The Effectiveness of Face Masks in Preventing COVID-19 Transmission: A Systematic Review.

INTRODUCTION: Since the beginning of the COVID-19 pandemic, face masks have been among the cornerstones of COVID-19 prevention. Therefore, evaluating their preventive effects against COVID-19 is crucial. This review aimed to systematically search for the systematic review articles that explored the role of various types of face masks in preventing COVID-19. METHODS: We browsed the keywords of this study in the online databases of Scopus, Web of Science, PubMed, and Cochrane on 10th January 2023 and retrieved all the relevant systematic review articles. The records were downloaded into an Endnote file, and the duplicates were removed. A two-step screening process consisting of title/abstract and full-text screenings was conducted to select the most relevant articles. To ensure the validity and reliability of the results, this study adhered to the PRISMA protocol. RESULTS: A total of 28 systematic reviews were included in this review. Most studies found that face masks are beneficial against viral respiratory infections, such as COVID-19. Different types of masks were evaluated in included studies. It appeared that mask efficacy depends on the material, layers, fitting on the face and user compliance. N 95 respirator had maximum efficacy, especially when used continuously. CONCLUSION: Face masks have a beneficial effect against COVID-19. Home masks are less protective than surgical masks or N95 personal breathing masks. Besides, the use of masks may elicit a false sense of security in people, which may lead to poor hand hygiene and violation of social distancing. Therefore, the necessary training should be provided to the public to increase awareness and encourage the right practice of using the mask, emphasizing the preventive effects of washing hands, social distancing, and using a face mask against COVID-19.

Clinical and microbiological patterns in critically ill patients with catheter-associated UTI: A report from Iran.

INTRODUCTION: Catheter-associated urinary tract infections (CAUTIs) are among the most common nosocomial infections with different clinical and microbiological characteristics. We studied these characteristics in critically ill patients. METHODOLOGY: This research was a cross-sectional study conducted on intensive care unit (ICU) patients with CAUTI. Patients' demographic and clinical information and laboratory data, including causative microorganisms and antibiotic susceptibility tests, were recorded and analyzed. Finally, the differences between the patients who survived and died were compared. RESULTS: After reviewing 353 ICU cases, 80 patients with CAUTI were finally included in the study. The mean age was 55.9 ± 19.1 years, 43.7% were male and 56.3% were female. The mean length of infection development since hospitalisation and hospital stay were 14.7 (3-90) and 27.8 (5-98) days, respectively. The most common symptom was fever (80%). The microbiological identification showed that the most isolated microorganisms were Multidrug-resistant (MDR) Enterobacteriaceae (75%), Pseudomonas aeruginosa (8.8%), Gram-positive uropathogens (8.8%) and Acinetobacter baumannii (5%). Fifteen patients (18.8%) died among whom infections with A. baumannii (75%) and P. aeruginosa (57.1%) were associated with more death (p = 0.005). CONCLUSIONS: Although A. baumannii and P. aeruginosa can be the most important pathogens for death, MDR Enterobacteriaceae are still a serious concern as causes of CAUTIs.

Effects of Smoking on COVID-19 Management and Mortality: An Umbrella Review.

Introduction: Smoking status appears to lead to a poor prognosis in COVID-19 patients. However, findings from the studies conducted on this topic have not been consistent, and further exploration is required. Methods: The objective of this umbrella review was to examine the effects of smoking on COVID-19 management and mortality. Online databases that included PubMed, Embase, Scopus, and Web of Science were searched using relevant keywords up to July 27, 2022. Articles were restricted to the English language, and the PRISMA protocol was followed. Results: A total of 27 systematic reviews, published from 2020 to 2022, were included. Individual studies included in the systematic reviews ranged from 8 to 186, with various population sizes. The consensus from the majority of systematic reviews was that COVID-19 smoker patients experience greater disease severity, disease progression, hospitalization rate, hospital admission duration, mechanical ventilation, ICU admission, and mortality rate. Conclusions: COVID-19 patients with a history of smoking (current and former) are vulnerable to adverse hospital outcomes and worse COVID-19 progression. Effective preventive and supportive approaches are required to decrease the risk of COVID-19 morbidity and mortality in patients with a history of smoking.

SARS-CoV-2 Infection and Severity in Patients with Hematologic Malignancies: A Systematic Review.

