No abstract

The pandemic coronavirus disease 2019 (COVID‐19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2), has affected millions of people worldwide. To date, there are no proven effective therapies for this virus. Efforts made to develop antiviral strategies for the treatment of COVID‐19 are underway. Respiratory viral infections, such as influenza, predispose patients to co‐infections and these lead to increased disease severity and mortality. Numerous types of antibiotics such as azithromycin have been employed for the prevention and treatment of bacterial co‐infection and secondary bacterial infections in patients with a viral respiratory infection (e.g., SARS‐CoV‐2). Although antibiotics do not directly affect SARS‐CoV‐2, viral respiratory infections often result in bacterial pneumonia. It is possible that some patients die from bacterial co‐infection rather than virus itself. To date, a considerable number of bacterial strains have been resistant to various antibiotics such as azithromycin, and the overuse could render those or other antibiotics even less effective. Therefore, bacterial co‐infection and secondary bacterial infection are considered critical risk factors for the severity and mortality rates of COVID‐19. Also, the antibiotic‐resistant as a result of overusing must be considered. In this review, we will summarize the bacterial co‐infection and secondary bacterial infection in some featured respiratory viral infections, especially COVID‐19.

No abstract

Highlights The pandemic of COVID-19 has imposed significant public health problems globally. MiRNAs play a significant role in the control of various cellular processes against viral infections. The pattern of expression of miRNA may be involved in the severity of COVID-19. Host miRNAs may have both functions, antiviral, or promote infection. MiRNAs can act as a means of preventing, diagnosing and curing viral infections.

Biofilms are microbial communities established in the self‐produced extracellular substances that include up to 80% of associated microbial infections. During biofilm formation, bacterial cells shift from the planktonic forms to aggregated forms surrounded by an extracellular polymeric substance. The bacterial biofilm shows resistance against immune reactions as well as antibiotics and is potentially able to cause disorders by both device‐related and nondevice‐related infections. The nondevice‐related bacterial biofilm infections include dental plaque, urinary tract infections, cystic fibrosis, otitis media, infective endocarditis, tonsillitis, periodontitis, necrotizing fasciitis, osteomyelitis, infectious kidney stones, and chronic inflammatory diseases. In this review, we will summarize and examine the literature about bacterial biofilm infections unrelated to indwelling devices.

COVID-19 is an acute respiratory infection accompanied by pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has affected millions of people globally. To date, there are no highly efficient therapies for this infection. Probiotic bacteria can interact with the gut microbiome to strengthen the immune system, enhance immune responses, and induce appropriate immune signaling pathways. Several probiotics have been confirmed to reduce the duration of bacterial or viral infections. Immune fitness may be one of the approaches by which protection against viral infections can be reinforced. In general, prevention is more efficient than therapy in fighting viral infections. Thus, probiotics have emerged as suitable candidates for controlling these infections. During the COVID-19 pandemic, any approach with the capacity to induce mucosal and systemic reactions could potentially be useful. Here, we summarize findings regarding the effectiveness of various probiotics for preventing virus-induced respiratory infectious diseases, especially those that could be employed for COVID-19 patients. However, the benefits of probiotics are strain-specific, and it is necessary to identify the bacterial strains that are scientifically established to be beneficial.

Highlights Currently, no proven effective therapies or preventive vaccines for SARAS-CoV-2 exist. Effective vaccines against COVID-19 are urgently required to overcome the SARAS-CoV-2. Several approaches are underway for vaccines developed against SARS-CoV-2. Some clinical trials are launched in several countries.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), has been the world’s driving fatal bacterial contagious disease globally. It continues a public health emergency, and around one-third of the global community has been affected by latent TB infection (LTBI). This is mostly due to the difficulty in diagnosing and treating patients with TB and LTBI. Exosomes are nanovesicles (40–100 nm) released from different cell types, containing proteins, lipids, mRNA, and miRNA, and they allow the transfer of one’s cargo to other cells. The functional and diagnostic potential of exosomal miRNAs has been demonstrated in bacterial infections, including TB. Besides, it has been recognized that cells infected by intracellular pathogens such as Mtb can be secreting an exosome, which is implicated in the infection’s fate. Exosomes, therefore, open a unique viewpoint on the investigative process of TB pathogenicity. This study explores the possible function of exosomal miRNAs as a diagnostic biomarker. Moreover, we include the latest data on the pathogenic and therapeutic role of exosomal miRNAs in TB.