This study showed that Palestinian refugees in Jerash camp live in conditions that could be considered poor. The refugees have low educational levels, a high smoking prevalence, and an extremely high unemployment rate, as well as a lack of health insurance coverage. Thus, most of refugees use only non-profit healthcare centers owned and operated by the government agencies or non-government organizations (NGOs). These factors may underlie the low COVID-19 testing rate, which is more likely contributing to the low rate of the reported cases among the refugees. Interestingly, refugees who were infected with COVID-19 tend to experience symptoms at a lower severity level (self-reported). Furthermore, the most frequently reported symptoms were general fatigue, headache, fever, anosmia and/or ageusia, and cough, respectively, with no significant differences between refugees and citizens. These symptoms were also reported in many previous studies from different regions [35,36,37].
Interestingly, the results obtained in this study demonstrated that the perceptions and experiences of COVID-19 vaccination were different between refugees and citizens. Although refugees were less likely than citizens to believe that COVID-19 vaccines are safe in the long-term and that these vaccines are effective in combating the pandemic, COVID-19 vaccine hesitancy was significantly lower among refugees. Despite a higher percentage of refugees had refused to receive a vaccine, other than a COVID-19 vaccine, in the past. The final logistic regression model showed that the belief that the long-term safety of COVID-19 vaccines among all participants was affected by gender, age and smoking, while the belief that COVID-19 vaccines are effective and help in combating the pandemic was affected by age and level of education.
The WHO defined vaccine hesitancy as a reluctance to be vaccinated despite the availability of the vaccines, and the organization in 2019 designated hesitancy to get vaccinated as one of the ten threats that affect the global health [38, 39]. In this study, the low vaccine hesitancy among refugees could be associated with the low level of education among them. The final logistic regression model showed that COVID-19 vaccine hesitancy among all participants was affected by gender, age and level of education. As reported in recent studies, people with a lower education level showed significantly greater willingness to receive a COVID-19 vaccine, while those with a higher education level expressed greater vaccine hesitancy [40, 41]. Chen and associates  have also reported significant negative correlations between both participants’ monthly income and age with their willing to be vaccinated against COVID-19.
The low vaccine hesitancy among refugees could also be associated with the variation in the sources of information about the COVID-19 vaccines between refugees and citizens. For example, scientific and medical websites were the main source of information among citizens, while higher percentages of refugees rely on information from social media platforms and from their relatives and friends. In another study, Theocharis and associates  indicated a significant role of some social media platforms in the spread and upswing of COVID-19 conspiracy theories. As shown in a study by Bullock and associates , vaccine hesitancy can be driven by conspiracy theories, fear, doubt, distrust of scientific expertise, and lack of information. Furthermore, the final logistic regression model showed that, among all the participants, the conspiracy theory which says that SARS-CoV-2 is a biological weapon developed at a lab as an artificial creation was affected by age and education level.
Moreover, difficulties or restrictions upon the registration to receive a COVID-19 vaccine were more common among refugees. Refugee-hosting countries may experience a range of legal and administrative barriers to immunization services, including real, restricted or perceived lack of entitlement to free COVID-19 vaccines or health care in general, and a lack of safe and trusted access points . The final logistic regression model showed that facing difficulties or restrictions upon the registration to receive a COVID-19 vaccine among all participants was affected by residency status (refugee or citizen) and gender. Therefore, the percentages of partially- and fully-vaccinated refugees were significantly lower compared to citizens in this study, and a less percentage of vaccinated refugees have advised other people to get vaccinated against COVID-19.
These findings were expected with the limited education and healthcare facilities, as well as the high rate of poverty in Jerash camp . A previous study has shown that Palestinian refugees in Jordan have a lower health-related quality of life compared to Jordanian citizens . However, there are 24 primary healthcare centers run by the UNRWA in the Palestinian refugee camps in Jordan . The United Nations High Commissioner for Refugees (UNHCR), supported by volunteers from the refugees themselves, has provided the refugees with a small package to cover their transportation to the nearest vaccination center. By correcting all the misinformation about the COVID-19 origin and vaccines, a group of these volunteers is helping in fighting against the rumors that refugees believed in and made them hesitant to take a COVID-19 vaccine .
