Dealing with resurgent covid19 infections

DR IAN HOSEIN

ALL INFECTIOUS diseases can be classified in two ways – those caused by organisms already carried by humans and those from organisms which are not.

The former, called “endogenous infections,” include bladder and kidney infections caused by the E coli bacterium, which is normally in the human bowel and recto-anal area.

With the latter, termed “exogenous infections,” external organisms (at a distance) must literally reach the human body to gain access and initiate infection. The latter group include TB, flu and covid19.

So this establishes a vital first principle of self-protection and protection of others, and hence outbreak control and termination for exogenous infections like covid19.

This is not radiation – there is no action from a distance. The virus of covid19, SARS CoV 2, must cross the protective spatial barrier and get into your personal space. Why?

Well, it is an exogenous infection but there is a sinister reason underlying the crossing of that spatial barrier. It must cross the barrier to reach its target – your respiratory tract cells. And access to the key cells can occur via contact with the eye, nose, mouth, or by breathing in contaminated air.

I use the word “target” deliberately, since that is precisely what we are talking about here. A target brings up the idea of a focal point of attack – it is the stumps. It’s not your hands that matter to covid19, it’s the target cells in your respiratory tract; but contaminate your hands and rub your eyes, reduce your protective spatial barrier, hug someone, and SARS CoV 2 will say, "Thank you very much for saving my life, even if I must damage your body."

I do like drama, as the lads from my class at Presentation College, Chaguanas, will testify, but this is not drama.

At a time of so much uncertainty about what is true, let me give you what is true and undisputable.

Covid19 is a virus and as such it is what we term an obligate intracellular pathogen, meaning it will die unless inside living cells.

An infected human has two possible outcomes: recovery and the virus dies, or death and the virus also dies. There is no known chronic infection syndrome with long-term infectivity as with, say, hepatitis B.

In this pandemic it has no other source for transmission than another human being.

So, pulling all this together: SARS CoV 2 must invade a new host to sustain its very existence.

It needs you to drop your defences to get access to your target cells to sustain its life.

Of course, we are still learning about this new foe, but we know enough about our enemy to counterattack and terminate outbreaks.

Safe distance – do not reduce your protective spatial barrier. It is not being antisocial –you are attacking SARS CoV 2 with your barrier.

Safe hands – hands are designed to touch and handle items, so can be readily contaminated; hence practise frequent hand hygiene.

Safe face – protect your face from contaminated hands and wear face coverings when in gatherings. There is a significant dilution effect against the virus if you are outdoors, so it is safer to meet in the open air.

The analyses given at the beginning of this article justify the controls given above, and these can be highly effective in terminating community spread.

Dr Ian Hosein is the associate medical director and director of infection prevention and control, Medway Maritime Hospital, UK, and visiting professor at UWI, St Augustine