General Psychological Burdens

International students exhibited higher scores across all questionnaires (except for fear of contamination), suggesting that they were more anxious, displayed higher depression scores, were more intolerant of uncertainty, and reported stronger fear related to health and body symptomology. Although it is unclear whether differences between the 2 groups of students were present before the COVID-19 pandemic, it is quite striking that those individuals who live abroad and who, therefore, might feel less confident and safe about the context they are living in report higher burdens than those, who know the context (ie, the country) since birth. This finding aligns with the idea that context provides crucial information about the imminence of a threat or whether it will be (or will not be) encountered. ^{Reference Andreatta and Pauli31} . ^{Reference Mobbs, Headley and Ding33,Reference Fanselow57} The SARS-CoV-2 virus is, per se, an unpredictable threat. In other words, human beings do have the ability to detect viruses only through symptoms such as fever, cough, and fatigue. However, some infected individuals may not show any noticeable symptoms. This makes it difficult or incapable to identify SARS-CoV-2 virus. Such incapacity to identify the virus leads to a sustained fear response (also called anxiety response ^{Reference Davis, Walker and Miles27} ) linked to the inability to identify safety. ^{Reference Lohr, Olatunji and Sawchuk28,Reference Mobbs, Headley and Ding33} Because of its unpredictability, the virus can be perceived as quite threatening, ^{Reference Grillon, Baas and Lissek29} and some individuals can be particularly sensitive to such unpredictable threats. ^{Reference Grillon, O’Connell and Lieberman30} We, therefore, suggest that living in a well-known (ie, assuring) context may provide the necessary information to feel safe. In a familiar context, individuals have guidance on how to predict an “encounter” with the virus, and this in turn could reduce the individuals’ psychological burdens.

COVID-19 Related Factors of Emotional and Behavioral Responses

Despite the psychological burdens seeming higher among international students, this difference is not necessarily related to the spread of the virus. As such, we used the COVID-19-related items to investigate whether the students’ psychological burdens were linked to the virus’s spread. We identified 4 factors based on the 16 self-formulated questions on how participants perceived and felt about the spread of the virus. First, the factor labeled COVID-19-related worry grouped 3 items: concerns related to the spread of the coronavirus, the potential severity of the illness, and hoarding behavior. This group of items suggest that being concerned about the consequences of the virus is strongly associated with hoarding-like behaviors (eg, grocery shopping), which is in line with previous studies. ^{Reference Vazirani and Bhattacharjee58,Reference Yoshino, Shimotsukasa and Hashimoto59} Second, the factor labeled perceived risk of infection included items where participants evaluated the risk of getting infected or that someone they know becomes infected. Third, the factor labeled physical distancing grouped questions focusing on how strongly objects and situations, which might be contaminated, are avoided and how strongly safety behaviors such as hand washing are undertaken. Finally, the fourth factor included items on avoiding social contacts, such as meeting someone, traveling, and maintaining distance (labeled as social distancing). These findings were replicated in the whole sample and for each group. Thus, we found that fear of contamination ^{Reference Knowles and Olatunji60} and bodily preoccupations ^{Reference Hein, Gamer and Gall3} predicts safety-like behaviors such as washing hands, maintaining physical distance, or wearing a mask and that fear of contamination is associated with more substantial anxiety of the virus. ^{Reference Ojalehto, Abramowitz and Hellberg61}

Additionally, our model suggests that fear of contamination is not only related to physical distancing but also predicts social distancing, such as avoiding crowded situations or social activities, as well as changing travel plans. Moreover, both of these safety behaviors were also predicted by body vigilance and level of depression, but not by health anxiety or intolerance of uncertainty. These findings support contemporary cognitive-behavioral models, ^{Reference Asmundson, Abramowitz and Richter62,Reference Asmundson and Taylor63} which suggest that health anxiety plays a crucial role in the etiology of mental disorders due to a misinterpretation of the body sensations and catastrophic beliefs about the illness. It is, therefore, conceivable that individuals more vigilant to their body symptoms are more motivated to engage in safety behaviors (ie, physical and social distancing) to prevent the appearance of bodily symptoms. In contrast, individuals with stronger health anxiety or intolerance of uncertainty show more preoccupations because they tend to catastrophize the impact of the virus on health more pronouncedly or because they have fewer resources to endure aversive situations. ^{Reference Mertens, Gerritsen and Duijndam20,Reference Saulnier, Koscinski and Volarov21,Reference Carleton, Fetzner and Hackl43}

