INTRODUCTION TO
CORONAVIRUS DISEASES
Submitted BY : RUCHIRA BALVIR
SESSION : 2019 – 2020
B.SC IN NUTRITION & DIETETICS

WHAT IS CORONA VIRUS ?
 A coronavirus is a kind of common virus that causes an infection in your
nose, sinuses, or upper throat. Most coronaviruses aren't dangerous.
 Coronaviruses are a type of virus. There are many different kinds, and
some cause disease. A newly identified coronavirus, SARS-CoV-2, has
caused a worldwide pandemic of respiratory illness, called COVID-19.
 Most people infected with the COVID-19 virus will experience mild to
moderate respiratory illness and recover without requiring special
treatment. Older people, and those with underlying medical problems like
cardiovascular disease, diabetes, chronic respiratory disease, and cancer
are more likely to develop serious illness.
 The COVID-19 virus spreads primarily through droplets of saliva or
discharge from the nose when an infected person coughs or sneezes, so
it’s important that you also practice respiratory etiquette (for example, by
coughing into a flexed elbow).

WHAT YOU NEED TO KNOWCOVID-19

WHERE DID THE COVID-19 COME FROM ?
 Experts say SARS-CoV-2 originated in bats.That’s also how the coronaviruses behind
Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome
(SARS) got started.
 The virus that was first first detected in wuhan ,china, in late 2019 and has set
off a global pandemic.SARS-CoV-2 made the jump to humans at one of Wuhan’s
open-air “wet markets.”They’re where customers buy fresh meat and fish, including
animals that are killed on the spot.
 Some wet markets sell wild or banned species like cobras, wild boars, and raccoon dogs.
Crowded conditions can let viruses from different animals swap genes. Sometimes the
virus changes so much it can start to infect and spread among people.
 As SARS-CoV-2 spread both inside and outside China, it infected people who
have had no direct contact with animals. That meant the virus is transmitted
from one human to another. It’s now spreading in the U.S. and around the
globe, meaning that people are unwittingly catching and passing on the
coronavirus. This growing worldwide transmission is what is now a pandemic.
.

CORONA VIRUS EVOLUTION
Scientists first identified a human coronavirus in 1965. It
caused a common cold. Later that decade, researchers
found a group of similar human and animal viruses and
named them after their crown-like appearance.
Seven coronaviruses can infect humans.The one that
causes SARS emerged in southern China in 2002 and
quickly spread to 28 other countries. More than 8,000
people were infected by July 2003, and 774 died.A small
outbreak in 2004 involved only four more cases.This
coronavirus causes fever, headache, and respiratory
problems such as cough and shortness of breath.
MERS started in SaudiArabia in 2012.Almost all of the
nearly 2,500 cases have been in people who live in or
travel to the Middle East.This coronavirus is less
contagious than its SARS cousin but more deadly, killing
858 people. It has the same respiratory symptoms but can
also cause kidney failure.

HUMAN COVID-19 DISCOVERIES
 IN 1965,Researchers at the Common Cold Research Unit in Wiltshire, UK, report
cultivating a virus, B814, from a boy with a cold. They describe the pathogen as
“virtually unrelated to any other known virus of the human respiratory tract.
 IN 1966, Dorothy Hamre and John Procknow of the University of Chicago describe a
virus, which they dub 229E, isolated from a medical student with a cold. It is
distinct from other known respiratory viruses.
 IN 1967, Scientists at the National Institute of Allergy and Infectious Diseases
report using the same methods used to culture B814 to grow another new human
virus with a similar morphology. They name the virus OC43.
 IN1968, Eight researchers, including the discoverers of B814, 229E, and OC43 and
June Almeida, who first imaged coronaviruses, write to Nature to propose that
these and several other recently isolated human viruses belong to a new category,
coronaviruses. These viruses, they say, have a “characteristic ‘fringe’ of
projections 200 Å long, which are rounded or petal shaped . . . recalling the solar
corona . . .” (Samples of B814 and the unnamed other viruses are no longer
available for study, but Jeffrey Kahn of UT Southwestern Medical Center suggests
they may have been the same cold-causing coronaviruses that were characterized
and named in the mid-2000s.)

 IN 2003,An international group of researchers reports that the
outbreak of severe acute respiratory syndrome (SARS), which began in
late 2002 in southern China, is caused by a newly emerged human
coronavirus.
 IN 2004,Researchers at Erasmus Medical Center in the Netherlands
report isolating a coronavirus, later named NL63, from a child with
pneumonia.
 IN 2005, A group of researchers based at the University of Hong Kong
discovers another coronavirus, HKU1, in samples from two patients
with pneumonia.
 IN 2012, Researchers at Erasmus Medical Center and their colleagues
identify a new coronavirus, later named MERS-CoV, that was isolated
from a man in Saudi Arabia with pneumonia and Kidney Failure.
 IN 2020,A team of researchers in China identify the cause of a disease
outbreak in Wuhan as a novel coronavirus, now known as SARS-CoV-2.

COROVA VIRUS
BELONGS TO :
REALM : ROBOVIRIA
PHYLUM : INCERTAE SEDI
ORDER : NID0VIRALES
FAMILY : CORONAVIRIDAE
SUB- FAMILY
:ORTHOCORONAVIRIDAE

STRUCTURE OF
CORONAVIRUS
SARS –COV-2 PATICLES ARE SPHERICAL AND
HAS PROTEINS CALLED SPIKES .
THESE ARE ENVELOPED VIRION ,POSITIVE
SENSE,SINGLE STRANDARD ,LARGEST RNA
VIRUS ,80-160 NANOMETERS IN DIAMETER
,GENOME RANGES FROM 26-36 KBS .
STRUCTURAL PROTEIN
S {SPIKE}
N {NEUCLEOCASPID}
E {ENVELOPE }
M {MEMBRANE }
HE {HEMAGLUTINESTERASE}

 S Proteins together with HE protein assist in viral entry to
the human cell .
 S protein attaches to the receptor protein ACE2 .
 CROWN – Like appearance .
 RIBONUCLEOPROTEIN
 N protein forms a complex with RNA assist in viral
assembly .
 E proteins form the viral envelope .
 E1 is a matrix glycoprotein –transmembrane protein .
 E2 peplogenic –fusion .
 M proteins form the viral envelope.
 HE Hemaglutin is a peplomer with a role in
hemaglutinatination .

TRANSMISSION ROUTES
Droplet and Airborne routes create most
debate.
Continuum of droplet and airborne routes an
important concept
Particles of a variety of sizes are expelled from
the human airway during coughing ,sneezing
,talking and medical procedures
Dreoplet spread refers to large droplets (>5 -
10um )that fall within 1 metre
Probability of transmission followed by invasive
infection : many factors
Host susceptibility
Presence of host receptors
Receptivity of host receptors
Incoculum
Virulence
viability

CURRENT SCENARIO :
Globally, as of 3:40pm CEST,
9 October 2020, there have
been 36,996,501 confirmed
cases of COVID-19,
including 1,069,476 deaths,
reported to WHO
Confirmed cases :36 996 501
Confirmed deaths :1 069 476
Countries, areas or
territories with cases235

SIGNS & SYMPTOMS OF COVID -19 :

DIAGNOSIS :
 TRAVEL HISTORY to endemic countries like ( china ,iran
&Italy )
 CBC (Leukopenia ,seen in 30 % to 45 % of patients ,&
lymphocytopenia ,seen in 85 % of the patients )
 CHEST X-RAY (CHEPEAR & EASIER WITH 60 % SENSITIVITY )
 PCR (30 % - 70 % sensitivity )
 Chest CT SCAN (95 % sensitivity ,low specificity )
 IgM /IgG COMBO TEST for covid -19

TREATMENT
 MILD CASES : Supportive treatments ( Antihistamine & Analgesics )
 MODERATE CASES
 Oseltamivir ( 150 mg BID for 5 days )
 Hydroxychloroquine ,chloroquine (500 mg BID for 14 days ) or Ribavirin ( for 5
days )
 SEVERE CASES :
 Oseltamivir (150 mg BID for 5 days )
 Kaletra (Lopinavir/ritonavir ) ( for 5 days )
 Hydroxychloroquine ,chloroquine ( 500 mg BID for 14 days ) or Ribavirin (for 5
days )
 CRITICAL CASES
Oseltamivir (150 mg BID for 5 days )
 Kaletra /ribavirin ( for 5 days )
 Hydroxychloroquine or Chloroquine ( for 14 days )

PREVENTION :

THANK YOU