Three major trends emerged from studies on emotions and mental health during previous pandemics: people show increased anxiety, depression, and stress symptoms. A study by Liu et al. [11] explored how the SARS outbreak in Beijing had influenced medical staff‘s psychopathology for 3 years post-pandemic. In one study, physicians and nurses who had high pandemic exposure were split into two groups based on having been quarantined or not, and were surveyed using the Centre for Epidemiological Studies Depression Scale (CES-D) [14] and the Impact of Event Scale-Revised (IES-R) [15] for PTSD symptoms. Health care workers studied in the work by Liu et al. [11] had been quarantined for around 10 days together with SARS patients and were taking care of them. They could not see their families and were at high risk of infection, which could have inflated their psychopathology symptoms throughout time. They were tested three years after that period. It appeared that participants who had been quarantined and had previous traumatic experiences had higher depressive symptoms. Being 35 years old or younger and being single were also predictive of higher depressive symptoms post-pandemic.

Anxiety increase was recorded and analyzed by Jeong et al. [16] in Korea during isolation periods of MERS and for 4-6 months afterward. People infected with MERS were compared against healthy but isolated people on the Generalized Anxiety Disorder scale (GAD-7) [17] and the Korean version of the State-Trait Anger Expression Inventory (STAXI) [18]. During isolation, 47.2% of MERS patients and 7.6% of quarantined people had anxiety symptoms, when general population prevalence was around 3.3% [16]. After 4-6 months post-pandemic, numbers decreased to 19.4% for MERS patients and 3.0% for isolated healthy people, showing possible recovery to normal anxiety levels. Anger trends were similar to anxiety, but with a bigger decrease. However, Jeong et al. [16] reported that around 30% of people did not agree to answer questions on the phone and were swearing at the researchers. If this had been included in the data analysis, it could have shown higher anger results in the study.

The prominent psychological impact of quarantine is increased stress symptoms, as explored by Hawryluck et al. [8]. A web-based survey with questions from PTSD (IES-R [15];) and depression (CES-D [14];) scales were conducted in Toronto, Canada, around 36 days after SARS quarantine. More than half of respondents were healthcare workers aged 26-45, the majority having college-level education or higher, and most had medium to high levels of income. The isolation period was on average 10 days, and survey respondents were questioned on knowledge and understanding of the reasons for the quarantine, what they knew about infection control measures and where they found that information. Researchers used cut-off points that clinically diagnose PTSD and depression disorders and found that 28.9% and 31.2% of quarantined people met the criteria for PTSD and depression accordingly. Depressive and PTSD symptoms were strongly correlated together (r = 0.78) and an increase of both was predicted by household income - lower-income led to more pronounced symptoms. Neither age, level of education, nor career choice had any influence, although a longer duration of quarantine significantly predicted higher PTSD symptoms. No such trend was found with depression levels, however, the study participants were isolated only for around 10 days and we might suppose that different results could emerge from longer quarantine periods.

The aforementioned findings of increased anxiety, depression, and PTSD symptoms due to quarantine or pandemics generally might depend on certain risk factors. According to Brooks et al. [7], in an extensive literature review, healthcare workers were more severely distressed than the general public, especially if they were quarantined. In fact, most studies report higher risks for healthcare workers during pandemics, but most of them do not compare their results with the results of the general public. The study that did so found no significant correlations between being a healthcare worker and showing greater PTSD symptoms [8]. This could be because healthcare workers had a better understanding of quarantine measures and had a better understanding of the situation. Another risk factor mentioned by some researchers [16] is a history of mental illness. People who have pre-existing mental conditions are more at risk during quarantine, as they have weak emotional control and rely more on social support. This implies that they require additional support to protect their mental health during quarantine and isolation.

