Tag Archives: Coronavirus

VIRUSES – WHAT EXACTLY ARE THEY?

We keep hearing talk of the Coronavirus or Covid-19 but what exactly are viruses and why are they so problematic?

Prokaryotes

In the simplest of terms, viruses are what scientists call prokaryotes – single-celled organisms that don’t have a nucleus.  (A nucleus is the ‘brain’ of a cell, it controls the activities that take place within that cell.). There is much debate within the scientific community whether viruses should be treated as living organisms because they are dormant when they do not have a host in which to live.  Some viruses can remain dormant for thousands of years, if the conditions are right.  When I say they remain dormant, I mean that they cannot reproduce or feed or carry out any other metabolic process without a host.  

Genetic material

Viruses contain either DNA or RNA as their genetic material.  In humans and other mammals, the genetic material is a double helix of DNA.  In fact, the vast majority of organisms contain DNA as their genetic material.  Diseases such as Smallpox and Chickenpox are spread by DNA viruses.

Other viruses, such as the Coronaviruses and Rabies, are RNA viruses.  Conditions such as AIDS, transmitted by the viruses HIV-1 and HIV-2 which are also RNA viruses, but they are retroviruses, which means that the viral RNA incorporates itself into the host’s DNA (which was one of the reasons that this was so hard to treat in the early days of the disease, although thankfully, it is now very controllable).  

Parasites

In biology, the simple definition of a parasite is an organism that gains benefit at the expense of its host.  It logically follows that parasites want their host to survive for as long as possible.  Viruses are no different although we could all be forgiven for thinking that is not the case when we are in the depths of a pandemic, but in reality, it is rare for a virus to kill off a whole population.  Covid-19 is no different, it is not killing everyone.  In some people, the effects are very mild.  

There are lots of other pathogens (disease causing organisms) out there: bacteria, fungi, to name but two.  We live in a sort of harmony with most of them and we will continue to do so.

© Susan Shirley 2020

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CORONAVIRUS

I decided I’d blog about Coronavirus because I’m fed up with all the misinformation and nonsense that’s been going on about it (no, I’m not minimising it, read on) and was gobsmacked to see the first nine searches that came up were not from medical sites.  I’ve written about it elsewhere this week and only use medical and scientific sites for my information, and then I double check.  Rant over.  Let’s go.

What is Coronavirus

It’s not one virus, it’s a group of viruses that are all related in some way.  They include MERS (Middle East Respiratory Syndrome) and the probably more well-known SARS (Severe Acute Respiratory Syndrome).  This particular virus has the catchy name of COVID-19.

What caused it?

The truth is, at the time of writing, no-one knows the exact source of the outbreak.  What is known, however, is that it is transmitted by what are charmingly known as ‘large respiratory droplets’ and direct or indirect contact with such secretions.  And now for the nice bit: some coronaviruses have been found in faecal material.  I’m not saying that is how COVID-19 is being or has been transmitted, but it comes as no great surprise to me to learn this, since human beings seem to be pretty lax about washing their hands after going to the loo.  I’ll come back to that later.

Basic symptoms

The symptoms, according to Public Health England, are fever, cough and chest tightness, and maybe difficulty breathing.  

Other outbreaks

There was a SARS pandemic back in 2002, with 8098 reported cases and 774 deaths, which means that the mortality rate was about one in ten.  Compare that with the Spanish ‘flu’ pandemic of 1918 where between 20 million and 50 million people died.  More US soldiers died during this pandemic than were killed in battle during World War I.

There was another ‘flu’ pandemic in 1957/8 which killed around 2 million people and a further one in 1968/9 which killed around 1 million people.  

At the moment, the Coronavirus seems to be more like SARS than Spanish ‘flu’ in terms of mortality rates.  As with most of these things, it seems to be worse for the elderly, the very young and those with compromised immune systems, so there is no need to panic.

Precautions

It wasn’t a vaccine that stopped the SARS outbreak back in 2002, it was basic hygiene measures that stopped the virus spreading.  I venture to suggest that it will be the same thing that stops Coronavirus too.

Those basic measures are, as advised by NHS England:

  • Cover your mouth and nose with a tissue, or your sleeve, but not your hands, when you cough or sneeze.  (I know we were all told to cover our mouths with our hands when we were kids and it’s a reflex action now, but actually, all we are doing is getting the virus on our hands which we then use to touch something or someone, thus transmitting the virus.)
  • Put your used tissue straight in the bin.  I accept that this is easier said than done if you are on something like the London Underground.
  • Wash your hands frequently with soap and water (please, especially after going to the loo).  Use hand sanitiser is soap and water are not available.
  • Try to avoid close contact with people who are unwell.

Don’t touch your eyes, nose and mouth if your hands are not clean.

I keep hand sanitiser in my handbag and use it every time I touch money, and, if I can’t wash my hands, before eating. I also use it when I get back to where I was sitting or when I am outside if I use loos in public places – sorry, but I do not trust other people to wash their hands properly.  And if they don’t, they touch handles, etc… You get my drift.

Now for the bad news

Scientists aren’t sure how long Coronaviruses can survive on surfaces.  (Quick biology lesson: viruses are amazing creatures, depending on the type, they can go through dormant phases where they don’t live in or on a host.  Think pharaohs and pyramids.  I am most definitely not saying that Coronaviruses can do this, I don’t know.  What I am saying is, it is better to err on the side of caution.  Back to COVID-19.)

If this virus is anything like SARS or MERS, it will be able to live on surfaces like metal or plastic for nine days.  All the more reason for good hand hygiene.  

The good news

It seems that normal household disinfectants and high temperatures kill the virus.

How to wash your hands properly

I’ve attached a link to the NHS website which has a video and pictures to show you how to wash your hands properly, and I strongly suggest you look at it, but the précised version is:

  1. Spend about 20 seconds washing your hands – about the time it takes to sing ‘Happy Birthday’ twice.  That is “Happy birthday to you, Happy birthday to you, Happy birthday dear Coronavirus, Happy birthday to you,” not just Happy Birthday.
  2. Wet your hands with water.
  3. Apply enough soap to cover your hands.
  4. Rub the palms of your hands together.
  5. Use one hand to rub the back of the other hand.  Clean in between your fingers too.  Do the same thing with the other hand.
  6. Rub your hands together and clean in between your fingers.
  7. Rub the back of your fingers against your palms.  
  8. Rub the thumb of one hand using the other hand and then repeat.
  9. Rub the tips of your fingers of one hand onto the palm of the other hand, then repeat the other way round.
  10. Rinse your hands with water.
  11. Dry with a disposable towel.
  12. Use a disposable towel to turn off the tap.
  13. Job done.

https://www.nhs.uk/live-well/healthy-body/best-way-to-wash-your-hands/

You should wash your hands:

  • after using the toilet or changing a nappy 
  • before and after handling raw foods like meat and vegetables
  • before eating or handling food
  • after blowing your nose, sneezing or coughing
  • before and after treating a cut or wound
  • after touching animals, including pets, their food and after cleaning their cages 

https://www.nhs.uk/conditions/coronavirus-covid-19/

© Susan Shirley 2020