Supervised by: Yuhui Zhou, BA (Hons). Yuhui is a 5th year medical student at the University of Cambridge. She gained a First class degree in her intercalated year studying Pathology. She has an interest in Cancer & Immunology and has been awarded a Wellcome Trust Biomedical Vacation Scholarship to study host responses to infection.


Coronavirus is an infectious disease caused by the SARS-CoV-2 virus. It can be spread from an infected person’s mouth or nose, contained in small liquid particles when they cough, sneeze, speak, sing, or exhale. In order to temporarily stop the rapid spreading of the virus and reduce case numbers, governments from over 100 countries decided to plunge their nations into either full or partial lockdowns starting in late 2019. However, lockdowns have shaken up, taken, and reshaped lives everywhere. It significantly impacted on the population’s mental health – especially those most vulnerable – as it was the single greatest source of pandemic-related stress.

The definition of the word “vulnerable” in the Cambridge dictionary is someone who is “able to be easily physically or mentally hurt, influenced or attacked”. We identified children and adolescents, healthcare workers and the impoverished as the three groups that are the most vulnerable to the detrimental effects of lockdowns on mental health. This is due to the enormous changes incurred on their life habits as a result of national lockdowns. School-aged children, for example, were forced to do online schooling which markedly increases their average screen time and decreases green time; toddlers had decreased opportunities to connect with outdoor environments; and children of all ages may have been separated from parents. On the other side of the pandemic, healthcare workers were the people in closest regular contact with the virus, which undoubtedly increased the likelihood of them falling ill. Additionally, food supply shortages and an increased cost of living furthered the existing vulnerability of those living on or below the poverty line.

This paper undertakes to determine the impact of the COVID-19 pandemic on these vulnerable groups. Perhaps the most apt place to begin this is by considering fear. Fear is an adaptive defense mechanism that is fundamental for survival. However, to what degree should one be afraid of COVID-19? Should the aforementioned vulnerable groups experience greater fear than others? Ultimately, at a certain point, all difficulties and changes in lifestyle will lead to an increase in psychological symptoms – anxiety, depression, mental disorders, PTSD, etc – all of which will require some degree of mental health treatment.

Since the outbreak of the COVID-19 pandemic, there has been lots of research done to determine people’s mental health changes during the lockdowns. Nonetheless, few of them targeted the most vulnerable groups, which often require the most support and care. 

This research paper will mainly look at countries that have experienced lockdowns, notably the UK, the US, China, India, and Australia. Our aim is to provide a list of typical factors, whether social, economic or biological, that lead to the mental health concerns seen among vulnerable groups. We will combine and organize the current, available and useful statistics to help provide a comprehensive explanation of how lockdowns are affecting the mental health of children, healthcare workers, and the impoverished. 

Please note, this paper was written in April 2022 and all facts and statistics were accurate at the point of writing.



Adolescents and school-aged children

COVID-19 lockdowns triggered the temporary closure of schools across the world. To meet the need for social distancing restrictions, online schooling was introduced. Therefore, an increase in screen time was unavoidable. According to an article published in Nature, children spent more time in front of screens during lockdowns than they did in the months immediately before them (Christina Bergmann et al.).

Figure 1 shows that the number of students that have an average screen time of over 1-4 hours increased significantly, especially in the UK, while time under 30 minutes has decreased. The rise in screen time is closely associated with psycho-social problems, like lower self-esteem. The prevalence of depression among adolescents was around 35-44% when last measured prior to the pandemic, the rate of anxiety was 19-37%, and psychological distress was 40%. A study in ScienceDirect determined that “among 14- to 17-year-olds, high users of screens (7+ h/day vs. low users of 1 h/day) were more than twice as likely to ever have been diagnosed with depression (RR 2.39, 95% CI 1.54, 3.70), ever diagnosed with anxiety (RR 2.26, CI 1.59, 3.22), treated by a mental health professional (RR 2.22, CI 1.62, 3.03) or have taken medication for a psychological or behavioral issue (RR 2.99, CI 1.94, 4.62) in the last 12 months”. Moderate use of screens (4 h/day) was also associated with lower psychological well-being. Associations between screen time and lower psychological well-being were larger among adolescents than younger children.