INTRODUCTION: Earlier reports described the possibility of higher SARS-CoV-2 infection and severity in patients with hematological malignancies. Given the importance and incidence of these malignancies, we aimed to systematically review SARS-CoV-2 infection and severity in patients with hematologic cancers. METHODS: We retrieved the relevant records by searching the keywords in online databases of PubMed, Web of Science, Cochrane, and Scopus on December 31st , 2021. A two-step screening; title/abstract and full-text screening, was employed to select the eligible studies. These eligible studies entered the final qualitative analysis. The study is adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of the results. RESULTS: Forty studies concerning different hematologic malignancies and the effect of COVID-19 infection on them were included in the final analysis. The findings showed that in general, the prevalence of SARS-CoV-2 infection and the severity of the disease are often higher in hematologic malignancies and the patients could experience higher morbidity and mortality compared to general populations. CONCLUSION: It appeared that individuals with hematologic malignancies are more vulnerable to COVID-19 infection and they experience more severe disease with higher mortality rates. The presence of other comorbidities could also deteriorate this situation. Further Investigation is recommended to evaluate the outcome of COVID-19 infection in different subtypes of hematologic malignancies.

Late Complications of COVID-19; An Umbrella Review on Current Systematic Reviews.

Introduction: Several clinical manifestations have been discovered for COVID-19 since the emergence of SARS-CoV-2, which can be classified into early, medium, and long-term complications. However, late complications can be present after recovery from acute COVID-19 illness. The present study aims to comprehensively review the available evidence of late complications related to COVID-19. Method: A search was conducted, using keywords, through electronic databases, which included Scopus, Web of Science, PubMed, and Embase up to August 29, 2022. Study selection was performed according to a strict inclusion and exclusion criteria. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) checklist was followed, and studies were appraised using the National Institute of Health (NIH) quality assessment and risk of bias tool. Results: In total, 50 studies were included, and nine distinct COVID-19 late complication categories were identified. A review of these studies revealed that neurologic and psychiatric (n=41), respiratory (n=27), musculoskeletal and rheumatologic (n=22), cardiovascular (n=9), and hepatic and gastrointestinal (n=6) complications were the most prevalent complications of long COVID-19. Conclusion: Almost all human body systems are affected by late complications of COVID-19 with different severity and prevalence. Fatigue and some other neuropsychiatric symptoms are the most common late complications among long COVID-19 patients. Respiratory symptoms including dyspnea (during exercise), cough, and chest tightness were the next most prevalent long-term complications of COVID-19. Since these complications are persistent and late, being aware of the signs and symptoms is essential for the healthcare providers and patients.

The comparison of clinical, laboratory, and radiological findings in immunocompromised and immunocompetent patients with COVID‐19: A case‐control study

Background Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) causes coronavirus disease 2019 (COVID‐19) with significant morbidity and mortality. We reported and compared the clinical and para‐clinical findings of immunocompromised and immunocompetent COVID‐19 patients in a case‐control study at the Imam Khomeini hospital in Tehran, Iran. Methods In this study, 107 immunocompromised COVID‐19 patients were recruited as the case group, and 107 immunocompetent COVID‐19 patients as the control group. The participants were matched based on age and sex. The patients' information was retrieved from the hospital records in an information sheet. Associations between clinical and para‐clinical findings with the immune status were assessed using bivariate and multivariate analyses. Results The initial pulse rate and recovery time were significantly higher in immunocompromised patients (p < .05). Myalgia, nausea/vomiting, loss of appetite, headache, and dizziness were more frequently reported by the control group (p < .05). Regarding the prescribed medications' duration, Sofosbovir was used longer in the case group, while Ribavirin was used longer in the control groups (p < .05). The most common complication in the case group was acute respiratory distress syndrome, although no major complications were observed in the control group. According to the multivariate analysis, recovery time and Lopinavir/Ritonavir (Kaletra) prescription were significantly higher in the immunocompromised compared to the immunocompetent group. Conclusion Recovery time was significantly longer in the immunocompromised compared to the immunocompetent group, which emphasizes the necessity of prolonged care in these high‐risk patients. Also, it is recommended to investigate the effect of novel therapeutic interventions to reduce the recovery time in addition to improving the prognosis of immunodeficient patients with COVID‐19. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) causes coronavirus disease 2019 (COVID‐19) with significant morbidity and mortality. We reported and compared the clinical and para‐clinical findings of immunocompromised and immunocompetent COVID‐19 patients in a case‐control study at the Imam Khomeini hospital in Tehran, Iran. A total of 107 immunocompromised COVID patients as the case group and 107 immunocompetent COVID patients as the control group was recruited in the study. The participants were matched based on age and sex. The patients' information was retrieved from the hospital records in an information sheet. Associations between clinical and para‐clinical findings with the immune status were assessed using bivariate and multivariate analyses. The clinical trial registration number is not applicable. The initial pulse rate and recovery time were significantly higher in immunocompromised patients (p < .05). Myalgia, nausea/vomiting, loss of appetite, headache, and vertigo were more frequently reported by the control group (p < .05). In terms of the duration of prescribed medications, Sofosbovir time was longer in the case group;while Ribavirin time was longer in the control groups (p < .05). The most common complication in the case group was acute respiratory distress syndrome although no major complications were observed in the control group. In the multivariate analysis, recovery time and Kaletra prescription were significantly higher in immunocompromised compared to the immunocompetent group. Recovery time was significantly higher in the immunocompromised compared to the immunocompetent group. This informs the current practice of dominant COVID‐19 clinical course in immunocompromised patients and communicates the related implications.

