New Corona Virus: COVID-19

About Corona

Animal coronaviruses were first described in 1930. The first report of human coronavirus was in 1965 by David Arthur John Tyrrell and his team. (1) He isolated a virus from the nasal washings of a male child. The child had typical symptoms of a common cold. Common colds account for a third of all acute respiratory infection in the Western World. The virus was termed B814 after the number of the nasal washing. Due to the characteristic morphology of these agents, Tyrrell proposed the term “Coronavirus” in 1968 which was broadly accepted. Tyrrell (1925–2005) was a British virologist and the final director of the Medical Research Council's Common Cold Unit.

Virus classification

Coronaviruses are pathogenic for animals and humans. The coronaviruses typically cause respiratory symptoms mainly of the upper respiratory tract, in some cases also of the lower respiratory tract. The family Coronaviridae comprises 4 genera of which alpha coronavirus and beta coronavirus are pathogenic for humans and animals. Gamma coronavirus and delta coronavirus are specific for animals. Among the seven corona strains circulating in the human population are three strains that are potentially severe:

1. Middle East respiratory syndrome-related coronavirus (MERS-CoV), known as novel coronavirus 2012 and HCoV-EMC: 2 main outbreaks, 2012 and 2015

2. Severe acute respiratory syndrome coronavirus (SARS-CoV): Outbreak 2003

and since December 2019:

3. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), known as newCOVID-19 or novel coronavirus 2019. On February 11th 2020 the WHO definitively named the new coronavirus 2019 SARS-Cov-2 and the disease caused by this virus was named ‘Coronavirus Disease 2019’ (COVID-19).

In 2017 the impact of co-infection of influenza A virus on the severity of Middle East Respiratory Syndrome Coronavirus was reported. (2) Currently SARS-CoV-2 is co-circulating with Influenza A(H1N1). Bothe viruses provoke similar symptoms. On this ground every suspected patient should be tested for both viruses. A flu vaccine does exist.

Virus Biology

Coronaviruses are enveloped single stranded (ss) RNA Virus, 80 to 120 nm in size. The genome comprises about 31,000 nucleotides. Coronaviruses encode three conserved membrane-associated proteins that are incorporated in virions: spike (S), envelope (E), membrane (M), and nucleoprotein (N). These four proteins occur in the order S–E–M–N in every known coronavirus lineage. (3) The other 10 proteins are non-structural proteins.

COVID-19: Symptoms

COVID-19 typically causes flu-like symptoms as fever, cough, sore throat and fatigue, shortness of breath. COVID-19 may present with mild, moderate, or severe illness; the latter includes severe pneumonia, ARDS (Acute Respiratory Distress Syndrome), sepsis and septic shock: