Coronavirus diseases 2019(COVID 19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARA COV 2).

1. CORONA
VIRUS
DISEASE 2019
BY : Dr Muskan Agarwal

2. INTRODUCTION
• Coronavirus disease
2019 (COVID-19) is an infectious
disease caused by severe acute
respiratory syndrome coronavirus
2 (SARS-CoV-2)
• The disease was first identified in
December 2019 in Wuhan, the
capital of China.
• First isolated from three people
with pneumonia connected to
the cluster of acute respiratory
illness cases in Wuhan.

3. STRUCTURE OF CORONA
VIRUS
• Spherical or pleomorphic
enveloped particles
containing single-stranded
(positive-sense) RNA
associated with a
nucleoprotein within a
capsid comprised of matrix
protein. The envelope
bears club-shaped
glycoprotein projections.
• This gives it crown like
appearance hence named
corona (in latin)

4. ORIGIN OF VIRUS
• SARS-CoV-2 is closely related to
the original SARS-CoV.
• It is thought to have
a zoonotic origin. Genetic analysis
has revealed that the coronavirus
genetically clusters with the
genus Betacoronavirus, in
subgenus Sarbecovirus (lineage B)
together with two bat-derived
strains.
• It is 96% identical at the
whole genome level to other bat
coronavirus samples (BatCov
RaTG13).

5. TRANSMISSION
• The virus is
primarily spread between
people during close
contact(close contact being
within 1 to 2 metres (3 to
6 feet) often via small
droplets produced by
coughing,[b] sneezing, or
talking. •People may also
become infected by
touching a
contaminated surface
and then touching
their face

6. • The droplets usually fall to
the ground or onto
surfaces rather
than remaining in the
air over long distances.
• The droplets can land in
the mouths or noses of
people who are nearby or
possibly be inhaled into
the lungs.[

7. • Some medical
procedures such as
intubation
and cardiopulmonary
resuscitation (CPR) may
cause respiratory
secretions to be
aerosolised and thus
result in airborne
spread

8. • It is most contagious during the first three days after the onset
of symptoms, although spread may be possible before
symptoms appear and in later stages of the disease.
•The virus survives for hours
to days on
surfaces. Specifically, the
virus was found to be
detectable for up to three
days on plastic
(polypropylene) and 304
stainless steel, for one day on
cardboard, and for up to four
hours on copper.This,
however, varies based on the
humidity and temperature.

9. • Pets and other animals have
tested positive for COVID-
19.There is no evidence animals
can pass the virus on to
humans, though British
authorities advise washing
one's hands after contact with
animals, like after contact with
other potentially contaminated
surfaces.

10. PATHOPHYSIOLOGY
LUNGS
• The lungs -most affected
,because the virus accesses
host cells via the
enzyme angiotensin-
converting enzyme 2( most
abundant in type II alveolar
cells of the lungs)
• The virus uses a special
surface glycoprotein called a
"spike" (peplomer) to connect
to ACE2 and enter the host
cell.

11. GASTROINTESTINAL ORGANS
• The virus also affects
gastrointestinal organs as ACE2 is
abundantly expressed in
the glandular cellsof gastric, duodenal
and rectal epithelium[84] as well
as endothelial cells and enterocytes of
the small intestine
BRAIN
• ACE2 is present in the brain, and there
is growing evidence of neurological
manifestations in people with
COVID-19. It is not certain if the virus
can directly infect the brain by
crossing the barriers that separate the
circulation of the brain and the
general circulation.

12. HEART
• The virus can cause acute
myocardial injury and chronic
damage to the cardiovascular
system.
• ACE2 receptors are highly
expressed in the heart and are
involved in heart function.A
high incidence
of thrombosis (31%)
and venous
thromboembolism (25%) have
been found in ICU patients
with COVID-19 infections and
may be related to poor
prognosis.

13. KIDNEY
• Another common cause of
death is complications related
to the kidneys[93]—SARS-CoV-2
directly infects kidney cells, as
confirmed in post-mortem
studies. Acute kidney injury is a
common complication and
cause of death Especially in
people with pre-existing chronic
conditions such as hypertension
and diabetes which specifically
cause nephropathy in the long
run.

14. SIGNS AND SYMPTOMS
• Common symptoms –
• fever(88%)
• cough(68%)
• fatigue
• shortness of breath
• loss of smell.

15. • Emergency symptoms include difficulty
breathing, persistent chest pain, confusion,
difficulty waking, and bluish skin.
• Further development of the disease can lead to
potentially fatal complications
including pneumonia, acute respiratory distress
syndrome, sepsis, septic shock, and kidney
failure.
• Some of those infected may be asymptomatic,
with no clinical symptoms but test results that
confirm infection

16. INCUBATION PERIOD
• The time from exposure to onset of
symptoms is typically around five days but
may range from two to fourteen days

17. IMMUNOPATHOLOGY
• Although SARS-COV-2 has a tropism for ACE2-expressing
epithelial cells of the respiratory tract, patients with severe
COVID-19 have symptoms of systemic hyper inflammation.
• Clinical laboratory findings of elevated IL-2, IL-7, IL-
6, granulocyte-macrophage colony-stimulating factor (GM-
CSF), interferon-γ inducible protein 10 (IP-10), monocyte
chemoattractant protein 1 (MCP-1), macrophage
inflammatory protein 1-α (MIP-1α), and tumour necrosis
factor-α (TNF-α) indicative of cytokine release
syndrome (CRS) suggest an underlying immunopathology.
• people with COVID-19 and acute respiratory distress
syndrome (ARDS) have classical serum biomarkers of CRS,
including elevated C-reactive protein (CRP), lactate
dehydrogenase (LDH), D-dimer, and ferritin

18. DIAGNOSIS
• COVID-19 can be provisionally diagnosed on
the basis of symptoms and signs then
confirmed using reverse transcription
polymerase chain reaction (rRT-PCR) testing of
infected secretions or CT imaging of the chest.

19. • Viral testing
• The standard test for current infection with
SARS-CoV-2 uses RNA testing of respiratory
secretions collected using a nasopharyngeal
swab. This test uses real-time rRT-PCR which
detects presence of viral RNA fragments.

20. • A number of laboratories and companies are
developing serological tests, which
detect antibodies produced by the body in
response to infection
Imaging
• A CT scan of the chest of a person with COVID-19.
It shows light patches in the lungs.
• Characteristic imaging features on
chest radiographs and computed
tomography (CT) of people who are symptomatic
include asymmetric peripheral ground-glass
opacities without pleural effusions.