Telemedicine technologies and applications in the era of COVID-19 pandemic: A systematic review.

INTRODUCTION: Telemedicine services saw substantial surges in their use during the COVID-19 pandemic due to the lockdowns and characteristics of the pandemic. Therefore, the authors aimed to systematically review the telemedicine services provided during the COVID-19 pandemic and their potential applications. METHODS: The authors searched PubMed, Scopus, and Cochrane databases on September 14, 2021. Then, the retrieved records underwent two-step title/abstract and full-text screening processes, and the eligible articles were included for qualitative synthesis. RESULTS: The review of studies demonstrated that the telephone is listed 38 times, making it the most common technology used in telemedicine. Video conferencing is also mentioned in 29 articles, as well as other technologies: Mobile-health (n = 15), Virtual reality (n = 7). According to the findings of the present study, Tele-follow-up (n = 24), Tele-consulting (n = 20), Virtual visits (20), and Tele-monitoring (n = 18) were the most widely used telemedicine applications. CONCLUSION: Telemedicine has been an effective approach to COVID-19 management. Telemedicine technology is going to play a key role in the future of health medicine, patient consultation, and many other extended applications of health care in remote rural locations.

Post-Exposure Prophylaxis for COVID-19: A Systematic Review.

INTRODUCTION: SARS-CoV-2 cause pneumonia can spread across the lung and lead to acute respiratory distress syndrome (ARDS) in severe cases. Post-exposure prophylaxis has shown great potential to prevent the transmission of some viral infections; however, such results for COVID-19 are still inconclusive. METHODS: Therefore, the aim of this study was to systematically review the resources that utilized postexposure prophylaxis (PEP) for COVID-19 and the possible clinical benefits of such drugs. An organized search of relevant literature was done using the keywords and search queries on public databases of Cochrane, PubMed, Web of Science and Scopus from December 2019 to August 23, 2021. Original resources that had the inclusion criteria were included after two-phase title/abstract and full-text screenings. This review adhered to the Preferred Reporting Items for Systematic Reviews and MetaAnalysis (PRISMA) statement. RESULTS: Out of 841 retrieved records 17 resources were appropriate to include in the systematic review. Hydroxychloroquine with a daily dose of 400-800 mg and a duration of 5-14 days was the most frequently used agent for PEP. Chloroquine was recommended to use to control treatment in patients with mild to severe COVID-19 pneumonia. Other agents like Lopinavir-ritonavir (LPV/r), angiotensinconverting enzyme inhibitors (ACEIs), Angiotensin receptor blockers (ARBs), Vitamin D, arbidol, thymosin drugs, and Xin guan no.1 (XG.1, a Chinese formula medicine) have also been applied in some studies. CONCLUSION: Current evidence demonstrated no established clinical benefits of any drug as PEP in individuals with COVID-19. However, scarce indication occurs for the beneficial effects of some agents, but more studies are needed to explore such effects.

