corona slide

1. Coronavirus(covid-19)
The name "coronavirus" is derived from Latin corona meaning "crown" or
"wreath", itself a borrowing from Greek κορώνη korṓnē, "garland,
wreath".[The name was coined by June Almeida and David Tyrrell who first
observed and studied human coronaviruses.
Family: coronaviridae
Class: pisoniviricetes
Phylum: pisuviricota
Kingdom: orthornavirae
 Coronavirus disease 2019 (COVID-19) is defined as illness caused by a novel
coronavirus now called severe acute respiratory syndrome coronavirus 2 (SARS-
CoV-2; formerly called 2019-nCoV), which was first identified amid an outbreak of
respiratory illness cases in Wuhan City, Hubei Province, China. It was initially reported to
the WHO on December 31, 2019. On January 30, 2020, the WHO declared the COVID-19
outbreak a global health emergency. On March 11, 2020, the WHO declared COVID-19 a
global pandemic, its first such designation since declaring H1N1 influenza a pandemic
in 2009. That cause disease in mammals and birds like bats.

2. history
 in 1965 when Tyrrell and Bynoe1 found that they could passage a virus named
B814. It was found in human embryonic tracheal organ cultures obtained from the
respiratory tract of an adult with a common cold.
 In one study carried out in Canada in 2001,more than 500 patients presented with flu-like
symptoms. Until 2002corona virus was considered a relatively simple, nonfatal virus however,
an outbreak in2002–2003 in Guangdong province in China, which resulted in spread to many
other countries, including Thailand, Vietnam, Taiwan, Hong Kong Singapore
 Human coronaviruses, first discovered in the 1960s, are responsible for a substantial
proportion of upper respiratory tract infections in children.
I ndeed, another outbreak in Saudi Arabia in 2012 resulted in many deaths and spread
first to other countries in the Middle East and then worldwide,
 coronaviruses have since been identified, includin ”SARS-CoV” in 2003,” HCoV
NL63” in 2004,” HCoV HKU1” in 2005,” MERS-CoV” in 2012, and” SARS-CoV-2” in
2019.

3.  On 31 December 2019, health authorities in China reported to the World Health
Organization (WHO) a cluster of viral pneumonia cases of unknown cause in Wuhan,
Hubei and an investigation was launched in early January 2020.On 30 January, the
WHO declared the outbreak a Public Health Emergency of International Concern
(PHEIC)—7818 cases confirmed globally, affecting 19 countries in five WHO regions.
The earliest known person with symptoms was later discovered to have fallen ill on
1 December 2019, and that person did not have visible connections with the later wet
market cluster
 On 13 March 2020, an unverified report from the South China Morning Post suggested a
case traced back to 17 November 2019 (a 55-year-old from Hubei) may have been the first
person infected.
 he WHO recognized the spread of COVID-19 as a pandemic on 11 March
2020. Italy, Iran, South Korea, and Japan reported surging cases. The total numbers
outside China quickly passed China‘s.
 The first confirmed death was in Wuhan on 9 January 2020.The first death outside of
China occurred on 1 February in the Philippines,and the first death outside Asia was in
France on 14 February.
Epidemiology

4. Various corona viruses are
infected in human
HCoV 229 E (α-corona virus)
HCoV OC43 (β-corona virus)
SARS CoV (β-corona virus)
HCoV NL63 (α-corona virus)
HKU-1 (β-corona virus)
MERS CoV (β-corona virus)
SARS CoV-2 (β-corona virus)
HCoV- (Human corona virus)
MERS CoV- (Middle east
respiratory syndrome corona virus)
SARSCoV-2-(Severe acute
respiratory syndrome coronavirus-
2)
SARS CoV-2 are originated from Wuhan now it is a pandemic (spread in all
over the world )

5. structure
 Coronaviruses are large, roughly spherical, particles with bulbous surface projections.
 the average diameter of the virus particles is around 125 nm (.125 μm). The
diameter of the envelope is 85 nm and the spikes are 20 nm long. The envelope of
the virus in electron micrographs appears as a distinct pair of electron-dense shells
(shells that are relatively opaque to the electron beam used to scan the virus
particle).

6.  T he viral envelope consists of a lipid bilayer, in which the membrane (M), envelope (E)
and spike (S) structural proteins are anchored
 The coronavirus surface spikes are homotrimers of the S protein, which is composed of
an S1 and S2 subunit.
 The S1 subunit forms the head of the spike and has the receptor binding domain (RBD).
The S2 subunit forms the stem which anchors the spike in the viral envelope and on
protease activation enables fusion.
 The E and M protein are important in forming the viral envelope and maintaining
its structural shape.
Inside the envelope, there is the nucleocapsid, which is formed from multiple copies of
the nucleocapsid (N) protein, which are bound to the positive-sense single-
stranded RNA genome in a continuous beads-on-a-string type conformation. The lipid
bilayer envelope, membrane proteins, and nucleocapsid protect the virus when it is
outside the host cell.
ronaviruses contain a positive-sense, single-stranded RNA genome. The genome size for
coronaviruses ranges from 26.4 to 31.7 kilobases. The genome size is one of the largest
among RNA viruses. The genome has a 5′ methylated cap and a 3′ polyadenylated tail.

