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A SHORT REVIEW ON CORONA VIRUSE DISEASE (COVID - 2019)
Roshani Shetye* and Hrishikesh Shelar
Assistant Professor Ms. Kanchan Dasharath, Shree Saraswati Institute of Pharmacy, Tondavali
Dist- Sindhudurg.
ABSTRACT
The coronavirus pandemic pits all of the humanity against the virus. In
late December 2019, chinese health authorities reported an outbreak of
pneumonia of unknown origin in Wuhan, Hubel province. These viruses
contain spike like projection of glycoprotein on their surface, hence they
are referred to as coronavirus. There genome encodes several structural
and nonstructural proteins. The structural proteins are responsible for host
infection, membrane fusion, viral assembly, morphogenesis and release
of virus particles whereas the nonstructural proteins facilitate viral
replication and transcription. SARS-COV-2 is a member of large family
of viruses called coronavirus. As with SARS and MERS is believed to
be of zoonotic origin, but may also transmitted through the respiratory
tract, direct contact and possibly via patient excreta which may contain the
living virus. Protection from COVID-19 is critically important because for some people, COVID-
19 can cause severe illness or death. Vaccines work with your immune system so your body
will be ready to fight the virus if you are exposed.
KEYWORDS: Coronavirus, glycoprotein, SARS-COV-2, vaccine.
INTRODUCTION
World Journal of Pharmaceutical Research SJIF Impact Factor 8.084
Volume 10, Issue 6, 837-849. Review Article ISSN 2277– 7105
*Corresponding Author
Roshani Shetye
Assistant Professor Ms.
Kanchan Dasharath, Shree
Saraswati Institute of
Pharmacy, Tondavali Dist-
Sindhudurg.
Article Received on
16 April 2021,
Revised on 06 May 2021,
Accepted on 27 May 2021
DOI: 10.20959/wjpr20216-20640
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Coronaviruses are a large family of viruses that are known to cause illness ranging from the
common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS)
and Severe Acute Respiratory Syndrome (SARS). A novel coronavirus (COVID-19) was
identified in 2019 in Wuhan, China. This is a new coronavirus that has not been previously
identified in humans. Coronaviruses got their name from the way that they look under a
microscope. The virus consists of a core of genetic material surrounded by an envelope with
protein spikes. This gives it the appearance of a crown. The word Corona means “crown” in
Latin.
On 31 December 2019, WHO was informed of cases of pneumonia of unknown cause in
Wuhan City, China. A novel coronavirus was identified as the cause by Chinese authorities on
7 January 2020 and was temporarily named “2019-nCoV”.On 30 January 2020, Dr Tedros
Adhanom Ghebreyesus, WHO Director-General declared the novel coronavirus outbreak a
public health emergency of international concern (PHEIC), WHO's highest level of alarm. At
that time there were 98 cases and no deaths in 18 countries outside China.By mid-March
2020, the WHO European Region had become the epicentre of the epidemic, reporting over
40% of globally confirmed cases. As of 28 April 2020, 63% of global mortality from the
virus was from the Region.The world’s most affected economies due to coronavirus are the
European Union, the US, Japan, South Korea, Taiwan, and Vietnam, according to
UNCTAD’s preliminary estimates of trade impact.
The virus that causes COVID-19 is thought to have originated in bats and then spread to snakes
and pangolins and hence to humans, perhaps by contamination of meat from wild animals,
as sold in China’s meat markets.
Human corona viruse types
Six species of human coronaviruses are known, with one species subdivided into two
different strains, making seven strains of human coronaviruses altogether.
• Human coronavirus 229E (alpha)
• Human coronavirus NL63(alpha)
• Human coronavirus OC43(beta)
• Human coronavirus HKU1(beta)
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Three human coronaviruses produce potentially severe symptoms
• Severe acute respiratory syndrome coronavirus (SARS-CoV), β-CoV (identified in 2003)
• Middle East respiratory syndrome-related coronavirus (MERS-CoV), β-CoV (identified in
2012)
• Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), β-CoV (identified in
2019)
Common structure of corona virus
(A) Coronavirus genome includes 5′ untranslated region (5UTR), such as 5′ leader sequence,
open reading frame (ORF) 1a/b encoding non-structural proteins (nsp) for replication,
structural proteins such as envelop, membrane and nucleoprotein, accessory proteins.