The comparison of clinical, laboratory, and radiological findings in immunocompromised and immunocompetent patients with COVID-19: A case-control study.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) with significant morbidity and mortality. We reported and compared the clinical and para-clinical findings of immunocompromised and immunocompetent COVID-19 patients in a case-control study at the Imam Khomeini hospital in Tehran, Iran. METHODS: In this study, 107 immunocompromised COVID-19 patients were recruited as the case group, and 107 immunocompetent COVID-19 patients as the control group. The participants were matched based on age and sex. The patients' information was retrieved from the hospital records in an information sheet. Associations between clinical and para-clinical findings with the immune status were assessed using bivariate and multivariate analyses. RESULTS: The initial pulse rate and recovery time were significantly higher in immunocompromised patients (p < .05). Myalgia, nausea/vomiting, loss of appetite, headache, and dizziness were more frequently reported by the control group (p < .05). Regarding the prescribed medications' duration, Sofosbovir was used longer in the case group, while Ribavirin was used longer in the control groups (p < .05). The most common complication in the case group was acute respiratory distress syndrome, although no major complications were observed in the control group. According to the multivariate analysis, recovery time and Lopinavir/Ritonavir (Kaletra) prescription were significantly higher in the immunocompromised compared to the immunocompetent group. CONCLUSION: Recovery time was significantly longer in the immunocompromised compared to the immunocompetent group, which emphasizes the necessity of prolonged care in these high-risk patients. Also, it is recommended to investigate the effect of novel therapeutic interventions to reduce the recovery time in addition to improving the prognosis of immunodeficient patients with COVID-19.

Is There a Role for Hyperbaric Oxygen Therapy in Reducing Long-Term COVID-19 Sequelae?

The COVID-19 pandemic has plagued our society for approximately three years [...].

Minimum infective dose of severe acute respiratory syndrome coronavirus 2 based on the current evidence: A systematic review.

Objective: Understanding the minimum infective dose is significant for risk assessment in the performance of suitable infection control strategies in healthcare centers. However, the literature lacks strong evidence regarding this value for severe acute respiratory syndrome coronavirus 2. Therefore, the aim of this study was to investigate the minimum infectious dose of coronavirus disease 2019. Methods: We searched the databases of PubMed, Scopus, Web of Science, and Cochrane and retrieved all the relevant literature by 25 July 2021. The records were downloaded into the EndNote software and underwent title/abstract and full-text screenings. A summary of included studies was organized into tables for further analysis, interpretation, and drafting of the results. Results: Nineteen studies including the laboratory data on human and animal hosts were selected based on the eligibility criteria. All the literature reported on the infective dose, particularly in humans. The main methods for measurement of infection were through tissue culture infectious dose (TCID50) and counting plaque-forming units. The range of minimum infective was 1.26-7 × 106.25 PFU. Conclusion: In this study, we have presented a range of minimum infective doses in humans and various animal species. Such numbers can possibly vary between the individuals based on numerous demographic, immunologic, or other factors.

Complications of COVID-19 Vaccines during Pregnancy; a Systematic Review.

Introduction: Rare serious complications have been documented after COVID-19 vaccination as clinical research proceeded and new target populations, such as children and pregnant women, were included. In this study, we attempted to review the literature relevant to pregnancy complications and maternal outcomes of COVID-19 immunization in pregnant women. . Methods: We searched the databases of PubMed, Scopus, Cochrane, and Web of Science on 31 August 2022. The records were downloaded and underwent a two-step screening; 1) title/abstract and then 2) full-text screening to identify the eligible studies. We included English original studies that evaluated the adverse effects of COVID-19 vaccines during pregnancy. Information such as the type of study, geographical location, type of vaccine injected, gestational age, maternal underlying diseases, and complications following the vaccination were extracted into pre-designed tables. Results: According to the findings of included studies, in most of them vaccination had a positive impact and no negative effects were observed. Also, no medical history was reported in 11 articles, and pregnant women had no underlying diseases. Some serious adverse events were reported after vaccination, including miscarriage, paresthesia, uterine contraction, vaginal bleeding, preterm birth, major congenital anomalies, intrauterine growth restriction, and seizure. . Conclusion: Because of limited data availability and the cross-sectional design of most studies, we could neither infer causation between vaccines and incidence of adverse effects nor comment with certainty about any possible adverse outcome of COVID-19 vaccines in vaccinated pregnant women. Consequently, more longitudinal and experimental studies are needed to define the exact adverse effects of COVID-19 vaccines in pregnant women.

Gut microbiota and COVID-19: A systematic review.

