**1. Introduction**

A new viral disease due to the infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been named by the World Health Organization (WHO) as the coronavirus disease 2019 (COVID-19) and announced as a pandemic approximately five months after the 41 first reported cases of pneumonia in Wuhan, China [1–3]. Before it was officially reported as a pandemic, the spread of the SARS-CoV-2 has affected 114 countries, leading to nearly 188,000 infections, among which thousands of them included critical cases, as well as over 4000 deaths [4,5]. According to the most recent statistics, there are more than 100 million cases confirmed so far, and the number of new cases (confirmed or fatal) is continually increasing every other day.

Forma, A.; Karakuła, K.; Sitarz, E.; Bogucki, J.; Karakula-Juchnowicz, H. The Outbreak of SARS-CoV-2 Pandemic and the Well-Being of Polish Students: The Risk Factors of the Emotional Distress during COVID-19 Lockdown. *J. Clin. Med.* **2021**, *10*, 944. https://doi.org/10.3390/jcm10050944

**Citation:** Juchnowicz, D.; Baj, J.;

Academic Editors: Michele Roccella and Giacomo Mancini

Received: 2 January 2021 Accepted: 22 February 2021 Published: 1 March 2021

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**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Compared to the severe acute respiratory syndrome coronavirus (SARS-CoV) or the Middle East respiratory syndrome coronavirus (MERS-CoV), SARS-CoV-2 has affected a significantly greater number of people during the outbreak of the pandemic, mainly due to its higher transmission potential [6] and its efficient spread by various transmission routes including airborne, contact, or fecal-oral routes [7,8]. Several factors such as gender, age, or the presence of concomitant diseases have and an impact on the severity of SARS-CoV-2 infection that might range from the asymptomatic infection to the clinical conditions characterized by severe respiratory failure or death [5,8]. Factors that contribute to the higher risk of mortality rates of the infected patients include cardiovascular diseases, hypertension, respiratory diseases, diabetes, older age, obesity [6,8], or vitamin D deficiency [9].

According to the WHO, on 26 April 2020, which was the closing day of our survey, the course of events proceeded as follows—2,804,796 confirmed cases, 193,710 confirmed deaths [10]. From the date of the outbreak, in order to prevent the spread of the virus, many governments ordered the first recommendations regarding national lockdowns as well as traveling restrictions [11]. In Poland, on the same date (26 April 2020), there were 11,617 officially confirmed cases and 535 deaths already reported [12]. Numerous restrictions introduced by the governmental measures and public health recommendations during the COVID-19 pandemic have affected the daily living of the society, and those that primarily mattered were social distancing, social isolation, and home confinement. On 23 March, the Polish government announced a state of emergency due to the SARS-CoV-2 pandemic, and all schools and universities were closed [13]. From the 1 April till 26 April, people were not allowed to go out except in special cases such as work and going to the pharmacy, hospital, and grocery shops, besides, strict restrictions regarding the total number of customers who were allowed to be in the same room were introduced by the government. Moreover, the hours between 10 am and 12 am have been declared as 'the hours for seniors only' in all of the open institutions; parks, forests, and boulevards have been closed for all other citizens. Juveniles under 18 years old were not allowed to walk unsupervised by an adult [14]. People started to self-isolate, equipped with excess food, protective masks, and disinfectants. Incidences of shortages of masks and health equipment in numerous hospitals and pharmacies occurred [15]. Throughout the pandemic, information on the transmission dynamics, incubation time, basic reproductive frequency of COVID-19, or symptoms and clinical manifestations of the infection were unclear and continually changing. The absence of a specific cure or vaccine made the public more concerned about their health [16].

The risk of infection or death was not the only problem that was concerning society. Reports on the expansion of SARS-CoV-2 infection and new incidents of confirmed or fatal COVID-19 cases were more likely to be causing fear, anxiety, and distress [17]. The rapid spread of the virus, social isolation, changing of the command habits, many restrictions, postponing exams, reopening of schools and universities are pressuring the mental health of societies [10]. Moreover, the stigmatization or even discrimination of the individuals who might be associated with the area of spread of disease (e.g., healthcare workers) might be even more distressing [18]. In 2002, during the SARS pandemic, studies showed that the psychological impact on the non-infected community was higher in the younger population; besides, they presented with an increased self-blame, which could reflect frustration and guilt related to responsibility attribution [19]. There is an increasing number of studies that aim to assess the mental health of the general population during the COVID-19 pandemic; however, the long-term consequences remain questionable [20].
