The Science of Covid-19

Covid-19 Explained

  • SARS-CoV-2 is the name of the virus.
  • It was first identified in Wuhan in China in December 2019.
  • The name of the disease that is associated with SARS-CoV-2 is Covid-19.
  • SARS-CoV-2 stands for Severe Acute Respiratory Syndrome Corona Virus 2.
  • The disease spread across the world and is now a Global Pandemic.
  • We now need to learn to live with and control this virus as it is now a part of our everyday lives.


Characteristics of SARS-CoV-2 Virus

  • It is a ball of genetic material with spike proteins.
  • It is the spike proteins which attach to the human cell, infecting a person with the virus.
  • These proteins attach onto the lung and cause the disease.


How is the Virus Spread

There is two ways the virus is spread:

  • Direct Contact
  • Indirect Contact


Direct Contact

  • A person infected with Covid-19 coughs or sneezes in your presence.
  • If you are not practicing safe social distancing i.e. within 2m, you can pick up the virus from them directly.
  • It is very important the 2m rule is maintained to keep yourself and others safe.
  • Face coverings and masks will also help reduce the spread of the virus physically.


Indirect Contact

  • A person who is infected with the virus coughs and sneezes into their hand and then touches an object such as door handle etc.
  • The virus is then transferred onto the surface.
  • If a non-infected person then touches the infected surface and in turn touches the nose, mouth or eyes.
  • The virus can then get into their system, attach onto the lungs and infect the person with the disease.



Signs & Symptoms of Covid-19

  • Fever
  • Cough
  • Breathlessness
  • Loss of taste and smell
  • Fatigue (in some cases extreme fatigue)

If you are suffering from any of these signs or symptoms, you should self-isolate and contact your GP and request a test immediately.


Contact Tracing

  • If you feel you have experienced any of the above symptoms you must ensure you contact trace.
  • Contact tracing log.  The HSE will request your close contacts. They will notify them and request that they self-isolate or restrict their movements and get tested themselves.


Vulnerable Groups

There are a number of vulnerable groups in society that need to be protected. These include:

  • People over the age of 70.
  • People with underlying health conditions.


Control Methods to Prevent the Spread of Covid-19

  • Virus is transmitted via physical contact – ensure physical and social distancing (2m) is being maintained and correct use of facial coverings.
  • The virus can survive on hard surfaces. Cleaning and sanitising of frequently touched objects is vital.
  • Correct hand washing and hand sanitisation is also very important. Wash for at least 20 seconds and dry them properly.
  • Work from home where possible.
  • If you do have to go into work ensure correct policies and procedures are put in place and hazard and risk assessments completed.
    • Ensure there is not too many people within the workplace at the one time.
    • Rotate the workforce.
    • Stagger start times, break times and finish times.
    • Minimise the number of people allowed in canteen at one time.
    • Ensure there is always good ventilation.
    • Avoid dark, poorly ventilated areas like elevators and lifts.
    • Avoid sharing of items e.g. pens, cups, cutlery etc.
    • If you have to share work equipment, ensure they are cleaned and sanitised after each use e.g. photocopiers and scanners.
    • Ensure all staff are trained on best practice procedures.

Covid-19 Updates

TWO NEW VARIANTS of SARS-CoV-2, the coronavirus that causes Covid-19, are spreading in Ireland.

One strain, known as B117, was confirmed Ireland on Christmas Eve and has occurred in several countries since it was first identified in the UK last month.

The most notable mutation in B117 is to the spike protein, the part of the virus that attaches onto human cells


Emerging Variants

B.1.1.7 lineage (a.k.a. 20I/501Y.V1 Variant of Concern (VOC) 202012/01)

  • This variant has a mutation in the receptor binding domain (RBD) of the spike protein at position 501, where amino acid asparagine (N) has been replaced with tyrosine (Y). The shorthand for this mutation is N501Y. This variant also has several other mutations, including:
    • 69/70 deletion: occurred spontaneously many times and likely leads to a conformational change in the spike protein
    • P681H: near the S1/S2 furin cleavage site, a site with high variability in coronaviruses. This mutation has also emerged spontaneously multiple times.
    • ORF8 stop codon (Q27stop): mutation in ORF8, the function of which is unknown.
  • This variant is estimated to have first emerged in the UK during September 2020.
  • Since December 20, 2020, several countries have reported cases of the B.1.1.7 lineage, including the United States and Canada.
  • This variant is associated with increased transmissibility (i.e., more efficient and rapid transmission).
  • Currently there is no evidence to suggest that the variant has any impact on the severity of disease or vaccine efficacy.

B.1.351 lineage (a.k.a. 20H/501Y.V2)

  • This variant has multiple mutations in the spike protein, including K417T, E484K, N501Y. Unlike the B.1.1.7 lineage detected in the UK this variant does not contain the deletion at 69/70.
  • This variant was first identified in Nelson Mandela Bay, South Africa, in samples dating back to the beginning of October 2020, and cases have since been detected outside of South Africa.
  • The variant also was identified in Zambia in late December 2020, at which time it appeared to be the predominant variant in the country.
  • Currently there is no evidence to suggest that this variant has any impact on disease severity.
  • There is some evidence to indicate that one of the spike protein mutations, E484K, may affect neutralization by some polyclonal and monoclonal antibodies.

P.1 lineage (a.k.a. 20J/501Y.V3)

  • The P.1 variant is a branch off the B.1.1.28 lineage that was first reported by the National Institute of Infectious Diseases (NIID) in Japan in four travelers from Brazil, sampled during routine screening at Haneda airport outside Tokyo.
  • The P.1 lineage contains 17 unique amino acid changes and 3 deletions.
  • This variant contains three mutations in the spike protein receptor binding domain: K417T, E484K, and N501Y.
  • There is evidence to suggest that some of the mutations in the P.1 variant may affect its transmissibility and antigenic profile, which may affect the ability of antibodies generated through a previous natural infection or through vaccination to recognize and neutralize the virus.
    • A recent study reported on a cluster of cases in Manaus, the largest city in the Amazon region, in which the P.1 variant was identified in 42% of the specimens sequenced from late December. In this region, it is estimated that approximately 75% of the population had been infected with SARS-CoV2 as of October 2020. However, since mid-December the region has observed a surge in cases. The emergence of this variant raises concerns of a potential increase in transmissibility or propensity for SARS-CoV-2 re-infection of individuals.


Evidence suggests that these strains are far more transmissible than other variants of SARS-CoV-2.

Health officials now estimate that a quarter of new cases of the illness in Ireland are due to the UK strain (B117), which may be one factor in record case figures and hospitalisations set this week.

In order to Stop the spread of Covid-19,

It is important that you:

  • wash your hands properly and often
  • practice social distancing
  • cover coughs and sneezes
  • Wear a clean mask
  • Stay at Home if you feel sick or have any symptoms of Covid-19
  • Work from home as much as possible and Limit your social contacts
  • follow the current Government restrictions