Some studies suggest that the elderly are at the greatest risk, not only because of being in the COVID-19 health risk group, but also because they are more susceptible to depression and anxiety. A longitudinal study found a pattern of social disconnectedness predicting perceived isolation which in turn predicts depression and anxiety symptoms [19]. In other words, having a smaller social network or fewer social interactions leads to loneliness and a perceived lack of support, which predict the severity of depression and anxiety. Due to coronavirus regulations to stay at home, the elderly are at greater risk of feeling lonely, unsupported, depressed and anxious about themselves and others. An alarming finding from some researchers [20] suggests that perceived social isolation has the same detrimental effects as real physical isolation. Their experiments with isolated non-human social species show multiple physical damages, especially on the HPA axis that regulates sleep, mood, and stress. So, since the elderly were put at actual physical isolation and perhaps already had fewer social interactions, the risk only increases.

Stressors for emotional distress resulting from quarantine have been summarized in a systematic review [7]. Duration of quarantine is one of the factors influencing PTSD symptoms, anger, and avoidance behaviors as seen from comparisons of people quarantined for more or less than 10 days. It is yet unknown how long-term COVID-19 quarantines of 2 months or longer will impact people’s emotions. During the SARS pandemic, people felt bored and frustrated in home isolation, having restricted contact with loved ones, with routine activities coming to a halt. Psychological distress has been intensified due to inadequate supplies of food, water, and accommodation for some people, as well as restricted to medical care not related to SARS. People were angry and confused when responsible healthcare authorities spread inadequate information and unclear guidelines during the SARS pandemic. Lack of transparency from such authorities and explanation for their course of actions led to violation of quarantine rules and it decreased the public trust [7].

One of the major factors influencing psychological distress is financial losses due to quarantine as people are unable to work, have little savings, and so on. It is also a risk factor for increased anger and anxiety symptoms, lasting months after quarantine [16]. Hawryluck et al. [8] found that low income before quarantine predicts higher PTSD and depression symptoms, so it could be assumed that these people might experience even higher symptoms by losing money during quarantine. They have more to lose as their household incomes are lower, and it predicts higher psychological distress [7].

The stigma surrounding risk groups and people of high exposure to the virus adds to psychological distress after quarantine. Multiple studies mentioned the [7] review have found stigmatization of people who have been quarantined during previous SARS outbreaks. Participants reported people avoiding them, treating them with fear and suspicion, making comments about them. Similarly, during the Ebola outbreak, some people were unable to resume their jobs as it seemed too risky for them or because colleagues expressed fear of contagion.

Multiple studies have observed gender differences in the prevalence and severity of depression and anxiety symptoms. Globally the female to male ratio is 1.7:1 as women are almost twice as likely to be diagnosed with depression than men [21]. Multiple studies across countries find similar prevalence, indicating that biological sex differences have more influence than socio-economic factors. The main explanation is that women experience hormonal fluctuations across life during the stages of puberty, menstruation, pregnancy, and menopause, which could trigger the onset of depression. Women are more emotional and report depression symptoms more often than men, who externalize their feelings in such ways as anger or misuse of alcohol [21]. Gender roles are important, as men and women have different social needs, which result in different behaviors when unmet. Women report higher loneliness and depressive symptoms as their social needs are more complex and demanding [22]. Meanwhile, men are more reluctant to directly admit to feeling lonely as they grow up and they are expected to be more socially independent.

An electroencephalography (EEG) study [23] found gender differences in a threat startle paradigm measuring neural-level sensitivity and its link to anxiety and panic symptoms. It was found that women have higher startle potentiation in both predictable and unpredictable threat conditions compared to men. Females also reported higher panic symptoms in anticipation of an unpredictable threat, showing higher anxiety levels concerning unpredictable future events. Across both genders, greater panic symptoms were associated with higher startle potentiation in an unpredictable threat condition, but no significant link was found in the predictable condition. This indicates that genders differ in panic symptoms experiences because they show different startle reflex in anticipation of unpredictable physical threats. Yet, both men and women with heightened sensitivity to unpredictable threats can show greater panic and anxiety symptoms due to increased startle potentiation. Burani and Nelson [23] did not give any suggestions for follow-up studies, but we think their findings might be put to the test by researching gender differences in emotional reactions during COVID-19.

