Coronavirus

Background

• Coronaviruses are enveloped, positive-stranded RNA viruses that were first discovered in the 1960s and named after the crown-like spikes on their surface seen on electron microscopy.
• They have a nucleocapsid around them and are the largest RNA virus.
• Four main subtypes of Coronavirus: alpha, beta, gamma, delta.
• Coronavirus is very common and most people will get infected atleast once in their lifetime, esp children but route of infection is controversial. Most common time of infection is fall or winter.
• The cause of Coronavirus is hard to assess since it cannot be grown in laboratories, the way Rhinovirus can be grown (another common cold virus).
• Commonly cause up to one-third of upper respiratory tract infections in adults and children.
  • Also thought to cause diarrhea in infants, children, and farm animals.
• MERS-CoV and SARS-CoV types of Coronavirus cause the most severe infections.
  • SARS began in 2002 in Asia.

Method of Replication

• Coronavirus enters the cell cytoplasm and viral particle is uncoated causing RNA genome to deposit into cytoplasm.
• RNA viral genome is transcribed into new RNA copies via replicase protein.

Clinical Features

• Coronavirus usually presents like the common cold with an upper respiratory tract infection: runny nose, cough, fever, sore throat.
• Pulmonary - coughing, dyspnea/wheezing, respiratory failure (seen in elderly/immunocompromised), pneumonia, secondary bacterial pneumonia.
• GI - vomiting, diarrhea, Necrotizing enterocolitis (in neonates)
• HEENT - otalgia, coryza, rhinorrhea, sneezing

Differential Diagnosis

• Rhinovirus: most common cold virus. Causes around 40% colds.
  • as opposed to Coronavirus, this causes cold in other seasons besides winter.
• respiratory syncytial virus (RSV)
• influenza
• parainfluenza

Evaluation

• Generally no evaluation indicated
• If needed, nasal swabs can be sent for PCR and immunofluorescent antigen assay

Prevention

• No vaccines have been made thus far to prevent Coronavirus.
• Measures to reduce risk of transmission: fully wash hands, do not touch face without washing hands, avoid close contact with sick contacts.

Management

• Supportive care
• There is no specific treatment for Coronavirus, since most infections spontaneously resolve.
• Pain and fever medications can be taken (do not give aspirin to kids).

External Links

http://www.cdc.gov/coronavirus/about/ https://en.wikipedia.org/wiki/Coronavirus