1) Coronaviruses were first identified in 1965 and can infect birds and mammals. They derive their name from crown-like spikes on their surface. 2) A new coronavirus emerged from Wuhan, China called 2019-nCoV which has spread rapidly worldwide, killing many people. It causes respiratory illness and pneumonia. 3) Coronaviruses can be transmitted between humans in rare cases, as with 2019-nCoV, in a process called zoonosis. More research is needed to treat and prevent infection from these viruses.

1. CORONAVIRUSES(CoVs)- A GLOBAL EMERGENCY
Bilal Ahmad Mir
Research Scholar
Department Of Zoology
Maulana Azad National University
Hyderabad
sagar.bilal19@gmail.com
Coronaviruses (CoVs) were identified in 1965 to infect birds and mammals. They were so
named because of the spike proteins emanated from these viruses which gave them a
crownlike appearence. Coronaviruses are known to be 20 nm long and are recognised by club
shaped surface projections and resemble like solar coronas. These viruses are characterized
by their ability to Cause the common cold especially in older childrens and adults. They
represent order Nidovirals, faimly Coronaviridae, subfaimly Coronavirinae. they are
relatively large (120-150 nm), composed of +ive strand RNA varying in length from 26 to 32
kilobases (kb) (largest genome for RNA viuses) within the helical nucleocapside, surrounded
by the envelope. The envelope proteins are coded by The CoV E protein that has recently
been found to contain a binding motif known as the postsynaptic density protein 95 (PSD95).
This domain is a protein-protein interaction module that can bind to the target proteins such
as the cellular adapter proteins involved in host-cell processes important for viral infection.
Corona viruses have been classified into three main categories based on the antigenic criteria;
α-CoVs, β-CoVs, and μCoVs. Large peplomers (spikes) come out of the envelope in order to
help bind and enter the virus in the host cell. The protruding peplomers extend from the oval
to spherical virion to give the illusion of a halo, or corona, around the virus. The peplomer
protein mediates viral attachment and fusion to the host cell membrane.
A new type of corona virus has emerged from the city of Wuhan in china named as 2019
Novel Coronavirus (2019-nCoV). Within weeks, it has spread to the several countries and has
killed many people. As an RNA virus, 2019-nCoV still has the inherent feature of a high
mutation rate. This aspect provides the possibility for this newly introduced zoonotic viral
pathogen to adapt to become more efficiently transmitted from person to person and possibly
become more virulent. Infection of this novel coronavirus causes respiratory illness among
humans. Patients with 2019-nCoV have reportedly had shortness of breath, fever, cough and
severe complications include pneumonia in both lungs.

2. Coronaviruses are a large group among bird and mammals but in rare cases like this one,
they are transmitted between humans- a process known as zoonosis but it is still unclear
whether this happens routinely. This new virus is the seventh known corona virus but is
considered not as deadly as SARS that killed 11%of people it infected. Though there are
several human CoV responsible for a mild respiratory disease, most notable are the highly
pathogenic human CoVs: SARS-CoV and MERS-CoV capable of causing a severe
respiratory disease
The initial outbreak of SARS originated in chaina in late 2002, and it spread rapidly to atleast
29 other countries by summer 2003. The outbreak resulted in 8098 persons with possible
SARS, including 744 deaths being reported by WHO. There were 373 possible SARS cases
in the united states; however, SARS-CoV identification has been confirmed only in 8 of
them. seven of the eight cases were likely due exposure to one of the other seven. The 2003
SARS epidemic demonstrated to the world the ease with which a virus can spread. SARS-
CoV virions use the angiotensin-converting enzyme 2 (ACE2) on the host cells as the virus
receptor. A receptor-binding domain of the peplomer is complementary to the ACE2 receptor
creating a binding interface.
The coronavirus that caused the outbreakof severe acute respiratory syndrome, or SARS.
(a) The virus is studded with spikes that in cross-section give it the appearance of acrown, hence the name
coronavirus.
(b) The human receptor for the SARS virus is angiotensin-converting enzyme 2 (ACE2).
The virus causes a lower respiratory tract disease which is febrile (100.4, 38oc). Sudden,
fatal illness is a characteristic of the disease in people who are otherwise healthy. Other signs
may include headache, pain with the flulike discomfort; and body aches. After a couple of
days, patients may develop a dry cough, and most will develop pneumonia. Approximately

3. 10-20 per cent has diarrhoea. If not detected early, even with supportive care, this illness can
be fatal. Rapid detection and prevention measures were pursued during and after the
outbreak. Diligent screening for signs of fever or respiratory disease at airports and the
initiation of SARS-CoV vaccine trails are two examples of protective measures.
Table: The clinical features of 2019-nCoV, in comparison with SARS-CoV and Middle East
respiratory syndrome (MERS)-CoV
Source: Wang et al; 2020
The researchers believe that the novel coronavirus (2019-nCoV) was orginated in the Wuhan
market by an unknown species. Identifying that animal could help control the current
outbreak. No known medicines are currently approved which can effectively treat infections
of Coronavirus in humans and no vaccines are currently licensed. It could be helpful to
prevent infection by blocking the receptor used by the virus to infect the cell. The high
mortality rates of novel coronavirus (2019-nCoV) and their effective transmission underline
the need for further research to highlight the specific structural requirements for its function

4. in the life cycle and mechanisms behind their pathogensis. This will help in the
production effective anticoronaviral agents.