Background and Aims: Alteration in humans' gut microbiota was reported in patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The gut and upper respiratory tract (URT) microbiota harbor a dynamic and complex population of microorganisms and have strong interaction with host immune system homeostasis. However, our knowledge about microbiota and its association with SARS-CoV-2 is still limited. We aimed to systematically review the effects of gut microbiota on the SARS-CoV-2 infection and its severity and the impact that SARS-CoV-2 could have on the gut microbiota. Methods: We searched the keywords in the online databases of Web of Science, Scopus, PubMed, and Cochrane on December 31, 2021. After duplicate removal, we performed the screening process in two stages; title/abstract and then full-text screening. The data of the eligible studies were extracted into a pre-designed word table. This study adhered to the PRISMA checklist and Newcastle-Ottawa Scale Bias Assessment tool. Results: Sixty-three publications were included in this review. Our study shows that among COVID-19 patients, particularly moderate to severe cases, the gut and lung microbiota was different compared to healthy individuals. In addition, the severity, and viral load of COVID-19 disease would probably also be influenced by the gut, and lung microbiota's composition. Conclusion: Our study concludes that there was a significant difference in the composition of the URT, and gut microbiota in COVID-19 patients compared to the general healthy individuals, with an increase in opportunistic pathogens. Further, research is needed to investigate the probable bidirectional association of COVID-19 and human microbiome.

Estimating Methods of the Undetected Infections in the COVID-19 Outbreak: A Systematic Review.

INTRODUCTION: The accurate number of COVID-19 cases is essential knowledge to control an epidemic. Currently, one of the most important obstacles in estimating the exact number of COVID-19 patients is the absence of typical clinical symptoms in a large number of people, called asymptomatic infections. In this systematic review, we included and evaluated the studies mainly focusing on the prediction of undetected COVID-19 incidence and mortality rates as well as the reproduction numbers, utilizing various mathematical models. METHODS: This systematic review aims to investigate the estimating methods of undetected infections in the COVID-19 outbreak. Databases of PubMed, Web of Science, Scopus, Cochrane, and Embase, were searched for a combination of keywords. Applying the inclusion/exclusion criteria, all retrieved English literature by April 7, 2022, were reviewed for data extraction through a two-step screening process; first, titles/abstracts, and then full-text. This study is consistent with the PRISMA checklist. RESULTS: In this study, 61 documents were retrieved using a systematic search strategy. After an initial review of retrieved articles, 6 articles were excluded and the remaining 55 articles met the inclusion criteria and were included in the final review. Most of the studies used mathematical models to estimate the number of underreported asymptomatic infected cases, assessing incidence and prevalence rates more precisely. The spread of COVID-19 has been investigated using various mathematical models. The output statistics were compared with official statistics obtained from different countries. Although the number of reported patients was lower than the estimated numbers, it appeared that the mathematical calculations could be a useful measure to predict pandemics and proper planning. CONCLUSION: In conclusion, our study demonstrates the effectiveness of mathematical models in unraveling the true burden of the COVID-19 pandemic in terms of more precise, and accurate infection and mortality rates, and reproduction numbers, thus, statistical mathematical modeling could be an effective tool for measuring the detrimental global burden of pandemic infections. Additionally, they could be a really useful method for future pandemics and would assist the healthcare and public health systems with more accurate and valid information.

The Impact of COVID-19 Pandemic on the Levels of Physical Activity: A Systematic Review.

INTRODUCTION: Earlier studies demonstrated a decreased level of physical activity (PA) during the COVID-19 pandemic. Therefore, we aimed to systematically review the relevant studies among various age groups and explore the impact on physical and mental health. METHODS: We searched and retrieved all relevant articles using the keywords on the online databases of PubMed, Scopus, and Cochrane from the start of the pandemic until May 3rd, 2021. A two-phase screening process of identified records was carried out to shortlist the most relevant studies. First, the studies were evaluated based on their title/abstract, and then the full-text of included studies was thoroughly read. The eligible studies based on the eligibility criteria were included in this review. RESULTS: A total of 57 studies were included based on the eligibility criteria. Lockdowns and infection with SARS-CoV-2 have led to a decreased level of PA in the general population compared to the prepandemic era. Men had significantly less PA compared to women in some studies, probably due to higher pre-pandemic PA. The level of PA among those with chronic diseases also significantly diminished, putting them at a higher risk of cardiovascular incidents. Sedentary lifestyles have dominated people's life, including adolescents and university students. The increased levels of mental health issues, such as depression, anxiety, and occupational stress, have been suggested to contribute to the decreased PA. On the other hand, the decreased PA appeared to lead to more mental health issues. Fortunately, the decreasing trend of PA seemed to taper towards the end of the quarantines. CONCLUSION: Overall, the COVID-19 pandemic and subsequent quarantines reduced PA among all age groups and both sexes and had detrimental effects on people's physical and mental health. We suggest countries implement strategies to alleviate restrictions and encourage people to exercise in safe environments and prepare healthy routines for themselves.

