Coronavirus

Coronaviruses (CoV) are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV).
A novel coronavirus (nCoV) is a new strain that has not been previously identified in humans.
The virus is named after its shape which takes the form of a crown with protrusions around it and hence is known as coronavirus.

Structure of SARS COV-2:

Like other coronaviruses, SARS-CoV-2 virus particles are spherical and have mushroom-shaped proteins called spikes protruding from their surface, giving the particles a crown-like appearance.
The spike binds and fuses to human cells, allowing the virus to gain entry.
Like SARS coronavirus, the spike protein of the SARS-CoV-2 that causes Coronavirus Disease 19 (COVID-19) binds to the cellular receptor called angiotensin-converting enzyme 2 (ACE2), which serves as the entry point into human cells.
But unlike in the case of SARS, the spike protein of the novel coronavirus binds to the cell receptor with much higher affinity — 10- to 20-fold higher.

How does it spread?

Coronaviruses are zoonotic, meaning they are transmitted between animals and people.
Detailed investigations found that SARS-CoV was transmitted from civet cats to humans and MERS-CoV from dromedary camels to humans.
The COVID-19 virus spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes

Common signs of infection include respiratory symptoms, fever, cough, shortness of breath and breathing difficulties.
In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome, kidney failure and even death.

Standard recommendations to prevent infection spread include regular hand washing, covering mouth and nose when coughing and sneezing, thoroughly cooking meat and eggs.
Avoid close contact with anyone showing symptoms of respiratory illness such as coughing and sneezing.

SARS (Severe Acute Respiratory Syndrome) coronavirus (SARS-CoV) – virus identified in 2003.
SARS-CoV is thought to be an animal virus from an as-yet-uncertain animal reservoir, perhaps bats, that spread to other animals (civet cats) and first infected humans in the Guangdong province of southern China in 2002.
Transmission of SARS-CoV is primarily from person to person.
Symptoms are influenza-like and include fever, malaise, myalgia, headache, diarrhoea, and shivering (rigors).
No vaccines or Prophylaxis (prevention of disease) treatment available.
WHO estimates that the case fatality ratio of SARS ranges from 0% to 50% depending on the age group affected, with an overall estimate of case fatality of 14% to 15%.

Middle East respiratory syndrome (MERS) is a viral respiratory disease caused by a novel coronavirus (Middle East respiratory syndrome coronavirus, or MERS‐CoV) that was first identified in Saudi Arabia in 2012.
Typical MERS symptoms include fever, cough and shortness of breath. Pneumonia is common, but not always present.
Approximately 35% of reported patients with MERS-CoV infection have died.
MERS-CoV is a zoonotic virus, which means it is a virus that is transmitted between animals and people.
Studies have shown that humans are infected through direct or indirect contact with infected dromedary camels.
No vaccine or specific treatment is currently available, however several MERS-CoV specific vaccines and treatments are in development.

Why in the news?

The number of people infected with SARS COV-2 pandemic is increasing day by day all over the world.

What is a Pandemic?

A pandemic is defined as an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people.
COVID-19 is the first pandemic caused by a coronavirus.

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