them potential “superspreaders” for e.g. aerogen-transmitted infectious diseases [15]. The immunization of medical students might be highly effective in preventing nosocomial influenza outbreaks, because they belong to an age group with high infection rates of H1N1/2009 [16].

Evidence from the past few months demonstrates that the H1N1/2009 virus has rapidly established itself and is now the dominant influenza strain in most parts of the world [16].

Vaccination seems to be the best defense against high infection rates among susceptible and vulnerable people. However, physical interventions (e.g. personal hygiene, barriers, and distancing) are effective against the spread of a broad range of respiratory viruses and ought not be neglected. One major problem with physical measures is poor compliance because all physical interventions (e.g. washing hands frequently, wearing masks, gloves, and gowns) require a change in behavior [17]. However, a recently published study revealed that simple hand washing with unmedicated soap and water appears to be highly effective in removing the influenza virus and is, therefore, likely to be effective in preventing the transmission of influenza by smear infection [18].

A study from the University of Alberta in Canada found that 93.5% of medical students believed that hand washing was an effective preventive measure in limiting the spread of influenza. However, it is important to note, that there is a difference between students knowing (data from the University of Canada) and complying with preventive measures (our data) [19].

Most of the medical and dental students stated that their risk of acquiring a seasonal or swine flu infection was elevated due to their professional life.

Nevertheless, 56% of participating students stated that they did not change their behavior due to the emergence of the novel influenza virus. Merely 40.6% mentioned that they washed their hands more frequently, there seems to be a discrepancy resulting from inconsistency between student's beliefs and student's actions.

There are major similarities between medical and dental students, but there are some differences. First, medical students exhibited a higher vaccination rate compared with dental students. Second, significantly more medical than dental students declared the reason for their swine flu vaccination was the protection of their families and friends (p = 0.003). Third, while significantly more dental students had refused previous seasonal influenza vaccination because of misinformation (“vaccine does not work; vaccine causes flu; relevant side effects”), with the appearance of the pandemic flu, this seems to have changed to a certain extent so that they now show a higher risk perception and a significantly higher rate in the modification of their “risk-prevention” behavior compared with medical students.

Limitations

To appreciate the results of our study, some potential limitations need to be addressed:

First, the results from a single academic institution may not be applicable to other institutions.

Second, the “social desirability bias”, (i.e. selecting a choice of answers considered as being the most “socially favorable”) may lead to bias in our survey, which may affect the reliability of some of the answers.

Third, because of the restricted observed time frame (November 2 until November 30, 2009); we were unable to measure whether the actions and beliefs of the students varied during the entire influenza season due to the number of reported influenza infections and owing to the changing awareness of media and public sentiment. However, the vaccination campaign started on November 2, and all official immunization dates were until November 30, 2009. All students might have been able to keep a vaccination appointment, but it is likely that some of the students failed to meet the deadline.

Fourth, the number of students who received their flu vaccination from their general practitioner could not be calculated.

However, only few studies deal with the occupational risk of infection among medical students who belong, obviously, to a group of workers who are at greater risk of infection compared to the general population. Most of the previous studies focused on hospital-based HCWs (e.g. physicians, nurses). Our study is the first study that has evaluated the influenza vaccination rate, the risk perception and behavior modification among German medical and dental students due to the emergence of a novel influenza virus (H1N1/2009). Albeit, nearly 90% of medical and dental students stated that the risk of occupational exposure to and subsequent contraction of seasonal and H1N1 influenza was elevated in comparison with the entire population, more than half of the students did not change their “risk-prevention” behavior owing to the emergence of the novel influenza virus H1N1/2009.

The results of our study underscore the need for ongoing focus on and evaluation of strategies to reduce the transmission of flu among HCWs. Further work is needed to highlight the important role of physical measures such as hand washing and wearing masks. Strategies to increase influenza vaccination uptake among medical and dental students ought to be implemented in order to protect the students and patients from influenza [20].

Acknowledgement

The authors would like to thank the participants of the study for their time and effort in completing the questionnaire and their valuable suggestions regarding the project.