The distribution of different types of COVID-19 vaccines (i.e., AstraZeneca, Pfizer–BioNTech and Sinopharm) were similar in refugees and citizens. The most frequently reported post-vaccination adverse effects among all participants were general fatigue, joint pain and myalgia, injection site reactions, headache and fever, respectively. These adverse effects were in a line with that previously reported [28, 48, 49]. More specifically, in a multinational study involving more than 10,000 participants from all Arab countries, including Jordan and Palestine, these adverse effects were also most frequently reported . Vaccine adverse effects are normal signs indicating the immune system is responding to promote protection to the body against the virus. As observed in most vaccines, adverse effects of COVID-19 vaccines range from mild to moderate flu-like symptoms. According to the CDC, the most common adverse effects following COVID-19 vaccination are injection site pain, redness and swelling, as well as fatigue, headache, muscle pain, chills, fever and nausea . Previous studies showed that adverse effects of the COVID-19 vaccine were observed more in individuals who received the Pfizer and the AstraZeneca vaccines compared to those who received the Sinopharm vaccine [28, 29, 51]. Although, our study showed no significant differences in the frequencies of adverse effects based on the type of COVID-19 vaccine or the number of doses. In the present study, the proportion of refugees who experienced post-vaccination adverse effects was lower and there were significant differences between the frequency of some adverse effects between refugees and citizens. The refugees were less likely to experience fatigue, joint pan and myalgia, injection site reactions, nausea, abdominal pain and diarrhea following COVID-19 vaccination. Furthermore, refugees were more likely to face the post-vaccination adverse effects after 24 h and above of vaccination.
COVID-19 vaccine adverse effects are expected to disappear after a few days from their appearance. Furthermore, they may not be experienced by some people and this is attributed to the way each immune system differs in its response . There was no significant difference in the duration of these adverse effects between refugees and citizens. Interestingly, these findings might be consistent with a known theory that indicates people who are mostly habituated to living in poverty with the lesser hygienic conditions and inadequate or restricted access to health services could have naturally acquired better immunity and more resilient to infection .
In this study, there were a few additional questions to assess the refugees’ attitudes towards COVID-19 and its related safety and public measures. The percentage of refugees who believe that medicinal plants (e.g., garlic and ginger) and foods (e.g., honey) can be effective in combating COVID-19 was significantly higher. This is not unique in this study, since different population from different countries including China, India, Morocco, Thailand, Bolivia, Nepal and Peru were found to consuming different medicinal plants in order to fight COVID-19 infection [54,55,56,57,58,59,60]. Interestingly, the WHO demonstrated that 80% of the population reside in developing countries use traditional medicine as their main source of medical treatment . Furthermore, the Arab World has been characterized through generations by an abundant inventory of medicinal plant usage . In the 21st century, traditional medicinal plants are still commonly used, especially in communities with high poverty rates like refugee camps, as an affordable healthcare regime. In fact, consuming medicinal plants might be useful for the health and boosting the immunity , but it cannot be an alternative approach to combat an extreme global pandemic like COVID-19.
A significantly greater proportion of participants who believe that vaccinated people no longer need to wear face masks, practice social distancing and follow proper prevention hygiene was reported among refugees. The personal commitment to wearing a face mask and not shaking hands was significantly lower among refugees. The participants were also asked about their observations regarding the commitment of restaurants and cafes (in their places of residence) to the government rules during the different phases of the COVID-19 lockdown. There was a significant difference between refugees and citizens indicating a lesser level of commitment by the restaurants and cafes in the refugee camp. Again, all these findings were expected and attributed to the refugees’ low educational levels and the lower level of awareness of COVID-19 in the camp. A study conducted in Germany showed that highly educated persons were more worried about the COVID-19 than their peers with lower levels of education . Since it is well-known that health literacy promotes the commitment of individuals to follow public health measures to prevent infectious diseases and cope with pandemics, Naveed and Shaukat  have conducted a study to assess this theory among university students in Pakistan. They reported a positive association indicating that greater health literacy promoted COVID-19 awareness and protective behaviors of participants.
