2. INTRODUCTION
▪ Virus, infectious agent of small size and simple composition that can multiply only in
living cells of animals, plants, or bacteria. The name is from a Latin word meaning “slimy
liquid” or “poison.”
▪ Viruses occupy a special taxonomic position: they are not plants, animals,
or prokaryotic bacteria (single-cell organisms without defined nuclei), and they are
generally placed in their own kingdom. In fact, viruses should not even be considered
organisms, in the strictest sense, because they are not free-living—i.e., they cannot
reproduce and carry on metabolic processes without a host cell.
3. At the end of 2019, a series of pneumonia cases of unknown cause emerged in Wuhan (Hubei,
China). A few weeks later, in January 2020, deep sequencing analysis from lower respiratory tract
samples identified a novel virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as
causative agent for that observed pneumonia cluster.
On February 11th, 2020, the World Health Organization (WHO) Director-General, Dr. Tedros
Adhanom Ghebreyesus, named the disease caused by the SARS-CoV-2 as “COVID-19”, and by March
11th, 2020 when the number of countries involvedwas 114, with more than 118,000 cases and
over 4000 deaths, the WHO declared the pandemic status
4. General information on the virus
▪ Coronaviruses are a group of related viruse that cause diseases in mammals and birds In humans, coronaviruses
cause respiratory tract infections that can range from mild to lethal. Mild illnesses include some cases of
the common cold (which has other possible causes, predominantly rhinoviruses), while more lethal varieties can
cause SARS, MERS, and COVID-19
▪ Coronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales, and
realm Riboviria. They are enveloped viruses with a positive-sense single-stranded RNA genome and
a nucleocapsid of helical symmetry. The genome size of coronaviruses ranges from approximately 26 to
32 kilobases, one of the largest among RNA viruses. They have characteristic club-shaped spikes that project
from their surface, which in electron micrographs create an image reminiscent of the so corona from which their
name derives.
5. STRUCTURE
▪ Coronaviruses are large pleomorphic spherical particles with bulbous surface
projections.The average diameter of the virus particles is around 120 nm(.12 μm).
The diameter of the envelope is ~80 nm (.08 μm) and the spike are ~20 nm (.02
μm) long. The envelope of the virus in electron micrographs appears as a distinct pair
of electron dense shells.
▪ The viral envelop consists of a lipid bilayer where the membrane (M), envelope € and
spike (S) structural proteins are anchored. A subset of coronaviruses (specifically the
members of beta coronavirus subgroup A also have a shorter spike-like surface
protein called hemagglutinin esterase (HE)
▪ 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-strin type conformation. The lipid
bilayer envelope, membrane proteins, and nucleocapsid protect the virus when it is
outside the host cell.
6. STRUCTURE
Illustration of the morphology of
coronaviruses; the club-shaped viral spike
peplomers, colored red, create the look of
a corona surrounding the virion when
observed with an electron microscope
9. DIAGNOSIS
For patients with suspected infection, the following diagnosis techniques are utilised:
performing real-time fluorescence (RT-PCR) to detect the positive nucleic acid of SARS-CoV-
2 in sputum, throat swabs, and secretions of the lower respiratory tract samples.
In patients with COVID-19, the white blood cell count can vary. Leukopenia, leukocytosis,
and lymphopenia have been reported, although lymphopenia appears most common
Elevated lactate dehydrogenase and ferritin levels are common, and elevated
aminotransferase levels have also been described.
10. Management
There is no specific antiviral treatment recommended for COVID-19, and no vaccine is currently
available. The treatment is symptomatic, and oxygen therapy represents the major treatment
intervention for patients with severe infection. Mechanical ventilation may be necessary in cases
of respiratory failure refractory to oxygen therapy, whereas hemodynamic support is essential for
managing septic shock.
Different strategies can be used depending on the severity of the patient
and local epidemiology. Home management is appropriate for asymptomatic or paucisymptomatic
patients. They need a daily assessment of body temperature, blood pressure, oxygen saturation and
respiratory symptoms for about 14 days.
11. Management of such patients should focus on prevention of transmission to others and
monitoring for clinical status with prompt hospitalization if needed. They should wear a
face mask when in the same room (or vehicle) as other people and when presenting to
health care settings. Disinfection of frequently touched surfaces is also important
Outpatients with COVID-19 should stay at home and try to separate themselves from other
people in the household. On admission, many patients with pneumonia have normal serum
procalcitonin levels; however, in those requiring ICU care, they are more likely to be
elevated. High D-dimer levels and more severe lymphopenia have been associated with
mortality. Imaging findings—Chest computed tomography (CT) in patients with COVID-19
most commonly demonstrates ground-glass opacification with or without consolidative
abnormalities,
12. Management ContinuedChloroquine and hydroxychloroquine have antiviral activity in vitro, as well as anti-
inflammatory activities.
They act on interference with the cellular receptor ACE2, on impairment of acidification of
endosomes and on activity against many pro-inflammatory cytokines (e.g., IL-1 and IL-6)
Tocilizumab is a recombinant humanized monoclonal antibody which binds to the
interleukin-6 (IL-6) receptor and blocks it from functioning.
It is used for patients with severe COVID-19 and elevated IL-6 levels; the agent is being
evaluated in a clinical trial
13.
14. Prevention of COVID 19
• Clean your hands often. Use soap
and water, or an alcohol-based
hand rub.
• Maintain a safe distance from
anyone who is coughing or
sneezing.
• Don’t touch your eyes, nose or
mouth.
• Cover your nose and mouth with
your bent elbow or a tissue when
you cough or sneeze.
• Stay home if you feel unwell.
• If you have a fever, a cough, and
difficulty breathing, seek medical
attention. Call in advance.
• Follow the directions of your local
health authority.
16. Conclusion
▪ As there is no proper treatment and vaccine for COVID 19 it is
advisable to stay home and stay safe. Together we can and we will
conquer this pandemic by cooperating with the Government of
respective countries by avoiding social gatherings.
▪ Use Masks, and sanitizers while going out to by groceries,
medicines, etc.
▪ And most importantly avoid hand shakes and maintain social
distancing.
THERE’S NOTHING TO FEAR FOLLOW THESE THINGS AND SPEND
QUALITY TIME WITH FAMILY AND LOVED ONES