(B) SARS-COV-2 encodes two large polyproteins, pp1a and pp1ab, that are cleaved into 16
non-structural proteins.
(C) The coronavirus contains a + sense single stranded RNA (ssRNA) genome encapsidated
by the nucleocapsid (N) protein, with the spike (S), membrane (M), and envelope (E)
proteins located on the outside of the membrane.
Transmission
It is believed that viruses that causes covid-19 spread mainly from person to person. There are
several ways that can happen.
• Droplets or aerosols
• Airborne transmission
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• Surface transmission
• Fecal- oral
The routes of transmission of COVID-19 remains unclear at present, but evidence from other
coronaviruses and respiratory diseases indicates that the disease may spread through large
respiratory droplets and direct or indirect contact with infected secretions.
Mechanism by which coronavirus infection occur and it's mode of replication
Contagious respiratory diseases that has caused pandemic, such as flu (e.g swine flu in 2009)
SARS 2002, MERS 2009, covid-19 have similar symptoms, although these diseases are
caused by different viruses and have different infection mechanisms. For comparison, the
mechanism by which infection with the influenza virus occur and replicate has the following
main steps.
1. Binding influenza virus with cell receptor ( adsorption)
2. Penetration of the influenza virus into the cell (endocytosis)
3. Fusion with endosome(nuclear entry)
4. Transcription, transition and replication of viral genome segment and
5. The release of free nucleocapsid into cytoplasm ( fusion sites)
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As a result, it is necessary to test the effect of these disease by different method, firstlyto confirm
the diagnosis, and secondly to detect the viral nucleic acid, specific viral protection or virions of
human corona virus (HCoV), the newest and most deadly one, the 2019- nCoV(SARS-CoV-2)
viruses.
Epidemiology
The frequency of characteristics of cases where describe by age, gender, residence, time of
exposure (contact and travel), and symptoms. The presence of any symptoms at the time of
specimen collection was used to draw epidemic curve. The time tread where annotated with that
of implementation of various public health measure and key events related to that epidemic. A
epidemiological study by Laxminarayan et al, published in Science, shows there was limited
incidence of the disease and mortality among older adults (aged more than 65 years) in Tamil
Nadu and Andhra Pradesh, in sharp contrast to the situation in the US. The first case in India
was detected on January 30. Even as the outbreak expanded quickly in Europe and USA, it
picked up slowly in India due to stringent lockdowns imposed since March 25. But now there
are about 6.2 million confirmed cases in India, second only to the USA at 7.4 million cases.
Given that India is now adding about 83,000 cases daily compared to 42,800 for the USA, it
may have most Covid-19 cases within a few weeks.
Reasonable estimates, including a seroprevalence study released by ICMR on September 29,
suggest that about 100 million people may have already been infected. But the associated
mortality remains low, with 97,500 confirmed deaths and a case fatality rate (CFR) of about 1.6%,
although both deaths and cases are likely to be severely underestimated. The mortality figures for
India mirror similar numbers across other parts of South Asia, which is home to about 25% of
the world’s population and has 20% of global COVID-19 cases, but only 10% of mortality.
Different countries show different rates and modes of transmission, due to factors such as
varying population density, differential adherence to public health measures, variations in testing
and contact tracing, and the under-reporting of mortality. LMIC populations are typically younger,
and thus at lower risk of severe infection and mortality. However, the presence of poorer
healthcare infrastructure and nutrition, pre-existing conditions and prior exposure to other
infectious diseases make the relationship between pandemic control and health policy complex
and unpredictable.
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Sign and symptoms
The most common symptoms of COVID-19 are
• Fever
• Dry cough
• Fatigue
Symptoms of severe COVID‐19 disease include
• Shortness of breath,
• Loss of appetite,
• Confusion,
• Persistent pain or pressure in the chest,
• High temperature (above 38 °C).