Evaluating the effects of air disinfectants in decontamination of COVID-19 aerosols.

Introduction: Airborne transmission is the most  crucial mode of COVID-19 transmission. Therefore, disinfecting the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) aerosols float can have important implications in limiting COVID-19 transmission. Herein, we aimed to review the studies that utilized various disinfectants to decontaminate and inactivate the SARS-CoV-2 aerosols. Methods: This study was a review that studied related articles published between December 1, 2019 and August 23, 2022. We searched the online databases of PubMed, Scopus, Web of Science, Cochrane, on August 23, 2021. The studies were downloaded into the EndNote software, duplicates were removed, and then the studies were screened based on the inclusion/exclusion criteria. The screening process involved two steps; first, the studies were screened based on their title and abstract and then their full texts. The included studies were used for the qualitative analysis. Results: From 664 retrieved records, only 31 met the inclusion criteria and were included in the final qualitative analysis. Various materials like Ozone, H2O2, alcohol, and TiO2 and methods like heating and using Ultraviolet were described in these studies to disinfect places contaminated by COVID-19. It appeared that the efficacy of these disinfectants varies considerably depending on the situation, time, and ultimately their mode of application. Conclusion: Following reliable protocols in combination with the proper selection of disinfectant agents for each purpose would serve to achieve desired elimination of the SARS-CoV-2 transmission.

The impacts of COVID-19 pandemic on service delivery and treatment outcomes in people living with HIV: a systematic review.

INTRODUCTION: The COVID-19 epidemic and various control and mitigation measures to combat the widespread outbreak of the disease may affect other parts of health care systems. There is a concern that the COVID-19 pandemic could disrupt HIV services. Therefore, this study aimed to systematically evaluate the effect of the COVID-19 pandemic on service delivery and treatment outcomes in people with HIV. METHODS: In this study, a systematic search was conducted using the keywords in the online databases including Scopus, PubMed, Web of Science, and Cochrane databases. The retrieved articles underwent a two-step title/abstract and full-text review process, and the eligible papers were selected and included in the qualitative synthesis. RESULT: We selected 16 studies out of 529 retrieved records that met the inclusion criteria for this review. Study populations of the selected studies were either HIV-positive patients or HIV clinics and healthcare providers. Most studies were focused on adhering to and obtaining medication and attending clinical appointments and their decrement during the pandemic. Other aspects of HIV care (alternative healthcare settings, viral suppression, psychological care, etc.) were discussed to a lesser extent by the included studies. CONCLUSION: Interruption in in-person visits and medical follow-up services, loss of adherence to treatment, and subsequent increase in mortality due to the COVID-19 pandemic complications in PLHIV have led to growing concerns. Other challenges were psychological disorders such as anxiety and depression, an increase in substance abuse, and a rise in experienced stigma and discrimination. However, the use of telemedicine in some countries helps to alleviate the situation to some extent and is recommended in similar settings in the future.

COVID-19 Vaccines' Protection Over Time and the Need for Booster Doses; a Systematic Review.

Introduction: Controversies existed regarding the duration of COVID-19 vaccines' protection and whether receiving the usual vaccine doses would be sufficient for long-term immunity. Therefore, we aimed to systematically review the studies regarding the COVID-19 vaccines' protection three months after getting fully vaccinated and assess the need for vaccine booster doses. Methods: The relevant literature was searched using a combination of keywords on the online databases of PubMed, Scopus, Web of Science, and Cochrane on September 17th, 2021. The records were downloaded and the duplicates were removed. Then, the records were evaluated in a two-step process, consisting of title/abstract and full-text screening processes, and the eligible records were selected for the qualitative synthesis. We only included original studies that evaluated the efficacy and immunity of COVID-19 vaccines three months after full vaccination. This review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement to ensure the reliability of results. Results: Out of the 797 retrieved records, 12 studies were included, 10 on mRNA-based vaccines and two on inactivated vaccines. The majority of included studies observed acceptable antibody titers in most of the participants even after 6 months; however,it appeared that the titers could also decrease in a considerable portion of people. Due to the reduction in antibody titers and vaccine protection, several studies suggested administering the booster dose, especially for older patients and those with underlying conditions, such as patients with immunodeficiencies. Conclusion: Studies indicated that vaccine immunity decreases over time, making people more susceptible to contracting the disease. Besides, new variants are emerging, and the omicron variant is continuing to spread and escape from the immune system, indicating the importance of a booster dose.