Dynamic Interplay Between Microbiota and Mucosal Immunity in Early Shaping of Asthma and its Implication for the COVID-19 Pandemic

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.

Physicians' Understanding of the Role of the Microbiome in Allergies and Asthma: A Questionnaire-Based Study in Saudi Arabia

Purpose

Allergies and asthma are two noncommunicable illnesses of increasing public health concern in Saudi Arabia. Nevertheless, little is known about knowledge of the microbiome and its relationship to asthma and allergy risks among healthcare professionals, such as pediatricians and family medicine practitioners, who are often involved in the care of patients suffering from these illnesses. Therefore, this study aimed to examine knowledge about microbiome science in these healthcare workers in the eastern region of the kingdom, where allergies and asthma are highly prevalent.

Patients and Methods

The study survey consisted of 37 online questions in three topical domains, including microbiome science, dysbiosis, and probiotics, and was distributed to 203 participants in various demographic groups.

Results

The survey analysis revealed that the mean knowledge score was 67.6%. The component scores were highest for the microbiome (75.6%) and lowest for dysbiosis (52.6%). Only 17.7% of the healthcare workers were prescribing probiotic food or drinks for most of their patients with allergies and/or asthma; and 37.8% of the healthcare workers were unaware of the reasons for prescribing pro-/prebiotics. Regression analysis revealed that older age (>45 years old), probiotic prescription experience, and positive beliefs about the importance of nutritional advice were independent predictors of higher microbiome knowledge.

Conclusion

The analysis not only revealed existing gaps in microbiome knowledge among the participants, including those related to the role of the microbiome in allergy and asthma development but also identified predictors of higher microbiome knowledge. These observations provide an impetus for the rational design of continuing medical education curriculum and training to update healthcare professionals with emerging clinical application of microbiome knowledge for the management of microbiome-related illnesses.

Evaluating the knowledge on microbiome and dysbiosis in allergic diseases among medical sciences students in Saudi Arabia

BACKGROUND

Microbiome science deals with the development of diseases that are derived from the interaction between the host immune system and microbes. Microbiome disturbance or dysbiosis has been increasingly recognized as an important contributor to the pathogenesis of allergic diseases. Thus, this field is pivotal in the management of allergic disorders. Despite the increasing prevalence of allergic disorders in Saudi Arabia, medical students lack knowledge of microbiome science. Therefore, this study aimed to assess the level of knowledge of medical sciences students on the human microbiome, dysbiosis, and management of the impaired microbiome with a focus on allergic diseases and asthma.

METHODS

An online survey was designed, validated, and distributed to 100 final-year students and interns majoring in clinical nutrition, public health, and clinical laboratory sciences at a single university in Saudi Arabia. The study period was from November 2020 to January 2021.

RESULTS

The overall knowledge of the human microbiome was adequate among the participants, but their understanding of dysbiosis and management of the impaired microbiome was low to moderate. Knowledge of dysbiosis management was significantly higher in students majoring in clinical nutrition than in those majoring in public health and clinical laboratory sciences.

CONCLUSIONS

Collectively, this study provides the first evidence that knowledge of specific domains of microbiome science among a cohort of medical sciences students in Saudi Arabia is insufficient. Large-scale studies are warranted to confirm these observations at a national level, and specific curriculum modifications are necessary to improve the knowledge of future healthcare professionals about clinical applications of microbiome science.

Vitamin D and Microbiota: Is There a Link with Allergies?

There is increasing recognition of the importance of both the microbiome and vitamin D in states of health and disease. Microbiome studies have already demonstrated unique microbial patterns in systemic autoimmune diseases such as inflammatory bowel disease, rheumatoid arthritis, and systemic lupus erythematosus. Dysbiosis also seems to be associated with allergies, in particular asthma, atopic dermatitis, and food allergy. Even though the effect of vitamin D supplementation on these pathologies is still unknown, vitamin D deficiency deeply influences the microbiome by altering the microbiome composition and the integrity of the gut epithelial barrier. It also influences the immune system mainly through the vitamin D receptor (VDR). In this review, we summarize the influence of the microbiome and vitamin D on the immune system with a particular focus on allergic diseases and we discuss the necessity of further studies on the use of probiotics and of a correct intake of vitamin D.

The Role of Bacterial and Fungal Human Respiratory Microbiota in COVID-19 Patients

Recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), has led to a worldwide pandemic with millions of infected patients. Alteration in humans' microbiota was also reported in COVID-19 patients. The alteration in human microbiota may contribute to bacterial or viral infections and affect the immune system. Moreover, human's microbiota can be altered due to SARS-CoV-2 infection, and these microbiota changes can indicate the progression of COVID-19. While current studies focus on the gut microbiota, it seems necessary to pay attention to the lung microbiota in COVID-19. This study is aimed at reviewing respiratory microbiota dysbiosis among COVID-19 patients to encourage further studies on the field for assessment of SARS-CoV-2 and respiratory microbiota interaction.