A longitudinal study of the elderly aged 57-85 years found associations between social isolation and disconnectedness on anxiety and depression symptoms [19]. The fewer social connections and activities they had, the more anxious and depressed they felt. Even though no younger people were recruited for comparison in this study, it still shows an increased risk for the elderly to be more anxious and depressed. However, not only do older people feel lonely and sad, more than half of the adolescents say they “sometimes feel lonely” too [22]. During adolescence, youngsters explore which friendships work, how their expectations are met, and so on. Yet the elderly, aged 80 years and more, feel lonely more often, as their personal networks shrink with time. Feelings of loneliness serve an evolutionary function to motivate people to reconnect with others. It motivates both young and old people to be more socially active, seek out support when needed and enjoy life by sharing it with others.

Interesting differences in PTSD prevalence were observed across the lifespan of men and women [24]. The highest prevalence of PTSD in men was at 41-45 years of age, for women at 51-55 years, whilst for both, the lowest was at 71-75 years. Men have quite stable levels of PTSD risk, yet it peaks in the early 40s as they usually take on more responsibilities in life (work, family, etc.) or potentially reach a midlife crisis. Women have an increased risk around the early 20s - a time of frequent changes (career, pregnancy) combined with social pressures on “being a modern woman“. Both genders aged 60 and above start showing a decline in PTSD risk as they are thought to accept their imminent death and use early life experiences to cope with it. Using the wisdom of retrospect, they usually solve the crisis between ego and despair of old age, which shows in lower PTSD symptoms [24].

The negative consequences of quarantine are increased anxiety, depression, and stress symptoms, which might last long after the quarantine ends. Nine percent of health-care workers remained highly depressed 3 years after SARS quarantine [11]; MERS patients and healthy quarantined people stayed anxious 4-6 months after isolation [22]; up to 36 days after SARS quarantine, high PTSD symptoms were still prevalent amongst the general population [8]. Longitudinal studies on emotional change during the COVID-19 pandemic are still in progress, although China has shared its first analysis. Wang et al. [10] had surveyed the general Chinese population once when the cases of infections were rapidly increasing, and a month later when they were declining. More than 1,700 people responded to the survey, yet only around 300 people responded both times; remaining people responded once, either first or second time. Stress, anxiety, depression, and PTSD symptoms were measured using the IES-R [15] and Depression, Anxiety, and Stress Scale (DASS-21) [25] as in previous studies, yet contrary results were found. None of the scores, except for the PTSD scale, differed significantly between the first and second time of questioning. Only PTSD scores were significantly lower the second time, yet both times they were high enough to indicate a strong presence of symptoms. The researchers assumed that it was probably due to rapid and decisive measures taken by the Chinese government that people’s emotions remained stable [10]. Additionally, people aged 12 to 21.4 years had higher PTSD scores than those aged 49.6 to 59 years. Students reported struggling to study remotely, expressed uncertainty and stress about their school or college exams.

An explorative paper has been issued by early-career psychiatrists proposing an emotional curve framework that predicts emotion change during COVID-19 [26]. Young practitioners from World Health Organization regions discussed their countries’ mental health systems, preparations for coronavirus, economic plans, etc. An extensive literature review was combined with data gathered from country respondents, and a conceptual framework was created. After working on feedback, a final version of the emotional curve with double-peak emotional distress has been conceptualized. It shows initial distress to the pandemic, then community growing resilience, and another distress wave coming post-pandemic as mental disorder prevalence increases.