• delirium and nerve damage.
Treatment
A) Aurvedic
B) Allopathic
A) Ayurvedic
This is the first known case of a Coronavirus disease (COVID-19) positive patient treated
entirely with Ayurveda. So far in Modern Western Medicine (MWM), no cure has been found
which is specific to COVID-19. The only literature relevant to the treatment of Coronavirus
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disease has surfaced from Traditional Chinese Medicine (TCM). TCM which was extensively
used to control the epidemic in China, also consists of herbal medicines similar to Ayurveda. In
this case, the patient, who was familiar with the use of Ayurvedic medicines, fully aware that no
proven cure exists in MWM, decided to entirely rely on the limited Ayurvedic medicines that he
had in his possession at the time of falling ill.
General Measures for enhancing immunity and fitness of mind and body
• Drink warm water throughout the day.
• Do Pranayama [deep breathing exercise] daily
• Practice Yoga for at least 30 minutes daily
• Meditate daily
• Include Turmeric (Curcumin), Cumin, Coriander and Garlic in dishes.
• Ayurvedic drink for immunity
• Drink herbal tea made with Holy Basil, Cinnamon, Black pepper, Dry Ginger and Raisin –
once or twice a day.
• Add jaggery (natural sugar) and / or fresh lemon juice as per your taste, if needed.
• Those who are used to consuming milk regularly, can mix half tea spoon turmeric powder
in
• 150 ml hot milk and take once or twice a day.
Ayurvedic herbal medicine for Immunity and Strength
• Chyavanprash 10gm in the morning. [Diabetics can take sugar free Chyavanprash]
Simple Ayurvedic treatment that improve oral and nasal health and immunity
• Nasal application – Instill 2 drops of sesame oil / coconut oil / Ghee in both the nostrils in
morning.
• Oil pulling therapy – Take 1 table spoon sesame or coconut oil in mouth.
• Do not drink, Swish in the mouth for 2 to 3 minutes and spit it off followed by warm water
rinse.
• This can be done once or twice a day.
• Steam inhalation with fresh Mint leaves or Caraway seeds can be practiced once in a day.
• Clove powder mixed with natural sugar / honey can be taken 2-3 times a day in case of cough
or throat irritation.
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Allopathic treatment
In the allopathic medical systems, the Chloroquine is used as a salt namely Chloroquine
sulphate (salt of Cinchona Bark), while in the homeopathic medical system, the mother tincture
of cinchona bark and its potencies are used. Moreover, homeopathic mother tinctures and
potencies are much cheaper than Chloroquine Sulphate.
Why “Cinchona” should be used in place of Chloroquine?
There are many side effects of using Chloroquine. For instance, Braga, et reported that although
antimalarial drugs (Chloroquine and Primaquine) are helpful to treat patients infected with vivax
malaria, at the same time these drugs cause several adverse effects mainly related to
gastrointestinal leading to nonadherence of drug treatment. The authors further reported that these
drugs also reduce the lack of appetite along with blurred vision, pruritus, insomnia, etc. Whereas,
there is not any side effect reported by any scholar/patient or doctor/physician who used china off
in a homeopathic way.
The symptoms of COVID-19 are the same as compared to Cinchona Off symptoms.
Role of Zinc to enhance the immune system
It has been very well reported that the persons with the low immune system are more vulnerable
to get infected with COVID-19. Hence, it is necessary to pay more attention to enhancing the
immune system of patients infected with COVID-19. It has been reported that Zinc deficiency
depresses both innate and adaptive immune responses, and it also plays an important role to
enhance the immune system. Furthermore, Khanam, also reported that Zinc plays an important
role in boosting the immune system by keeping the immune system strong.
