The Importance of Glycans of Viral and Host Proteins in Enveloped Virus Infection.

Animal viruses are parasites of animal cells that have characteristics such as heredity and replication. Viruses can be divided into non-enveloped and enveloped viruses if a lipid bilayer membrane surrounds them or not. All the membrane proteins of enveloped viruses that function in attachment to target cells or membrane fusion are modified by glycosylation. Glycosylation is one of the most common post-translational modifications of proteins and plays an important role in many biological behaviors, such as protein folding and stabilization, virus attachment to target cell receptors and inhibition of antibody neutralization. Glycans of the host receptors can also regulate the attachment of the viruses and then influence the virus entry. With the development of glycosylation research technology, the research and development of novel virus vaccines and antiviral drugs based on glycan have received increasing attention. Here, we review the effects of host glycans and viral proteins on biological behaviors of viruses, and the opportunities for prevention and treatment of viral infectious diseases.

Transmission routes of 2019-nCoV and controls in dental practise

A novel beta-coronavirus (2019, nCoV) caused severe and even fatal pneumonia explored in a seafood market of Wuhan city, Hubei province China, and rapidly spread to other province China and other countries. The 2019-nCoV was different Iron SARS-CoV, but shared the same host receptor the human angiotensin-converting enzymes 2 (ACE2). The natural last of 2019-nCOv may be the bat Rhinolophus affinis as 2019-nCoV stoned 96.2% of whole-genome identity to BatCoV RagTG13. The person to person-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze. droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes, 2019-nCoV can also be transmitted through the Saliva, and the fecal-oral routes may also be a potential person-to-person transmission route The participants in dental practice expose to tremendous risk of 2019-nCov infection due to the face-to-face communication and the exposure to saliva, blood, and Other body fluids, and the handling of sharp instrument. Dental professional play great roles in preventing the transmission of 2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.

The microbial coinfection in COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel ß-coronavirus, is the main pathogenic agent of the rapidly spreading pneumonia called coronavirus disease 2019 (COVID-19). SARS-CoV-2 infects much more people, especially the elder population, around the world than other coronavirus, such as SARS-CoV and MERS-CoV, which is challenging current global public health system. Beyond the pathogenesis of SARS-CoV-2, microbial coinfection plays an important role in the occurrence and development of SARS-CoV-2 infection by raising the difficulties of diagnosis, treatment, prognosis of COVID-19, and even increasing the disease symptom and mortality. We summarize the coinfection of virus, bacteria and fungi with SARS-CoV-2, their effects on COVID-19, the reasons of coinfection, and the diagnosis to emphasize the importance of microbial coinfection in COVID-19. KEY POINTS: • Microbial coinfection is a nonnegligible factor in COVID-19. • Microbial coinfection exacerbates the processes of the occurrence, development and prognosis of COVID-19, and the difficulties of clinical diagnosis and treatment. • Different virus, bacteria, and fungi contributed to the coinfection with SARS-CoV-2.

Saliva is a non-negligible factor in the spread of COVID-19.

SARS-CoV-2, a novel emerging coronavirus, has caused severe disease (COVID-19), and rapidly spread worldwide since the beginning of 2020. SARS-CoV-2 mainly spreads by coughing, sneezing, droplet inhalation, and contact. SARS-CoV-2 has been detected in saliva samples, making saliva a potential transmission route for COVID-19. The participants in dental practice confront a particular risk of SARS-CoV-2 infection due to close contact with the patients and potential exposure to saliva-contaminated droplets and aerosols generated during dental procedures. In addition, saliva-contaminated surfaces could lead to potential cross-infection. Hence, the control of saliva-related transmission in the dental clinic is critical, particularly in the epidemic period of COVID-19. Based on our experience of the COVID-19 epidemic, some protective measures that can help reduce the risk of saliva-related transmission are suggested, in order to avoid the potential spread of SARS-CoV-2 among patients, visitors, and dental practitioners.

Transmission routes of 2019-nCoV and controls in dental practice.

A novel ß-coronavirus (2019-nCoV) caused severe and even fetal pneumonia explored in a seafood market of Wuhan city, Hubei province, China, and rapidly spread to other provinces of China and other countries. The 2019-nCoV was different from SARS-CoV, but shared the same host receptor the human angiotensin-converting enzyme 2 (ACE2). The natural host of 2019-nCoV may be the bat Rhinolophus affinis as 2019-nCoV showed 96.2% of whole-genome identity to BatCoV RaTG13. The person-to-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze, droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes. 2019-nCoV can also be transmitted through the saliva, and the fetal-oral routes may also be a potential person-to-person transmission route. The participants in dental practice expose to tremendous risk of 2019-nCoV infection due to the face-to-face communication and the exposure to saliva, blood, and other body fluids, and the handling of sharp instruments. Dental professionals play great roles in preventing the transmission of 2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.