The most prominent consequences would be the aforementioned internal psychological struggles, such as anxiety, depression, and acute stress, as well as relapse to preexisting mental conditions. According to Ransing et al. [26], the second peak of distress comes either due to the second wave of COVID-19 cases, or people losing loved ones, or big economic and social disruptions happening. A phenomenon called ‘emotional contagion is also at play when people manifest their anxiety, anger or other moods across populations. It easily happens in today’s digitalized and global world, especially on social media platforms where people share their thoughts and feelings with thousands, indirectly ‘infecting’ them with their emotions.

China was the first country hit by COVID-19, revealing the impact it had on communities, psychologically and socially. A web-based study [27] surveyed China’s residents for their psychiatric symptoms and feelings of returning to work. Additionally to the diagnostic measures for anxiety, depression, and stress, questions on COVID-19 preventative hygiene recommendations and organizational measures were asked. Higher psychiatric symptoms were found to be associated with poor physical health and viewing return to work as a serious health hazard. As expected, adherence to hand hygiene recommendations, wearing face masks, and seeing safety improvements in workplaces meant people showed less severe psychiatric symptoms. Counterintuitively, returning to work did not result in increased severe stress, but workers group showed a much lower prevalence of symptoms compared to previous China‘s population surveys [27]. This could be because of very strict preventative and safety measures implemented nationally in China that contrast with much milder regulations when people resumed working again.

The present study explores how the general population of Lithuania felt during the COVID-19 pandemic during the national quarantine. From 30^th of March to 8^th of June, 2020 a representative group of Lithuanian citizens 18-74 years of age were surveyed five times on their emotional states. The goal of the current study was to research the emotional reactions and changes of the population of Lithuania during quarantine.

Based on previous studies, we expected to find certain trends in emotional reactions to COVID-19, that is, different reactions between men and women and between age groups.

In total, 2634 participants (1536 females and 1098 males) aged 18 to 74 years (M = 42.94, SD = 13.13) were interviewed. National representative samples of Lithuanians were surveyed and analyzed, grouped into 18-29 years old group (N = 496), 30-49 years group (N = 1159), and 50-74 group (N = 979). In each wave of survey different representative sample of Lithuania, inhabitants were interviewed. During the time span of 70 days in lockdown, surveys were completed five times (each poll ending date March 30^th, April 8^th, April 30^th, May 21^st, June 8^th) using a computer-assisted web interviewing method. Questions from Gallup’s Global Emotions Report [1] were used to evaluate emotions, stress and pain: “Did you experience the following feelings most of the day yesterday? How about physical pain?”. Correspondingly questions about anxiety, sadness, stress, anger, enjoyment, calmness and physical pain were asked for evaluation. Demographic information of age and gender was collected as well. Emotion states were explored and compared across five waves of survey.

We had two predictor variables of gender (male, female) and three independent variables of age (18-29, 30-49, 50-74) based on demographic information provided by participants. There were seven dependent variables of self-reported emotions and states, including anxiety, sadness, anger, enjoyment, calmness, stress, and physical pain.

A between-subjects t-test was run on SPSS V.26 to compare male and female answers to each feeling question. One-way ANOVA with Tukey’s HSD post hoc test was used to compare three age groups on the same answers.

Across the five polls and all age groups, significantly more females (M = 0.43, SD = 0.495) than males (M = 0.37, SD = 0.484) expressed feeling stressed, t(2632) = -2.86, p < 0.05.

One-way ANOVA showed that stress differed statistically significantly between different age groups, F(2, 2631) = 31.04, p < 0.001. A Tukey HSD post hoc revealed that stress statistically decreased going upwards from the 18-29 age group (M = 0.53, SD = 0.499) to the 30-49 age group (M = 0.42, SD = 0.494) and to the 50-74 age group (M = 0.32, SD = 0.269), p < 0.001 (Figs. 1 and 2).

Fig. (1). Stress prevalence between males and females.

Fig. (2). Stress prevalence across different age groups and poll times.

Fig. (3). Anxiety prevalence of males and females across.

Fig. (4). Anxiety prevalence across age groups and poll times.