Surprisingly, unlike citizens, a significant percentage of refugees believe that public and private institutions and departments were probably following social distancing rules and other COVID-19 public health measures. We were unable to explain this difference; but it might be because the refugees from Jerash camp have limited access to such official institutions and departments compared to citizens.
Indeed, cross-sectional studies are often conducted on a single population, and comparisons of the prevalence and incidence rates are made with the normal (control) groups in the literature. In the present study, we decided to conduct a comparative cross-sectional study on refugees and citizens because we needed data on the same parameters and questions that we included in the survey tool for the refugees. No study had yet addressed all of the issues we assessed among refugees, and the results of related previous studies were inconsistent for some parameters. Additionally, we have to mention that the effects of the various vaccines and people’s attitudes toward them might fluctuate drastically depending on a variety of other conditions.
The findings of controlling for confounding factors suggest two crucial points. First, depending on place of residence, most of the COVID-19 symptoms and post-COVID-19 vaccination adverse effects differ significantly. Second, if confounding variables like age, gender, and education level are not carefully controlled, they may obscure this effect. These findings strongly suggest that not only attitudes and perceptions, but also pathological and physiological symptoms of the COVID-19 infection and vaccination, may vary between minority groups and the general population. These variations might be explained by variations in immunity and health. Furthermore, these characteristics are challenging to study in such studies, especially given that refugees are reluctant to share their financial, insurance and other information.
On the other hand, recent two years have witnessed a runaway increase in the involvement of promising machine learning (ML) approaches that contribute to the global efforts for tackling the COVID‑19 pandemic . Interestingly, ML algorithms with different data models are widely used for predicting several properties and parameters related to COVID-19, including mortality rate, prevalence and severity of symptoms, incubation period, transmission routes, and control strategies [66, 67]. In the current observational study, the logistic regression model was used only to identify the significant factors associated with COVID-19 parameters. While future studies may also incorporate such advance models into large-scale, multicenter surveys to investigate the appropriate prevention and control strategies with minimum costs, and to ensure the normal operations of human society in refugee camps, not just in Jordan but also abroad.
The findings of this study will be of particular interest to researchers, government sectors and NGOs focused on improving the quality of life among refugees. This study will encourage for further exploration of health needs of refugees, especially those who are hosted in camps located poorer countries. Future studies that emphasis on the importance of equal access to quality education, social support and healthcare services for refugees are necessary to develop a more rigorous and systematic understanding of refugees’ needs. Furthermore, challenges facing refugees and international, national, or private agencies that work in refugee camps during and following the COVID-19 pandemic should be studied. Such studies can help to overcome these challenges, and thus strengthen pandemic preparedness and response systems in refugee camps.
In particular, as the leading agency that provides education, health and other services to Palestinian refugees in the Near East, UNRWA would benefit from the findings of this study to address the refugee challenges arising from the COVID-19 pandemic in Jerash camp. UNRWA may also be in a position to collaborate with local researchers to carry out multiple specialized studies to improve its programs in refugee camps for escaping the era of pandemics.
In closing, this study has some limitations including the inability to study the factors that associated with the acceptance of COVID-19 vaccines among the refugees such as source of information and the role of the social media which can play a significant role in spreading a negative information about COVID-19 vaccination. Further, the relevant data from previous research studies were scarce which hardening the discussion and to find the accurate justification of some results. However, this is the first study assessed the experiences and perceptions of COVID-19 infection and vaccination among refugees which prove that the findings of this study might help government policy-makers and NGOs to plan for better healthcare services, health literacy and awareness programs in Jerash camp and other refugee camps in Jordan. This study could be of interest to these parties as it may help in learning lessons from the COVID-19 pandemic which is the first global pandemic the refugees in Jordan have experienced, while the national and global health systems are suffering under immense and exceptional pressures.