7. Replication cycle

8.  infection begins when the viral spike protein attaches to its complementary host cell
receptor. After attachment, a protease of the host cell cleaves and activates the receptor-
attached spike protein. Depending on the host cell protease available, cleavage and
activation allows the virus to enter the host cell by endocytosis or direct fusion of the viral
envelop with the host membrane.
2. Genome translation
1. Cell entry
On entry into the host cell, the virus particle is uncoated, and its genome enters the cell
cytoplasm. The coronavirus RNA genome has a 5′ methylated cap and a 3′ polyadenylated
tail, which allows the RNA to attach to the host cell's ribosome for translation. The host
ribosome translates the initial overlapping open reading frames ORF1a and ORF1b of the
virus genome into two large overlapping polyproteins, pp1a and pp1ab.
The polyproteins have their own proteases, PLpro and 3CLpro which cleave the
polyproteins at different specific sites. The cleavage of polyprotein pp1ab yields 16
nonstructural proteins (nsp1 to nsp16). Product proteins include various replication proteins
such as RNA-dependent RNA polymerase (nsp12), RNA helicase (nsp13),
and exoribonuclease (nsp14).

9. 3. Replicase-transcriptase
 The main replicase-transcriptase protein is the RNA-dependent RNA polymerase (RdRp).
It is directly involved in the replication and transcription of RNA from an RNA strand. The
other nonstructural proteins in the complex assist in the replication and transcription
process.
 Replication – One of the main functions of the complex is to replicate the viral genome.
RdRp directly mediates the synthesis of negative-sense genomic RNA from the positive-
sense genomic RNA. This is followed by the replication of positive-sense genomic RNA
from the negative-sense genomic RNA.
 Transcription – The other important function of the complex is to transcribe the viral
genome. RdRp directly mediates the synthesis of negative-sense subgenomic RNA
molecules from the positive-sense genomic RNA. This process is followed by the
transcription of these negative-sense subgenomic RNA molecules to their corresponding
positive-sense mRNAs. The subgenomic mRNAs form a "nested set" which have a common
5'-head and partially duplicate 3'-end.

11. 4. Assembly and release
The replicated positive-sense genomic RNA becomes the genome of the progeny viruses.
These mRNAs are translated by the host's ribosomes into the structural proteins and a
number of accessory proteins.
 RNA translation occurs inside the endoplasmic reticulum. The viral structural proteins S, E,
and M move along the secretory pathway into the Golgi intermediate compartment. There, the
M proteins direct most protein-protein interactions required for assembly of viruses following
its binding to the nucleocapsid.Progeny viruses are then released from the host cell
by exocytosis through secretory vesicles. Once released the viruses can infect other host cells.[
 Human coronaviruses infect the epithelial cells of the respiratory tract, while animal
coronaviruses generally infect the epithelial cells of the digestive tract. SARS
coronavirus, for example, infects via an aerosol route, the human epithelial cells of the
lungs by binding to the angiotensin-converting enzyme
2 (ACE2)receptor. Transmissible gastroenteritis coronavirus (TGEV) infects, via a
fecal-oral route,[ the pig epithelial cells of the digestive tract by binding to the alanine
aminopeptidase (APN).

12. SYMPTOMS

13. TRANSMISSION-
Sneeze, coughing , hand shaking , also be found in feces. Splitting.

14. TRANSMISSION-

15. DIAGNOSIS
Confirmation test
Samples for diagnosis
•Swabs
•Sputum
•Lavage
•Aspirates
•Serum
• rt-PCR
rt (Real time )
PCR(Polymerase chain reaction)
INCUBATION PERIOD- 4 to 21 days person should be QUARANTINE

16. Polymerase chain reaction (PCR) : is a method widely used to
rapidly make millions to billions of copies of a specific DNA sample, allowing scientists to take
a very small sample of DNA and amplify it to a large enough amount to study in detail. PCR was
invented in 1984 by the American biochemist Kary Mullisat Cetus Corporation. It is
fundamental to much of genetic testing including analysis of ancient samples of DNA and
identification of infectious agents. Using PCR, copies of very small amounts of DNA
sequences are exponentially amplified in a series of cycles of temperature changes. PCR is now
a common and often indispensable technique used in medical laboratory and clinical laboratory
research for a broad variety of applications including biomedical research and criminal forensics.

17. When a respiratory sample is collected from the person being tested it is treated with certain
chemicals which break down extraneous substances and allow the RNA to be removed from the
sample and tested. Reverse transcription polymerase chain reaction (RT-PCR) is a technique tha
first uses reverse transcription to convert the extracted RNA into DNA and then uses PCR to
amplify a piece of the resulting DNA, creating enough to be examined in order to determine if it
matches the genetic code of SARS-CoV-2.Real-time PCR (qPCR)[ provides advantages during
the PCR portion of this process, including automating it and enabling high-throughput and more
reliable instrumentation, and has become the preferred method.
These tests typically detect the amplified virus sequences using fluorescent tags which have
to be read out with specialized machines. In one new development, the CRISPR gene editing
technology was modified to detect the viral sequences instead: if the modified CRISPR
enzyme attaches to the sequence, it releases a signal which colors a paper strip. The
researchers expect the resulting test to be cheap and easy to use in patient-care setting…
COVID-19 testing can identify the SARS-CoV-2 virus and includes methods that
detect the presence of the virus itself (, RT-PCR) isothermal nucleic acid
amplification antigen and those that detect antibodies produced in response to
infection. Detection of antibodies (serological tests) can be used both for diagnosis and
for population surveillance. Antibody tests show how many people have had the disease,
including those whose symptoms were minor or who were asymptomatic, but may not
find antibodies in someone with a current COVID-19 infection since antibodies may not
show up for weeks.

18. Thermocycler
TREATMENT
Supportive care-
oVentilator support
oOxygen
oFluids
Medication-
oHydroxychloroquine 400 mg/Chloroquine
500 mg
oLoponavir 400 mg / Ritonavir 100 mg
oRemdesivir

19. PREVENTION
No vaccine is available.
Used Alcohol 60% based sanitizer.
Washing hands.
Cover mouth.
Stay home.
Avoid crowded places.
Follow social distancing.
Avoid touching nose, eyes and mouth.
Avoid travel to outbreak areas.