Interaction of Chloroquine with Zinc
It has been reported that Zn2+ prevents coronaviruses and arterivirus RNA polymerase
activity in vitro and zinc ionophores obstruct the replication of coronaviruses. Furthermore,
Chloroquine along with Zinc has also been reported to treat COVID-19 infected patients. For
instance, Xue, examined the effect of zinc ions along-with Chloroquine in cancer cell lines (a
human ovarian) (A2780). The authors found that Chloroquine boosted zinc uptake by A2780
cells, as tested through a fluorescent zinc probe. The authors further reported that the blend of
Chloroquine and zinc increases the cytotoxicity of Chloroquine and tempted apoptosis in
A2780 cells. Hence, both drugs are very helpful to enhance immunity and treat coronaviruses
successfully.
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About the vaccine
The second phase of the COVID-19 vaccination drive has already begun in India, and many
people are still unaware of how the two vaccines – Covaxin and Covishield – are different
from each other. The second phase began on March 1, in which people over the age of 60 and
those above 45 with associated comorbidities can take the life-saving shots.
Covaxin: Covaxin is an inactivated vaccine, which has been prepared on a tried and tested
platform of dead viruses. This vaccine is developed with Whole-Virion Inactivated Vero
Cell-derived technology. They contain inactivated viruses, which can not infect a person but
still can teach the immune system to prepare a defence mechanism against the active virus.
These conventional vaccines have been in use for decades now.
There are vaccines for some other diseases as well which are made using the same
technology. These diseases are.
• Seasonal influenza
• Rabies
• Polio
• Pertussis, and
• Japanese encephalitis
Covishield: Covishield has been prepared using the viral vector platform which is a totally
different technology. A chimpanzee adenovirus – ChAdOx1 – has been modified to enable
it to carry the COVID-19 spike protein into the cells of humans. Well, this cold virus is
basically incapable of infecting the receiver but can very well teach the immune system to
prepare a mechanism against such viruses. The exact technology was used to prepare vaccines
for viruses like Ebola.
Vaccination statistics
From our world in data
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This data shows how many people have reviewed dose of vaccine.
Precautions about Coronavirus disease
If COVID-19 is spreading in your community, stay safe by taking some simple precautions,
such as physical distancing, wearing a mask, keeping rooms well ventilated, avoiding
crowds, cleaning your hands, and coughing into a bent elbow or tissue. Check local advice
where you live and work.
To prevent the spread 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.
• Wear a mask when physical distancing is not possible.
• 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, cough and difficulty breathing, seek medical attention.
• Avoid public transport that is crowded and carry tissues to cover your mouth when you
cough or sneeze. Put used tissues only inside dustbins, don’t throw them outside.
• Avoid travelling altogether if you're showing symptoms like cough, fever, or cold. Wear
face masks in crowded regions, don't touch your mask with your hands once you've put it
on.
• If you live in a region that has reported cases of COVID-19, consider wearing a Facemask
before heading out. A face mask gives you basic protection against airborne germs and
infections.
There is always the threat of silent transmission of illnesses, and no estimate is present as to
when a COVID-19 cure will be found. However, by staying hygienic and following simple
steps like washing your hands, you would be doing your best to keep yourself and your family
safe.
CONCLUSION
Continues to spread across the world following a trajectory that is difficult to predict. The
health, humanitarian and socio-economic policies adopted by countries will determine the
speed and strength of the recovery. The ILO’s four pillar policy framework presented in this
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brief provides guidance not only for countries as they progress through the various phases of
the crisis, but also for the international community as a whole. There must be a global human-
centred response which is grounded in solidarity.
Covid-19 viral spectre outbreak is spreading across different countries at an increasingly
alarming rate. It requires a more focused approach on preventive measures and identification
of high-risk factors such as extremes of age group and comorbidity. Precautionary measures
such as compulsory practise of social distancing, self-isolation, usage of personal protective
equipment, adequate hand hygiene along with respiratory hygiene and effective quarantining are
required right now to prevent further community transmission.
Proper screening by early detection of contacts, self-monitoring of travellers travelling from
affected areas, creating awareness among the population about signs and symptoms of the
disease, and promoting people to self-reportwill aid in the effective management of the spread
of coronavirus. It will further help in curbing the current devastating scenario.
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