The beginning of 2020 brought a medical crisis that baffled scientists and doctors to date. It was the novel Coronavirus or Covid-19. The virus was unknown in human beings, and hence its severity, effect, transmission, ways to beat it had the scientific and the medical community at a complete loss.
This blog will cover the various aspects of the Covid pandemic, throwing light on what has been discovered in its course of evolution in the past two years.
Shades Of Covid
|The type of virus||Coronavirus or Covid-19 or 2019-nCoV is caused by the virus SARS-CoV-2 (Severe Acute Respiratory syndrome Coronavirus 2).It is an RNA-enveloped single-stranded virus. Coronaviruses or CoV is a virus family responsible for causing diseases like the common cold.Covid-19 is a novel strain of Coronavirus and was not discovered in human beings before this.There are four genera of CoVs. These are alpha-, beta-, gamma- and delta-CoV. The alpha- and beta- Covidviruses are known to infect human beings. Some of the genera of CoVs are known to infect animals – for example, the SARS-CoV of 2002 is a virus that infects civet cats. Or, the MERS-CoV is a virus attacking dromedary camels which were later passed onto human beings in 2012. The novel Coronavirus is a zoonotic virus – a virus that is passed from an animal to a human being.SARS-CoV-2 is a genetically-related virus isolated from bats. The source of this virus type is still unknown. Appearance The SARS-Cov-2 is characterized by a crown-like feature called c Latin, noticeable under an electron microscope. The crown-like shape appears due to the spike glycoproteins present on the envelope. Detection of SARS-CoV-2An advanced sequencing approach based on RNA metagenomic is applied to detect the virus’s entire genome.The genome is 29,881 bp in length. It has 9860 encoded amino acids with structural and non-structural proteins.The structural proteins are the S, E, M, and N genes. The non-structural proteins are RNA-dependent RNA polymerase, papain-like protease, and 3-chymotrypsin-like protease.|
|Variants of Covid-19||There are now five known variants of SARS-CoV-2. The first is the Alpha variant or alphaCoV or B.1.1.7. It is famously known as the UK variant.The Beta variant or betaCoV or B.1.351 is also known as the South Africa variant. This variant has five sub-genera. The Gamma variant or gammaCoV or P.1 is also known as the Brazil variant.The Delta variant or deltaCoV or B.1.617.2 is called the India variant.The Covid-19 VirusOmicron or Omicron variant or B.1.1.529 was detected for the first time in South Africa in November 2021. It is rapidly spreading across the world.Genome sequencing shows that the alphaCoV and betaCoV are present in bats and rodents. The deltaCoV and gammaCoV are present in Avian species|
|History of Covid||In December 2019, the World Health Organization (WHO) was updated about an unknown form of pneumonia spreading fast in Wuhan City in China.Researches later revealed that the initial cases were linked to the Huanan Wholesale Seafood Market located in Wuhan City. This market is one of the regional markets where all animal species are sold, including domesticated animals, wild animals, and seafood.As a result, the initial patients mainly were sellers, shop owners, and regular buyers. Detailed study of environmental samples collected from the market in December 2019 confirmed that this market was the outbreak’s origin. As per WHO, the first possible date of this outbreak is thought to be 8th December 2019.In January 2020, the Chinese government identified the source of the disease as a strain of Coronavirus. By 20th January 2020, the WHO and the Chinese government established that the virus spreads human-to-human. By mid-January 2020, the virus had already spread to many other provinces in China. By 24th January 2020, health workers in China were advised to use personal protective equipment while treating patients.On 30th January 2020, the WHO Director-General termed nCoV as a ‘Public Health Emergency of International Concern.’Meanwhile, the virus had spread to eighteen countries, and there was no death recorded outside of China.By 11th March 2020, the worldwide outbreak of the virus was termed a pandemic by the WHO chief. Meanwhile, the virus had spread to 114 countries with approx. 4291 deaths globally.By 19th March 2020, Italy became the epicenter of the outbreak. By 26th March 2020, the US was at the top of the list with the most confirmed Covid-19 cases.|
|Color codes used in specific areas||All countries have used color coding to identify hotspots and regions of high-risk, low-risk, or no-risk zones.Red indicates countries or regions with a high risk of infection.Orange indicates areas or nations where the risk of infection is moderate.Green indicates a geographical region with either low risk or no risk of infection.|
- What is the Delta variant?
The Delta variant or B.1.617.2 was classified as a variant of concern by WHO in May 2021. The variant transmits faster than the Alpha and the Beta variants. This particular variant was responsible for innumerable deaths worldwide in 2021. It has 13 mutations that alter the sequence of amino acids when encoding.
2. What is the history of the Delta variant of the Novel Coronavirus?
The Delta variant was detected and reported for the first time in India in mid-2020. It was officially termed Delta on 31st May 2021. By June 2021, the variant was declared by WHO as the most dominant strain globally. And, by 22nd November 2021, the variant had spread to more than 179 countries and more.
The spike protein gene encoding of the variant is mainly responsible for the mutation of the Delta variant. In June 2021, the WHO said that this variant of concern is a highly transmissible disease with decreased neutralization. The second wave in India was due to this variant. It also was responsible for the third wave in the UK, South Africa, and Fiji. Besides these countries, the US, parts of Asia, New Zealand, and Australia also suffered blows from this deadly variant.
3. What is the Covid-19 VirusOmicron?
Coronavirus gets transmitted from human to human. It evolves and undergoes mutations so that the new variant is entirely different from the original virus. The Omicron or B.1.1.529 was reported for the first time by WHO on 24th November 2021. Two days later, the WHO published the variant as one of concern based on the recommendation made by the Technical Advisory Group on Virus Evolution. Information about the variant first came in from South Africa.
4. What do we know about mutations of the Covid-19 VirusOmicron variant?
As mentioned by the WHO, Omicron has multiple mutations, which is the leading cause of concern. Compared to other viruses of concern (VOC), this variant has been found to carry an increased risk of reinfection. Since not much data is available about the variant, WHO has instructed member countries to increase genome sequencing efforts and submit the metadata to medical databases for further studies.
5. What organs does SARS-CoV-2 affect?
The virus family primarily affects the respiratory, neurology, enteric, and hepatic organs of living beings, bats, cats, camels, and cattle.