Line chart showing Singapore's Total Fertility Rate 1957-2001

Figure 1: T1 represented screen time before the lockdowns and T2 represented the screen time after lockdowns

Healthcare workers

Fear of infection & other concerns

Undoubtedly, healthcare workers (HCWs) experienced the closest, prolonged contact with COVID-19 patients. An article published on the website of the Center for Evidence-Based Medicine suggests that among 4,950 close contacts during quarantine, 129 cases (2.6%) were diagnosed, with eight being asymptomatic (6.2%), 49 mild (38%), and five (3.9%) severe to critical. The fear of infection was highlighted in a qualitative study by Cao et al. (2020), and brought up as a theme in free-text feedback in a cross sectional survey by Chung & Yeung. Ahmed et al. found that 87% of medical workers described a fear of being infected with COVID-19 from either a patient or a co-worker. As per Cai et al (2020), concerns for personal safety, for the safety of their families, and concerns for patient mortality were all important stress-triggering factors in the medical staff. Therefore, all these stressors result in significant levels of anxiety, depression, insomnia and distress. A study found that 89% of healthcare workers during this outbreak reported psychological disorders. While facing COVID-19, studies revealed a prevalence of depressive symptoms between 8.9-50.4% and anxiety rates between 14.5-44.6% reported by the BMC public health. Moreover, female medical workers, younger workers and front-line workers had greater fear and higher infection rates when compared to others.

Working conditions

Personal protective equipment (PPE) is worn by doctors, nurses and other healthcare workers to minimize the risk of infection for staff and other patients, however PPE is quite uncomfortable and annoying to put on and to take off. The HCWs continue to care for patients despite the uncomfortable PPE (Hoernke et al). Along with the uncomfortable PPE, HCWs also work many long shifts. The extra workload leads to burnout (Leo et al).  Many healthcare workers are exhausted because of the working conditions and work overload. 


The Impoverished

Food resources

The COVID-19 outbreak brought new challenges related to food supply shortages, increased food prices, and a general cost-of-living rise. Poverty and food insecurity affect people in all regions of the world to different extents according to the availability of and access to tools that guarantee the survival of the population. Increased poverty and food insecurity is expected due to the complexity of generating income in more vulnerable segments of the population, especially those who don’t have a stable job and live on the streets. Both food insecurity and hunger are associated with depression, anxiety and suicidal ideation and attempts.  The relationship between hunger and poor mental health strengthened during lockdowns. Of those individuals who experienced hunger “every day in the past 7 days”, two-thirds (67%) screened positive for depressive symptoms. Malnutrition and moderate and severe food insecurity not only affects a person’s mental health, but can also weaken the body’s immune system. According to a health review paper published on the International Life Sciences Institute (ILSI) website titled “A call to action to address COVID-19-induced global food insecurity to prevent hunger, malnutrition, and eating pathology”, coordinated preparedness is the single most important action that can be taken at the local, community, government, and global levels. 

Face masks

Face masks are a very important part in stopping the spread of COVID-19, however they have been in high demand during the pandemic and have become increasingly expensive. This means that those living paycheck to paycheck or being supported by benefits may not have been able to afford face masks throughout the pandemic (Tucho and Kumsa). This puts them at higher risk of catching COVID-19 as they will be exposed to the virus more frequently without adequate protection. This is worsened by the need to also pay for basic living expenses, the cost of which may be too great for those without financial security.

Lack of healthcare access

Those unable to afford unexpected expenses are also more likely to seek medical assistance at a more advanced stage of illness. This often leads to worse health outcomes. They are also likely to be living in crowded homes with multiple occupants. This increases the risk of infection for the people living there. Such conditions may also not allow access to clean water and soap, both of which are needed for washing hands to stop the spread of the virus. Likewise, those who are the least financially well off often work more manual or customer-facing jobs that do not allow them to work from home, for example jobs in warehouses, supermarkets etc. This means that if they want to isolate, they may have to quit their jobs, which would put them in even greater financial distress (Patel et al). 



In conclusion, in this review we have looked at all the possible social, educational and economic factors that affect the mental health of the three most vulnerable groups of people during the COVID-19 pandemic. We have also discussed some brief and possible improvements we can make to encourage a reduction in mental health problems during pandemics.

For adolescents and toddlers, we would encourage schools to carry out a personal, social, health and economic day focused on balancing screen time and green time of students. The government should also promote anti-addiction modes in entertainment apps, especially games.  There should be volunteering programmes in each community for helping to take care of toddlers and infants when parents are self-isolating. Setting up fundraising programmes for the impoverished and donating to relevant charities would likely help to relieve some of the burden brought about by pandemics.

The main limitation of this review is that there are many confounding factors that cause stress and poor mental health. There is no way to definitively know whether a certain factor will lead to a specific problem.


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