Comparison of Dutch and International Students

Of interest, our model outlined a distinct pattern of predictors for national and international students, respectively. Specifically, concerns or worries about the spread of the coronavirus were predicted by intolerance of uncertainty among national students but by health anxiety among international students. In contrast, social and physical distancing was predicted by depression and body vigilance among national students but not among international students. Our model suggests that the factors describing worries for and safety behaviors to the virus were influenced by health-specific characteristics (ie, fear of contamination and health anxiety) among international students, while among national students, the virus-related factors were more influenced by individual-specific characteristics such as depression, intolerance of uncertainty, and body vigilance. As mentioned above, a well-known context might provide the necessary information to feel safe compared with an unfamiliar one. It is, therefore, conceivable that the former is less anxiogenic and definable as a weak situation, while the latter is more anxiogenic and thus defined as a strong situation. Weak and strong situations can allow inter-individual differences to emerge or not, respectively. ^{Reference Lissek, Pine and Grillon64,Reference Monson, Hesley and Chernick65} In light of our results, the inter-individual differences of national students could emerge and predict the response to the virus because these students are in a weak situation. Whereas being in a strong and anxiogenic situation such as the international students determined that contamination-related processes mainly predicted the virus-related responses.

In line with our assumptions, international students had more worries and concerns about the spread of the virus, and they initiated more intense safety-like behaviors (eg, avoidance of possibly contaminated areas or situations with possible social contact), suggesting that either feeling less safe or having higher psychological burdens might lead to more preoccupations and distancing. In contrast, international students did not report a higher perceived risk of infection. This was unexpected, but a possible explanation could be that this factor encompasses distinct mechanisms and is more closely associated with cognitive processes than the other factors. In other words, asking about the risk of contracting the virus may require a cognitive and “cold” evaluation of the situation, while avoidance and worries can be more strongly modulated by an emotional evaluation of the situation. ^{Reference LeDoux and Pine66} Moreover, our model suggests that the perceived risk of infection is not predicted by any of the questionnaires, a finding consistent across both groups. Hence, it seems that affective mechanisms such as being anxious, experiencing fear, or feeling depressed do not influence how the risk is “coldly” estimated.

Our model revealed no effect for anxiety sensitivity, while trait anxiety negatively predicted COVID-19-related factors. At first glance, these results seem contra-intuitive and contrast with previous studies. ^{Reference Warren, Zolfaghari and Fresnedo67} However, the relationship between anxiety sensitivity and fear of coronavirus appeared to be more prominent in the clinical population ^{Reference Rogers, Bogiaizian and Salazar68} or when combined with intolerance of uncertainty. ^{Reference Saulnier, Koscinski and Volarov21} At the same time, prepandemic trait anxiety predicted fear of COVID-19, a prediction qualified in the clinical population. ^{Reference Brosch, Meller and Pfarr69} It is, therefore, conceivable that our sample does not present with “sufficient” clinical scores to detect the association between COVID-19-related factors and anxiety sensitivity or trait anxiety.

Moreover, we did not plan interaction effects between the questionnaires, which may have prevented the detection of different types of structures within the data. To date, few studies have focused on the relationship between trait anxiety and fear of coronavirus. The few known studies that have examined such relationships suggest that pre-pandemic trait anxiety predicts fear of COVID-19, ^{Reference Brosch, Meller and Pfarr69} and increased trait anxiety in university students during the COVID-19 pandemic reduced motivation and increased boredom. ^{Reference Alemany-Arrebola, Rojas-Ruiz and Granda-Vera70} However, both of these results do not apply to our study. Instead, we suggest that highly anxious university students may have found the cost of being isolated too high, leading them to decrease their level of social distancing. Such behavior is similar to what has been observed in patients with spider phobia, where they tend to exhibit less avoidance behavior toward the feared animal if doing so leads to an advantageous result. ^{Reference Pittig, Brand and Pawlikowski71}

Limitations

In the following, we acknowledge 2 limitations of the study. First, knowing where and with whom the students lived during the lockdown may have been an essential factor to consider. It is possible that some of the international students did not remain in the Netherlands during the first lockdown but returned home to their native countries and were within the well-known context. Moreover, returning to their native country might have increased their social contacts (for instance, by living with the family), which in turn may have been a buffer for psychological distress, as studies on social support suggest. ^{Reference Kim, Sherman and Taylor6} Second, our virus-related factors might deviate from the numerous factors observed in the broader literature regarding the psychological burdens of the SAR-CoV-2’s spread. For example, some articles focus on physical distancing (eg, see Hein et al. ^{Reference Hein, Gamer and Gall3} and Knowles et al. ^{Reference Knowles and Olatunji60} ), while others, like us, differentiate between physical and social distancing. Future research should, therefore, precisely define what a safety behavior is, so that we can then better distinguish the underlying processes.