Three-in-one, A Short Essay on Coronavirus for School Kids – a post-on-demand – takes on viruses in general and SARS-CoV-2 in particular apart from COVID-19, the pandemic.
What is Coronavirus?
Coronavirus is a virus, but not a single virus. Coronaviruses, in fact, form a large family of viruses that may cause flu-like symptoms in humans and other illnesses in animals. A new strain of them has caused the ongoing pandemic COVID-19. Other species of them were behind SARS and MERS.
Coronaviruses are so named due to the protruding spikes of protein that give to them a halo-like the solar corona. The official name of the present virus is SARS-CoV-2 (Severe Acute Respiratory Syndrome-related Coronavirus-2). The initial name was 2019-nCoV, the letter ‘n’ standing for ‘novel’ meaning ‘new’.
Taxonomy of SARS-CoV-2
- Realm: Riboviria
- Kingdom: Orthornavirae
- Phylum: Pisuviricota
- Class: Pisoniviricetes
- Order: Nidovirales
- Family: Coronaviridae
- Genus: Betacoronavirus
- Species: Severe acute respiratory syndrome-related coronavirus
Clearly, a “realm” is the highest taxonomic rank into which we classify viruses. A total of 6591 virus species are classified so far by the International Committee on Taxonomy of Viruses. The ICTV is a committee of the International Union of Microbiological Societies. They are authorized for taxonomic positioning of the viruses.
How many Coronaviruses are there?
We classify coronaviruses into four genera: α-alpha, β-beta, γ-gamma and δ-delta. Together, the coronaviruses number at least 45. There are 14 β-coronaviruses themselves, SARS-CoV-2 being the latest or the 14th one. Thus, taxonomically we can define coronaviruses as viruses belonging to the family Coronaviridae. Students should acquaint themselves down the family at least.
What are viruses?
So much for the coronavirus. Going back to the roots, what are viruses? Simply put, viruses are very tiny germs – made of genetic material inside a protein coating. They are smaller than bacteria. They need living hosts like plants, animals and humans to multiply. Otherwise, they are as good as being dead or non-living.
Viruses, as such, are obligatory intracellular pathogens. They have too small a genome size to live and reproduce on their own. They are in a sense the link between the non-living and the living domains.
Types of Viruses
Since the viruses are little more than nucleic acid, we group them on the basis of the nucleic acid. So, we have DNA and RNA viruses. Now, the former viruses are usually double‐stranded DNA (dsDNA) and rarely single‐stranded DNA (ssDNA). RNA viruses have typically ssRNA but may also contain dsRNA. ssRNA viruses can be further grouped as positive‐sense (+ssRNA) or negative‐sense (−ssRNA).
Compared to DNA virus genomes, which can encode up to hundreds of viral proteins, RNA viruses have smaller genomes that usually encode only a few proteins. DNA and RNA viruses have developed some distinct infection strategies to cause generally chronic and acute infections, respectively. The present virus SARS-CoV-2 is an RNA virus.
The current antiviral therapeutics is based on inhibiting specific viral proteins, e.g. essential viral enzymes. Unfortunately, this approach is ineffective as viruses develop drug resistance through mutation. To note, especially the RNA viruses mutate very rapidly.
Clearly, SARS-CoV-2 is difficult to tame as it is an RNA virus. The pandemic enemy is not exactly the same all over the globe. Perhaps now is the time to focus on the specific pathogen-targeted host proteins instead of targeting pathogen proteins themselves. Serious senior students may access more technical material here.
What is COVID-19?
COVID-19 is the name of the disease that this virus causes. The name stands for ‘Coronavirus Disease’. The number ’19’ has nothing to do with the genetics of the virus. It stands for 2019 signifying the year of origin.
To repeat, coronaviruses are a family of viruses; SARS-CoV-2 is the present virus, and COVID-19 is the name of the present pandemic disease. Moreover, it is a zoonotic disease as the pathogen jumps from animals to humans.
What are the symptoms of COVID-19?
Most common symptoms are dry cough, fever, and tiredness. Some patients may show other symptoms like aches and pains, nasal congestion, headache, conjunctivitis, sore throat, diarrhoea, loss of taste or smell, a rash on skin or discolouration of fingers or toes.
Who needs hospitalisation?
Shortness of breath or difficulty in breathing is the severe symptom warranting hospitalisation. However, this happens in the case of only about 20% of patients. In fact, most of the patients are asymptomatic. They show no or very mild symptoms. Moreover, the symptoms match the common cold symptoms. All these factors in combination make the scenario alarming as the disease is highly contagious.
What is the recovery rate?
The fatality rate being around 5%, chances of recovery are statistically high. Moreover, only patients of old age and/or with co-morbidities (having other serious illnesses) succumb to death. Also, compared to women, men are more prone to infection.
How is it a pandemic, then?
First, COVID-19 is highly contagious. Secondly, asymptomatic patients also spread the disease. Thirdly, the virus spreads merely by coughing of the infected person – worse still, even by touching and talking.
What is the line of treatment?
Viruses actually respond only to suitable vaccines which are preventive in nature. Antibiotics aren’t effective against viral diseases. Essentially, with viral infections treatments only help alleviate symptoms while we wait for the body’s immunity to fight off the virus. Nonetheless, severe patients need life-supportive treatment in the form of oxygen and ventilators.
Several medicines have been tried but none is yet officially approved and recommended. These include medicines given to malaria and HIV patients. A vaccine is the only hope of mankind. A very good number of researches are going on. Still, we don’t see an approved vaccine is anywhere near. The reason lies in the nature and type of the virus.
So, how to avoid getting infected?
With SARS-CoV-2, prevention is the only cure. Social distancing is of utmost importance. Develop a habit of frequent, regular and proper handwashing. Wear a mask. Don’t panic. And, be alert of fake news and disinformation.
Some of the myths doing the rounds are these. One, thermal scanners can detect COVID-19. – No, they cannot; they just identify fast if you have a fever without actually touching the body. Two, the prolonged use of medical masks may causet cause CO2 intoxication or oxygen deficiency. – No, they don’t when worn properly. Three, drinking alcohol may protect against COVID-19. – No, it doesn’t. On the contrary, it can be harmful indeed. Four, COVID-19 is extremely fatal. – No, it is more contagious than it is fatal. The fatality rate is around 5% and most people who get COVID-19 recover from it. And, most importantly, don’t worship the coronavirus. With the virus, it doesn’t pay to be religious.
Authentic COVID-19 Resources Online
- John Hopkins University Resource Centre
- WHO Questions & Answers Hub